Climate News

January 27, 2011

The temperatures of North Atlantic Ocean water flowing north into the Arctic Ocean adjacent to Greenland -- the warmest water in at least 2,000 years -- are likely related to the amplification of global warming in the Arctic, says a new international study involving the University of Colorado Boulder.

Led by Robert Spielhagen of the Academy of Sciences, Humanities and Literature in Mainz, Germany, the study showed that water from the Fram Strait that runs between Greenland and Svalbard -- an archipelago constituting the northernmost part of Norway -- has warmed roughly 3.5 degrees Fahrenheit in the past century. The Fram Strait water temperatures today are about 2.5 degrees F warmer than during the Medieval Warm Period, which heated the North Atlantic from roughly 900 to 1300 and affected the climate in Northern Europe and northern North America.

The team believes that the rapid warming of the Arctic and recent decrease in Arctic sea ice extent are tied to the enhanced heat transfer from the North Atlantic Ocean, said Spielhagen. According to CU-Boulder's National Snow and Ice Data Center, the total loss of Arctic sea ice extent from 1979 to 2009 was an area larger than the state of Alaska, and some scientists there believe the Arctic will become ice-free during the summers within the next several decades.

"Such a warming of the Atlantic water in the Fram Strait is significantly different from all climate variations in the last 2,000 years," said Spielhagen, also of the Leibniz Institute of Marine Sciences in Keil, Germany.

According to study co-author Thomas Marchitto, a fellow at CU-Boulder's Institute of Arctic and Alpine Research, the new observations are crucial for putting the current warming trend of the North Atlantic in the proper context.

"We know that the Arctic is the most sensitive region on the Earth when it comes to warming, but there has been some question about how unusual the current Arctic warming is compared to the natural variability of the last thousand years," said Marchitto, also an associate professor in CU-Boulder's geological sciences department. "We found that modern Fram Strait water temperatures are well outside the natural bounds."

A paper on the study will be published in the Jan. 28 issue of Science. The study was supported by the German Research Foundation; the Academy of Sciences, Humanities and Literature in Mainz, Germany; and the Norwegian Research Council.

Other study co-authors included Kirstin Werner and Evguenia Kandiano of the Leibniz Institute of Marine Sciences, Steffen Sorensen, Katarzyna Zamelczyk, Katrine Husum and Morten Hald from the University of Tromso in Norway and Gereon Budeus of the Alfred Wegener Institute of Polar and Marine Research in Bremerhaven, Germany.

Since continuous meteorological and oceanographic data for the Fram Strait reach back only 150 years, the team drilled ocean sediment cores dating back 2,000 years to determine past water temperatures. The researchers used microscopic, shelled protozoan organisms called foraminifera -- which prefer specific water temperatures at depths of roughly 150 to 650 feet -- as tiny thermometers.

In addition, the team used a second, independent method that involved analyzing the chemical composition of the foraminifera shells to reconstruct past water temperatures in the Fram Strait, said Marchitto.

The Fram Strait branch of the North Atlantic Current is the major carrier of oceanic heat to the Arctic Ocean. In the eastern part of the strait, relatively warm and salty water enters the Arctic. Fed by the Gulf Stream Current, the North Atlantic Current provides ice-free conditions adjacent to Svalbard even in winter, said Marchitto.

"Cold seawater is critical for the formation of sea ice, which helps to cool the planet by reflecting sunlight back to space," said Marchitto. "Sea ice also allows Arctic air temperatures to be very cold by forming an insulating blanket over the ocean. Warmer waters could lead to major sea ice loss and drastic changes for the Arctic."

The rate of Arctic sea ice decline appears to be accelerating due to positive feedbacks between the ice, the Arctic Ocean and the atmosphere, Marchitto said. As Arctic temperatures rise, summer ice cover declines, more solar heat is absorbed by the ocean and additional ice melts. Warmer water may delay freezing in the fall, leading to thinner ice cover in winter and spring, making the sea ice more vulnerable to melting during the next summer.

Air temperatures in Greenland have risen roughly 7 degrees F in the past several decades, thought to be due primarily to an increase in Earth's greenhouse gases, according to CU-Boulder scientists.

"We must assume that the accelerated decrease of the Arctic sea ice cover and the warming of the ocean and atmosphere of the Arctic measured in recent decades are in part related to an increased heat transfer from the Atlantic," said Spielhagen.

Contact

Robert Spielhagen, 011-49-431-600-2855
rspielhagen@ifm-geomar.de
Thomas Marchitto, 303-492-7739
Thomas.Marchitto@colorado.edu

The NSF-funded Climate Literacy & Energy Awareness Network (CLEAN) assembles a new peer-reviewed digital collection as part of the National Science Digital Library (NSDL) featuring teaching materials centered on climate and energy science for grades 6-16 and for citizens.

The CLEAN Pathway project uses the Essential Principles of Climate Science (CCEP 2009) and newly-developed Energy Awareness Principles to steward a broad collection of teaching materials that facilitate students, teachers, and citizens becoming climate literate and informed about climate and energy science and solutions.

The first part of the collection was launched in the fall of 2010. Each featured teaching material has undergone a rigorous review process and provides teaching tips by experts on how to implement the materials in the classroom. All materials are aligned with Benchmarks for Science Literacy. The alignment with the National Science Education Standards and the Excellence in Environmental Education Guidelines for Learning through interactive strandmaps will be completed by the fall of 2011.

Efforts to build a community of practitioners in climate education have started and will continue in the following years. In the spring of 2011 the CLEAN team will offer professional development opportunities related to the collection.

December 15, 2008

Rocky Mountain ski areas face dramatic changes this century as the climate warms, including best-case scenarios of shortened ski seasons and higher snowlines and worst-case scenarios of bare base areas and winter rains, says a new Colorado study.

The study indicates snowlines -- elevations below which seasonal snowpack will not develop -- will continue to rise through this century, moving up more than 2,400 feet from the base areas of Colorado's Aspen Mountain and Utah's Park City Mountain by 2100, said University of Colorado at Boulder geography Professor Mark Williams. Williams and Brian Lazar of Stratus Consulting Inc. of Boulder combined temperature and precipitation data for Aspen Mountain and Park City Mountain with general climate circulation models for the study.

The pair came up with three scenarios for each of the two ski havens for the years 2030, 2075 and 2100. The low-emissions scenario is based on the presumption that the world begins reducing CO2 emissions, said Williams. The "business-as-usual" scenario assumes the future rate of CO2 increase will be similar to the current rate, while the high-emissions scenario assumes future CO2 emissions will increase over the present rate.

Their forecasts indicate the "business as usual" scenario will cause average temperatures to rise by nearly 4 degrees Fahrenheit at Aspen and Park City by 2030 and 8.6 degrees F in Aspen and 10.4 degrees F for Park City by 2100, said Williams. A paper by Williams and Lazar was presented at the Fall Meeting of the American Geophysical Union held Dec. 15-19 in San Francisco.

"Ski industry officials know that warming is real, and that small changes in climate have substantial effects on ski areas," said Williams, also a fellow at CU-Boulder's Institute of Arctic and Alpine research. "The bad news is that the past five years of global CO2 emissions have exceeded our high-emissions scenario."

Under each of the emissions scenarios, the length of the ski seasons in Aspen and Park City by 2030 "will be squeezed on each shoulder," with delayed snowpack and earlier melting seasons, he said. Under the high-emissions scenario, Park City will have no snowpack at its base by 2100 and winter precipitation will come in the form of rain.

While the modeling by Williams and Lazar targeted Aspen Mountain and Park City, other ski areas in the Rockies and beyond are likely to be similarly or more drastically affected, said Williams. Many ski areas in California's Sierra Nevada, the Cascade Mountains in Oregon and Washington, and smaller ski areas in the mid-eastern portion of America like Pennsylvania and West Virginia, for example, could be forced out of business in the coming decades as air temperatures continue to warm, he said.

The key to the survival of the larger ski areas in the Rockies is adaptation, said Williams. Ski resorts must expand operations to higher elevations and more northerly parcels of land. They also must beef up gondola transportation systems to shuttle large loads of skiers efficiently from base areas with scant or no snow to snow-packed facilities located at higher elevations, he said.

At most Rocky Mountain ski areas, snowmaking will have to be stepped up considerably in the coming decades, said Williams. Increases in man-made snow will require the diversion and storage of large amounts of water, a challenging and expensive proposition since water rights are already over-appropriated throughout much of the West, he said.

Aspen Mountain, for example, may have to triple its snowmaking efforts in the coming decades because of warming temperatures, meaning an additional 50 cubic feet per second of water must be obtained per month, said Williams. But since appropriating significant amounts of winter water from streams adjacent to most ski areas would leave insufficient flows to maintain healthy aquatic ecosystems, resort operators are looking further and further afield for available water, he said.

"The bottom line is that in order to survive, these ski areas will need to find the necessary water wherever they can and hold it in storage to satisfy future snowmaking needs," Williams said. "Ski resort operators are really scrambling."

The new study was sponsored by Aspen Mountain and the Park City Mountain Resort said Lazar, who noted that two nonprofits -- the Aspen Global Change Institute and the Park City Foundation -- are working with the ski areas to better understand environmental climate change. "The results from studies like ours allow ski areas to try and better plan for the future, including how to be proactive on climate change in the community and region," said Lazar.

Williams and Lazar said many U.S. ski areas will likely follow the lead of ski areas in the European Alps by moving water from basin to basin over long distances and storing it at high elevations to satisfy future snowmaking needs. Ski areas could

generate their own hydropower by pumping water into and out of narrow, deep artificial lakes and small dams lined with plastic to minimize evaporation in the summers.

"It would be a win-win situation," Williams said. "The ski areas could recover some of their costs incurred from purchasing expensive water rights, providing some of their own hydropower to help run the resorts."

Snowmaking has been on the increase in the Alps for decades, where air temperatures have increased nearly 4 degrees F in the past 30 years, said Williams. In the Italian Alps, 70 percent of the skiable terrain is covered by artificial snow, and ski areas in the French Alps now make about 30 percent of their snow, he said.

Studies have shown that private jets that fly celebrities and vacationers in and out of Aspen for winter ski jaunts and summer recreation trips are by far the biggest CO2 emitters in the Roaring Fork Valley.

View the video here.

Contact

Mark Williams, 303-492-8830
markw@culter.colorado.edu
Brian Lazar, 303-381-8000
BLazar@stratusconsulting.com

January 14, 2011

Joint news release from the American Geophysical Union, CU-Boulder Laboratory for Atmospheric and Space Physics and Naval Research Laboratory

WASHINGTON—Scientists have taken a major step toward accurately determining the amount of energy that the sun provides to Earth, and how variations in that energy may contribute to climate change.

In a new study of laboratory and satellite data, researchers report a lower value of that energy, known as total solar irradiance, than previously measured and demonstrate that the satellite instrument that made the measurement—which has a new optical design and was calibrated in a new way—has significantly improved the accuracy and consistency of such measurements.

The new findings give confidence, the researchers say, that other, newer satellites expected to launch starting early this year will measure total solar irradiance with adequate repeatability – and with little enough uncertainty – to help resolve the long-standing question of how significant a contributor solar fluctuations are to the rising average global temperature of the planet.

"Improved accuracies and stabilities in the long-term total solar irradiance record mean improved estimates of the sun's influence on Earth's climate," said Greg Kopp of the Laboratory for Atmospheric and Space Physics (LASP) of the University of Colorado Boulder.

Kopp, who led the study, and Judith Lean of the Naval Research Laboratory, in Washington, D.C., published their findings today in Geophysical Research Letters, a journal of the American Geophysical Union.

The new work will help advance scientists' ability to understand the contribution of natural versus anthropogenic causes of climate change, the scientists said. That's because the research improves the accuracy of the continuous, 32-year record of total solar irradiance, or TSI. Energy from the sun is the primary energy input driving Earth's climate, which scientific consensus indicates has been warming since the Industrial Revolution.

Lean specializes in the effects of the sun on climate and space weather. She said, "Scientists estimating Earth's climate sensitivities need accurate and stable solar irradiance records to know exactly how much warming to attribute to changes in the sun's output, versus anthropogenic or other natural forcings."

The new, lower TSI value was measured by the LASP-built Total Irradiance Monitor (TIM) instrument on the NASA Solar Radiation and Climate Experiment (SORCE) spacecraft. Tests at a new calibration facility at LASP verify the lower TSI value. The ground-based calibration facility enables scientists to validate their instruments under on-orbit conditions against a reference standard calibrated by the National Institute of Standards and Technology (NIST). Before the development of the calibration facility, solar irradiance instruments would frequently return different measurements from each other, depending on their calibration. To maintain a long-term record of the sun's output through time, scientists had to rely on overlapping measurements that allowed them to intercalibrate among instruments.

Kopp said, "The calibration facility indicates that the TIM is producing the most accurate total solar irradiance results to date, providing a baseline value that allows us to make the entire 32-year record more accurate. This baseline value will also help ensure that we can maintain this important climate data record for years into the future, reducing the risks from a potential gap in spacecraft measurements."

Lean said, "We are eager to see how this lower irradiance value affects global climate models, which use various parameters to reproduce current climate: incoming solar radiation is a decisive factor. An improved and extended solar data record will make it easier for us to understand how fluctuations in the sun's energy output over time affect temperatures, and how Earth's climate responds to radiative forcing."

Lean's model, which is now adjusted to the new lower absolute TSI values, reproduces with high fidelity the TSI variations that TIM observes and indicates that solar irradiance levels during the recent prolonged solar minimum period were likely comparable to levels in past solar minima. Using this model, Lean estimates that solar variability produces about 0.1o Celsius (0.18o Fahrenheit) global warming during the 11-year solar cycle, but is likely not the main cause of global warming in the past three decades.

Greg Kopp
(303) 735-0934
Greg.Kopp@lasp.colorado.edu

Judith Lean
(202) 767 5116
jlean@ssd5.nrl.navy.mil

AGU Contact:
Peter Weiss
pweiss@agu.org

CU-Boulder LASP Contact:
Stephanie Renfrow
Stephanie.renfrow@lasp.colorado.edu

CU-Boulder Contact:
Jim Scott
Jim.Scott@Colorado.edu

NRL Contact:
Donna McKinney
donna.mckinney@nrl.navy.mil

December 16, 2010

Wind turbines in Midwestern farm fields may be doing more than churning out electricity. The giant turbine blades that generate renewable energy might also help corn and soybean crops stay cooler and drier, help them fend off fungal infestations and improve their ability to extract growth-enhancing carbon dioxide from the air and soil.

The preliminary findings of a months-long study that examines how wind turbines on farmlands interact with surrounding crops were presented today at the annual fall meeting of the American Geophysical Union in San Francisco. The presentation was made by researcher Gene Takle of the U.S. Department of Energy's Ames Laboratory and Julie Lundquist, assistant professor in the University of Colorado at Boulder's atmospheric and oceanic studies department.

"We've finished the first phase of our research, and we're confident that wind turbines do produce measureable effects on the microclimate near crops," said agricultural meteorology expert Takle, who also is the director of the Climate Science Program at Iowa State University.

According to Takle, turbine blades channel air downward, in effect bathing the crops below with the increased airflow they create.

"Our laser instrument could detect a beautiful plume of increased turbulence that persisted even a quarter-mile downwind of a turbine," said Lundquist, who also is a joint appointee at the U.S. Department of Energy's National Renewable Energy Laboratory, and a fellow of the Renewable and Sustainable Energy Institute, a joint institute of CU-Boulder and NREL.

Lundquist's team uses a specialized laser known as lidar to measure winds and turbulence from near the Earth's surface to well above the uppermost tip of a turbine blade.

Both Lundquist and Takle stressed their early findings have yet to definitively establish whether or not wind turbines are beneficial to the health and yield potential of soybeans and corn planted nearby. However, their finding that the turbines increase airflow over surrounding crops suggests this is a realistic possibility.

"Because wind turbines generate turbulence and the mixing of air downwind, they may accelerate the natural exchange processes between crops and the lower part of the atmosphere," said Lundquist.

For example, the sun warms crops and some of that heat is given off to the atmosphere. Extra air turbulence likely speeds up this heat exchange, so crops may stay slightly cooler on hot days, Lundquist said. On cold nights, the turbulence created by the wind turbines stirs the lower atmosphere and keeps nighttime temperatures around the crops warmer.

"In both the spring and in the fall, we suspect that turbines' effects are beneficial by warming and perhaps preventing a frost, thus extending the growing season," said Lundquist.

Wind turbines also may have positive effects on crop moisture levels. Extra turbulence may help dry the dew that settles on plants, minimizing the amount of time fungi and toxins can grow on plant leaves. Additionally, drier crops at harvest help farmers reduce the cost of artificially drying corn or soybeans.

Another potential benefit to crops is that increased airflows could enable corn and soybean plants to more readily extract CO2, a needed fuel for crops, from the atmosphere and the soil, thus helping the crops' ability to perform photosynthesis.

Takle's wind turbine predictions are based on years of research on so-called agricultural shelter belts, which are rows of trees in a field designed to slow high-speed natural winds.

"In a simplistic sense, a wind turbine is nothing more than a tall tree with a well-pruned stem," said Takle. "For a starting point for this research, we adapted a computational fluid model that we use to understand trees, but we plan to develop a new model specific to wind turbines as we gather more data."

The team's initial measurements consisted of visual observations of wind turbulence upwind and downwind of the turbines. The team also used wind-measuring instruments called anemometers to determine the intensity of the turbulence. The bulk of the wind-turbulence measurements and the crop-moisture, temperature and CO2 measurements took place in the spring and summer of this year.

"We anticipate the impact of wind turbines to be subtle, but in certain years and under certain circumstances the effects could be significant," said Takle. "When you think about a summer with a string of 105-degree days, extra wind turbulence from wind turbines might be helpful. If turbines can bring the temperature down below 100 degrees that could be a big help for crops."

The CU-Boulder and ISU teams hope to continue their measurements throughout the next growing season.

"These data are quite encouraging, and we look forward to collecting more data to ensure the certainty of these results," said Lundquist. "As wind energy expands in future years to provide a domestic source of energy, we'll need robust measurements to understand and predict the impacts of that expansion."

The research was funded or supported by Ames Laboratory, the Department of Energy's Office of Energy Efficiency and Renewable Energy, the U.S. National Laboratory for Agriculture and the Environment, CU-Boulder and NREL.

To view a video of Takle discussing the study of wind turbines on farmland visit www.youtube.com/watch?v=r7qNNvYVKI4&feature=player_embedded

Contact
Julie Lundquist, 303-492-8932
julie.lundquist@colorado.edu

Elizabeth Lock, 303-492-3117
elizabeth.lock@colorado.edu

December 15, 2010

Rising concentrations of zinc in a waterway on Colorado's Western Slope may be the result of climate change that is affecting the timing of annual snowmelt, says a new study led by the University of Colorado at Boulder.

The study focused on the Snake River watershed just west of the Continental Divide near Keystone, Colo., where CU-Boulder researchers have observed a four-fold increase in dissolved zinc over the last 30 years during the lowest water flow months, said Caitlin Crouch. Crouch, a master's degree student who led the study, said the high levels of zinc affect stream ecology, including deleterious effects on microbes, algae, invertebrates and fish.

The team speculated the increased zinc concentrations may be tied to changes in groundwater conditions and stream flow patterns caused by climate change and the associated snowmelt that has been peaking two to three weeks earlier than normal in recent years, largely because of warming air temperatures. The result is lowered stream flows and drier soils along the stream in September and October, which increases metal concentrations, said Crouch.

"While most of the talk about climate change in western waterways is about decreasing water quantities, we are evaluating potential climate influences on water quality, which is a whole different ball game," she said.

Crouch gave a presentation on the subject at the fall meeting of the American Geophysical Union held in San Francisco Dec. 13-17. The study was co-authored by Professor Diane McKnight of CU-Boulder's civil and environmental engineering department.

The zinc in the Snake River watershed is primarily a result of acid rock drainage, or ARD, which can come from abandoned mine sites along rivers or through the natural weathering of pyrite in the local rock, said Crouch. Sometimes enhanced by mining activity, weathering pyrite forms sulfuric acid through a series of chemical reactions, which dissolves metals like zinc and carries them into the groundwater.

McKnight, also a fellow of CU-Boulder's Institute of Arctic and Alpine Research, said there are nearly 2,000 miles of waterways in Colorado affected by ARD.

One of the most noticeable impacts of ARD in the Upper Snake River drainage is on the fishery downstream, said Crouch, a graduate student in CU-Boulder's Environmental Studies Program. Rainbow trout populations in much of the river are not self-sustaining because of ecologically harsh stream conditions, and the waterway requires stocking several times a year.

The elevated zinc in the Snake River comes from several ARD sources, said Crouch. Crouch's study site -- where an increasing trend in zinc concentrations is sustained by groundwater discharge -- is above the Peru Creek tributary to the Snake River, where natural pyrite weathering is thought to be the main source of ARD. Peru Creek is largely devoid of life due to ARD from the abandoned Pennsylvania Mine and other smaller mines upstream and has been a target for potential remediation efforts.

McKnight said another factor involved in rising zinc levels in the Snake River watershed -- which runs from the top of the Continental Divide to Dillon Reservoir -- could be the result of the severe 2002 drought in Colorado. The drought significantly lowered waterways, allowing more pyrite to be weathered in dry soils of the watershed and in wetlands adjacent to the stream.

As part of her study, Crouch measured zinc concentrations in an alpine tributary of the Upper Snake River. She found that zinc concentrations there were 10 times higher than in the main stem of the waterway and correlated with increased sulfate, so-called "hard water" containing calcium and magnesium, and a variety of metals.

"This supports our contention that the increasing zinc concentrations we are seeing in the watershed are driven by the acceleration of ARD," Crouch said. "One of the things I still am trying to parse out is whether metals like zinc are coming from one discrete source or are being diffused into the watershed from the groundwater beneath."

Cleaning up abandoned, polluted mines like the Pennsylvania Mine remains a problem largely because of liability issues since the mine owners who normally would be responsible for the mine cleanup are long gone. The Environmental Protection Agency has begun an agency-wide effort to reduce barriers to the cleanup of abandoned mine sites by local environmental groups and volunteers.

In the case of the Pennsylvania Mine, the Snake River Task Force is working with partners like the Keystone Ski Resort, the Keystone Center, Trout Unlimited, the Northwest Colorado Council of Governments, Summit County, the Colorado Department of Public Health and Environment, the EPA and the Blue River Watershed Group.

Seven CU-Boulder graduate students have produced master's and doctoral theses under McKnight on environmental issues related to the Snake River watershed. Copies of the studies have been provided to the Snake River Task Force to help assess the current and future stream chemistry and biology in the area.

Contact

Caitlin Crouch, 619-987-4030
Caitlin.Crouch@colorado.edu
Diane McKnight, 303-492-4687
Diane.McKnight@colorado.edu
Jim Scott, 303-492-3114
Jim.Scott@colorado.edu

December 14, 2010

A novel project using cameras mounted on unmanned aircraft flying over the Arctic is serving double duty by assessing the characteristics of declining sea ice and using the same aerial photos to pinpoint seals that have hauled up on ice floes.

The project is the first to use aircraft to monitor ice and seals in remote areas without putting pilots and observers at risk, said Elizabeth Weatherhead of the University of Colorado at Boulder, who is leading the study team. Weatherhead is a senior scientist at the Cooperative Institute for Research in Environmental Sciences, a joint venture of CU-Boulder and the National Oceanic and Atmospheric Administration.

Monitoring the seals is important because the Arctic is rapidly warming as a result of human-produced greenhouse gases building up in Earth's atmosphere, according to climate scientists. Warming temperatures and sea ice loss are of concern to biologists because they are impacting at least some Arctic marine and terrestrial mammals.

"Because ice is diminishing more rapidly in some areas than others, we are trying to focus on what areas and types of ice the seals need for their survival," said Peter Boveng, leader of the Polar Ecosystems Program at NOAA's Alaska Fisheries Science Center.

"By finding the types of ice they prefer, we can keep track of that ice and see how it holds up as the Arctic sea ice extent shrinks," said Weatherhead.

Weatherhead gave a presentation on the subject at the fall meeting of the American Geophysical Union held in San Francisco Dec. 13 to Dec. 17. Other scientists involved in the project include Boveng, Robyn Angliss, deputy director of NOAA's National Marine Mammal Laboratory in Seattle, NMML researchers Michael Cameron and Erin Moreland, and the University of Alaska Fairbanks' Greg Walker.

The four species of Arctic seals of most interest to the research team are the bearded, ringed, spotted and ribbon seals, each of which rely in some way on sea ice for breeding, resting and as a safe haven from predators.

Known as the "Scan Eagle," the unmanned aircraft was launched in May and June of 2009 from the NOAA vessel McArthur II over the Bering Sea west of Alaska. The drone has a 10-foot wingspan and is owned and operated by the University of Alaska.

The image recognition software was developed by Boulder Labs Inc. in Boulder, Colo., and used to automate the identification of seals in 27,000 images that were collected during the flights. "The results show that the seals have distinct preferences for specific types of ice, demonstrating that ice extent is not the only factor affecting seal populations," said Weatherhead.

The Scan Eagle flights lasted from two to eight hours and flew at altitudes ranging from 300 to 1,000 feet. While the amount of ocean and ice scanned by the unmanned aircraft was small -- it flew 3- to 5-mile-long transects over the Bering Sea -- the researchers were eager to see whether the image recognition system would work for characterizing both the ice and the seals. "The answer was a resounding yes," Weatherhead said.

The analysis of sea ice by the team included edge-to-area calculations of ice floes as well as ice floe size and distribution. "There is an incredible variety of ice and we are trying to come up with mathematical ways to describe it," she said. "One thing that really interests us is how broken up the ice is in particular areas."

According to CU-Boulder's National Snow and Ice Data Center, the total loss of Arctic sea ice extent from 1979 to 2009 was an area larger than the state of Alaska. Scientists there believe the Arctic may become ice-free during the summers within the next several decades.

In December 2010, NOAA's Fisheries Service proposed to list the Arctic ringed seal as threatened under the Endangered Species Act because of diminishing sea ice and snow cover. Arctic ringed seals do not come ashore, but use sea ice for whelping, nursing and resting. Ringed seal pups are born in snow caves on the ice, and their survival can be affected by snow depths and the timing of spring snowmelt and ice breakup.

"Biologists are thrilled about the image recognition software because it could change the way we monitor seal populations," said Weatherhead. "We can send an unmanned craft out from a ship, collect 4,000 images, and have them analyzed before dinner. This is a great example of physicists working closely with biologists who are concerned with the health of seal populations."

Typically, seals appear in less than 1 percent of the images, said Weatherhead. But on the ice floes or ice edges where they are found, the software can help researchers identify seals by species. In the future, researchers might be able to identify the relative age and gender for some seal species. The software could even be adjusted to look for polar bears and their tracks.

Weatherhead said the team wants to combine its results with forecasts not only of future sea ice extents, but also of future ice characteristics that will allow for predictions regarding the impacts of changing and disappearing ice types on seal populations.

CIRES has even turned the project into a middle school game akin to "Where's Waldo" by posting aerial images of ice floes from the air and challenging students to try to find the seals. Visit the website at cires.colorado.edu/blogs/hmm/2010/09/09/find-the-seals/.

To view a short video of the project visit www.colorado.edu/news and click on the story headline.

For more information on CU-Boulder visit www.colorado.edu/. For more information on CIRES visit cires.colorado.edu/. For more information on NOAA visit www.noaa.gov/

Contact

Elizabeth Weatherhead, 303-497-6653
Elizabeth.Weatherhead@colorado.edu

November 3, 2010

Melt water flowing through ice sheets via crevasses, fractures and large drains called moulins can carry warmth into ice sheet interiors, greatly accelerating the thermal response of an ice sheet to climate change, according to a new study involving the University of Colorado at Boulder.

The new study showed ice sheets like the Greenland Ice Sheet can respond to such warming on the order of decades rather than the centuries projected by conventional thermal models. Ice flows more readily as it warms, so a warming climate can increase ice flows on ice sheets much faster than previously thought, said the study authors.

"We are finding that once such water flow is initiated through a new section of ice sheet, it can warm rather significantly and quickly, sometimes in just 10 years, " said lead author Thomas Phillips, a research scientist with Cooperative Institute for Research in Environmental Sciences. CIRES is a joint institute between CU-Boulder and the National Oceanic and Atmospheric Administration.

Phillips, along with CU-Boulder civil, environmental and architectural engineering Professor Harihar Rajaram and CIRES Director Konrad Steffen described their results in a paper published online this week in Geophysical Research Letters.

Conventional thermal models of ice sheets do not factor in the presence of water within the ice sheet as a warming agent, but instead use models that primarily consider ice-sheet heating by warmer air on the ice sheet surface. In water's absence, ice warms slowly in response to the increased surface temperatures from climate change, often requiring centuries to millennia to happen.

But the Greenland ice sheet is not one solid, smooth mass of ice. As the ice flows towards the coast, grating on bedrock, crevasses and new fractures form in the upper 100 feet of the ice sheet. Melt water flowing through these openings can create "ice caves" and networks of "pipes" that can carry water through the ice and spreading warmth, the authors concluded.

To quantify the influence of melt water, the scientists modeled what would happen to the ice sheet temperature if water flowed through it for eight weeks every summer -- about the length of the active melt season. The result was a significantly faster-than-expected increase in ice sheet warming, which could take place on the order of years to decades depending on the spacing of crevasses and other "pipes" that bring warmer water into the ice sheet in summer.

"The key difference between our model and previous models is that we include heat exchange between water flowing through the ice sheet and the ice," said Rajaram.

Several factors contributed to the warming and resulting acceleration of ice flow, including the fact that flowing water into the ice sheets can stay in liquid form even through the winter, slowing seasonal cooling. In addition, warmer ice sheets are more susceptible to increases of water flow, including the basal lubrication of ice that allows ice to flow more readily on bedrock.

A third factor is melt water cascading downward into the ice, which warms the surrounding ice. In this process the water can refreeze, creating additional cracks in the more vulnerable warm ice, according to the study.

Taken together, the interactions between water, temperature, and ice velocity spell even more rapid changes to ice sheets in a changing climate than currently anticipated, the authors concluded. After comparing observed temperature profiles from Greenland with the new model described in the paper, the authors concluded the observations were unexplainable unless they accounted for warming.

"The fact that the ice temperatures warm rather quickly is really the key piece that's been overlooked in models currently being used to determine how Greenland responds to climate warming," Steffen said. "However, this process is not the ‘death knell' for the ice sheet. Even under such conditions, it would still take thousands of years for the Greenland ice sheet to disappear, Steffen said.

This study was funded by NASA's Cryosphere Science Program.

Contact

Thomas Phillips, 303-492-4829
Thomas.Phillips@colorado.edu
Harihar Rajaram, 303-4926604
Konrad Steffen, 303-492-8773
Konrad.Steffen@colorado.edu
Morgan Heim, CIRES Communication, 303-492-6289
Morgan.Heim@colorado.edu

Fire and forest ecologist Tania Schoennagel and her colleagues Thomas Veblen and others conducted studies of the forests west of Boulder before the devastating Fourmile Canyon Fire erupted on September 6th, 2010. By the time the Fourmile Fire was fully contained about a week later, it had become the most destructive fire in Colorado history. Schoennagel discussed the fire, results from their studies, and ideas for future fire mitigation in an extended interview with Ryan Warner of Colorado Public Radio on 15 September.

During the interview Schoennagel notes that the forests west of Boulder were ripe for a severe fire, primarily because many of the forests in the area are naturally dense, with only minimal effects of past fire suppression on forest density. Moreover, her research shows that these forests have a long history of fire, including severe fire events. She and her colleagues identified fire scars in tree rings to create a history of past fires. Their data identifed many fire events, including severe fires that destroyed the town of Gold Hill in 1860 and another than nearly destroyed the town again in 1894. Both fires occurred during a prolonged dry period in the late 1800's.

Schoennagel and Warner discuss many topics including the difficulties of coordinating fire mitigation efforts on a patchwork of public and private lands, the expected increase in damaging wildfires in the Wildland-Urban Interface associated with increasing population and changing climate, and ideas for reducing the damage of future wildfires.

http://instaar.colorado.edu/research/science_spotlights.html#pjbr

October 20, 2010

PHOENIX, AZ—At a meeting of water leaders from the seven Colorado River Basin states in Phoenix today, Secretary of the Interior Ken Salazar announced that the Department of the Interior has chosen the University of Arizona as home base for a regional Climate Science Center and selected the Colorado River Basin for the launch of the first U.S. water census since 1978.

“The Colorado River Basin is ground zero for assessing the effects of climate change on our rivers and taking creative management actions to head off the related dangers posed to our water supplies, hydroelectric power generation and ecosystems,” the Secretary said. “We are with you for the long haul to protect our region and its water.”

The Southwest Climate Center is the fourth of eight planned regional Climate Science Centers—or CSCs--to be established by the Department. With the University of Arizona in Tucson as home base, the center will be led by a consortium of that school and others -- University of California, Davis; University of California, Los Angeles; Desert Research Institute, Reno; University of Colorado, Boulder; and the Scripps Institution of Oceanography at the University of California, San Diego.

“The consortium headed by the University of Arizona brings a wide range of scientific and impact assessment capabilities to the Southwest Climate Center because it includes institutions located in and familiar with the incredible diversity of ecosystems and human settlements and activities that characterize the U.S. Southwest,” the Secretary noted. The consortium is well versed in issues such as coastal management, drought and its impacts on people and the environment, water management in the Colorado and other Southwest rivers, and the impacts of exploding populations of bark beetles on western forests.

Selected through an open competition, the six universities announced today host the Southwest Climate Alliance, which has a combined world-class scientific expertise–including hundreds of faculty working on climate- and resource-related work essential for meeting the climate challenge. In addition to the six host institutions, the Southwest Climate Alliance also includes the following as partners: Arizona State University; Northern Arizona University; University of California, Merced; University of Nevada, Las Vegas; NASA Ames Research Center, Calif.; and the U.S. Institute for Environmental Conflict Resolution, Tucson.

In addition to the climate center announcement, the Secretary told water leaders that today’s meeting also marked the launch of the Colorado River Basin Geographic Focus Study by the U.S. Geological Survey (USGS)—Interior’s scientific experts.

The study is part of the WaterSMART Water Availability and Use Assessment for the Colorado River Basin. It is planned as a three-year, $1.5 million effort that will provide an inventory of water supply and demand, including water needed to support ecosystems, and report on significant competition over water resources and the factors causing that competition. (The “SMART” in WaterSMART stands for “Sustain and Manage America’s Resources for Tomorrow.”)

“You can’t manage a resource that you don’t measure,” Salazar said. “The WaterSMART initiative is all about measuring our water supplies and how we use them. This water census will provide crucial information to water managers to improve our efforts to wisely balance competing demands.”

BACKGROUND ON CLIMATE SCIENCE CENTERS

The Department of the Interior previously announced:

    * The Alaska Climate Science Center hosted by the University of Alaska-Fairbanks in Anchorage.
    * The Southeast Climate Science Center hosted by North Carolina State University
    * The Northwest Climate Science Center led by a consortium of three universities--Oregon State University, University of Washington and the University of Idaho.

Today’s announcement covered:

    * The Southwest Climate Science Center—University of Arizona, Tucson; University of California, Davis; University of California, Los Angeles; Desert Research Institute, Reno; University of Colorado, Boulder ; and the Scripps Institution of Oceanography at the University of California in San Diego. In addition to the six host institutions, the CSC also includes the following as partners: Arizona State University; Northern Arizona University; University of California, Merced; University of Nevada, Las Vegas; NASA Ames Research Center, Calif.; and the U.S. Institute for Environmental Conflict Resolution, Tucson.

Announcements to come include:

    * The North Central Climate Science Center—announcement by end of October
    * The Northeast, South Central, and Pacific Islands Climate Science Centers-- Interior intends to invite proposals in the spring of 2011 to host the remaining regional centers
    * Secretary Salazar initiated a coordinated climate change strategy in September 2009, with Secretarial Order 3289. The order called for establishing not only regional CSCs but also a network of “Landscape Conservation Cooperatives” that engage federal agencies, local and state partners, and the public in crafting practical, landscape-level strategies for managing climate change impacts on natural resources. Twenty-one LCCs are planned through FY 2012.

The CSCs will serve as regional “hubs” of the National Climate Change and Wildlife Science Center, located at the headquarters of Interior’s U.S. Geological Survey. USGS is taking the lead on establishing the CSCs and providing initial staffing. Ultimately, funds and staff from multiple Interior bureaus will be pooled to support these centers and ensure collaborative sharing of research results and data. Together, the CSCs and Landscape Conservation Cooperatives will assess the impacts of climate change that typically extend beyond the borders of any single national wildlife refuge, national park or Bureau of Land Management unit and identify strategies to ensure that resources across landscapes are resilient.

BACKGROUND ON USGS COLORADO RIVER BASIN GEOGRAPHIC FOCUS STUDY AND NEW NATIONAL WATER CENSUS

This Colorado River Basin Geographic Focus Study is part of the ongoing effort outlined in the WaterSMART Secretarial Order signed in February 2010. It reflects a national commitment to understanding water availability in the country and managing that resource for current and future generations. The last comprehensive assessment of water availability for our nation was in 1978 and it is overdue for a new one.

The USGS WaterSMART initiative will produce a water census for the nation, a new and on-going appraisal for water availability that links both water quality and quantity, tracks changing flow, use, and storage of water, as well as developing models and predictive tools to guide its decisions . A relatively new area of science evaluates how much water needs to be left in the streams to support important ecological values. This initiative includes a significant research and assessment effort to help wildlife managers characterize the flow needs for aquatic species and their habitat. Knowing our nation’s water “assets” and rates of use on an ongoing basis is crucial to wise management.

The USGS WaterSMART Colorado River Basin Geographic Focus Study will complement the River Basin Supply and Demand grant awarded for the Colorado Basin by the Bureau of Reclamation in 2010 and is one of three such studies on major river basins across the nation planned to begin this year. Future geographic focus areas will be identified through the application of criteria being developed as part of the implementation plan for the USGS strategic science direction focused on our nation’s water resources. A critical first step will be meetings with Colorado River Basin stakeholders to collaboratively develop a detailed scope for the effort.

Contact: Joan Moody, DOI (202) 208-6416

http://www.doi.gov/news/pressreleases/Secretary-Salazar-Launches-New-Regional-Climate-Science-Center-and-Water-Census-at-Meeting-of-Colorado-River-Basin-Water-Leaders.cfm