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.
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.
“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.
My BOINC
“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.
Brown University researchers will play key roles in a statewide research consortium, established by a new $19 million grant from the National Science Foundation to monitor and ultimately predict environmental change in Narragansett Bay.
The Rhode Island Consortium for Coastal Ecology, Assessment, Innovation and Modeling, will bring together research teams from around the Ocean State to study the impacts of climate variability on coastal ecosystems, create innovative technologies for detecting those changes, and build computer models to predict and plan for changes in coastal ecology.
Geoff Bothun, a professor of chemical engineering at the University of Rhode Island, is the grant’s principal investigator. Jeffrey Morgan, a professor of medicine and engineering at Brown, will serve as one of the grant’s co-principal investigators.
“Narragansett Bay is an environmental treasure that plays a critical role in the economy of the Ocean State,” Morgan said. “It’s also a natural laboratory that can help us understand how human activities, climate change and other factors drive environmental change. This grant will help us to monitor the bay in unprecedented detail and give us the tools to predict environmental change in the future.”
Morgan’s work on the grant will pertain to the development of new types of sensors to detect key environmental indicators.
“We want to be able to make more observations, more often and with greater specificity,” Morgan said. “These sensors will be looking at physical attributes of the bay — things like temperature, salinity and nutrients — as well as markers of biological change like algal blooms and microorganism populations.”
Baylor Fox-Kemper, an associate professor in Brown’s Department of Earth, Environmental and Planetary Sciences, will lend his expertise to the computer modeling side of the project.
“There’s a wealth of historical data that captures how the bay has responded to changes in human activity and a changing climate through time,” Fox-Kemper said. “The idea is use that data to build a model of the bay that accurately recreates its past, which we can then use to make predictions.”
The ultimate aim, Fox-Kemper says, is a model that can predict local-scale events like bacteria counts that result in beach closings, as well as larger scale changes in sea level, tidal patterns, temperature and salinity. The researchers plan to create a data center that will provide access to the observations and model data for scientists as well as government agencies, policymakers and citizen scientists.
The leaders of the research expect it to have broad impact, especially in a state that relies so heavily on its coastal resources.
“Research translation and commercialization is also a big emphasis for this grant,” Bothun said. “We’ll be forming an academic-industry partnership to learn about the challenges facing the marine and defense industries, for instance, and share with them some of our discoveries and technologies. This will also be a way to connect students with potential employment opportunities.”
Morgan says he expects the impact to go well beyond the borders of the Ocean State.
“We think the collaborative approach we’re developing here in Rhode Island will be a model for the study of coastal resources elsewhere in the U.S. and around the world,” he said. “Equally important, the undergraduates and graduate students we will engage in cutting-edge research that will further strengthen Rhode Island’s pipeline of investigators and innovators.”
Funding for the project comes from the National Science Foundation’s Established Program to Stimulate Competitive Research (EPSCoR) program, which aims to strengthen states’ research competitiveness and fund workforce development initiatives.
In addition to the NSF funding, the state of Rhode Island, through Commerce Rhode Island, has committed an additional $3.8 million toward the initiative that will be used to provide collaborative grants and support workforce development.
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.
Scientists have now pinpointed the location of the hot zone where hot materials rose to feed the caldera during its last period of activity in the 1980s.
Scientists have found the first direct evidence of a so-called ‘hot zone’ feeding a supervolcano in southern Italy that experts say is nearing eruption conditions.
Campi Flegrei is a volcanic caldera to the west of Naples that last erupted centuries ago.
The area has been relatively quiet since the 1980s when the injection of either magma or fluids in the shallower structure of the volcano caused a series of small earthquakes.
Using seismological techniques, scientists have now pinpointed the location of the hot zone where hot materials rose to feed the caldera during this period.
The study was led by Dr Luca De Siena at the University of Aberdeen in conjunction with the INGV Osservatorio Vesuviano, the RISSC lab of the University of Naples, and the University of Texas at Austin. The research provides a benchmark that may help predict how and where future eruptions could strike.
“One question that has puzzled scientists is where magma is located beneath the caldera, and our study provides the first evidence of a hot zone under the city of Pozzuoli that extends into the sea at a depth of 4 km,” Dr De Siena said.
“While this is the most probable location of a small batch of magma, it could also be the heated fluid-filled top of a wider magma chamber, located even deeper.”
Dr De Siena’s study suggests that magma was prevented from rising to the surface in the 1980s by the presence of a 1-2 km-deep rock formation that blocked its path, forcing it to release stress along a lateral route.
While the implications of this are still not fully understood, the relatively low amount of seismic activity in the area since the 1980s suggests that pressure is building within the caldera, making it more dangerous.
“During the last 30 years the behaviour of the volcano has changed, with everything becoming hotter due to fluids permeating the entire caldera,” Dr De Siena explained.
“Whatever produced the activity under Pozzuoli in the 1980s has migrated somewhere else, so the danger doesn’t just lie in the same spot, it could now be much nearer to Naples which is more densely populated.
“This means that the risk from the caldera is no longer just in the centre, but has migrated. Indeed, you can now characterise Campi Flegrei as being like a boiling pot of soup beneath the surface.
“What this means in terms of the scale of any future eruption we cannot say, but there is no doubt that the volcano is becoming more dangerous.
“The big question we have to answer now is if it is a big layer of magma that is rising to the surface, or something less worrying which could find its way to the surface out at sea.”
Founded in 1495 by William Elphinstone, Bishop of Aberdeen and Chancellor of Scotland, the University of Aberdeen is Scotland’s third oldest and the UK’s fifth oldest university.
William Elphinstone established King’s College to train doctors, teachers and clergy for the communities of northern Scotland, and lawyers and administrators to serve the Scottish Crown. Much of the King’s College still remains today, as do the traditions which the Bishop began.
King’s College opened with 36 staff and students, and embraced all the known branches of learning: arts, theology, canon and civil law. In 1497 it was first in the English-speaking world to create a chair of medicine. Elphinstone’s college looked outward to Europe and beyond, taking the great European universities of Paris and Bologna as its model.
Uniting the Rivals
In 1593, a second, Post-Reformation University, was founded in the heart of the New Town of Aberdeen by George Keith, fourth Earl Marischal. King’s College and Marischal College were united to form the modern University of Aberdeen in 1860. At first, arts and divinity were taught at King’s and law and medicine at Marischal. A separate science faculty – also at Marischal – was established in 1892. All faculties were opened to women in 1892, and in 1894 the first 20 matriculated female students began their studies. Four women graduated in arts in 1898, and by the following year, women made up a quarter of the faculty.
Into our Sixth Century
Throughout the 20th century Aberdeen has consistently increased student recruitment, which now stands at 14,000. In recent years picturesque and historic Old Aberdeen, home of Bishop Elphinstone’s original foundation, has again become the main campus site.
The University has also invested heavily in medical research, where time and again University staff have demonstrated their skills as world leaders in their field. The Institute of Medical Sciences, completed in 2002, was designed to provide state-of-the-art facilities for medical researchers and their students. This was followed in 2007 by the Health Sciences Building. The Foresterhill campus is now one of Europe’s major biomedical research centres. The Suttie Centre for Teaching and Learning in Healthcare, a £20m healthcare training facility, opened in 2009.
September 14, 2017
Alan Buis
Jet Propulsion Laboratory, Pasadena, California
818-354-0474 Alan.buis@jpl.nasa.gov
NASA Grace – Gravity Recovery and Climate Experiment
Gravity Recovery and Climate Experiment Mission Status Report
With one of its twin satellites almost out of fuel after more than 15 years of chasing each other around our planet to measure Earth’s ever-changing gravity field, the operations team for the U.S./German Gravity Recovery and Climate Experiment (GRACE) mission is making plans for an anticipated final science collection.
On Sept. 3, one of 20 battery cells aboard the GRACE-2 satellite stopped operating due to an age-related issue. It was the eighth battery cell loss on GRACE-2 since the twin satellites that compose the GRACE mission launched in March 2002 on a mission designed to last five years. The following day, contact was lost with GRACE-2.
On Sept. 8, following numerous attempts, the GRACE mission operations team at NASA’s Jet Propulsion Laboratory in Pasadena, California; Deutsches Zentrum für Luft- und Raumfahrt (DLR, the German Aerospace Center) in Oberpfaffenhofen, Germany; and the Helmholtz Centre Potsdam German Research Centre for Geosciences (GFZ) in Potsdam, Germany, uplinked commands to GRACE-2 to bypass the satellite’s flight software system. The procedure restored communications with the spacecraft, allowing the team to regain control. Subsequent analyses revealed that the battery cell lost on Sept. 3 had recovered its full voltage, and that GRACE-2 had essentially hibernated during the period of lost contact, consuming no fuel. Following an assessment of the satellite’s overall health, the team has determined that GRACE’s dual satellite science mission can continue.
The team has uplinked commands to GRACE-2 to place it in a passive state that will allow it to maintain its current level of fuel. Operational procedures have begun that will extend the GRACE mission to its next science operations phase, which runs from mid-October to early November. During that time, GRACE-2 will be in full Sun, so it will not need to use its batteries.
The team expects the October/November science data collection to be the mission’s last before GRACE-2 runs out of fuel. The additional monthly gravity map produced will help further extend GRACE’s data record closer to the launch of GRACE’s successor mission, GRACE-Follow-On, scheduled for early 2018.
As directed by the mission’s Joint Steering Group, final decommissioning for both GRACE-1 and GRACE-2 will begin once the dual satellite science phase concludes.
GRACE tracks the movement of water around our planet caused by Earth’s changing seasons, weather and climate processes, and human activities. The mission has mapped Earth’s ever-changing gravity field in unprecedented detail, showing how water, ice and solid Earth material move on or near Earth’s surface. GRACE operates by sensing minute changes in gravitational pull caused by local changes in Earth’s mass. To observe these changes, GRACE uses a microwave ranging system that measures micron-scale variations in the 137-mile (220-kilometer) distance between the spacecraft, along with GPS tracking, star trackers for attitude information and an accelerometer to account for non-gravitational effects such as atmospheric drag. From these data collected over Earth’s surface, scientists can infer Earth’s gravity field.
GRACE’s monthly maps of regional variations in gravity have given scientists new insights into Earth system processes. Among its many innovations, GRACE has been used to monitor the loss of ice from Earth’s ice sheets, improve understanding of the processes responsible for sea level rise and ocean circulation, provide insights into where aquifers may be shrinking or where dry soils are contributing to drought, and monitor changes in the solid Earth.
GRACE is a joint NASA/DLR mission led by the principal investigator at the University of Texas at Austin and co-principal investigator at GFZ. GRACE ground segment operations are co-funded by GFZ, DLR and the European Space Agency. JPL manages GRACE for NASA’s Science Mission Directorate in Washington.
Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.
Six months after the Antarctic Circumnavigation Expedition ended, the teams that ran the 22 scientific projects are hard at work sorting through the many samples they collected. Some preliminary findings were announced during a conference in Crans Montana organized by the Swiss Polar Institute, who just appointed Konrad Steffen as new scientific director (see the interview below).
Nearly 30,000 samples were taken during the Antarctic Circumnavigation Expedition (ACE). And now, barely six months after the voyage ended, the research teams tasked with analyzing the samples have already produced some initial figures and findings. These were presented in Crans Montana during a conference put together earlier this week by the Swiss Polar Institute (SPI), the EPFL-based entity that ran the expedition. The event, called “High altitudes meet high latitudes,” brought together world-renowned experts in polar and alpine research in an exercise aimed at highlighting the many similarities between these two fields of study.
Over the course of three months – from December 2016 to March 2017 – 160 researchers from 23 different countries sailed around the Great White Continent on board a Russian icebreaker. They ran 22 research projects in an effort to learn more about the impact of climate change on these fragile and little-known regions. The valuable samples, taken from the Southern Ocean, the atmosphere and a handful of remote islands, are now back at the labs of the 73 scientific institutions involved in the expedition.
The route of the ACE expedition.
Most of the teams that ran the 22 projects are still carrying out the preliminary task of sorting through and identifying the samples, which means the initial results are necessarily incomplete and provisional. It is only later that the samples will be analyzed. Some important observations can nevertheless be made at this stage.
A solid database
The sum total of the samples collected represents an impressive and valuable database. The SPI must now come up with ways to organize, group and present the data so that researchers can readily access and make use of it. What’s more, “the large number of potential collaborations and exchanges between projects is becoming clear,” says David Walton, the chief scientist on the expedition. “Some research projects have been found to have links with as much as nine others.” And some startling figures have already been released – here is a look at just a few of them.
For the SubIce project, around 100 meters of ice cores were taken on five subantarctic islands and the Mertz Glacier, which sits on the edge of the Antarctic continent. The chemical composition of the cores will be analyzed in an attempt to trace climate change over recent decades. In some places, like Balleny, Peter 1st or Bouvet Islands, it was the first time an ice sample had ever been taken. “Of all the islands where we were able to take samples, that last one was the farthest from the continent,” says Liz Thomas, from British Antarctic Survey. “It’s also the island where the ice in the samples is the most granular. Our findings confirm significant seasonal variations at this location.”
The air on the continent is so pure that even the hottest cup of tea does not produce any steam. “No particles, no clouds,” explains Julia Schmale, a researcher with the Paul-Scherrer-Institute who measured for aerosols – tiny chemical particles like grains of sand, dust, pollen, soot, sulfuric acid, and so on – throughout the expedition. These particles attach to water molecules and aggregate to form clouds. On Mertz Glacier, her measurements revealed aerosol levels below 100 particles per cm3, which is less than the level found in a cleanroom.
Christel Hassler and her team, from the University of Geneva, studied bacteria and virus populations in the Southern Ocean. The team took some 170 samples from all around the continent. For the time being, their work consists in isolating and culturing the numerous cells found in the samples. “We will then analyze their DNA in order to identify them,” says Marion Fourquez, a marine biologist. “That will show us whether we have come across any new bacterial strains that have yet never been observed in this region.”
One of the subsequent lines of research will be to determine their geographical distribution. The researchers will be able to tell if there’s a link between the presence of a given bacterium and that of other microorganisms by comparing their data with data from other projects, like Nicolas Cassar’s. Cassar, from Duke University in the United States, measured concentrations of phytoplankton, which sit at the very bottom of the region’s food chain. “This approach worked out well, and we have nearly continuous samples from along the entire route,” says Walton.
More than 3,000 whales
Brian Miller, from the Australian Antarctic Division, was interested in somewhat larger animals. For his project, he used a piece of sophisticated acoustic equipment to listen for and count the number of whales in the Southern Ocean. Walton notes: “In around 500 hours of recordings, the researchers counted for example over 3,000 individual blue whales, although we actually saw only three or so at the surface.” These cetaceans appear to be particularly plentiful in the depths of the Ross Sea.
Peter Ryan, from the University of Cape Town in South Africa, observed and counted bird populations. He discovered that one of the largest colonies of king penguins, on Pig Island in the Crozet archipelago, had declined drastically – he estimates the numerical loss to be around 75%. “That’s around half a million animals,” says Walton. “We don’t know if they’ve died or migrated to other colonies, like the one in St. Andrews Bay, in South Georgia, which is actually in a growth phase.”
More complete and detailed results will be published in the coming months.
Konrad Steffen, a glaciologist and the new scientific director of the Swiss Polar Institute (SPI), has been involved in polar research for the past 40 years. His work has focused primarily on the Arctic, particularly the changes taking place within Greenland’s ice sheet. He is also a professor at ETH Zurich and director of the Swiss Federal Institute for Forest, Snow and Landscape Research WSL.
Professor Steffen, why is the Swiss Polar Institute so necessary today?
Research in this field tended to be conducted by small groups that organized their own expeditions and ran their own projects. In Switzerland, there had never been any kind of initiative aimed at coordinating all this work. The effects of climate change on polar and alpine regions are now so evident that we urgently need to coordinate our efforts and conduct cross-disciplinary research. This is what we did with the ACE project, where researchers from fields like oceanography, glaciology and biology came together in an attempt to improve our understanding of the climate-change process in a region.
What for you is the top priority when it comes to the polar regions?
At the SPI, one of our aims is to devise a strategic plan within the scientific community. More personally, I think that we urgently need to assess the mass balance of ice sheets across the globe. That’s what will have the greatest and swiftest impact in terms of rising sea levels and changes to our coastlines. Instead of studying individual glaciers in the Alps, we need to look at the bigger picture and observe in detail how the atmosphere interacts with large ice sheets, such as those in Greenland and the Antarctic. We need to connect the dots to see how the system as a whole is affected.
What made the ACE such an innovative expedition?
There have been many scientific expeditions to the Antarctic, but they usually only cover part of the continent. This was the first time that an expedition went all the way around the continent in one three-month period, studying all the oceans during the same season. That provides a fuller picture of the issues, such as microplastics – during the trip, we really saw that they were everywhere! The expedition also served up attractive career opportunities for budding young scientists and enabled several research groups to establish long-term partnerships.
Are any other expeditions in the pipeline?
Yes, the next one is planned for 2019. The aim is to sail around Greenland. We are in the process of looking for a vessel and determining what sort of research will be undertaken during the trip.
EPFL is Europe’s most cosmopolitan technical university with students, professors and staff from over 120 nations. A dynamic environment, open to Switzerland and the world, EPFL is centered on its three missions: teaching, research and technology transfer. EPFL works together with an extensive network of partners including other universities and institutes of technology, developing and emerging countries, secondary schools and colleges, industry and economy, political circles and the general public, to bring about real impact for society.
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.
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.
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.
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.
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.
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.
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.
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.
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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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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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.
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.
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.”
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.
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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.”
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.
Researchers probe natural environments near subduction zones to decrypt underlying mechanisms of major earthquakes.
FEMA
A diagram of the Cascadia Subduction Zone provided by the Oregon Historical Society.
The Cascadia subduction zone is likely to experience a megathrust earthquake in the next 50 years or so, but a revised technique uses heat data to better understand the physical nature of subduction zones. Credit: NASA/ISS
Along the west coast of North America, the Cascadia subduction zone stretches more than 1,000 kilometers from Vancouver Island to Cape Mendocino, Calif. It produced a magnitude 9 megathrust earthquake about 300 years ago, one of the biggest quakes in world history.
Scientists know that Cascadia will produce another earthquake at some point in the future; the question is how soon. The odds of it happening in the next 50 years are 1 in 3. The Federal Emergency Management Agency projects that Cascadia’s next megathrust earthquake will cause thousands of deaths and injuries and leave millions in need of shelter, food, and water.
To better understand subduction zones, scientists often study the thermal environments of material that has been pushed up onto the surface during past earthquakes. This buildup of material, called an accretionary wedge, might consist of rock, soil, sand, shells, or any other kind of debris. These wedges also sport subtly different average temperatures at various depths, compared to material located off the wedge.
In a recent study, Salmi et al. [Journal of Geophysical Research] examined the thermal environment of the Cascadia subduction zone’s accretionary wedge, which stretches for about 97 kilometers along the coast of the state of Washington. Their goal was to find out more about the physical changes of fluids and solids within the wedge in the hopes that the knowledge can help them better anticipate future earthquakes.
Using data collected on a cruise by the R/V Marcus G. Langseth, the researchers found significant variations in temperature within this section of the Cascadia subduction zone, as well as signs of gas hydrates (ice-like deposits that form from natural gas at the bottom of the ocean) throughout the region. They also detected that most fluids from the deep move upward through the accretionary wedge instead of through the crust, which is different than in most other subduction zones. This change in fluid pathway prevents the plate from cooling and reduces the area where an earthquake might rupture along the two plates: completely within the accretionary wedge, rather than under the continental plate.
This is the first study to concentrate on the southern Washington margin alone, rather than the subduction zone as a whole, revealing the influence of fluid distribution on local, small-scale temperature variability. This insight opens the door to further research into how local temperature variability might interact with other factors, like stress or fault roughness, to affect earthquake hazards. Overall, this study provides a revised method for probing the thermal environment of an accretionary wedge, a crucial link to the cause of ruptures in Earth’s crust that can lead to earthquakes and tsunamis.
By understanding these mechanisms more fully, scientists can tell us more about how to prepare for the smallest of tremors and the largest of megaquakes. (Journal of Geophysical Research: Solid Earth, https://doi.org/10.1002/2016JB013839, 2017)
Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.
These microscopic zircons collected from Mount Narryer in Western Australia have been dated at more than 4.1 billion years old. Auscape / Getty
Zirconium is the eighteenth most common element in the Earth’s crust – more common than such well-known substances as zinc, copper, nickel, and chromium. But most people have never heard of it, unless in the form of imitation diamonds known as cubic zirconia.
In nature, zirconium forms another type of crystal called zircons. To geophysicists, these are the true gems, because they provide vital time capsules from the Earth’s deepest past.
Chemically, zircons are nothing fancy. They are tiny lumps of zirconium silicate (ZrSiO4) that are ubiquitous in volcanic rocks. But they’re typically only 0.1 mm to 0.3 mm across, making them hard to spot without a magnifying glass. Not exactly the type of thing most of us would notice, let alone care about.
But they have two important traits.
One is that they are incredibly durable. The rocks in which they initially formed may weather away, but the zircons survive as tiny grains of sand that may later be incorporated into the next generation of rocks.
“We have no rocks that are older than 4 billion years,” says John Valley, a geochemist at the University of Wisconsin, Madison. (The Earth itself is 4.543 billion years old.) “[Zircons] are what we study if we want to analyze things that formed that far back.”
Their other trait is that they aren’t pure zirconium silicate. They contain trace amounts of other elements, most importantly uranium, trapped within them as they crystalize. Over the eons, that uranium slowly decays to lead. By comparing the amounts of uranium and lead, scientists can determine the date at which the crystal formed.
Another element, oxygen (the “O” in ZrSiO4), helps tell the conditions under which each zircon formed. That’s because oxygen has two well-known stable isotopes, 16O and 18O, either of which can be incorporated into the crystal as it grows.
Typically, these come from water (H2O), which can contain either 16O or 18O (or a more rare stable isotope called 17O). All these forms of water are chemically identical, but 18O-containing water is about ten percent heavier than 16O-containing water. That causes the two types of water to (very slightly) separate — and to do so by different amounts under different conditions.
Geologists once thought the early Earth was far too hot for its surface to be anything but an ocean of magma, let alone to have liquid water. In fact, the earliest period in the Earth’s history, from its formation to 4 billion years ago, is called the Hadean because it was widely believed to resemble hell, or Hades.That meant zircons from the Hadean period should have oxygen isotope ratios comparable to that of water molecules in the Earth’s mantle. But geologists studying the Jack Hills region of Western Australia, which has yielded the oldest zircons ever found, have been unearthing zircons from as far back as 4.375 billion years ago whose oxygen isotope ratios show they may have formed from magma that incorporated liquid water.
Other zircon research has suggested that life too may date back a lot further than we once thought. This research involves the ratio of non-radioactive carbon isotopes (12C and 13C) in tiny diamonds incorporated in the zircon structure. These diamonds have carbon isotope signatures suggesting the carbon from which they were formed may have included organic material from living organisms.
“This implies that there was life in the Hadean,” says Craig O’Neill, a geodynamicist at Macquarie University. Though, he notes, there are other explanations involving purely geologic processes. “It’s hard to be sure,” he says.
Still more studies have used hyper-sensitive magnets to look for trace magnetic fields carried by magnetic impurities in ancient zircons, in the hope of determining the strength of the Earth’s magnetic field at the time these zircons formed. “The analysis takes about a week,” says John Tarduno, a geophysicist at the University of Rochester, New York. Such studies, he says, indicate that the Earth’s magnetic field might be as old as its zircons.
And that’s just the beginning. In a 2017 study in Science Advances, geophysicists used zircons in Moon rocks brought back by Apollo astronauts to determine that the Moon’s crust solidified 4.51 billion years ago, only 60 million years after the formation of the first protoplanets. And zircons in meteorites blasted off the surface of Mars are being studied to peer nearly as far back into the Red Planet’s early history.
So who cares if copper, zinc, nickel, and chromium are vastly more valuable to the modern economy? Lowly zirconium may be what helps us unravel the greatest of all mysteries: who we are and where we came from.
Colorado forest study provides clearest-ever picture of gases released into the atmosphere and how they change.
“The goal was trying to understand the chemistry associated with organic particulate matter in a forested environment,” associate professor Jesse Kroll explains. “We took a lot of measurements using state-of-the-art instruments we had developed.” The team also took many photos while in Colorado. Pictured on the bottom right is Douglas Day, CU researcher and organizer of the field campaign. Courtesy of the researchers.
For a few weeks over the summer in 2011, teams of scientists from around the world converged on a small patch of ponderosa pine forest in Colorado to carry out one of the most detailed, extended survey of atmospheric chemistry ever attempted in one place, in many cases using new measurement devices created especially for this project. Now, after years of analysis, their comprehensive synthesis of the findings have been released this week.
The teams, which included a group from MIT using a newly-developed device to identify and quantify compounds of carbon, reported their combined results in a paper in the journal Nature Geoscience. Jesse Kroll, MIT associate professor of civil and environmental engineering and of chemical engineering, and James Hunter, an MIT technical instructor in the Department of Materials Science and Engineering who was a doctoral student in Kroll’s group at the time of the research, were senior author and lead author, respectively, of the 24 contributors to the report. Associate Professor Colette Heald of the Department of Civil and Environmental Engineering was also a co-author.
The organic (carbon-containing) compounds they studied in that patch of Colorado forest play a key role in atmospheric chemical processes that can affect air quality, the health of the ecosystem, and the climate itself. Yet many of these processes remain poorly understood in their real-world complexity, and they had never been so rigorously sampled, studied, and quantified in one place before.
“The goal was trying to understand the chemistry associated with organic particulate matter in a forested environment,” Kroll explains. “The various groups took a lot of different measurements using state-of-the-art instruments we each had developed.” In doing so, they were able to fill in significant gaps in the inventory of organic compounds in the atmosphere, finding that about a third of them were in the form of previously unmeasured semi-volatile and intermediate-volatility organic compounds (SVOCs and IVOCs).
“We’ve long suspected there were gaps in our measurements of carbon in the atmosphere,” Kroll says. “There seemed to be more aerosols than we can explain by measuring their precursors.”
The MIT team, as well as some of the other research groups, developed instruments that specifically targeted these hard-to-measure compounds, which Kroll describes as “still in the gas phase, but sticky.” Their stickiness makes it hard to get them through an inlet into a measuring device, but these compounds may play a significant role in the formation and alteration of aerosols, tiny airborne particles that can contribute to smog or to the nucleation of raindrops or ice crystals, affecting the Earth’s climate.
“Some of these instruments were used for the first time in this campaign,” Kroll says. When analyzing the results, which provided unprecedented measurements of the SVOCs and IVOCs, “we realized we had this data set that provided much more information on organic compounds than we ever had before. By bringing the data from all these instruments together into one combined dataset, we were able to describe the organic compounds in the atmosphere in a more comprehensive way than had ever been possible, to figure out what’s really going on.”
It’s a more complicated challenge than it might seem, the researchers point out. A very large number of different organic compounds are constantly being emitted by trees and other vegetation, which vary in their chemical composition, their physical properties, and their ability to react chemically with other compounds. As soon as they enter the air many of the compounds begin to oxidize, which exponentially increases their number and diversity.
The collaborative campaign to characterize the quantities and reactions of these different compounds took place in a section of the Manitou Experimental Forest Observatory in the Rocky Mountains of Colorado. Five different instruments were used to collect the data on organic compounds, and three of those had never been used before.
Despite the progress, much remains to be done, the researchers say. While the field measurements provided a detailed profile of the amounts of different compounds over time, it could not identify the specific reactions and pathways that were transforming one set of compounds to another. That kind of analysis requires the direct study of the reactions in a controlled laboratory setting, and that kind of work is ongoing, in Kroll’s MIT lab and elsewhere.
Filling in all these details will make it possible to refine the accuracy of atmospheric models and help to assess such things as strategies to mitigate specific air pollution issues, from ozone to particulate matter, or to assess the sources and removal mechanisms of atmospheric components that affect Earth’s climate.
The measurement team included researchers from the University of Colorado, the California Air Resources Board, the University of California at Berkeley, the University of Toronto, the University of Innsbruck in Austria, the National Center for Atmospheric Research, the Edmund Mach Foundation in Italy, Harvard University, the University of Montreal, Aerodyne Research, Carnegie-Mellon University, the University of California at Irvine, and the University of Washington. The work was funded by the National Oceanic and Atmospheric Administration.
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