Posts tagged NSIDC
Arctic sea ice reaches lowest extent ever recorded, says CU-Boulder research team
Aug 27th
The blanket of sea ice floating on the Arctic Ocean melted to its lowest extent ever recorded since satellites began measuring it in 1979, according to the University of Colorado Boulder’s National Snow and Ice Data Center.
On Aug. 26, the Arctic sea ice extent fell to 1.58 million square miles, or 4.10 million square kilometers. The number is 27,000 square miles, or 70,000 square kilometers below the record low daily sea ice extent set Sept. 18, 2007. Since the summer Arctic sea ice minimum normally does not occur until the melt season ends in mid- to late September, the CU-Boulder research team expects the sea ice extent to continue to dwindle for the next two or three weeks, said Walt Meier, an NSID scientist.
“It’s a little surprising to see the 2012 Arctic sea ice extent in August dip below the record low 2007 sea ice extent in September,” he said. “It’s likely we are going to surpass the record decline by a fair amount this year by the time all is said and done.”
On Sept. 18, 2007, the September minimum extent of Arctic sea ice shattered all satellite records, reaching a five-day running average of 1.61 million square miles, or 4.17 million square kilometers. Compared to the long-term minimum average from 1979 to 2000, the 2007 minimum extent was lower by about a million square miles — an area about the same as Alaska and Texas combined, or 10 United Kingdoms.
While a large Arctic storm in early August appears to have helped to break up some of the 2012 sea ice and helped it to melt more quickly, the decline seen in in recent years is well outside the range of natural climate variability, said Meier. Most scientists believe the shrinking Arctic sea ice is tied to warming temperatures caused by an increase in human-produced greenhouse gases pumped into Earth’s atmosphere.
CU-Boulder researchers say the old, thick multi-year ice that used to dominate the Arctic region has been replaced by young, thin ice that has survived only one or two melt seasons — ice which now makes up about 80 percent of the ice cover. Since 1979, the September Arctic sea ice extent has declined by 12 percent per decade.
The record-breaking Arctic sea ice extent in 2012 moves the 2011 sea ice extent minimum from the second to the third lowest spot on record, behind 2007. Meier and his CU-Boulder colleagues say they believe the Arctic may be ice-free in the summers within the next several decades.
“The years from 2007 to 2012 are the six lowest years in terms of Arctic sea ice extent in the satellite record,” said Meier. “In the big picture, 2012 is just another year in the sequence of declining sea ice. We have been seeing a trend toward decreasing minimum Arctic sea ice extents for the past 34 years, and there’s no reason to believe this trend will change.”
The Arctic sea ice extent as measured by scientists is the total area of all Arctic regions where ice covers at least 15 percent of the ocean surface, said Meier.
Scientists say Arctic sea ice is important because it keeps the polar region cold and helps moderate global climate — some have dubbed it “Earth’s air conditioner.” While the bright surface of Arctic sea ice reflects up to 80 percent of the sunlight back to space, the increasing amounts of open ocean there — which absorb about 90 percent of the sunlight striking the Arctic — have created a positive feedback effect, causing the ocean to heat up and contribute to increased sea ice melt.
Earlier this year, a national research team led by CU embarked on a two-year effort to better understand the impacts of environmental factors associated with the continuing decline of sea ice in the Arctic Ocean. The $3 million, NASA-funded project led by Research Professor James Maslanik of aerospace engineering sciences includes tools ranging from unmanned aircraft and satellites to ocean buoys in order to understand the characteristics and changes in Arctic sea ice, including the Beaufort Sea and Canada Basin that are experiencing record warming and decreased sea ice extent.
NSIDC is part of CU-Boulder’s Cooperative Institute for Research in Environmental Sciences — a joint institute of CU-Boulder and the National Oceanic and Atmospheric Administration headquartered on the CU campus — and is funded primarily by NASA. NSIDC’s sea ice data come from the Special Sensor Microwave Imager/Sounder sensor on the Defense Meteorological Satellite Program F17 satellite using methods developed at NASA’s Goddard Space Flight Center in Greenbelt, Md.
For more information and graphics visit CU-Boulder’s NSIDC website at http://nsidc.org/arcticseaicenews/2011/091511.html. For more information on CIRES visithttp://cires.colorado.edu/.
CU scientists study high-Asian snowpack for GW clues
Dec 7th
WATER RESOURCES IN ASIA MOUNTAINS
A University of Colorado Boulder team is partnering with the United States Agency for International Development to assess snow and glacier contributions to water resources originating in the high mountains of Asia that straddle 10 countries.
Richard Armstrong and Mark Williams, the two faculty members leading the four-year study, said the aim is to provide a comprehensive and systematic assessment of freshwater resources in the so-called “High Asia” region, which encompasses five mountain ranges and watersheds totaling roughly 1 million square miles. The area under study is roughly equal to one-third of the contiguous United States.
This assessment will be crucial in helping to forecast the future availability and vulnerability of water resources in the region, beginning with accurate assessments of the distinct, separate contributions to river discharge from melting glacier ice and seasonal snow. Such data ultimately will provide a better understanding of the timing and volume of runoff in the face of climate change, said the CU-Boulder researchers.
The High Asia mountains funnel water into such major river basins as the Ganges, Brahmaputra, Indus, Amu Darya and Syr Darya. The High Asian mountain ranges under study include the Himalaya, Karkoram, Hindu Kush, Pamir and Tien Shan. The mountain ranges straddle Bhutan, Nepal, China, India, Pakistan, Afghanistan, Kazakhstan, Uzbekistan, Kyrgyzstan and Tajikistan.
Through the partnership, scientists and students within the 10 countries will carry out collaborative research with CU-Boulder scientists. The project also will support satellite data processing by CU-Boulder staff and trainings for local institutions and observers within the study area to collect water and precipitation samples for the project.
While about one-third of the world’s population depends to some degree on fresh water within the High Asia hydrological system, not enough data exists on river and stream flows and the contribution of seasonal snow and glacier melt to paint an accurate picture of the water resources there, said Armstrong, a senior research scientist at CU-Boulder’s National Snow and Ice Data Center, or NSIDC. ”
The team requires an accurate quantitative portrait of each major river basin and sub-basin in High Asia. The Indus River, for example, which is fed by waterways from the Himalaya, Karakorum and Hindu Kush mountain ranges, comes together at the city of Besham, Pakistan, “where it immediately turns into the largest irrigation system in the world,” said Williams. “The sources of water in High Asia feeding the major foothill regions where most of the people live are really the crux of this study.”
Armstrong said there is a lot of misinformation in the public arena regarding glaciers, including reports that glaciers in the Himalaya are receding faster than anywhere else in the world and, if this rapid melting continues, rivers are on track to first flood and then dry up. “Those reports simply are not true,” Armstrong said.
USAID is an independent United States government agency that provides economic, development and humanitarian assistance around the world in support of the foreign policy goals of the United States.
“USAID wants to know how the High Asia water resources affect local populations,” said Armstrong, also a fellow at the CU-headquartered Cooperative Institute for Research in Environmental Sciences. “They are looking at this challenge from a sustainability perspective, including what is going to happen to rivers like the Indus and the Brahmaputra in the next 20 years.”
The researchers will use remote-sensing satellite data from NASA, the European Space Agency and the Japanese Space Agency to develop time-series maps of seasonal snowfall amounts and recent changes in glacier extent, said Williams, a fellow at CU-Boulder’s Institute of Arctic and Alpine Research and a CU-Boulder geography professor. They also will use local meteorological and river discharge data from throughout the High Asia study area.
“What’s really driving this study are questions about water security,” said Williams. “There is a lot of international interest in accurate water resource data from the High Asia region and what the water security consequences are, since water conflicts between countries can escalate rapidly. This study should provide answers as to what is real and what is false.”
“Once we have a picture of recent and current conditions, we can go forward and run computer ‘melt models’ based on the temperatures at various elevations, giving us trends in snowmelt and glacier melt by region and time,” said Armstrong. “That’s when we start to come up with water volumes for individual rivers and streams from both melting snow and ice.”
The modeling results will be verified using geochemical and water isotope “tracer” techniques developed at CU that allow researchers to follow water as it courses through mountain landscapes. Previous studies by Williams and his research group showed high mountain groundwater in Colorado dominated by snowmelt can be locked underground for decades before emerging into downstream waterways. “These isotopic and geochemical measurements provide unique fingerprints, allowing a CSI-like approach to tracing water sources,” said Williams.
Critical to the project is the university’s expertise in remote sensing research through NSIDC — including assessing changes in Earth’s snow and ice cover — and INSTAAR’s research on the physical, chemical and biological processes in “critical zones,” which are the areas between treetops and groundwater. INSTAAR administers both the Long-Term Ecological Research site at Niwot Ridge west of Boulder and the Critical Zone Observatory project in the Boulder Creek watershed for the National Science Foundation.
One of the biggest project challenges will be to obtain data from some of the most remote regions on Earth, said Williams. The water, rain and snow samples collected by collaborators within the study area will be sent back to CU-Boulder for analysis.
The research will bring together scientists and government officials in the countries of High Asia to coordinate and compare results on what part of river flows come from glaciers and seasonal snow. This sharing of information is important because the rivers of Asia can cross several country borders. USAID support will contribute to the research and coordination and CU-Boulder will make its archived and new data on snow and ice easily available to all the countries and their citizens.
The CU team will hire Asian project managers and collaborate with research scientists affiliated with various Asian institutes. “We already have some good scientific contacts in the region, people we know who are reliable and who can deliver,” said Armstrong.
A number of CU undergraduate and graduate students will be involved in the study and support will be available to Asian students by way of the funding provided to Asian project partners.
“One of the main project goals is to transfer scientific understanding to people in the region who can continue these measurements and analysis once the USAID project is finished,” said Armstrong. “The idea is to provide the local population with the information they need to make decisions that will increase sustainability as land use and climate change.
Boulder CU: Arctic sea ice all-time low
Sep 15th
THE SECOND LOWEST IN THE SATELLITE RECORD
The blanket of sea ice that floats on the Arctic Ocean appears to have reached its lowest extent for 2011, the second lowest recorded since satellites began measuring it in 1979,
The Arctic sea ice extent fell to 1.67 million square miles, or 4.33 million square kilometers on Sept. 9, 2011.
While this year’s September minimum extent was greater than the all-time low in 2007, it remains significantly below the long-term average and well outside the range of natural climate variability, according to scientists involved in the analysis. Most scientists believe the shrinking Arctic sea ice is tied to warming temperatures caused by an increase in human-produced greenhouse gases pumped into Earth’s atmosphere.
“Every summer that we see a very low ice extent in September sets us up for a similar situation the following year,” said NSIDC Director Mark Serreze, also a professor in CU-Boulder’s geography department. “The Arctic sea ice cover is so thin now compared to 30 years ago that it just can’t take a hit anymore. This overall pattern of thinning ice in the Arctic in recent decades is really starting to catch up with us.”
Serreze said that in 2007, the year of record low Arctic sea ice, there was a “nearly perfect” set-up of specific weather conditions. Winds pushed in more warm air over the Arctic than usual, helping to melt sea ice, and winds also pushed the floating ice chunks together into a smaller area. “It is interesting that this year, the second lowest sea ice extent ever recorded, that we didn’t see that kind of weather pattern at all,” he said.
The last five years have been the five lowest Arctic sea ice extents recorded since satellite measurements began in 1979, said CU-Boulder’s Walt Meier, an NSIDC scientist. “The primary driver of these low sea ice conditions is rising temperatures in the Arctic, and we definitely are heading in the direction of ice-free summers,” he said. “Our best estimates now indicate that may occur by about 2030 or 2040.”
There still is a chance the sea ice extent could fall slightly due to changing winds or late season melt, said Meier. During the first week of October, CU-Boulder’s NSIDC will issue a full analysis of the 2011 results and a comparison to previous years.
NSIDC is part of CU-Boulder’s Cooperative Institute for Research in Environmental Sciences — a joint institute of CU-Boulder and the National Oceanic and Atmospheric Administration headquartered on the CU campus — and is funded primarily by NASA.
NSIDC’s sea ice data come from the Special Sensor Microwave Imager/Sounder sensor on the Defense Meteorological Satellite Program F17 satellite using methods developed at NASA’s Goddard Space Flight Center in Greenbelt, Md.





















