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  • richardmitnick 6:07 am on October 25, 2017 Permalink | Reply
    Tags: , Climate Change, , Herbivores help protect marine ecosystems from climate change,   

    From ICL: “Herbivores help protect marine ecosystems from climate change” 

    Imperial College London
    Imperial College London

    25 October 2017
    Hayley Dunning

    1
    A limpet on seaweed. Image: Rebecca Kordas

    Plant-eating critters are key to helping ecosystems survive global warming, offering some hope for a defence strategy against climate change.

    An international research team created miniature marine ecosystems and tested how they fared in warmer conditions. They found that in the hottest conditions, ecosystems that included limpets – voracious snail-like marine herbivores – fared the best.

    The study, published in Science Advances, monitored mini ecosystems on rocky shores made up of different collections of organisms. The ecosystems were grown on special hard plastic plates that could be individually warmed. This allowed the researchers to test how the different ecosystems responded to temperature rises while in their natural habitat.

    Ecosystems are in a delicate balance: removing organisms that do key jobs can cause the whole system to deteriorate. If this ecosystem is then put under stress, it is less able to cope and can collapse.

    In these experiments, it was the key job performed by the main herbivore (limpets) that helped the ecosystems stay resilient in the face of warming. Limpets are voracious consumers of algae, and their action prevents algae from building up and using all the available space – a valuable resource on rocky shores.

    Variety needed

    Lead author of the study Dr Rebecca Kordas, who completed this research for her PhD at the University of British Columbia and is now a research fellow at Imperial College London, said: “The herbivores created space for other plants and animals to move in and we saw much more diversity and variety in these ecosystems.

    “We want variety because we found it helps protect the ecosystem when you add a stressor like heat.”

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    The experimental plates underwater. Image: Rebecca Kordas

    The research team studied life in the intertidal zone, the area of the shore between the low tide and high tide, on the coast of British Columbia. This area is home to a community of starfish, anemones, mussels, barnacles and seaweed. As the tide moves in and out, the plants and animals must cope with huge variation in temperature every day, sometimes as much as 20 to 25 degrees Celsius.

    Despite dealing daily with these extremes, the ecosystems can be severely damaged by further warming. Dr Kordas said: “When heat waves come through British Columbia and the Pacific Northwest, we see mass mortality of numerous intertidal species.

    “These creatures are already living at their physical limits, so a two-degree change – a conservative prediction of the warming expected over the next 80 years or so – can make a big difference.”

    Making ecosystems more resilient

    The researchers found that in the summer, when temperatures were at their warmest, communities could fare well even if they were heated, but only if limpets were present. Dr Kordas added: “When limpets were part of the community, the effects of warming were less harsh.”

    3
    Plates along the shore in Ruckle Park, British Columbia. Image: Rebecca Kordas

    Senior study author Professor Christopher Harley from the University of British Columbia says that, in general – consumers like limpets, sea otters or starfish are very important to maintaining biodiversity, especially in aquatic ecosystems. Losing these species can destabilize ecosystems, but protecting them can make ecosystems more resilient.

    “We should be thinking of ways to reduce our negative effects on the natural environment and these results show that if we do basic conservation and management, it can make a big difference in terms of how ecosystems will weather climate change,” Professor Harley said.

    See the full article here .

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    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

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  • richardmitnick 1:02 pm on September 23, 2017 Permalink | Reply
    Tags: , , , Climate Change, , , New science,   

    From WCG: “Supercharging Environmental and Climate Change Research” 

    New WCG Logo

    WCGLarge

    World Community Grid (WCG)

    10 Jul 2017 {Just popped up in social media.]

    Summary
    IBM invites scientists to apply for grants of supercomputing power through World Community Grid, meteorological data from The Weather Company, and IBM Cloud storage to support their environmental and climate change research projects.

    World Community Grid supports research that tackles our planet’s most pressing challenges, including environmental issues. That’s why we’re pleased to announce a new partnership with The Weather Company (an IBM business) and IBM Cloud to provide free technology and data for environmental and climate change projects.

    Environmental scientists have long been warning the public about the effects of climate change, and many researchers attribute events such as this summer’s record temperatures in western Europe and the worst drought since the 1940s in parts of Africa to climate change caused by humankind’s activities. The future consequences of climate change could include rising sea levels, potential crop loss, and harsh economic consequences throughout the world. And as funding for scientific research shrinks in many countries, the gap between what scientists must discover–how to mitigate or adapt to climate change–and their resources for such discovery is growing ever wider.

    Thanks to the contributions of volunteers all over the globe, World Community Grid is ready to address that gap. Since 2004, our research partners have completed the equivalent of thousands of years of work in just a few years, including enabling advances in environmental science.

    For example, scientists at Harvard University used World Community Grid to run the Clean Energy Project [see below], the world’s largest quantum chemistry experiment with the goal of identifying new materials for solar energy. In just a few years, they analyzed millions of chemical compounds to predict their efficiency at converting sunlight into electricity. Their discovery of thousands of promising compounds could advance the development of cheap, flexible solar cell materials that we hope will be used worldwide to reduce carbon emissions and contribute to the fight against climate change.

    Other environmental research projects conducted with help from World Community Grid have included new water filtration technology [see below], watershed preservation and crop sustainability.

    That’s why we’re pleased to announce that IBM is inviting scientists around the world to apply for grants of supercomputing power from World Community Grid, meteorological data from The Weather Company, and IBM Cloud storage to support their climate change or environmental research projects. Up to five of the most promising environmental and climate-related research projects will be supported. This support, technology, and data can support many potential areas of inquiry, such as impacts on fresh water resources, predicting migration patterns, and developing models to improve crop resilience.

    Proposals for projects will be evaluated for scientific merit, potential to contribute to the global community’s understanding of specific climate and environmental challenges and development of effective strategies to mitigate them, and the capacity of the research team to manage a sustained research project. And like all other World Community Grid projects, researchers who receive these resources must agree to abide by our open data policy by publicly releasing the data from their collaboration with us.

    Scientists from around the world can apply at http://climate.worldcommunitygrid.org, with a first round deadline of September 15.

    There’s still time to mitigate or adapt to the effects of climate change, and scientific research will continue to play a crucial role in how our planet addresses this crisis. We hope you will join us by giving your computers the ability to work around the clock for science.

    Scientists Apply Here.

    See the full article here.

    Ways to access the blog:
    https://sciencesprings.wordpress.com
    http://facebook.com/sciencesprings

    Please help promote STEM in your local schools.
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    World Community Grid (WCG) brings people together from across the globe to create the largest non-profit computing grid benefiting humanity. It does this by pooling surplus computer processing power. We believe that innovation combined with visionary scientific research and large-scale volunteerism can help make the planet smarter. Our success depends on like-minded individuals – like you.”
    WCG projects run on BOINC software from UC Berkeley.
    BOINCLarge

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing.

    BOINC WallPaper

    CAN ONE PERSON MAKE A DIFFERENCE? YOU BET!!

    My BOINC
    MyBOINC
    “Download and install secure, free software that captures your computer’s spare power when it is on, but idle. You will then be a World Community Grid volunteer. It’s that simple!” You can download the software at either WCG or BOINC.

    Please visit the project pages-

    FightAIDS@home Phase II

    FAAH Phase II
    OpenZika

    Rutgers Open Zika

    Help Stop TB
    WCG Help Stop TB
    Outsmart Ebola together

    Outsmart Ebola Together

    Mapping Cancer Markers
    mappingcancermarkers2

    Uncovering Genome Mysteries
    Uncovering Genome Mysteries

    Say No to Schistosoma

    GO Fight Against Malaria

    Drug Search for Leishmaniasis

    Computing for Clean Water

    The Clean Energy Project

    Discovering Dengue Drugs – Together

    Help Cure Muscular Dystrophy

    Help Fight Childhood Cancer

    Help Conquer Cancer

    Human Proteome Folding

    FightAIDS@Home

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    faah-1-new

    World Community Grid is a social initiative of IBM Corporation
    IBM Corporation
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    IBM – Smarter Planet
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  • richardmitnick 8:08 am on September 13, 2017 Permalink | Reply
    Tags: , Climate Change, , Opinion: How Antarctic ice melt can be a tipping point for the planet’s climate,   

    From UNSW- Opinion: How Antarctic ice melt can be a tipping point for the planet’s climate” 

    U NSW bloc

    University of New South Wales

    13 Sep 2017
    Chris Turney
    Jonathan Palmer
    Peter Kershaw
    Steven Phipps
    Zoë Thomas

    New research has prompted warnings that melting Antarctic ice can trigger effects on the other side of the globe.

    1
    Photo: Shutterstock

    OPINION: Melting of Antarctica’s ice can trigger rapid warming on the other side of the planet, according to our new research [Nature Communications] which details how just such an abrupt climate event happened 30,000 years ago, in which the North Atlantic region warmed dramatically.

    This idea of “tipping points” in Earth’s system has had something of a bad rap ever since the 2004 blockbuster The Day After Tomorrow purportedly showed how melting polar ice can trigger all manner of global changes.

    But while the movie certainly exaggerated the speed and severity of abrupt climate change, we do know that many natural systems are vulnerable to being pushed into different modes of operation. The melting of Greenland’s ice sheet, the retreat of Arctic summer sea ice, and the collapse of the global ocean circulation are all examples of potential vulnerability in a future, warmer world.

    Of course, it is notoriously hard to predict when and where elements of Earth’s system will abruptly tip into a different state. A key limitation is that historical climate records are often too short to test the skill of our computer models used to predict future environmental change, hampering our ability to plan for potential abrupt changes.

    Fortunately, however, nature preserves a wealth of evidence in the landscape that allows us to understand how longer time-scale shifts can happen [Science Direct].

    Core values

    One of the most important sources of information on past climate tipping points are the kilometre-long cores of ice drilled from the Greenland and Antarctic ice sheets, which preserve exquisitely detailed information stretching back up to 800,000 years [The Conversation].

    The Greenland ice cores record massive, millennial-scale swings in temperature [Geophysical Research Letters] that have occurred across the North Atlantic region over the past 90,000 years. The scale of these swings is staggering: in some cases temperatures rose by 16℃ in just a few decades or even years.

    Twenty-five of these major so-called Dansgaard–Oeschger (D-O) [NOAA] warming events have been identified. These abrupt swings in temperature happened too quickly to have been caused by Earth’s slowly changing orbit around the Sun. Fascinatingly, when ice cores from Antarctica are compared with those from Greenland, we see a “seesaw” relationship: when it warms in the north, the south cools, and vice versa.

    Attempts to explain the cause of this bipolar seesaw have traditionally focused on the North Atlantic region, and include melting ice sheets, changes in ocean circulation or wind patterns.

    But as our new research shows, these might not be the only cause of D-O events.

    Our new paper, published today in Nature Communications [link is above], suggests that another mechanism, with its origins in Antarctica, has also contributed to these rapid seesaws in global temperature.

    Tree of knowledge

    We know that there have been major collapses of the Antarctic ice sheet in the past [Science], raising the possibility that these may have tipped one or more parts of the Earth system into a different state. To investigate this idea, we analysed an ancient New Zealand kauri tree that was extracted from a peat swamp near Dargaville, Northland, and which lived between 29,000 and 31,000 years ago.”>major collapses of the Antarctic ice sheet in the past, raising the possibility that these may have tipped one or more parts of the Earth system into a different state. To investigate this idea, we analysed an ancient New Zealand kauri tree that was extracted from a peat swamp near Dargaville, Northland, and which lived between 29,000 and 31,000 years ago.

    Through accurate dating, we know that this tree lived through a short D-O event, during which (as explained above) temperatures in the Northern Hemisphere would have risen. Importantly, the unique pattern of atmospheric radioactive carbon (or carbon-14) found in the tree rings allowed us to identify similar changes preserved in climate records from ocean and ice cores (the latter using beryllium-10, an isotope formed by similar processes to carbon-14). This tree thus allows us to compare directly what the climate was doing during a D-O event beyond the polar regions, providing a global picture.

    The extraordinary thing we discovered is that the warm D-O event coincided with a 400-year period of surface cooling in the south and a major retreat of Antarctic ice.

    When we searched through other climate records for more information about what was happening at the time, we found no evidence of a change in ocean circulation. Instead we found a collapse in the rain-bearing Pacific trade winds over tropical northeast Australia that was coincident with the 400-year southern cooling.

    To explore how melting Antarctic ice might cause such dramatic change in the global climate, we used a climate model to simulate the release of large volumes of freshwater into the Southern Ocean. The model simulations all showed the same response, in agreement with our climate reconstructions: regardless of the amount of freshwater released into the Southern Ocean, the surface waters of the tropical Pacific nevertheless warmed, causing changes to wind patterns that in turn triggered the North Atlantic to warm too.

    Future work is now focusing on what caused the Antarctic ice sheets to retreat so dramatically. Regardless of how it happened, it looks like melting ice in the south can drive abrupt global change, something of which we should be aware in a future warmer world.

    Chris Turney, Professor of Earth Sciences and Climate Change, UNSW; Jonathan Palmer, Research Fellow, School of Biological, Earth and Environmental Sciences, UNSW; Peter Kershaw, Emeritus Professor, Earth, Atmosphere and Environment, Monash University; Steven Phipps, Palaeo Ice Sheet Modeller, University of Tasmania, and Zoë Thomas, Research Associate, UNSW.

    See the full article here .

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    U NSW Campus

    Welcome to UNSW Australia (The University of New South Wales), one of Australia’s leading research and teaching universities. At UNSW, we take pride in the broad range and high quality of our teaching programs. Our teaching gains strength and currency from our research activities, strong industry links and our international nature; UNSW has a strong regional and global engagement.

    In developing new ideas and promoting lasting knowledge we are creating an academic environment where outstanding students and scholars from around the world can be inspired to excel in their programs of study and research. Partnerships with both local and global communities allow UNSW to share knowledge, debate and research outcomes. UNSW’s public events include concert performances, open days and public forums on issues such as the environment, healthcare and global politics. We encourage you to explore the UNSW website so you can find out more about what we do.

     
    • Agustin 7:49 am on September 14, 2017 Permalink | Reply

      Actually when someone doesn’t understand after that its up to other people that they will help, so
      here it occurs.

      Like

  • richardmitnick 7:01 am on September 13, 2017 Permalink | Reply
    Tags: , Climate Change, ,   

    From Paulson: “From sea to rising sea: Climate change in America” 

    Harvard School of Engineering and Applied Sciences
    Harvard John A. Paulson School of Engineering and Applied Sciences

    1
    Climate change and health in America. No image credit

    Climate change will affect every American in the coming decades — the question is, to what degree?

    9.13.17
    Leah Burrows

    So, the climate is getting warmer. Who cares?

    Climate change has a PR problem in America.

    For decades, we called it ‘global warming,’ an innocuous-sounding phrase invoking a gentle increase in worldwide temperatures, like turning up the thermostat in a house.

    “People asked, so the climate is getting warmer. Who cares?” said Michael B. McElroy, the Gilbert Butler Professor of Environmental Studies at Harvard University. “And scientists are partly to blame for that because of how we’ve described climate change.”

    It’s been difficult to get Americans worried about a 1-degree increase in temperature over a 100-year period, especially when most of the images associated with global warming — crumbling ice sheets or a lonely polar bear padding across a melted landscape — feel so distant.

    But climate change is here. Mitigating the effects of global warming — better described as irreversible changes to the climate structure — is about more than saving the planet in the longer term; it’s about saving human lives in the near term.

    From severe storms and catastrophic flooding to record-breaking droughts and deadly wildfires, Americans are living with the consequences of a changing climate every day. Still, the majority of Americans did not believe climate change would harm them personally, according to a Yale University study [no citation]. That connection — between climate change and human health — has been, in large part, missing from public conversations and political debate in America today.

    2
    Howe, Peter D., Matto Mildenberger, Jennifer R. Marlon, and Anthony Leiserowitz (2015). “Geographic variation in opinions on climate change at state and local scales in the USA.” Nature Climate Change, doi:10.1038/nclimate2583

    Researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) are exploring that connection between human health and a changing climate. Among their findings: In Pennsylvania, days with dangerously high surface ozone levels could increase by 100 percent in the coming decades, increasing the risk of asthma and other respiratory diseases in children. Wildfires in Washington could choke densely populated areas for days with thick, harmful smoke. Severe storms in Texas, Oklahoma, Nebraska, Iowa, the Dakotas and adjoining states could deplete protective ozone in the stratosphere, exposing humans, livestock and crops to harmful ultraviolet radiation.

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    No image caption or credit.

    The Eastern U.S.: The heat is rising

    If the world were to cut all of its carbon emissions tomorrow, temperatures have already risen enough to cause more severe and prolonged heat waves. Extreme heat has serious impact on human health. Depending on humidity levels, prolonged exposure to 100-plus degree days can lead to heat stroke and dehydration, as well as cardiovascular, respiratory, and cerebrovascular diseases.

    In the past decade, extreme heat waves in the U.S. have killed hundreds of people, mostly elderly and poor in urban areas, and cost tens of billions in damage. Northern cities, such as Chicago, New York, Philadelphia and Boston, which are less prepared to deal with excessive temperatures, will likely face the brunt of the public health burden of heat waves in coming years.

    With little ability to stop future heat waves, the best option to mitigate damage is preparation. Improving our ability to accurately predict heat waves can save lives.

    Most current models cannot forecast beyond about 10 days and seasonal models have limited ability to predict extreme events. In 2012, for example, the National Weather Service’s Climate Prediction Center forecasted normal summer temperatures in the Northeast and Midwest U.S. Instead, the regions experienced three separate, record-breaking heat events in June and July that resulted in more than 100 deaths.

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    Peter Huybers, professor of earth and planetary sciences and of environmental science and engineering (Photo courtesy of Eliza Grinnell)

    Peter Huybers, Professor of Earth and Planetary Sciences in the Department of Earth and Planetary Sciences and of Environmental Science and Engineering at SEAS, is working to understand and predict these deadly temperature spikes. Huybers and his lab identified sea surface temperature patterns that can predict increased odds of extreme heat waves in the eastern U.S. up to 50 days in advance. Those patterns — like a fingerprint on the surface of the Pacific Ocean — consistently precede heat waves in the eastern U.S.

    The Huybers team found that lack of precipitation, which is known to contribute to heat waves, is also associated with this finger print — known as the Pacific Extreme Pattern. While it does not guarantee that a heat wave will strike, seeing this pattern significantly increases the odds of one happening.

    “Our technique was able to predict previous heat waves, including the deadly heat waves of 2012, and was skillful when applied to earlier events between 1950 and 1980,” said Huybers. “However, the technique doesn’t predict the Dust Bowl years of the 1930s, reminding us that other environmental factors must also be important.”

    Huybers and his colleagues are continuing to research this connection, pushing the horizon on predicting summer heat waves in the eastern U.S.

    With more time to prepare, utility companies could ensure they have enough power options to deal with a spike in demand; farmers could alter irrigation tactics to prevent crop loss; city planners could set up cooling spaces for the elderly or those without air conditioners and step up programs to track homeless people and homebound, chronically ill older Americans.

    As the air warms due to global climate change, Northeastern urban and suburban areas could also see an increase in ground level ozone — the nasty chemical compound that makes up the majority of smog, especially in summer.

    Ground level ozone is created by chemical reactions involving oxides of nitrogen (NOx), volatile organic compounds (VOCs) and sunlight. Factories, power plants and cars produce most of the NOx in the U.S.

    Ozone is well known to cause serious respiratory illness and is especially dangerous for children, seniors, and people suffering from asthma.

    “Even short-term exposure to ozone over a few hours or days has been linked to serious health effects,” said Loretta J. Mickley, Senior Research Fellow in Chemistry-Climate Interactions in the Atmospheric Chemistry Modeling Group. “High levels of ozone can exacerbate chronic lung disease and increase death rates.”

    _______________________________________________________________________
    The power of regulation

    It’s easy to feel helpless and overwhelmed in the face of global climate change but legislative action can make a difference when it comes to the environment. Elsie Sunderland, the Thomas D. Cabot Associate Professor of Environmental Science and Engineering, found that regulations requiring the reduction of mercury emissions had a larger impact on the environment than researchers previously thought. Between 1990 and 2010, global mercury emissions from manmade sources declined 30 percent. The reduction in atmospheric mercury was most pronounced over North America, where mercury had been gradually phased out of many commercial products and controls were put in place on coal-fired power plants that removed naturally occurring mercury from the coal being burned.

    _______________________________________________________________________

    Researchers have long known that temperature and ozone are linked — the hotter the temperature, the higher the ozone levels. However, researchers have also established that if the temperatures rise above the mid-90s Fahrenheit, this relationship can break down. So, the question is: how will rising global temperatures impact the severity and frequency of days with dangerously high levels of ground ozone, known as ozone episodes?

    Mickley and her team are unraveling the complex relationship between ozone and rising temperatures in the U.S.

    In 2016, graduate student Lu Shen and Mickley found that if local and global emissions continue unchecked and temperatures rise as projected, the U.S. could see a 70- to 100-percent increase in dangerous ozone episodes, depending on the region.

    The Northeast, California and parts of the Southwest, would be most affected, experiencing up to nine additional days per year of unhealthy ozone levels in the next 50 years. The rest of the country could experience up to three additional days of unhealthy ozone.

    What does that mean for health in the U.S.? Hospital admissions and emergency department visits would increase, cases of chronic respiratory conditions, such as asthma and chronic bronchitis, would increase, and more people could die from respiratory illness.

    “We need ambitious emissions controls to offset the potential of more than a week of additional days with unhealthy ozone levels,” said Mickley.

    The good news is, we’ve already seen the powerful effect regulation has on ozone levels in the U.S. Between 1990 and 2016, ozone levels decreased significantly, especially on the east coast, thanks to the Clean Air Act and its amendments, which targeted ozone precursors.

    The bad news is that high temperatures can upend that trend.

    5
    The graph shows 15 years of surface ozone measurements in Madison County, Illinois. Since 1990, ozone decreased over time due to the powerful Clean Air Act and its amendments, which reduced emissions of ozone precursors. But very hot temperatures — as seen in 2012 — buck that trend. A similar pattern was seen at measuring sites across the country. A full, interactive map is available here.

    Mickley and her team are also developing tools to predict when and where Americans are most at risk for increased levels of ozone in the short-term.

    The researchers found that high levels of summertime ozone in the Eastern U.S. are correlated with large-scale meteorological patterns in the spring, including sea surface temperatures. The team used this relationship to predict average summertime ozone levels one season in advance.

    “A prediction tool could act as an early warning system to communities most at risk for high-ozone days,” said Mickley. “Local communities could mobilize resources and plan protocols to help its most at-risk citizens, including children and seniors, during episodes in the upcoming ozone season. Such protocols could include advisories for people to stay indoors.”

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    No image caption or credit.

    Brewing storms in the Midwest

    As temperatures increase and more water vapor evaporates into the atmosphere, storms will become more frequent and more intense — especially in the Midwest.

    Flooding and damage associated with these storms is a threat to the lives and livelihood of the 60 million people living in the Midwestern states, especially farmers who rely on predictable rainfall patterns. But the intensity of these storms, combined with factors unique to the Great Plains region, may also damage the protective ozone layer that shields life on Earth from harmful ultraviolet radiation.

    James G. Anderson, the Philip S. Weld Professor of Atmospheric Chemistry at SEAS and the Department of Earth and Planetary Sciences, is studying this phenomena. In 2012, his team discovered that during intense summer storms over the Midwest, water vapor from these storms is injected deep into the stratosphere. By studying ozone loss over the Arctic in winter, Anderson and his collaborators established that combinations of both temperature and water vapor convert stable forms of chlorine and bromine into free radicals capable of transforming ozone molecules into oxygen, implicating storm-injected water vapor in the loss of ozone over the U.S. in summer.

    By using advanced radar techniques, Anderson and his team, including researchers at Texas A&M and the University of Oklahoma, recently found that thousands of storms each summer penetrate the stratosphere to provide fuel for these reactions — far more than previously thought.

    “Rather than large, continental scale ozone loss that occurs over the polar regions in winter, these radar observations and our new high accuracy, high spatial resolution temperature measurements found that the structure of ozone loss in the central U.S. is highly localized over numerous regions,” said Anderson.

    These reactions, depending on the temperature of the stratosphere, could trigger a 12- to 17-percent decrease in ozone in the lower stratosphere one week after a storm. This corresponds to a 2- to 3-percent decrease in stratospheric ozone in the region of enhanced water vapor. Even a 1-percent decrease in stratospheric ozone can lead to a 3-percent increase in skin cancer in humans – there are three and a half million new cases of skin cancer diagnosed each year in the U.S. alone. Since ultraviolet radiation also impairs the molecular chemistry of photosynthesis, such a change could also have a major effect on agriculture in the Midwest.

    “This isn’t about just human health, this is about crop yields, livestock, and the ability to function for extended periods outside in the summer,” said Anderson.

    Anderson and his lab are developing new platforms to observe this phenomena in action. Central to that effort is a research platform called the StratoCruiser, a super-pressure balloon designed to collect data at an average of 75,000 feet — well into the stratosphere.

    Powered by an array of solar cells, the StratoCruiser will fly above the central U.S. for four to six weeks, collecting data on how water vapor injected into the stratosphere alters the properties of particles and initiates the series of chemical reactions that destroy ozone.

    Anderson and his team are developing sensing instruments sturdy enough to withstand winds and rain from intense convective storms yet lightweight enough to allow the instrument package, suspended on a Kevlar filament below the balloon, to sample air between 40,000ft and 75,000ft.

    The instruments have to work at temperatures ranging from minus 120 degrees to plus 90 degrees Fahrenheit, withstand the low pressure of the upper atmosphere, power themselves and operate autonomously for the six-week mission.

    SEAS undergraduates in Anderson’s Engineering Problem Solving and Design Project (ES 96) are playing an important role in solving these design challenges. The student team who designed a spectrometer that measures hydrochloric acid (HCl) in the atmosphere was awarded $200,000 from NASA’s Undergraduate Student Instrument Project grant. The new instrument will be launched by NASA fall 2017 from Ft. Sumner, New Mexico.

    Another ES 96 project for undergraduates involves designing and building a new class of instruments to measure free radicals and other reactive species from solar powered stratospheric aircraft. These instruments, which will collect data over the U.S. continuously for three months, will provide the ability to forecast the amount of UV radiation projected for specific regions of the Great Plains states in summer. The solar powered stratospheric aircraft can also circumnavigate the globe to obtain observations related to the response of the climate structure to increasing levels of carbon dioxide and methane.

    One of the biggest questions Anderson and others want to answer is whether or not the process of ozone depletion is reversible.

    Anderson knows how well-communicated science can spur action on climate change. It was his research in the late 1980s that finally proved the link between chlorofluorocarbons (CFCs) from aerosol cans, air conditioners and refrigerators and the Antarctic ozone hole. The discovery was the key step towards public acceptance of the connection, which ultimately led to the phase-out of CFCs under 197-country Montreal Protocol signed in 1987.

    “We saw the power of regulation and legislation when global powers got together and decided to ban CFCs,” said Anderson. “After that, we thought we’d solved the problem of ozone depletion. Now, it could be made much worse than we thought by climate change. If we continue on this course, decreases in ozone and associated increases in UV dosage could be irreversible.”

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    No image caption or credit.

    The West is burning

    In 2016 alone, more than 67,000 wildfires burned over 5.5 million acres in the U.S., an area equivalent to the size of New Jersey. If global warming continues on pace, the models predict that by 2050 the wildfire season in the western U.S. will be about three weeks longer, twice as smoky, and will burn more area. In the coming decades, the area burned in August could increase by 65 percent in the Pacific Northwest; could nearly double in the Eastern Rocky Mountains/Great Plains; and quadruple in the Rocky Mountains Forest region.

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    Liu, JC, LJ Mickley, MP Sulprizio, X Yue, K Ebisu, GB Anderson, R Khan, ML Bell. 2016. Particulate Air Pollution from Wildfires in the Western US under climate change. Climatic Change. 138 (3): 655-666. View the interactive map here.

    But wildfires threaten more than land and homes. The smoke they produce contains particles that can contaminate the air hundreds of miles away. As wildfires increase in frequency and intensity, more and more communities are at risk of prolonged exposure to harmful levels of smoke, including heavily populated areas such as California’s San Francisco, Alameda, and Contra Costa counties, and King County in Washington.

    Mickley and the Atmospheric Chemistry Modeling Group are developing tools to predict how wildfires will impact air quality. The work is part of a collaboration with Yale University.

    Between 2004 and 2009, about 57 million people in the western U.S. experienced a smoke wave, a term Mickley and her colleagues coined to describe two or more consecutive days of unhealthy levels of smoke from fires. Between 2046 and 2051, the team estimated more than 82 million people are likely to be affected by smoke waves, mostly in Northern California, Western Oregon and the Great Plains, where fire fuel is plentiful.

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    Loretta J. Mickley, Senior Research Fellow in Chemistry-Climate Interactions (Photo courtesy of Eliza Grinnell/Harvard SEAS)

    All across the western U.S., climate change will likely cause smoke waves to be longer, more intense, and more frequent. About 13 million more children and seniors — who are at higher risk for respiratory illness — will be affected by smoke waves compared with the present day.

    Mickley and her team have developed a model to predict, at the county level, areas most at risk for smoke waves. The model would allow local governments or the U.S. Forest Service to prioritize these areas in fire mitigation efforts such as clearing out dry underbrush or performing controlled burns.

    “No matter what ignites a wildfire, whether by lightning or human carelessness, the spread of a fire is determined by the availability of dry, easily combustible fuel,” said Mickley. “We’re currently seeing and we will continue to see in future decades, warmer temperatures increase the supply of such fuel. The massive fires of 2016 are likely an indication of what’s to come.”

    _______________________________________________________________________

    How we know what we know

    For nearly 20 years, the GEOS-Chem global transport model has provided hundreds of research groups around the world insight into the chemical composition of the atmosphere and how it is being impacted by human activity. Developed by Daniel Jacobs, the Vasco McCoy Family Professor of Atmospheric Chemistry and Environmental Engineering at SEAS and the Department of Earth and Planetary Sciences, and housed at Harvard University, the open source model is an international standard for modeling pollution. Since its inception, the model has been used to understand the global biogeochemical cycling of mercury; the intercontinental transport of air pollution, which is critical to EPA’s setting of air quality standards; and has added considerably to the knowledge of worldwide emissions of pollutants and climate gases.
    _______________________________________________________________________

    Pollution knows no borders

    It’s not just the continental U.S. that is facing health consequences from global climate change. Alaska, Hawaii and many American territories are on the front lines of climate change.

    In 2016, a DC-8 loaded with scientific instruments took off from Palmdale, California, ascending through a sky thick with wildfire smoke and smog from nearby Los Angeles.

    It was a fitting start to the first leg of the Atmospheric Tomography Mission (ATom), led by Steven C. Wofsy, the Abbott Lawrence Rotch Professor of Atmospheric and Environmental Science at SEAS and the Department of Earth and Planetary Sciences. Since 2016, the ATom mission has made two trips around the world — pole to pole — taking atmospheric measurements to understand how pollution and greenhouse gasses move through the atmosphere.

    The ATom mission, in partnership with NASA, will fly a total of four trips around the world. The data it collects will help improve the accuracy of the environmental models that inform climate policies.

    That first leg gave the research team a sobering view of the scope of climate change in America and American territories. Several hours after leaving the searing heat and wildfires of California, the team flew over Alaska, where large dark pools of water disrupted what should have been a continuous sheet of white, polar ice.

    “The contrast between the environments could not have been more dramatic yet, both places were experiencing huge impacts from the warming climate,” said Wofsy.

    And even though no major fires were burning in northern Alaska when the ATom team conducted their first mission, the researchers recorded high levels of pollution from wildfires burning hundreds of miles away, in the forests of Siberia.

    “Pollution can be transported anywhere,” said Roisin Commane, research associate in environmental science and engineering at SEAS and member of the ATom team. “We saw pollution thousands of miles from shore, in what should have been some of the cleanest air in the world. We saw pollution from Asia transported over the Pacific Ocean and pollution from the U.S. over the Atlantic. Pollution has no borders.”


    Wofsy and Paul Newman of NASA’s Goddard Space Flight Center sent back a video postcard of the first two legs of their Atmospheric Tomography, or ATom mission. The science team first traveled from Palmdale, California, to Anchorage, Alaksa, by way of the North Pole, and on their second leg flew south to Kona, Hawaii. (Credit: NASA’s Goddard Space flight Center/Michael Randazzo)

    Engineering hope

    These consequences of global warming in the U.S. also know no borders— it affects young and old Americans, East Coast urbanites and Midwestern farmers.

    In addition to leading efforts to understand the systems that contribute to a warming planet, researchers at SEAS are also developing new tools and technologies to help reverse, or at least slow, the process. That includes projects aimed at generating clean power and storing it in long-lasting batteries.

    Eric Mazur, the Balkanski Professor of Physics and Applied Physics, has researched the properties of nanoscale structures in silicon, which have promising applications to improve the capacity of solar cells. Jennifer Lewis, the Hansjörg Wyss Professor of Biologically Inspired Engineering, has helped develop materials for carbon capture and sequestration.

    Professors Michael Aziz, the Gene and Tracy Sykes Professor of Materials and Energy Technologies; and Roy Gordon, the Thomas Dudley Cabot Professor of Chemistry and Professor of Materials Science, are developing non-toxic, long-lasting and cost effective flow batteries to store power from intermittent energy sources, like wind and solar.

    SEAS undergraduates are getting involved in the effort as well on Harvard’s campus.

    In an ES96 class, SEAS students worked with the university’s Office for Sustainability to evaluate approaches to climate change resilience and develop strategies to enhance the integrity of the electrical grid, cool buildings during extreme heat, and minimize damage from flooding.

    “While we may have dysfunction in Washington, parts of the U.S. are doing serious things about climate change,” said McElroy. “California and New England are shining examples. Mayors of major U.S. cities have been leaders in tackling these issues. So, on the optimistic side, there are signs that people can get together and get things done.”

    It’s important not to lose that optimism, said Wofsy.

    He and the ATom team saw something else on that first flight from California: solar and wind farms generating carbon-free electricity.

    “This sight was much more hopeful,” Wofsy said. “If we apply our minds and resources to the problem, we can make significant progress in slowing the increase in atmospheric CO2. But it’s a generational challenge.”

    See the full article here .

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    Through research and scholarship, the Harvard School of Engineering and Applied Sciences (SEAS) will create collaborative bridges across Harvard and educate the next generation of global leaders. By harnessing the power of engineering and applied sciences we will address the greatest challenges facing our society.

    Specifically, that means that SEAS will provide to all Harvard College students an introduction to and familiarity with engineering and technology as this is essential knowledge in the 21st century.

    Moreover, our concentrators will be immersed in the liberal arts environment and be able to understand the societal context for their problem solving, capable of working seamlessly withothers, including those in the arts, the sciences, and the professional schools. They will focus on the fundamental engineering and applied science disciplines for the 21st century; as we will not teach legacy 20th century engineering disciplines.

    Instead, our curriculum will be rigorous but inviting to students, and be infused with active learning, interdisciplinary research, entrepreneurship and engineering design experiences. For our concentrators and graduate students, we will educate “T-shaped” individuals – with depth in one discipline but capable of working seamlessly with others, including arts, humanities, natural science and social science.

    To address current and future societal challenges, knowledge from fundamental science, art, and the humanities must all be linked through the application of engineering principles with the professions of law, medicine, public policy, design and business practice.

    In other words, solving important issues requires a multidisciplinary approach.

    With the combined strengths of SEAS, the Faculty of Arts and Sciences, and the professional schools, Harvard is ideally positioned to both broadly educate the next generation of leaders who understand the complexities of technology and society and to use its intellectual resources and innovative thinking to meet the challenges of the 21st century.

    Ultimately, we will provide to our graduates a rigorous quantitative liberal arts education that is an excellent launching point for any career and profession.

     
  • richardmitnick 11:33 am on July 24, 2017 Permalink | Reply
    Tags: , Climate Change, , ,   

    From CSIRO: “Extreme El Niño events to stay despite stabilisation” 

    CSIRO bloc

    Commonwealth Scientific and Industrial Research Organisation

    25 Jul 2017
    Chris Gerbing
    Communication Manager, Oceans And Atmosphere
    Phone +61 3 9545 2312
    Chris.Gerbing@csiro.au

    The frequency of extreme El Niño events is projected to increase for a further century after global mean temperature is stabilised at 1.5°C above pre-industrial levels.

    1
    Yale.

    Research published today in Nature Climate Change by an international team shows that if warming was halted to the aspirational 1.5°C target from the Paris Agreement, the frequency of extreme El Niño events could continue to increase, due to a continuation of faster warming in the eastern equatorial Pacific.

    CSIRO researcher and lead author Dr Guojian Wang said the growing risk of extreme El Niño events did not stabilise in a stabilised climate.

    “Currently the risk of extreme El Niño events is around five events per 100 years,” Dr Wang said.

    “This doubles to approximately 10 events per 100 years by 2050, when our modelled emissions scenario (RCP 2.6) reaches a peak of 1.5°C warming.

    “After this, as faster warming in the eastern equatorial Pacific persists, the risk of extreme El Niño continues upwards to about 14 events per 100 years by 2150.

    “This result is unexpected and shows that future generations will experience greater climate risks associated with extreme El Niño events than seen at 1.5°C warming.”

    The research was based on five climate models that provided future scenarios past the year 2100.

    The models were run using the Intergovernmental Panel on Climate Change’s lowest emissions scenario (RCP2.6), which requires negative emissions late in the century.

    Director of the Centre for Southern Hemisphere Oceans Research and report co-author, Dr Wenju Cai, said that this research continues important work on the impacts of climate change on the El Niño-Southern Oscillation which is a significant driver of global climate.

    “The most severe previous extreme El Niño events occurred in 1982/83, 1997/98 and 2015/16, years associated with worldwide climate extremes,” Dr Cai said.

    “Extreme El Niño events occur when the usual El Niño Pacific rainfall centre is pushed eastward toward South America, sometimes up to 16,000 kilometres, causing massive changes in the climate. The further east the centre moves, the more extreme the El Niño.

    “This pulls rainfall away from Australia bringing conditions that have commonly resulted in intense droughts across the nation. During such events, other countries like India, Ecuador, and China have experienced extreme events with serious socio-economic consequences.”

    Dr Cai added that while previous research suggested that extreme La Niña events would double under a 4.5°C warming scenario, results here indicated that under a scenario of climate stabilisation (i.e. 1.5°C warming) there was little or no change to these La Niña events.

    The research was conducted by researchers at the Hobart based Centre for Southern Hemisphere Oceans Research, an international collaboration between CSIRO, Qingdao National Laboratory for Marine Science and Technology, the University of New South Wales, and the University of Tasmania.

    The National Environmental Science Programme’s Earth System and Climate Change Hub co-funded this research.

    See the full article here .

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    CSIRO, the Commonwealth Scientific and Industrial Research Organisation, is Australia’s national science agency and one of the largest and most diverse research agencies in the world.

     
  • richardmitnick 11:01 am on July 13, 2017 Permalink | Reply
    Tags: , Climate Change, , , The calving of a massive iceberg in Antarctica is not a sign of climate doom but it may weaken the remainder of the Larsen C ice shelf, What the trillion-tonne Larsen C iceberg means   

    From COSMOS: “What the trillion-tonne Larsen C iceberg means” 

    Cosmos Magazine bloc

    COSMOS

    13 July 2017
    Adrian Luckman

    The calving of a massive iceberg in Antarctica is not a sign of climate doom, but it may weaken the remainder of the Larsen C ice shelf.

    One of the largest icebergs ever recorded has just broken away from the Larsen C Ice Shelf in Antarctica. Over the past few years I’ve led a team that has been studying this ice shelf and monitoring change. We spent many weeks camped on the ice investigating melt ponds and their impact – and struggling to avoid sunburn thanks to the thin ozone layer. Our main approach, however, is to use satellites to keep an eye on things.

    ESA/Sentinal 1


    The SENTINEL-1 mission comprises a constellation of two polar-orbiting satellites, operating day and night performing C-band synthetic aperture radar imaging, enabling them to acquire imagery regardless of the weather.

    We’ve been surprised by the level of interest in what may simply be a rare but natural occurrence. Because, despite the media and public fascination, the Larsen C rift and iceberg “calving” is not a warning of imminent sea level rise, and any link to climate change is far from straightforward. This event is, however, a spectacular episode in the recent history of Antarctica’s ice shelves, involving forces beyond the human scale, in a place where few of us have been, and one which will fundamentally change the geography of this region.

    1
    The iceberg would barely fit inside Wales. Adrian Luckman / MIDAS, Author provided

    Ice shelves are found where glaciers meet the ocean and the climate is cold enough to sustain the ice as it goes afloat. Located mostly around Antarctica, these floating platforms of ice a few hundred meters thick form natural barriers which slow the flow of glaciers into the ocean and thereby regulate sea level rise. In a warming world, ice shelves are of particular scientific interest because they are susceptible both to atmospheric warming from above and ocean warming from below.

    2
    The ice shelves of the Antarctic peninsula. Note Larsen A and B have largely disappeared. AJ Cook & DG Vaughan, 2014, CC BY-SA

    Back in the 1890s, a Norwegian explorer named Carl Anton Larsen sailed south down the Antarctic Peninsula, a 1,000km long branch of the continent that points towards South America. Along the east coast he discovered the huge ice shelf which took his name.

    For the following century, the shelf, or what we now know to be a set of distinct shelves – Larsen A, B, C and D – remained fairly stable. However the sudden disintegrations [Science] of Larsen A and B in 1995 and 2002 respectively, and the ongoing speed-up [Geophysical Research Letters] of glaciers which fed them, focused scientific interest on their much larger neighbour, Larsen C, the fourth biggest ice shelf in Antarctica.

    This is why colleagues and I set out in 2014 to study the role of surface melt [Cambridge Core] on the stability of this ice shelf. Not long into the project, the discovery by our colleague, Daniela Jansen, of [The Cryosphere]a rift growing rapidly through Larsen C, immediately gave us something equally significant to investigate.

    Nature at work

    The development of rifts and the calving of icebergs is part of the natural cycle of an ice shelf. What makes this iceberg unusual is its size – at around 5,800 km² it’s the size of a small US state. There is also the concern that what remains of Larsen C will be susceptible to the same fate as Larsen B, and collapse almost entirely.

    3
    Larsen B once extended hundreds of kilometres over the ocean. Today, one of its glaciers runs straight into the sea. Armin Rose / shutterstock

    Our work has highlighted significant similarities [Nature Communications] between the previous behaviour of Larsen B and current developments at Larsen C, and we have shown that stability may be compromised. Others, however, are confident that Larsen C will remain stable [Nature Climate Change].

    What is not disputed by scientists is that it will take many years to know what will happen to the remainder of Larsen C as it begins to adapt to its new shape, and as the iceberg gradually drifts away and breaks up [The Conversation]. There will certainly be no imminent collapse, and unquestionably no direct effect on sea level because the iceberg is already afloat and displacing its own weight in seawater.

    This means that, despite much speculation [On The Verge], we would have to look years into the future for ice from Larsen C to contribute significantly to sea level rise. In 1995 Larsen B underwenta similar calving event [Nature Communications]. However, it took a further seven years of gradual erosion of the ice-front before the ice shelf became unstable enough to collapse, and glaciers held back by it were able to speed up [Geophysical Research Letters], and even then the collapse process may have depended on the presence of surface melt ponds [Geophysical Research Letters].

    Even if the remaining part of Larsen C were to eventually collapse, many years into the future, the potential sea level rise is quite modest [Journal of Geophysical Research]. Taking into account only the catchments of glaciers flowing into Larsen C, the total, even after decades, will probably be less than a centimetre.

    Is this a climate change signal?

    This event has also been widely but over-simplistically linked to climate change [The Guardian]. This is not surprising because notable changes in the earth’s glaciers and ice sheets are normally associated with rising environmental temperatures. The collapses of Larsen A and B have previously been linked to regional warming [Letters to Nature], and the iceberg calving will leave Larsen C at its most retreated position in records going back over a hundred years.

    However, in satellite images from the 1980s, the rift was already clearly a long-established feature, and there is no direct evidence to link its recent growth to either atmospheric warming, which is not felt deep enough within the ice shelf, or ocean warming, which is an unlikely source of change given that most of Larsen C has recently been thickening [Science]. It is probably too early to blame this event directly on human-generated climate change.

    See the full article here .

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  • richardmitnick 8:05 am on May 8, 2017 Permalink | Reply
    Tags: , Climate Change, , , JISUNG PARK   

    From Harvard: “Making sense of climate costs” 

    Harvard University
    Harvard University

    April 28, 2017
    Colin Durrant

    1
    JISUNG PARK
    PhD Candidate in Economics
    Department of Economics
    Harvard University
    1805 Cambridge St
    Cambridge, MA 02138


    Video by Joe Sherman & Kai-Jae Wang

    Growing up between Lawrence, Kan., and Seoul, South Korea, gave Jisung Park different and distinct insights into how humans and nature intersect. Park recalls as a young boy spending every waking hour exploring the Kansas outdoors. Still a youngster when he moved to Seoul, living in its dense, urban environment revealed the toll that industrialization exacts on air and water quality.

    “I was always acutely aware of how human beings and society both affect and are affected by the natural environment,” said Park, who will graduate in May with a Ph.D. in economics from the Harvard Graduate School of Arts and Sciences. “Through experiencing the diversity of living in such different places, I grew to appreciate how much commonality there is in the basic humanity that we share.”

    His introductory economics class in high school gave him an entirely new lens with which to view the world — and think about studying it. In his undergraduate coursework at Columbia University, Park recognized that economics could be a tool for generating a greater understanding of the intersection of humans and nature.

    After his Rhodes Scholarship at Oxford University, Park joined the environmental economics program at Harvard to focus specifically on how the impacts of climate change will affect human productivity and economic health.

    “He has broken new ground with his research on weather, climate, and human capital, and will soon be moving on to a great career as an innovative scholar,” said Robert Stavins, the Albert Pratt Professor of Business & Government at Harvard Kennedy School and director of the Harvard Environmental Economics Program.

    Park says the motivation for his research is the fundamental disconnect in the public’s mind between recognizing climate change as a problem in the abstract sense but not being able to relate to the immediate impacts that may already be affecting the local community or region.

    “I was frustrated by this phenomenon that climate change was becoming an issue that, unless you are an ardent environmentalist, you weren’t allowed to comment about or care about,” said Park. “I wanted to use language and tools of economics to try and quantify the more direct impacts of climate change on human beings and human economy, to try and make it a little more real.”

    At a time when much attention is on rising sea levels and extreme weather events, Park eagerly took on the challenge of developing a greater understanding of the correlation between long-term economic vitality and rising temperatures due to global warming. As one of the first grantees of the President’s Climate Change Solutions Fund, Park explored the affect heat stress will have on labor productivity. According to Park, a year with 10 or more 90-degree-plus days in the United States could reduce income or output per capita by 3 percent. For context, he points to the fact that the Great Recession led to a percentage drop in GDP of that magnitude.

    Park says the grant opened doors and allowed him to engage with a wide variety of research institutions inside and outside of Harvard, including presenting his research to the World Bank and New York City government agencies.

    “It’s good to know there is institutional support for interdisciplinary research like this and that the support comes close to the top,” Park said. “It speaks to the direction in which the university wants to move in terms of priorities.”

    While at Harvard, Park presented what New York Times columnist Nicholas Kristof called a “clever new working paper” exploring the impact of hotter temperatures on student test scores and academic performance in New York City schools. He found that students taking a test on a 90-degree day relative to a 72-degree day have a 12 percent higher likelihood of failing. “You may not have seen a polar bear but you’ve definitely been in a classroom that was hot,” said Park.

    Park brought with him from Oxford a podcast project called Sense & Sustainability that started as a series of conversations with fellow students on topics related to sustainability. At Harvard, the organization took off, receiving a Student Sustainability Grant from the Harvard Office for Sustainability and expanding to a lively blog and weekly meetings of undergraduate and graduate fellows to share ideas.

    “It’s hard to have conversations across disciplines but also very rewarding, because it forces you to think outside your disciplinary focus or bias,” said Park. “It’s amazing how different our conceptions are of what sustainability is, and it opened me up to the diversity of ways one can conceptualize sustainability.”

    Park will complete a postdoc at Harvard Kennedy School on climate policy, then join the faculty at UCLA as part of a joint public policy and public health program, where he will continue his research into the environmental determinants of economic mobility.

    “The more you look at direct economic impacts of climate change, the more it begins to become clear it will be disadvantaged segments of society — both within countries but also across the world — that are going to be disproportionately affected,” said Park. “Climate change is the ultimate global public good problem, and that certainly is a motivation for me.”

    See the full article here .

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    Harvard is the oldest institution of higher education in the United States, established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. It was named after the College’s first benefactor, the young minister John Harvard of Charlestown, who upon his death in 1638 left his library and half his estate to the institution. A statue of John Harvard stands today in front of University Hall in Harvard Yard, and is perhaps the University’s best known landmark.

    Harvard University has 12 degree-granting Schools in addition to the Radcliffe Institute for Advanced Study. The University has grown from nine students with a single master to an enrollment of more than 20,000 degree candidates including undergraduate, graduate, and professional students. There are more than 360,000 living alumni in the U.S. and over 190 other countries.

     
  • richardmitnick 6:59 am on April 25, 2017 Permalink | Reply
    Tags: , Climate Change, , Nile River   

    From MIT: “Nile faces greater variability” 

    MIT News

    MIT Widget

    MIT News

    April 24, 2017
    David L. Chandler

    1
    Researchers at MIT have found that climate change may drastically increase the variability in Nile’s annual output.

    Climate change could lead to overall increase in river flow, but more droughts and floods, study shows.

    The unpredictable annual flow of the Nile River is legendary, as evidenced by the story of Joseph and the Pharaoh, whose dream foretold seven years of abundance followed by seven years of famine in a land whose agriculture was, and still is, utterly dependent on that flow. Now, researchers at MIT have found that climate change may drastically increase the variability in Nile’s annual output.

    Being able to predict the amount of flow variability, and even to forecast likely years of reduced flow, will become ever more important as the population of the Nile River basin, primarily in Egypt, Sudan, and Ethiopia, is expected to double by 2050, reaching nearly 1 billion. The new study, based on a variety of global climate models and records of rainfall and flow rates over the last half-century, projects an increase of 50 percent in the amount of flow variation from year to year.

    The study, published in the journal Nature Climate Change, was carried out by professor of civil and environmental engineering Elfatih Eltahir and postdoc Mohamed Siam. They found that as a result of a warming climate, there will be an increase in the intensity and duration of the Pacific Ocean phenomenon known as the El Niño/La Niña cycle, which they had previously shown is strongly connected to annual rainfall variations in the Ethiopian highlands and adjacent eastern Nile basins. These regions are the primary sources of the Nile’s waters, accounting for some 80 percent of the river’s total flow.

    The cycle of the Nile’s floods has been “of interest to human civilization for millennia,” says Eltahir, the Breene M. Kerr Professor of Hydrology and Climate. Originally, the correlation he showed between the El Niño/La Niña cycle and Ethiopian rainfall had been aimed at helping with seasonal and short-term predictions of the river’s flow, for planning storage and releases from the river’s many dams and reservoirs. The new analysis is expected to provide useful information for much longer-term strategies for placement and operation of new and existing dams, including Africa’s largest, the Grand Ethiopian Renaissance Dam, now under construction near the Ethiopia-Sudan border.

    While there has been controversy about that dam, and especially about how the filling of its reservoir will be coordinated with downstream nations, Eltahir says this study points to the importance of focusing on the potential impacts of climate change and rapid population growth as the most significant drivers of environmental change in the Nile basin. “We think that climate change is pointing to the need for more storage capacity in the future,” he says. “The real issues facing the Nile are bigger than that one controversy surrounding that dam.”

    Using a variety of global circulation models under “business as usual” scenarios, assuming that major reductions in greenhouse gas emissions do not take place, the study finds that the changing rainfall patterns would likely lead to an average increase of the Nile’s annual flow of 10 to 15 percent. That is, it would grow from its present 80 cubic kilometers per year to about 92 or more cubic kilometers per year averaged over the 21st century, compared to the 20th century average.

    The findings also suggest that there will be substantially fewer “normal” years, with flows between 70 and 100 cubic kilometers per year. There will also be many more extreme years with flows greater than 100, and more years of drought. (Statistically, the variability is measured as the standard deviation of the annual flow rates, which is the number that is expected to see a 50 percent rise).

    The pattern has in fact played out over the last two years — 2015, an intense El Niño year, saw drought conditions in the Nile basin, while the La Niña year of 2016 saw high flooding. “It’s not abstract,” Eltahir says. “This is happening now.”

    As with Joseph’s advice to Pharaoh, the knowledge of such likely changes can help planners to be prepared, in this case by storing water in huge reservoirs to be released when it is really needed.

    “Too often we focus on how climate change might influence average conditions, to the exclusion of thinking about variability,” says Ben Zaitchik, an associate professor of earth and planetary sciences at Johns Hopkins University, who was not involved in this work. “That can be a real problem for a place like the Eastern Nile basin, where average rainfall and streamflow might increase with climate change, suggesting that water will be plentiful. But if variability increases as well, then there could be as frequent or more frequent stress events, and significant planning — in infrastructure or management strategies — might be required to ensure water security.”

    Already, Eltahir’s earlier work on the El Niño/La Niña correlation with Nile flow is making an impact. “It’s used operationally in the region now in issuing seasonal flood forecasts, with a significant lead time that gives water resources engineers enough time to react. Before, you had no idea,” he says adding that he hopes the new information will enable even better long-term planning. “By this work, we at least reduce some of the uncertainty.”

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    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

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  • richardmitnick 10:45 am on April 20, 2017 Permalink | Reply
    Tags: , Climate Change,   

    From NYT: “Is It O.K. to Tinker With the Environment to Fight Climate Change?” 

    New York Times

    The New York Times

    APRIL 18, 2017
    JON GERTNER

    Scientists are investigating whether releasing tons of particulates into the atmosphere might be good for the planet. Not everyone thinks this is a good idea.

    1

    For the past few years, the Harvard professor David Keith has been sketching this vision: Ten Gulfstream jets, outfitted with special engines that allow them to fly safely around the stratosphere at an altitude of 70,000 feet, take off from a runway near the Equator. Their cargo includes thousands of pounds of a chemical compound — liquid sulfur, let’s suppose — that can be sprayed as a gas from the aircraft. It is not a one-time event; the flights take place throughout the year, dispersing a load that amounts to 25,000 tons. If things go right, the gas converts to an aerosol of particles that remain aloft and scatter sunlight for two years. The payoff? A slowing of the earth’s warming — for as long as the Gulfstream flights continue.

    Keith argues that such a project, usually known as solar geoengineering, is technologically feasible and — with a back-of-the-envelope cost of under $1 billion annually — ought to be fairly cheap from a cost-benefit perspective, considering the economic damages potentially forestalled: It might do good for a world unable to cut carbon-dioxide emissions enough to prevent further temperature increases later this century.

    What surprised me, then, as Keith paced around his Harvard office one morning in early March, was his listing all the reasons humans might not want to hack the environment. “Actually, I’m writing a paper on this right now,” he said. Most of his thoughts were related to the possible dangers of trying to engineer our way out of a climate problem of nearly unimaginable scientific, political and moral complexity. Solar geoengineering might lead to what some economists call “lock-in,” referring to the momentum that a new technology, even one with serious flaws, can assume after it gains a foothold in the market. The qwerty keyboard is one commonly cited example; the internal combustion engine is another. Once we start putting sulfate particles in the atmosphere, he mused, would we really be able to stop?

    Another concern, he said, is “just the ethics about messing with nature.” Tall, wiry and kinetic, with thinning hair and a thick beard that gives him the look of the backcountry skier he is, Keith proudly showed me the framed badge that his father, a biologist, wore when he attended the landmark United Nations Conference on the Human Environment in Stockholm in 1972. Now 53, Keith has taken more wilderness trips — hiking, rock climbing, canoeing — than he can properly recall, and for their recent honeymoon, he and his wife were dropped off by helicopter 60 miles from the nearest road in northern British Columbia. “It was quite rainy,” he told me, “and that ended up making it even better.” So the prospect of intentionally changing the climate, he confessed, is not just unpleasant — “it initially struck me as nuts.”

    It still strikes him as a moral hazard, to use a term he borrows from economics. A planet cooled by an umbrella of aerosol particles — an umbrella that works by reflecting back into space, say, 1 percent of the sun’s incoming energy — might give societies less incentive to adopt greener technologies and radically cut carbon emissions. That would be disastrous, Keith said. The whole point of geoengineering is not to give us license to forget about the buildup of CO₂. It’s to lessen the ill effects of the buildup and give us time to transition to cleaner energy.

    Beyond these conceivable dangers, though, a more fundamental problem lurks: Solar geoengineering simply might not work. It has been a subject of intense debate among climate scientists for roughly a decade. But most of what we know about its potential effects derives from either computer simulations or studies on volcanic eruptions like that of Mount Pinatubo in 1991, which generated millions of tons of sunlight-scattering particulates and might have cooled the planet by as much as 0.5 degrees Celsius, or nearly 1 degree Fahrenheit. The lack of support for solar geoengineering’s efficacy informs Keith’s thinking about what we should do next. Actively tinkering with our environment — fueling up the Gulfstream jets and trying to cool things down — is not something he intends to try anytime soon, if ever. But conducting research is another matter.

    A decade ago, when Keith was among the few American scientists to advocate starting a geoengineering research program, he was often treated at science conferences as an outlier. “People would sort of inch away or, really, tell me I shouldn’t be doing this,” he said. Geoengineering was seen as a scientific taboo and Keith its dark visionary. “The preconception was that I was some kind of Dr. Strangelove figure,” he told me — “which I didn’t like.”

    Attitudes appear to have changed over the past few years, at least in part because of the continuing academic debates and computer-modeling studies. The National Academy of Sciences endorsed the pursuit of solar geoengineering research in 2015, a stance also taken in a later report by the Obama administration. A few influential environmental groups, like the Natural Resources Defense Council and the Environmental Defense Fund, now favor research.

    In the meantime, Keith’s own work at Harvard has progressed. This month, he is helping to start Harvard’s Solar Geoengineering Research Program, a broad endeavor that begins with $7 million in funding and intends to reach $20 million over seven years. One backer is the Hewlett Foundation; another is Bill Gates, whom Keith regularly advises on climate change. Keith is planning to conduct a field experiment early next year by putting particles into the stratosphere over Tucson.

    The new Harvard program is not merely intent on getting its concepts out of the lab and into the field, though; a large share of its money will also be directed to physical and social scientists at the university, who will evaluate solar geoengineering’s environmental dangers — and be willing to challenge its ethics and practicality. Keith told me, “It’s really important that we have a big chunk of the research go to groups whose job will be to find all the ways that it won’t work.” In other words, the technology that Keith has long believed could help us ease our predicament — “the nuclear option” for climate, as one opponent described it to me, to be considered only when all else has failed — will finally be investigated to see whether it is a reasonable idea. At the same time, it will be examined under the premise that it may in fact be a very, very bad one.

    Climate change already presents a demoralizing array of challenges — melting ice sheets and species extinctions — but the ultimate severity of its impacts depends greatly on how drastically technology and societies can change over the next few decades. The growth of solar and wind power in recent years, along with an apparent decrease in coal use, suggest that the global community will succeed in curtailing CO₂ emissions. Still, that may not happen nearly fast enough to avert some dangerous consequences. As Keith likes to point out, simply reducing emissions doesn’t reverse global warming. In fact, even if annual global CO₂ emissions decrease somewhat, the total atmospheric CO₂ may continue to increase, because the gas is so slow to dissipate. We may still be living with damaging amounts of atmospheric carbon dioxide a half-century from now, with calamitous repercussions. The last time atmospheric CO₂ levels were as elevated as they are today, three million years ago, sea levels were most likely 45 feet higher, and giant camels roamed above the Arctic Circle.

    Recently, I met with Daniel Schrag, who is the head of the Harvard University Center for the Environment, an interdisciplinary teaching and research department. Schrag, who helped recruit Keith to Harvard, painted a bleak picture of our odds of keeping global temperatures from rising beyond levels considered safe by many climate scientists. When you evaluate the time scales involved in actually switching our energy systems to cleaner fuels, Schrag told me, “the really depressing thing is you start to understand why any of these kinds of projections — for 2030 or 2050 — are absurd.” He went on: “Are they impossible? No. I want to give people hope, too. I’d love to make this happen. And we have made a lot of progress on some things, on solar, on wind. But the reality is we haven’t even started doing the hard stuff.”

    Schrag described any kind of geoengineering as “at best an imperfect solution that is operationally extremely challenging.” Yet to Schrag and Keith, the political and technical difficulties associated with a rapid transition to a zero-carbon-emissions world make it sensible to look into geoengineering research. There happens to be a number of different plans for how to actually do it, however — including the fantastical (pumping seawater onto Antarctica to combat sea-level rise) and the impractical (fertilizing oceans with iron to foster the growth of algae, which would absorb more CO₂). Some proposals involve taking carbon out of the air, using either immense plant farms or absorption machines. (Keith is involved with such sequestration technology, which faces significant hurdles in terms of cost and feasibility.) Another possible approach would inject salt crystals into clouds over the ocean to brighten them and cool targeted areas, like the dying Great Barrier Reef. Still, the feeling among Keith and his colleagues is that aerosols sprayed into the atmosphere might be the most economically and technologically viable approach of all — and might yield the most powerful global effect.

    It is not a new idea. In 2000, Keith published a long academic paper on the history of weather and climate modification, noting that an Institute of Rainmaking was established in Leningrad in 1932 and that American engineers began a cloud-seeding campaign in Vietnam a few decades later. A report issued in 1965 by President Lyndon B. Johnson’s administration called attention to the dangers of increasing concentrations of CO₂ and, anticipating Keith’s research, speculated that a logical response might be to change the albedo, or reflectivity, of the earth. To Keith’s knowledge, though, there have been only two actual field experiments so far. One, by a Russian scientist in 2009, released aerosols into the lower atmosphere via helicopter and appears to have generated no useful data. “It was a stunt,” Keith says. Another was a modest attempt at cloud brightening a few years ago by a team at the Scripps Institution of Oceanography at the University of California, San Diego.

    Downstairs from Keith’s Harvard office, there is a lab cluttered with students fiddling with pipettes and arcane scientific instruments. When I visited in early March, Zhen Dai, a graduate student who works with Keith, was engaged with a tabletop apparatus, a maze of tubes and pumps and sensors, meant to study how chemical compounds interact with the stratosphere. For the moment, Keith’s group is leaning toward beginning its field experiments with ice crystals and calcium carbonate — limestone — that has been milled to particles a half-micron in diameter, or less than 1/100th the width of a human hair. They may eventually try a sulfur compound too. The experiment is called Scopex, which stands for Stratospheric Controlled Perturbation Experiment. An instrument that can disperse an aerosol of particles — say, several ounces of limestone dust — will be housed in a gondola that hangs beneath a balloon that ascends to 70,000 feet. The whole custom-built contraption, whose two small propellers will be steered from the ground, will also include a variety of sensors to collect data on any aerosol plume. Keith’s group will measure the sunlight-scattering properties of the plume and evaluate how its particles interact with atmospheric gases, especially ozone. The resulting data will be used by computer models to try to predict larger-scale effects.

    But whether a scientist should be deliberately putting foreign substances into the atmosphere, even for a small experiment like this, is a delicate question. There is also the difficulty of deciding on how big the atmospheric plumes should get. When does an experiment become an actual trial run? Ultimately, how will the scientists know if geoengineering really works without scaling it up all the way?

    Keith cites precedents for his thinking: a company that scatters cremation ashes from a high-altitude balloon, and jet engines, whose exhaust contains sulfates. But the crux of the problem that Harvard’s Solar Geoengineering Research Program wrestles with is intentionality. Frank Keutsch, a professor of atmospheric sciences at Harvard who is designing and running the Scopex experiments with Keith, told me: “This effort with David is very different from all my other work, because for those other field experiments, we’ve tried to measure the atmosphere and look at processes that are already there. You’re not actually changing nature.” But in this case, Keutsch agrees, they will be.

    During one of our conversations, Keith suggested that I try to flip my thinking for a moment. “What if humanity had never gotten into fossil fuels,” he posed, “and the world had gone directly to generating energy from solar or wind power?” But then, he added, what if in this imaginary cleaner world there was a big natural seep of a heat-trapping gas from within the earth? Such events have happened before. “It would have all the same consequences that we’re worried about now, except that it’s not us doing the CO₂ emissions,” Keith said. In that case, the reaction to using geoengineering to cool the planet might be one of relief and enthusiasm.

    In other words, decoupling mankind’s actions — the “sin,” as Keith put it, of burning fossil fuels — from our present dilemma can demonstrate the value of climate intervention. “No matter what, if we emit CO₂, we are hurting future generations,” Keith said. “And it may or may not be true that doing some solar geo would over all be a wise thing to do, but we don’t know yet. That’s the reason to do research.”

    There are risks, undeniably — some small, others potentially large and terrifying. David Santillo, a senior scientist at Greenpeace, told me that some modeling studies suggest that putting aerosols in the atmosphere, which might alter local climates and rain patterns and would certainly affect the amount of sunlight hitting the earth, could have a significant impact on biodiversity. “There’s a lot more we can do in theoretical terms and in modeling terms,” Santillo said of the Harvard experiments, “before anyone should go out and do this kind of proof-of-concept work.” Alan Robock, a professor of atmospheric sciences at Rutgers, has compiled an exhaustive list of possible dangers. He thinks that small-scale projects like the Scopex experiment could be useful, but that we don’t know the impacts of large-scale geoengineering on agriculture or whether it might deplete the ozone layer (as volcanic eruptions do). Robock’s list goes on from there: Solar geoengineering would probably reduce solar-electricity generation. It would do nothing to reduce the increasing acidification of the oceans, caused by seawater absorbing carbon dioxide. A real prospect exists, too, that if solar geoengineering efforts were to stop abruptly for any reason, the world could face a rapid warming even more dangerous than what’s happening now — perhaps too fast for any ecological adaptation.

    Keith is well aware of Robock’s concerns. He also makes the distinction that advocating research is not the same as advocating geoengineering. But the line can blur. Keith struck me as having a fair measure of optimism that his research can yield insights into materials and processes that can reduce the impacts of global warming while averting huge risks. For instance, he is already encouraged by computer models that suggest the Arctic ice cap, which has shrunk this year to the smallest size observed during the satellite era, could regrow under cooler conditions brought on by light-scattering aerosols. He also believes that the most common accusation directed against geoengineering — that it might disrupt precipitation patterns and lead to widespread droughts — will prove largely unfounded.

    But Keith is not trained as an atmospheric scientist; he’s a hands-on physicist-engineer who likes to take machinery apart. There are deep unknowns here. Keutsch, for one, seems uncertain about what he will discover when the group actually tries spraying particulates high above the earth. The reduction of sunlight could adversely affect the earth’s water cycle, for example. “It really is unclear to me if this approach is feasible,” he says, “and at this point we know far too little about the risks. But if we want to know whether it works, we have to find out.”

    Finally, what if something goes wrong either in research or in deployment? David Battisti, an atmospheric scientist at the University of Washington, told me, “It’s not obvious to me that we can reduce the uncertainty to anywhere near a tolerable level — that is, to the level that there won’t be unintended consequences that are really serious.” While Battisti thought Keith’s small Scopex experiment posed little danger — “The atmosphere will restore itself,” he said — he noted that the whole point of the Harvard researchers’ work is to determine whether solar geoengineering could be done “forever,” on a large-scale, round-the-clock basis. When I asked Battisti if he had issues with going deeper into geoengineering research, as opposed to geoengineering itself, he said: “Name a technology humans have developed that they haven’t used. I can’t think of any. So we can work on this for sure. But we are in this dilemma: Once we do develop this technology, it will be tempting to use it.”

    Suppose Keith’s research shows that solar geoengineering works. What then? The world would need to agree where to set the global thermostat. If there is no consensus, could developed nations impose a geoengineering regimen on poorer nations? On the second point, if this technology works, it would arguably be unethical not to use it, because the world’s poorest populations, facing drought and rising seas, may suffer the worst effects of a changing climate.

    In recent months, a group under the auspices of the Carnegie Council in New York, led by Janos Pasztor, a former United Nations climate official, has begun to work through the thorny international issues of governance and ethics. Pasztor told me that this effort will most likely take four years. And it is not lost on him — or anyone I spoke with in Keith’s Harvard group — that the idea of engineering our environment is taking hold as we are contemplating the engineering of ourselves through novel gene-editing technologies. “They both have an effect on shaping the pathway where human beings are now and where will they be,” says Sheila Jasanoff, a professor of science and technology studies at Harvard who sometimes collaborates with Keith. Jasanoff also points out that each technology potentially enables rogue agents to act without societal consent.

    This is a widespread concern. We might reach a point at which some countries pursue geoengineering, and nothing — neither costs nor treaties nor current technologies — can stop them. Pasztor sketched out another possibility to me: “You could even have a nightmare scenario, where a country decides to do geoengineering and another country decides to do counter-geoengineering.” Such a countermeasure could take the form of an intentional release of a heat-trapping gas far more potent than CO₂, like a hydrochlorofluorocarbon. One of Schrag’s main concerns, in fact, is that geoengineering a lower global temperature might preserve ecosystems and limit sea-level rise while producing irreconcilable geopolitical frictions. “One thing I can’t figure out,” he told me, “is how do you protect the Greenland ice sheet and still have Russia have access to its northern ports, which they really like?” Either Greenland and Siberia will melt, or perhaps both can stay frozen. You probably can’t split the difference.

    For the moment, and perhaps for 10 or 20 years more, these are mere hypotheticals. But the impacts of climate change were once hypotheticals, too. Now they’ve become possibilities and probabilities. And yet, as Tom Ackerman, an atmospheric scientist at the University of Washington, said at a recent discussion among policy makers that I attended in Washington: “We are doing an experiment now that we don’t understand.” He was not talking about geoengineering; he was observing that the uncertainty about the potential risks of geoengineering can obscure the fact that there is uncertainty, too, about the escalating disasters that may soon result from climate change.

    His comment reminded me of a claim made more than a half-century ago, long before the buildup of CO₂ in the atmosphere had become the central environmental and economic problem of our time. Two scientists, Roger Revelle and Hans Suess, wrote in a scientific paper, “Human beings are now carrying out a large-scale geophysical experiment of a kind that could not have happened in the past nor be reproduced in the future.”

    If anything could sway a fence-sitter to consider whether geoengineering research makes sense, perhaps it is this. The fact is, we are living through a test already.

    See the full article here .

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  • richardmitnick 8:24 am on April 19, 2017 Permalink | Reply
    Tags: Climate Change, Climate Change Reroutes a Yukon River in a Geological Instant, , , , Kaskawulsh Glacier, , Slims River Valley   

    From NYT: “Climate Change Reroutes a Yukon River in a Geological Instant” 

    New York Times

    The New York Times

    APRIL 17, 2017
    JOHN SCHWARTZ

    1
    An aerial view of the ice canyon that now carries meltwater from the Kaskawulsh Glacier, on the right, away from the Slims River. “River piracy” refers to one river capturing and diverting the flow of another. Credit Dan Shugar/University of Washington-Tacoma

    In the blink of a geological eye, climate change has helped reverse the flow of water melting from a glacier in Canada’s Yukon, a hijacking that scientists call “river piracy.”

    This engaging term refers to one river capturing and diverting the flow of another. It occurred last spring at the Kaskawulsh Glacier, one of Canada’s largest, with a suddenness that startled scientists.

    A process that would ordinarily take thousands of years — or more — happened in just a few months in 2016.

    Much of the meltwater from the glacier normally flows to the north into the Bering Sea via the Slims and Yukon Rivers. A rapidly retreating and thinning glacier — accelerated by global warming — caused the water to redirect to the south, and into the Pacific Ocean.

    Last year’s unusually warm spring produced melting waters that cut a canyon through the ice, diverting more water into the Alsek River, which flows to the south and on into Pacific, robbing the headwaters to the north.

    2
    Jim Best, a researcher, measuring water levels on the lower-flowing Slims River in early September. Credit Dan Shugar/University of Washington-Tacoma

    The scientists concluded that the river theft “is likely to be permanent.”

    Daniel Shugar, an assistant professor of geoscience at the University of Washington-Tacoma, and colleagues described the phenomenon in a paper published on Monday in the journal Nature Geoscience.

    River piracy has been identified since the 19th century by geologists, and has generally been associated with events such as tectonic shifts and erosion occurring thousands or even millions of years ago. Those earlier episodes of glacial retreat left evidence of numerous abandoned river valleys, identified through the geological record.

    In finding what appears to be the first example of river piracy observed in modern times, Professor Shugar and colleagues used more recent technology, including drones, to survey the landscape and monitor the changes in the water coursing away from the Kaskawulsh Glacier.

    2
    Kaskawulsh glacier junction from air
    29 August 2014
    Author Gstest

    The phenomenon is unlikely to occur so dramatically elsewhere, Professor Shugar said in a telephone interview, because the glacier itself was forming a high point in the landscape and serving as a drainage divide for water to flow one way or another. As climate change causes more glaciers to melt, however, he said “we may see differences in the river networks and where rivers decide to go.”

    Changes in the flow of rivers can have enormous consequences for the landscape and ecosystems of the affected areas, as well as water supplies. When the shift abruptly reduced water levels in Kluane Lake, the Canadian Broadcasting Corporation reported, it left docks for lakeside vacation cabins — which can be reached only by water — high and dry.

    The riverbed of the Slims River basin, now nearly dry, experienced frequent and extensive afternoon dust storms through the spring and summer of last year, the paper stated.

    3
    The ice-walled canyon at the terminus of the Kaskawulsh Glacier, with recently collapsed ice blocks. This canyon now carries almost all meltwater from the toe of the glacier down the Kaskawulsh Valley and toward the Gulf of Alaska. Credit Jim Best/University of Illinois

    The impacts of climate change, like sea level rise or the shrinkage of a major glacier, are generally measured over decades, not months as in this case. “It’s not something you could see if you were just standing on the beach for a couple of months,” Professor Shugar said.

    The researchers concluded that the rerouted flow from the glacier shows that “radical reorganizations of drainage can occur in a geologic instant, although they may also be driven by longer-term climate change.” Or, as a writer for the CBC put it in a story about the phenomenon last year, “It’s a reminder that glacier-caused change is not always glacial-paced.”

    4
    Looking up the Slims River Valley, from the south end of Kluane Lake. The river used to flow down the valley from the Kaskawulsh glacier. (Sue Thomas)

    The underlying message of the new research is clear, said Dr. Shugar in a telephone interview. “We may be surprised by what climate change has in store for us — and some of the effects might be much more rapid than we are expecting.”

    The Nature Geoscience paper is accompanied by an essay from Rachel M. Headley, an assistant professor of geoscience and glacier expert at the University of Wisconsin-Parkside.

    “That the authors were able to capture this type of event almost as it was happening is significant in and of itself,” she said in an interview via email. As for the deeper significance of the incident, she said, “While one remote glacial river changing its course in the Yukon might not seem like a particularly big deal, glacier melt is a source of water for many people, and the sediments and nutrients that glacier rivers carry can influence onshore and offshore ecological environments, as well as agriculture.”

    Her article in Nature Geoscience concludes that this “unique impact of climate change” could have broad consequences. “As the world warms and more glaciers melt, populations dependent upon glacial meltwater should pay special attention to these processes.”

    Another glacier expert not involved in the research, Brian Menounos of the University of Northern British Columbia, said that while glaciers have waxed and waned as a result of natural forces over the eons, the new paper and his own research underscore the fact that the recent large-scale retreat of glaciers shows humans and the greenhouse gases they produce are reshaping the planet. “Clearly, we’re implicated in many of those changes,” he said.

    See the full article here .

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