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  • richardmitnick 7:14 am on August 21, 2015 Permalink | Reply
    Tags: , , Climate Change,   

    From The Conversation: “How much has global warming worsened California’s drought? Now we have a number” 

    Conversation
    The Conversation

    August 20, 2015
    Park Williams, Assistant Research Professor of Bioclimatology at Columbia University

    With each passing year, human-caused global warming bullies California for more water. Each year, the heat squeezes more moisture from soils and ecosystems.

    This is because, as the atmosphere warms, its demand for moisture rises. Just as a puddle evaporates more quickly on a warm day, soils dry out more quickly during warmer years, which are becoming increasingly frequent in most locations globally.

    Currently, California is in the grips of a severe drought, which motivated my colleagues and me to conduct a study to determine how much of this drought can be blamed on natural climate variability. And how much can be blamed on the global warming shakedown? Our answer is 8-27%.

    This finding, done using a model built on historical data, sheds light on California’s future and the effect higher temperatures have on the natural forces that drive California’s droughts.

    California of buckets

    Global warming is an emerging background effect on the year-to-year variations in drought caused by natural climate variations, such as El Niño and La Niña. This is especially true in California, where year-to-year precipitation varies wildly.

    4
    The 1997–98 El Niño observed by TOPEX/Poseidon. The white areas off the Tropical Western coasts of northern South and all Central America as well as along the Central-eastern equatorial and Southeastern Pacific Ocean indicate the pool of warm water.

    6
    Sea surface skin temperature anomalies in November 2007 showing La Niña conditions

    NASA Topex Poseiden
    TOPEX/Poseidon

    During most years, when natural climate variations cause wet or near-average conditions, the demands of the increasingly greedy atmosphere are still met with relative ease. During the last few years, however, natural climate variations have caused precipitation totals to be low and temperatures to be high. Human-caused warming, meanwhile, demands additional atmospheric moisture, at a time when water resources for natural and human systems are already in short supply.

    1
    These maps rank the three-year drought severity during 2012-2014 compared to all other consecutive three-year periods since 1901. The map on the left is calculated from the observed climate records. The map on the right is calculated after removing the global warming trend from the temperature records. Park Williams, Author provided

    Unlike natural climate variation, which only sometimes produces extreme conditions, the amount of additional moisture demanded by the atmosphere due to global warming increases each year as the concentration of atmospheric carbon dioxide rises ever higher. The squeeze that global warming is putting on California’s water balance is therefore becoming increasingly detectable.

    My colleagues and I quantified the effect of global warming on the recent California drought using a computational soil-moisture accounting approach. In this approach, we treat California as if it is a grid of 24,000 buckets laid side by side, each about seven square miles in area, and we simulate monthly changes in the amount of water held in each bucket from 1901 through 2014.

    Precipitation causes the buckets to fill up and potentially overflow, and evaporation causes the buckets to empty out. We calculated the evaporation from monthly records of temperature, humidity, wind speed and net radiation. Annual changes in the water content of the buckets during the summer months indicate annual changes in California water balance and can therefore be evaluated to determine the severity of the current California drought.

    Dry weather versus higher temps

    Because these drought calculations are all done mathematically using historical climate data, we can repeat our calculations over and over again while holding certain variables constant. This method allows us to isolate the relative contributions of specific climate processes, such as a lack of precipitation or the occurrence of extreme heat to the current California drought.

    Performing these calculations, we find that about 70% of the California drought severity during 2012-2014 was attributable to a lack of precipitation and the other 30% is attributable to increased atmospheric evaporative demand, which was mainly driven by very warm temperatures.

    3
    Change in California’s annual temperature and atmospheric evaporative demand during 1896-2014. The grey lines are the observed annual records and the smooth dark red lines are the trends caused by global warming (averaged across the various global warming trends we considered). Values in these graphs indicate departures from the 1931-1990 mean conditions. Park Williams, Author provided

    We next calculated how much of this temperature effect on drought was due to human-caused global warming and how much was due to natural temperature variability. We determined this by repeating our calculations using temperature records that exclude year-to-year temperature variations and only contain the long-term warming trend.

    We found that half to two-thirds of the temperature influence on drought conditions during 2012-2014 can be blamed on the warming trend, depending on the climate datasets considered. In other words, in the absence of global warming, the recent drought would have been approximately 15-20% less severe.

    Running the numbers

    It is important to acknowledge that we cannot be positive what portion of the long-term warming trend in California is related to human-caused global warming versus natural climate variability, so there is a fairly wide range of uncertainty surrounding the 15-20% estimate.

    4
    Higher temperatures are contributing to an active forest fire season in the West. Mike McMillan – USFS, CC BY-NC

    For example, has the effect of global warming on the California drought been steadily rising each year? Or has the effect increased in recent decades due to accelerating greenhouse gas concentrations? Or did regulations to remove air pollutants in the latter half of the twentieth century affect the warming rate due to increasing greenhouse gases?

    To address this uncertainty, we considered four alternate long-term warming trends, derived from actual temperature measurements and from temperature records simulated by climate models. Collectively, these warming scenarios are very likely to encompass the full range of possibilities. Considering the range of warming trends and all combinations of climate datasets used in this study, we concluded that global warming contributed between 8% and 27% to the severity of 2012-2014 California drought.

    Natural variability still dominant

    This result means that global warming is already having an important impact on California drought, but also that natural climate variability is still dominant.

    During 2012-2014, naturally low precipitation totals and high temperatures were mainly caused by a persistent high pressure system off the US west coast that blocked storms from making landfall in California. Combined with the increased evaporative demand due to global warming, this naturally occurring drought event produced record, or near record, drought throughout much of California.

    While there have been other three-year periods in the past when state-wide drought severity has been similar to that observed in 2012-2014, drought conditions during 2012-2014 have received much more attention than previous droughts partly because of where the most intense conditions were focused. Record-breaking drought conditions occurred in California’s Central Valley, which is important for agriculture, the southern Sierra Nevada Mountains, which is important for human water resources, and the southern and central coastal areas, which is where a large proportion of the population resides.

    Given that natural climate variability still dictates when the dry and wet periods occur in California, it is highly likely that wet conditions will return to the state in the next few years.

    Also because of natural climate variability, drought conditions are sure to return again and again, and each time the atmospheric bully and its high temperatures will demand an extra moisture payment, increasingly enhancing the likelihood of severe droughts with increasing duration. If California finds itself struggling with this drought, serious planning needs to take place in order to be resilient to a future where it’s increasingly likely that the current drought will look like child’s play.

    See the full article here.

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    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 10:31 am on August 13, 2015 Permalink | Reply
    Tags: , , Climate Change   

    From Brown: “As days warm, emergency visits, deaths rise” 

    Brown University
    Brown University

    August 13, 2015
    David Orenstein

    1
    Climate change and a hotter Rhode Island

    A new study that projects an increase in deaths and emergency visits in Rhode Island as climate change pushes summertime temperatures higher by the end of the century, has also revealed a finding of more immediate public health concern: Even in the present day, when temperatures rise above 75 degrees there is a noticeable increase in medical distress among state residents of all ages.

    The study by researchers at Brown University and the Rhode Island Department of Health is based on a detailed statistical analysis of emergency department visits, deaths, weather data, and possibly confounding factors (such as ozone) from recent years. The researchers could tell from the records whether emergency doctors thought a patient’s condition was related to heat or dehydration.

    “Our primary finding is that as temperatures increase, the number of emergency room visits and deaths increase,” said Samantha Kingsley, a Brown University public health graduate student and lead author of the study in the journal Environmental Health Perspectives. “But people were going to the hospital for heat-related reasons at temperatures below what we would typically consider extreme.”

    For example, researchers found that while the rate of heat-related ED visits jumped only 3.3 percent on days with a high of 75 degrees vs. days with a high of 65, it rocketed up 23.9 percent on days with a high of 85 degrees vs. 75. Overall temperature began to play an independent role in increasing ED visits starting at about 75 degrees.

    Meanwhile, the state’s death rate was 4 percent higher on a typical 85-degree day vs. a typical 75-degree day. Like ED visits, deaths appear to rise as high temperatures do, even at temperatures that many people would not consider extreme.

    2
    Emerging emergencies In the worst case considered (a 10-degree rise by 2099), summer heat-related emergency department visits would increase by about 25 percent. Charts: Wellenius Lab/Brown University

    “People should be aware that heat represents a significant public health threat,” said Gregory Wellenius, associate professor of epidemiology at Brown and the study’s senior author. “We do need to take heat seriously as a public health risk, even if there isn’t a heat warning.”

    Notably the strongest association between heat-related ED visits and higher temperature was not among senior citizens, but among Rhode Islanders aged 18-64. Many could be workers who remain outside on hot days, perhaps when it isn’t so safe.

    “Everybody believes that heat is dangerous but not for them,” Wellenius said. “One of the messages is that this is really across the age spectrum. Heat remains one of the leading causes of weather-related deaths.”

    Further in the future

    The finding that ED visits and deaths are greater on warmer days, even if temperatures are only in the 70s or 80s, suggests that distress from the heat may become even more common as temperatures rise as a result of global warming.

    To investigate that possibility, the researchers projected how much greater ED visits and mortality would be if the current Rhode Island population were living with the increased temperatures forecast by two standard models of global warming — one with a 6-degree rise by the end of the century and the other with a 10-degree rise. Their estimates use the models’ temperature forecasts for two ranges of years: 2046-2053 and 2092-2099.

    They project that if days became 10 degrees hotter by the end of the century, as in the hotter of the two models, the state’s summertime death rate would rise by about 1.5 percent (about 80 more deaths each summer) and the rate of heat-related emergency department visits would increase by about 25 percent (from about 6,000 to about 7,500 each summer).

    In both time periods and each scenario of warming temperatures, deaths and ED visits among Rhode Islanders would be higher. For example, even with the 2046-2053 temperatures forecast by the milder of the two models, the rate of heat-related ED visits is still estimated to rise by about 5 percent and the rate of deaths rises by about 0.6 percent.

    3
    Increased mortality. Warmer temperatures could increase the death rate in Rhode Island by more than 1.5 percent by the end of the century, under the warmer of two climate change models.

    By applying the effects of future temperatures to the current Rhode Island population, the study does not account for any of the possibly mitigating or exacerbating factors that could occur in the future. Improvements in technology or simply better education about of the health effects of heat could allow Rhode Islanders to tolerate better the higher temperatures of the future.

    Given the already apparent increase in ED visits and deaths on warmer days today, Kingsley said, people may want to pay more attention to the health risks of heat even as this summer runs its course.

    “Not even projecting into the future, it’s important for people to be aware of heat, and not just above 100 degrees,” Kingsley said. “Be prepared for any outdoor activities: Pack water bottles, stay hydrated. Get into air-conditioned environments at some point to cool down.”

    In addition to Kingsley and Wellenius, the study’s other authors are Melissa Eliot, Julia Gold, and Robert Vanderslice.

    The Centers for Disease Control and Prevention (grant 5UE1EH001040), the National Institute of Environmental Health Sciences (grant R01ES020871), and the Institute at Brown for Environment and Society funded the study.

    See the full article here.

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    Welcome to Brown

    Brown U Robinson Hall
    Located in historic Providence, Rhode Island and founded in 1764, Brown University is the seventh-oldest college in the United States. Brown is an independent, coeducational Ivy League institution comprising undergraduate and graduate programs, plus the Alpert Medical School, School of Public Health, School of Engineering, and the School of Professional Studies.

    With its talented and motivated student body and accomplished faculty, Brown is a leading research university that maintains a particular commitment to exceptional undergraduate instruction.

    Brown’s vibrant, diverse community consists of 6,000 undergraduates, 2,000 graduate students, 400 medical school students, more than 5,000 summer, visiting and online students, and nearly 700 faculty members. Brown students come from all 50 states and more than 100 countries.

    Undergraduates pursue bachelor’s degrees in more than 70 concentrations, ranging from Egyptology to cognitive neuroscience. Anything’s possible at Brown—the university’s commitment to undergraduate freedom means students must take responsibility as architects of their courses of study.

     
  • richardmitnick 1:06 pm on August 6, 2015 Permalink | Reply
    Tags: , Climate Change,   

    From NASA: “NASA Releases Detailed Global Climate Change Projections” 

    NASA

    NASA

    Aug. 6, 2015
    Editor: Karen Northon

    Steve Cole
    Headquarters, Washington
    202-358-0918
    stephen.e.cole@nasa.gov

    Darryl Waller
    Ames Research Center, Moffett Field, Calif.
    650-604-4789
    darryl.e.waller@nasa.gov

    1
    The new NASA global data set combines historical measurements with data from climate simulations using the best available computer models to provide forecasts of how global temperature (shown here) and precipitation might change up to 2100 under different greenhouse gas emissions scenarios. Credits: NASA

    NASA has released data showing how temperature and rainfall patterns worldwide may change through the year 2100 because of growing concentrations of greenhouse gases in Earth’s atmosphere.

    The dataset, which is available to the public, shows projected changes worldwide on a regional level in response to different scenarios of increasing carbon dioxide simulated by 21 climate models. The high-resolution data, which can be viewed on a daily timescale at the scale of individual cities and towns, will help scientists and planners conduct climate risk assessments to better understand local and global effects of hazards, such as severe drought, floods, heat waves and losses in agriculture productivity.

    “NASA is in the business of taking what we’ve learned about our planet from space and creating new products that help us all safeguard our future,” said Ellen Stofan, NASA chief scientist. “With this new global dataset, people around the world have a valuable new tool to use in planning how to cope with a warming planet.”

    The new dataset is the latest product from the NASA Earth Exchange(NEX), a big-data research platform within the NASA Advanced Supercomputing Center at the agency’s Ames Research Center in Moffett Field, California. In 2013, NEX released similar climate projection data for the continental United States that is being used to quantify climate risks to the nation’s agriculture, forests, rivers and cities.

    “This is a fundamental dataset for climate research and assessment with a wide range of applications,” said Ramakrishna Nemani, NEX project scientist at Ames. “NASA continues to produce valuable community-based data products on the NEX platform to promote scientific collaboration, knowledge sharing, and research and development.”

    This NASA dataset integrates actual measurements from around the world with data from climate simulations created by the international Fifth Coupled Model Intercomparison Project. These climate simulations used the best physical models of the climate system available to provide forecasts of what the global climate might look like under two different greenhouse gas emissions scenarios: a “business as usual” scenario based on current trends and an “extreme case” with a significant increase in emissions.

    The NASA climate projections provide a detailed view of future temperature and precipitation patterns around the world at a 15.5 mile (25 kilometer) resolution, covering the time period from 1950 to 2100. The 11-terabyte dataset provides daily estimates of maximum and minimum temperatures and precipitation over the entire globe.

    NEX is a collaboration and analytical platform that combines state-of-the-art supercomputing, Earth system modeling, workflow management and NASA remote-sensing data. Through NEX, users can explore and analyze large Earth science data sets, run and share modeling algorithms and workflows, collaborate on new or existing projects and exchange workflows and results within and among other science communities.

    NEX data and analysis tools are available to the public through the OpenNEX project on Amazon Web Services. OpenNEX is a partnership between NASA and Amazon, Inc., to enhance public access to climate data, and support planning to increase climate resilience in the U.S. and internationally. OpenNEX is an extension of the NASA Earth Exchange in a public cloud-computing environment.

    NASA uses the vantage point of space to increase our understanding of our home planet, improve lives, and safeguard our future. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term data records. The agency freely shares this unique knowledge and works with institutions around the world to gain new insights into how our planet is changing.

    Additional information about the new NASA climate projection dataset is available at:

    https://nex.nasa.gov/nex/projects/1356/

    The dataset is available for download at:

    https://cds.nccs.nasa.gov/nex-gddp/

    OpenNEX information and training materials are available at:

    http://nex.nasa.gov/opennex

    For more information about NASA’s Earth science activities, visit:

    http://www.nasa.gov/earth

    See the full article here.

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    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

     
  • richardmitnick 7:23 am on August 4, 2015 Permalink | Reply
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    From phys.org: “End-of-century Manhattan climate index to resemble Oklahoma City today” 

    physdotorg
    phys.org

    August 4, 2015
    Carnegie Institution for Science

    1
    View from Midtown Manhattan, facing south toward Lower Manhattan

    Climate change caused by greenhouse gas emissions will alter the way that Americans heat and cool their homes. By the end of this century, the number of days each year that heating and air conditioning are used will decrease in the Northern states, as winters get warmer, and increase in Southern states, as summers get hotter, according to a new study from a high school student, Yana Petri, working with Carnegie’s Ken Caldeira. It is published by Scientific Reports.

    “Changes in outdoor temperatures have a substantial impact on energy use inside,” Caldeira explained. “So as the climate changes due to greenhouse gases in the atmosphere, the amount of energy we use to keep our homes comfortable will also change.”

    Using results from established climate models, Petri, under Caldeira’s supervision, calculated the changes in the number of days over the last 30 years when U.S. temperatures were low enough to require heating or high enough to require air conditioning in order to achieve a comfort level of 65 degrees Fahrenheit. She also calculated projections for future days when heating or air conditioning would be required to maintain the same comfort level if current trends in greenhouse gas emissions continue unchecked.

    Looking forward toward the end of this century, her calculations found that Washington state will have the smallest increase in air conditioning-required days and southern Texas will have the largest increase. Likewise, upper North Dakota, Minnesota, and Maine would have the largest decrease in heating-required days and southern Florida would have the smallest decrease.

    Petri then took this inquiry one step further and looked at a sum of heating-required days and cooling-required days in different regions both in the past and in future projection, to get a sense of changes in the overall thermal comfort of different areas.

    “No previous study has looked at climate model projections and tried to develop an index of overall thermal comfort, which is quite an achievement,” Caldeira said.

    Today, the city with the minimum combined number of heating- and cooling-required days, in other words the place with the most-optimal outdoor comfort level, is San Diego. But the model projected that in the same future time frame, 2080-2099, the climate would shift so that San Francisco would take its place as the city with the most-comfortable temperatures.

    Other changes predicted by the model are that the amount of heating and cooling required in New York City in the future will be similar to that used in Oklahoma City today. By this same measure, Seattle is projected to resemble present day San Jose, and Denver to become more like Raleigh, NC, is today.

    See the full article here.

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    About Phys.org in 100 Words

    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

     
  • richardmitnick 10:52 am on August 2, 2015 Permalink | Reply
    Tags: , Climate Change,   

    From live science- “Drought Toll: California Now Missing 1 Year’s Worth of Rain” 

    Livescience

    July 31, 2015
    Andrea Thompson

    Temp 0
    California’s accumulated precipitation debt from 2012 to 2014 shown as a percent change from the 17-year average using the TRMM mission’s multi-satellite observations. Credit: Goddard’s Scientific Visualization Studio

    The amount of rain that California has missed out on since the beginning of its record-setting drought in 2012 is about the same amount it would see, on average, in a single year, a new study has concluded.

    The study’s researchers pin the reason for the lack of rains, as others have, on the absence of the intense rainstorms ushered in by so-called atmospheric rivers, the ribbons of very moist air that can funnel water vapor from the tropics to California during its winter rainy season.

    Overall, the study, accepted for publication in the Journal of Geophysical Research – Atmospheres, found that California experiences multi-year dry periods, like the current one, and then periods where rains can vary by 30 percent from year to year. Those wet and dry years typically cancel each other out.

    The El Niño-Southern Oscillation, one phase of which has ushered in some of the state’s wettest years, only accounts for about 6 percent of overall precipitation variability, the researchers found.

    Drought began creeping across the California landscape in 2012 and has continued to mushroom year after year as winter rains and snows were much diminished. The atmospheric rivers that normally funnel in moisture-laden air were thwarted by a persistent area of high pressure that blocked them from reaching California. This winter, precipitation that did manage to fall mostly did so as rains thanks to record-high temperatures linked to extremely warm waters off the coast, leaving the snowpack at record low levels.

    The new study looked at satellite measurements of rainfall from NASA’s Tropical Rainfall Measuring Mission(TRMM) satellite, as well as a recreated climate record that used both observations and model data to gauge how much California’s annual precipitation varied and how much it was in the hole after four years of drought.

    The researchers found that in an average year, the state sees about 20 inches of rain; it turns out that’s also about the amount of missing rain since 2012.

    To dig out of the drought in just one winter, the state would have to see 200 percent of its normal yearly rain, to cover both that year’s rain and make up the missing amount.

    That wet a winter isn’t very likely happen, Daniel Swain, a PhD student at Stanford University, said in an email. And if it did occur, it would mean major flooding, he added. Swain wasn’t involved with the new research.

    The study also looked at another recent dry period, from 1986 to 1994, and found a 27.5-inch precipitation deficit over that period. While that was overall greater than the current drought, the per year rain deficit is much higher this time around, Swain pointed out.

    Added to that, “temperatures in CA during the current drought have been warmer than during any previous drought on record, which has greatly amplified the effect of the precipitation deficits,” and helped fuel the wildfires currently flaring up around the state, Swain said.

    Many are hoping the current El Niño will make a serious dent in the drought, as it looks to become a strong event, and those are associated with higher odds of increased winter rains over at least parts of the state.

    The study found that the whole El Niño-Southern Oscillation cycle only accounts for about 6 percent of the variation in yearly California precipitation. That cycle encompasses not just strong El Niños, but weak ones, as well as neutral and La Niña conditions, and when separated out “very strong events (like the El Niño currently underway) exert a far greater influence upon California climate than weak ones,” Swain said. So this year’s El Niño could play a major role in what precipitation California sees.

    What’s important this year, Swain said, is where the precipitation falls and how much of it falls as snow to build back up the snowpack that keeps water flowing into reservoirs come the warm, dry days of summer.

    See the full article here.

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  • richardmitnick 11:03 am on March 3, 2015 Permalink | Reply
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    From ABC News: “The Big Melt: Antarctica’s Retreating Ice May Re-Shape Earth” 

    ABC News bloc

    ABC News

    Feb 27, 2015,
    Luis Andres Henao
    Seth Borenstein

    1
    In this Jan. 22, 2015 photo, a zodiac carrying a team of international scientists heads to Chile’s station Bernardo O’Higgins, Antarctica. Water is eating away at the Antarctic ice, melting it where it hits the oceans. As the ice sheets slowly thaw, water pours into the sea, 130 billion tons of ice (118 billion metric tons) per year for the past decade, according to NASA satellite calculations. (AP Photo/Natacha Pisarenko)

    From the ground in this extreme northern part of Antarctica, spectacularly white and blinding ice seems to extend forever. What can’t be seen is the battle raging thousands of feet (hundreds of meters) below to re-shape Earth.

    Water is eating away at the Antarctic ice, melting it where it hits the oceans. As the ice sheets slowly thaw, water pours into the sea — 130 billion tons of ice (118 billion metric tons) per year for the past decade, according to NASA satellite calculations. That’s the weight of more than 356,000 Empire State Buildings, enough ice melt to fill more than 1.3 million Olympic swimming pools. And the melting is accelerating.

    In the worst case scenario, Antarctica’s melt could push sea levels up 10 feet (3 meters) worldwide in a century or two, recurving heavily populated coastlines.

    Parts of Antarctica are melting so rapidly it has become “ground zero of global climate change without a doubt,” said Harvard geophysicist Jerry Mitrovica.

    Here on the Antarctic peninsula, where the continent is warming the fastest because the land sticks out in the warmer ocean, 49 billion tons of ice (nearly 45 billion metric tons) are lost each year, according to NASA. The water warms from below, causing the ice to retreat on to land, and then the warmer air takes over. Temperatures rose 5.4 degrees Fahrenheit (3 degrees Celsius) in the last half century, much faster than Earth’s average, said Ricardo Jana, a glaciologist for the Chilean Antarctic Institute.

    As chinstrap penguins waddled behind him, Peter Convey of the British Antarctic Survey reflected on changes he could see on Robert Island, a small-scale example and perhaps early warning signal of what’s happening to the peninsula and rest of the continent as a whole.

    “I was last here 10 years ago,” Convey said during a rare sunny day on the island, with temperatures just above freezing. “And if you compare what I saw back then to now, the basic difference due to warming is that the permanent patches of snow and ice are smaller. They’re still there behind me, but they’re smaller than they were.”

    Robert Island hits all the senses: the stomach-turning smell of penguin poop; soft moss that invites the rare visitor to lie down, as if on a water bed; brown mud, akin to stepping in gooey chocolate. Patches of the moss, which alternates from fluorescent green to rust red, have grown large enough to be football fields. Though 97 percent of the Antarctic Peninsula is still covered with ice, entire valleys are now free of it, ice is thinner elsewhere and glaciers have retreated, Convey said.

    Dressed in a big red parka and sky blue hat, plant biologist Angelica Casanova has to take her gloves off to collect samples, leaving her hands bluish purple from the cold. Casanova says she can’t help but notice the changes since she began coming to the island in 1995. Increasingly, plants are taking root in the earth and stone deposited by retreating glaciers, she says.

    “It’s interesting because the vegetation in some way responds positively. It grows more,” she said, a few steps from a sleeping Weddell seal. “What is regrettable is that all the scientific information that we’re seeing says there’s been a lot of glacier retreat and that worries us.”

    Just last month, scientists noticed in satellite images that a giant crack in an ice shelf on the peninsula called Larsen C had grown by about 12 miles (20 kilometers) in 2014. Ominously, the split broke through a type of ice band that usually stops such cracks. If it keeps going, it could cause the breaking off of a giant iceberg somewhere between the size of Rhode Island and Delaware, about 1,700 to 2,500 square miles (4,600 to 6,400 square kilometers), said British Antarctic Survey scientist Paul Holland. And there’s a small chance it could cause the entire Scotland-sized Larsen C ice shelf to collapse like its sister shelf, Larsen B, did in a dramatic way in 2002.

    A few years back, scientists figured Antarctica as a whole was in balance, neither gaining nor losing ice. Experts worried more about Greenland; it was easier to get to and more noticeable, but once they got a better look at the bottom of the world, the focus of their fears shifted. Now scientists in two different studies use the words “irreversible” and “unstoppable” to talk about the melting in West Antarctica. Ice is gaining in East Antarctica, where the air and water are cooler, but not nearly as much as it is melting to the west.

    “Before Antarctica was much of a wild card,” said University of Washington ice scientist Ian Joughin. “Now I would say it’s less of a wild card and more scary than we thought before.”

    Over at NASA, ice scientist Eric Rignot said the melting “is going way faster than anyone had thought. It’s kind of a red flag.”

    What’s happening is simple physics. Warm water eats away at the ice from underneath. Then more ice is exposed to the water, and it too melts. Finally, the ice above the water collapses into the water and melts.

    Climate change has shifted the wind pattern around the continent, pushing warmer water farther north against and below the western ice sheet and the peninsula. The warm, more northerly water replaces the cooler water that had been there. It’s only a couple degrees Fahrenheit warmer than the water that used to be there, but that makes a huge difference in melting, scientists said.

    The world’s fate hangs on the question of how fast the ice melts.

    At its current rate, the rise of the world’s oceans from Antarctica’s ice melt would be barely noticeable, about one-third of a millimeter a year. The oceans are that vast.

    But if all the West Antarctic ice sheet that’s connected to water melts unstoppably, as several experts predict, there will not be time to prepare. Scientists estimate it will take anywhere from 200 to 1,000 years to melt enough ice to raise seas by 10 feet, maybe only 100 years in a worst case scenario. If that plays out, developed coastal cities such as New York and Guangzhou could face up to $1 trillion a year in flood damage within a few decades and countless other population centers will be vulnerable.

    “Changing the climate of the Earth or thinning glaciers is fine as long as you don’t do it too fast. And right now we are doing it as fast as we can. It’s not good,” said Rignot, of NASA. “We have to stop it; or we have to slow it down as best as we can. ”

    See the full article here.

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  • richardmitnick 4:04 am on February 24, 2015 Permalink | Reply
    Tags: , Climate Change, ,   

    From Huff Post: “Here’s What Will Happen To New York City If The World’s Ice Sheets Melt” 

    Huffington Post
    The Huffington Post

    02/23/2015
    Christopher Mathias

    1

    A disconcerting report released last week revealed that New York City could see a 6-foot rise in sea levels by the end of this century. It would make nearly half a million New Yorkers vulnerable to flooding, and waterfront properties would be virtually uninhabitable.

    But what if climate change continues unabated for even longer? What will New York City look like if, say, both the Antarctic and Greenland ice sheets melt completely, raising sea levels an estimated 260 feet?

    Urban planner and cartographer Jeffrey Linn used computerized mapping to make a GIF demonstrating just that. Watch the city’s five boroughs disappear, with only the lofty heights of New Jersey’s Pallisades left as an island:

    2

    Linn, who posted the GIF on his blog Spatialities, told The Huffington Post he wanted to show people what the city would look like after “the terminal point for ice caps melting,” which some scientists estimate could happen in 1,000 to 10,000 years.

    “What would the world around me look like, where I live, if in thousands of years, this is supposed to happen?” Linn said he wondered.

    Linn also made this mesmerizing map of New York City after only 100 feet of sea level rise. The city’s neighborhoods and parks are cleverly rechristened with more nautical nomenclatures: Central Park is Central Shark, Bushwick is Flushwick, the West Village is Wet Village, and so on:

    3

    He’s made similarly alarming maps for his hometown of Seattle, as well as London and Montreal, among other cities.

    The polar ice caps are melting at an alarming rate, as manmade greenhouse gas emissions continue to trap the sun’s heat. Here, for example, is a 2012 video showing a lower Manhattan-sized piece of ice breaking off from the Greenland ice sheet:

    See the full article here.

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  • richardmitnick 4:15 am on February 18, 2015 Permalink | Reply
    Tags: , Climate Change,   

    From Rutgers: “Climate Change Driving Brutal Winter?” 

    Rutgers University
    Rutgers University

    February 18, 2015
    Kirk Moore

    1

    Prolonged cold snaps on the East Coast, California drought and frozen mornings in the South all have something in common – the atmospheric jet stream which transports weather systems that’s taken to meandering all over North America.

    Rutgers University climate scientist Jennifer Francis and colleagues link that wavy jet stream to a warming Arctic, where climate changes near the top of the world are happening faster than in Earth’s middle latitudes.

    A new study from Francis and University of Wisconsin-Madison scientist Stephen Vavrus, published in IOPscience, backs up that theory, with evidence linking regional and seasonal conditions in the Arctic to deeper north-south jet stream waves which will lead to more extreme weather across the country.

    “The real story is how persistent the pattern has been. It’s been this way nearly continually since December 2013…Warm in the west, cold in the east,” Francis said. “We think with the warming Arctic these types of very wavy patterns, although probably not in the same locations, will happen more often in the future.”

    This research has been controversial since the Hurricane Sandy disaster, when the wavy jet stream steered the storm on its sharp left turn and smack into the Jersey Shore. Francis and other researchers say the jet stream’s configuration was a key ingredient in the monster storm.

    Very wavy jet-stream patterns have been occurring more often since the 1990s, Francis says, and are now affecting weather around the northern hemisphere. This mid-February cold snap, for example, that has left millions of people waking up to below-zero and single-digit temperatures, might not be as deep as some southward dips, called troughs, in the jet stream. But the overall pattern has been around for weeks, and is also responsible for Boston’s record snowfall this winter and the worsening drought in western states.

    In contrast, an opposite pattern in winter 2012 led to more than 3,000 high winter temperature records being broken in the eastern U.S., Francis notes.

    “California is still dealing with this record-breaking drought, and Alaska is having one of its warmest winters on record,” Francis said.

    In Florida, orange growers have not had to deal with freezing temperatures for the past two years. But they are looking at their smallest harvest on record because of citrus disease and watching the southward cold outbreaks closely. “We’ve been fortunate that those jet streams have not reached into our citrus production areas,” said Andrew Meadows, a spokesman for Florida Citrus Mutual, the industry’s biggest trade group.

    On the West Coast, the Pacific Ocean water temperatures off California are much warmer than normal, holding at uncanny 64- to 65-degree levels this winter, according to Mike Conroy of West Coast Fisheries Consultants, who works with commercial fishermen still catching bluefin tuna on the Cortes Bank 100 miles off San Diego.

    2
    Rutgers University climate scientist Jennifer Francis

    Francis says these conditions make sense because water temperature trends in the eastern Pacific have reversed from the past decade and could be contributing to California’s warmer and drier weather as the jet stream takes an unusually large swing to the north.

    The phenomenon called Arctic amplification – defined as the enhanced sensitivity of the Arctic region to warming compared to lower latitudes – is changing large-scale upper level flows in the atmosphere, the paper suggests. Looking back at records dating to the late 1940s, it is evident that Arctic amplification of global warming is now continuing through all four seasons of the year, according to Francis and Vavrus.

    One challenge addressed by the new study is measuring the extent and strength of those jet stream waves, Vavrus said.

    While using a traditional measure of surface air temperature changes between Arctic regions and lower latitudes, Francis and Vavrus also present an alternative measure of the thickness of temperature layers higher in the atmosphere.

    Even scientists who are skeptical of the findings say it’s a good effort to resolve the problem of differentiating real changes in the jet stream’s behavior from random noise. This is an issue inherent in climate research – teasing out real long-term climate change from mere year-to-year variability of weather.

    Francis and Vavrus acknowledge criticism that their work is looking at relatively recent years since Arctic amplification emerged as a clear signal. Still, the researchers say there is no mistaking the trend since the 1990s: the Arctic probably hasn’t been this warm since the last major inter-glacial period 125,000 years ago.

    Back then, Francis said, the Earth was several degrees warmer than now and sea levels were several meters higher. “The recent changes we’ve seen are clearly linked to increasing greenhouse gases, and there’s no sign of abatement in our use of fossil fuels. This does not bode well for impacts of extreme weather and the ecosystem as a whole,” she said.

    “The biggest challenge in our research,” Francis said. “Is that rapid Arctic warming started very recently, so detecting a clear atmospheric response and linking it to a particular cause may take another decade. In the meantime, Mother Nature seems to be acting out.”

    See the full article here.

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    Rutgers, The State University of New Jersey, is a leading national research university and the state’s preeminent, comprehensive public institution of higher education. Rutgers is dedicated to teaching that meets the highest standards of excellence; to conducting research that breaks new ground; and to providing services, solutions, and clinical care that help individuals and the local, national, and global communities where they live.

    Founded in 1766, Rutgers teaches across the full educational spectrum: preschool to precollege; undergraduate to graduate; postdoctoral fellowships to residencies; and continuing education for professional and personal advancement.

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  • richardmitnick 6:47 pm on February 9, 2015 Permalink | Reply
    Tags: , Climate Change, ,   

    From New Scientist: “Melting ice spells volcanic trouble” 

    NewScientist

    New Scientist

    05 February 2015
    Fred Pearce

    1
    Melting glaciers could lead to volcanic eruptions (Image: Image Broker/REX)

    Melting ice is causing the land to rise up in Iceland – and perhaps elsewhere. The result, judging by new findings on the floor of the Southern Ocean, could be a dramatic surge in volcanic eruptions.

    Last week, researchers at the University of Arizona in Tucson showed that a recent dramatic uplift of the Earth’s crust in parts of Iceland coincided with the rapid melting of nearby glaciers.

    Kathleen Compton’s team used data from GPS receivers that have been attached to rocks since 1995 to show that some parts of south-central Iceland, where five of the country’s largest glaciers are melting fast, have been rising by around 3.5 centimetres a year. Away from the glaciers, the rates of land rise were much lower.

    Their explanation is that the disappearance of the ice is relieving pressure on rocks beneath and allowing them to spring up.

    Rapid rebound

    It has long been known that the Earth’s crust falls and rises as ice caps grow and melt. But the speed of the rebound is surprising, says Compton.

    Richard Katz of the University of Oxford finds the discovery “very exciting”. “The measurements show that there is a response even at a very short time-scale of 30 years,” he says.

    The land uplift could be handy to protect some coastal areas from rising sea levels as the melting ice flows into the oceans. But there is a growing fear among geologists that climate-induced changes to water and ice levels could trigger more dangerous events, such as volcanic eruptions.

    The evidence is mostly from the past. For instance, during the last great melt 12,000 years ago, volcanic activity on Iceland was up to 50 times greater than the activity observed over the past century, says Bill McGuire, a volcanologist at University College London. Iceland has suffered three major volcanic eruptions in the past five years – although no one has shown a certain link with climate change.

    Seabed clue

    And today, fresh evidence of climatic cues for volcanic eruptions emerges from an analysis of thousands of kilometres of ridges on the floor of the Southern Ocean. The ridges were created by huge eruptions.

    Through detailed analysis of the topography of the seabed, John Crowley of the University of Oxford shows that the eruptions coincided with phases of orbital wobbles known as Milankovitch cycles, which trigger ice ages.

    He concludes that glaciations caused the increase in eruptions. By locking up much of the world’s water in ice sheets on land, they lowered sea levels and so reduced the ocean’s pressure on the seabed enough to allow magma to escape from the Earth’s mantle. “Our work reinforces the link between climate change and volcanism,” says Katz, a co-author of the Crowley paper.

    So it seems that glaciation can trigger submarine eruptions, while deglaciation may lead to magma outflows on land.

    “Both these studies reinforce the idea that the wholesale redistribution of water that accompanies major climate change elicits a significant response from the solid earth in the form of potentially hazardous phenomena such as earthquakes and volcanic eruptions,” says McGuire. “We saw this very dramatically at the end of the last ice age, and we are seeing it again today in Iceland and elsewhere.”

    See the full article here.

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  • richardmitnick 1:29 pm on December 24, 2014 Permalink | Reply
    Tags: , , Climate Change,   

    From AAAS: “China confirms its southern glaciers are disappearing” 

    AAAS

    AAAS

    22 December 2014
    Christina Larson

    Glaciers in China that are a critical source of water for drinking and irrigation in India are receding fast, according to a new comprehensive inventory. In the short term, retreating glaciers may release greater meltwater, “but it will be exhausted when glaciers disappear under a continuous warming,” says Liu Shiyin, who led the survey for the Cold and Arid Regions Environmental and Engineering Research Institute in Lanzhou.

    f
    Midui Glacier in Tibet (Jan Reurink/Wikimedia Commons (CC BY 2.0))

    In 2002, Chinese scientists released the first full inventory of the country’s glaciers, the largest glacial area outside of Antarctica and Greenland. The data came from topographical maps and aerial photographs of western China’s Tibet and Xinjiang regions taken from the 1950s through the 1980s. That record showed a total glacial area of 59,425 square kilometers. The Second Glacier Inventory of China, unveiled here last week, is derived from high-resolution satellite images taken between 2006 and 2010. The data set is freely available online.

    Liu and his colleagues calculated China’s total glacial area to be 51,840 square kilometers—13% less than in 2002. That figure is somewhat uncertain because the previous inventory used coarser resolution images that may have mistaken extensive snow cover for permanent ice, says Raymond Bradley, director of the Climate System Research Center at the University of Massachusetts, Amherst, who was not involved in the project.

    Methodological quibbles aside, the latest inventory flags a marked retreat of glaciers in the southern and eastern fringes of the Tibetan Plateau. “We found the fastest shrinking glaciers are those in the central upper reach of the Brahmaputra River, between the central north Himalaya [and] the source region of the tributary of the Indus River,” Liu says.

    Matthias Huss, a glaciologist at the University of Fribourg in Switzerland, applauds the openness in sharing data, which hasn’t always been the norm in China. “It is highly useful that the colleagues from China have made their data set available to the community. It will feed directly into global efforts to compile a worldwide glacier inventory and is a major improvement,” he says. “It will, for example, greatly support the effort of global glacier modeling to improve our understanding of glaciers’ response to climate change.”

    See the full article here.

    The American Association for the Advancement of Science is an international non-profit organization dedicated to advancing science for the benefit of all people.

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