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Coastal Sector Assessment Report Released
Report Examines Impacts of Climate Change on Coastal Areas and Marine Resources
The National Oceanic and Atmospheric Administration's National Ocean Service released a new report titled, "The Potential Impacts of Climate Change on Coastal and Marine Resources," that concludes that climate changes in this century may have serious implications for U.S. coastal and marine resources.

NOAA scientists are concerned. With a coastline of over 95,000 miles and a dependency on the essential goods and services that it provides, the adaptation of the marine environment to climate change is important. According to scientists, climate change will add to the stresses already occurring to coastal and marine resources, as a result of increasing coastal populations, development pressure and habitat loss, over fishing, nutrient enrichment, pollution and invasive species.

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global change data
Global Soils Data Available on CD-ROM
Data from IGBP SoilData System, soil profiles, and gridded surfaces being distributed by the ORNL DAAC
The Oak Ridge National Laboratory Distributed Active Archive Center (ORNL DAAC) now offers a CD of global soil data prepared by the Global Soil Data Task for the International Geosphere-Biosphere Programme (IGPB) Data and Information Services (DIS). The CD is entitled "Global Soil Data Products CD-ROM (IGBP-DIS)."

The new CD includes the IGBP's SoilData System, which links the Global Pedon Database to the FAO/UNESCO Digital Soil Map of the World. The system allows users to generate maps and data sets for a range of original and derived soil parameters for any part of the world at soil depths and resolutions selected by the user.

The CD also contains 1125 soil profiles that provide information about fundamental soil properties (e.g., depth, particle size distribution, bulk density, extractable nutrient composition) for soil classes based on FAO soil map legends.

In addition, the CD includes gridded global surfaces generated from the FAO Interpreted Surfaces and from the SoilData System at 5-minute (latitude/longitude) resolution. The FAO-based products indicate organic carbon density, soil water-holding capacity, and easily available water capacity. The SoilData System-based products indicate soil carbon, soil nitrogen, field capacity, wilting point, profile available water capacity, thermal capacity, and bulk density.

global change research
More El Niños and La Niñas May Lead to More Global Rainfall Extremes
Researchers at NASA and the University of Maryland, Baltimore County (UMBC), studying changes in tropical precipitation patterns, have noted a higher frequency of El Niños and La Niñas over the last 21 years. In addition, when either of those events occur, the world can expect more months with unusually high or low precipitation with droughts more common than floods over land areas. Scott Curtis of UMBC and Robert Adler of NASA/Goddard Space Flight Center are co-authors of a paper titled "The Magnitude and Variability of Global and Regional Precipitation Based on the 21 Year Global Precipitation Climatology Project (GPCP) and 3 Year Tropical Rainfall Measuring Mission (TRMM) Data Sets" being presented January 15 at the 2001 Annual Meeting of the American Meteorological Society in Albuquerque, N.M.

El Niño events occur irregularly at intervals of 2-7 years, although the average is about once every 3-4 years. Curtis said the global precipitation database shows El Niños or La Niñas occurring almost every 2 years throughout the last two decades. These events typically last 12-18 months and are accompanied by swings in the Southern Oscillation, an interannual seesaw in tropical sea level pressure between the eastern and western Pacific. El Niño/Southern Oscillation (ENSO) events are characterized by large changes in precipitation over the tropics, which extend around the globe. Curtis and Adler used data from the World Climate Research Project's Global Precipitation Climatology Project (GPCP), a database of monthly precipitation around the world, to study global and regional variations in rainfall. They compared the GPCP data to rainfall data from NASA's TRMM satellite over the tropics.

global change research
Eastern U.S. Keeps Its Cool While the World Warms
Much of the Earth has warmed over the last half-century, but the eastern half of the United States has shown a cooling trend. NASA-funded research indicates cooler temperatures in the eastern U.S. are caused by an increase in sun-shielding clouds produced by warmer ocean temperatures in the Pacific. Walter A. Robinson of the University of Illinois at Urbana-Champaign, James Hansen of NASA Goddard Institute for Space Studies, and Reto Reudy of Science Systems and Applications, Inc. will present these findings in a paper entitled "Where's the Heat? Insights From GCM Experiments into the Lack of Eastern U.S. Warming" at the American Meteorological Society Annual Meeting in Albuquerque, N.M. on January 15.

Eastern U.S. temperatures have displayed a cooling trend of 0.1° Celsius per decade, while global temperatures warmed by that same amount from 1950 to 1997. The researchers used a computer climate model to see if this regional cooling could be caused by changes in sea surface temperature. Robinson said that in the GISS model, "Warmer sea surface temperatures in the tropical Pacific cause greater cloud cover over the eastern United States. This increased cloud cover is directly responsible for the cooling." The brightness of a cloud causes a large percentage of incoming solar radiation to be reflected back into space, thus keeping the atmosphere cooler than if the cloud wasn't there. Using the climate simulations, Robinson found the amount of water vapor in the Gulf of Mexico follows closely the water vapor released by the warm sea surface temperatures in the Pacific Ocean. Water vapor from the Pacific moves east to the Gulf of Mexico and is then carried over the eastern U.S. by the clockwise circulation around an Atlantic subtropical high pressure system. When the water vapor arrives over the U.S. it condenses and generates more cloud cover, allowing less solar radiation to reach and warm the Earth's surface.

global change research
NOAA Scientist and Colleague Find Extreme Climate Event . . . Without Even Trying
When scientists run computer models to simulate climate events, they often add elements, such as effect of volcanic eruptions, adding ice sheets, or altering the concentrations of greenhouse gases in the model's atmosphere. One NOAA scientist and his colleague discovered a large, abrupt climate event without the additions. "When I first saw the results, I thought that I had bad data," said Ronald Stouffer, a meteorologist at NOAA's Geophysical Fluid Dynamics Laboratory in Princeton, N.J. "I would never would have guessed the `bad data' was a very interesting event."

The "interesting event" is a severe and abrupt cooling of the North Atlantic Ocean near Greenland. The event will be described by Stouffer and Alex Hall of the Lamont-Doherty Earth Observatory in Palisades, N.Y. in the Jan. 11 issue of the science journal Nature. Stouffer and Hall found that an unusually long-lived atmospheric wind deviation leads to the northern North Atlantic Ocean and surrounding regions becoming very cold for 30 to 40 years. "We have a 15,000-year simulation," Stouffer said. "About the model year 3,100, there is a dramatic drop in the surface air temperature. It just happened spontaneously, which is what makes the event so interesting."

Researchers at Washington State University Vancouver and Princeton University have new observations about rapid climate changes in the Northern and Southern hemispheres over the past 100,000 years that could help scientists predict future climate changes. Their article titled "Timing of Millennial-Scale Climate Change in Antarctica and Greenland During the Last Glacial Period" by Edward Brook and Thomas Blunier has been published in Science magazine. Brook is an assistant professor of geology and environmental science at WSU Vancouver, and Blunier is a visiting research fellow in the department of geosciences at Princeton University.

The article discusses the correlative relationship, or "bi-polar see saw," between climate change in Antarctica and Greenland. Examining ice core samples and methane gas measurements, Brook and Blunier show that when Antarctica temperatures decreased, temperatures in Greenland generally increased, and when temperatures in Antarctica increased, temperatures in Greenland decreased. The research precisely compares the timing of rapid shifts in climate over the past 100,000 years in Greenland and Antarctica, showing that rapid warming in the Northern Hemisphere coincided with rapid cooling in the Southern Hemisphere.

global change research
Concentrations of Nitrous Oxide in the Central High Plains Aquifer Are Increasing
Nitrous oxide is an important atmospheric trace gas that contributes to the greenhouse effect and the destruction of ozone. Researchers hypothesize that one important source of atmospheric nitrous oxide is ground water, yet few studies have tested this hypothesis. Concentrations of nitrous oxide in ground water from the central High Plains aquifer, in parts of Colorado, Kansas, New Mexico, Oklahoma, and Texas, are increasing, according to a recently released report, "Occurrence of Nitrous Oxide in the Central High Plains Aquifer, 1999." Well pumping for irrigation, public supply, and domestic uses is the primary mechanism for ground-water discharge from the aquifer, and pumping is one mechanism for transferring nitrous oxide from the aquifer to the atmosphere.

"The average concentration of nitrous oxide in water that recharged the aquifer since the 1950's is about twice as large as the average nitrous oxide concentration in water that recharged the aquifer prior to the 1950's," said Peter McMahon, U.S. Geological Survey hydrologist and lead author of the report. Eighty percent of the water samples collected for the study contained nitrous oxide above background concentrations. The ground water most enriched in nitrous oxide occurs near the water table, whereas deep water from the aquifer is relatively old and contains less nitrous oxide. Despite the increase in nitrous oxide concentrations in the central High Plains aquifer, the aquifer is not thought to be a significant source of atmospheric nitrous oxide at this time because most pumping wells in the study area remove the deeper water that is not enriched in nitrous oxide.

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