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Investigators are currently measuring elemental gaseous mercury resulting from long range transport, and reactive gas mercury which is produced locally. Models have been developed for both elemental gaseous mercury surface concentrations and the reactive gaseous mercury species concentrations found to be functions of UVB input and mixing turbulence. Reactive gaseous mercury concentrations measured in springtime are the highest concentrations ever measured anywhere on the globe. Nighttime concentrations approach zero; daytime concentrations may be as high as 900 pg/m3. A manuscript is being submitted to Science.
High levels of ultraviolet (UV-B) radiation (280 to 320 nm wavelength) have been shown to be responsible for biologically harmful effects in both plants and animals. Atmospheric gases and suspended particulate matter (aerosols) absorb UV-B, the most important of which is stratospheric ozone. Because ozone in the stratosphere absorbs energy in the UV-B portion of the solar spectrum, any changes in the total amount of ozone affects the levels of UV-B reaching the ground. The potential for excessive stratospheric ozone loss in the Arctic makes the monitoring of actual variations in the billogically sensitive regions of the UV spectrum particularly important, especially since the Arctic supports a significant human population. In 1997 and 1998, with support from a new NOAA Arctic Research Initiative, NOAA deployed portable, ground-based UV instruments at three sites in Alaska: the CMDL Observatory in Barrow and the National Weather Service facilities in Nome and on St. Paul Island. Over the past decade, there has been a significant downward trend in Arctic ozone levels. Current predictions for future Arctic ozone levels indicate continued depletion for at least ten years and a very slow and possibly incomplete recovery. The observed changes in ozone in the Arctic have been accompanied by increased UV radiation, primarily in the spring. The potential for continued stratospheric ozone loss in the Arctic makes the monitoring of biologically damaging UV particularly important, since the Arctic is home to a human population and supports a variety of aquatic and terrestrial species.
Climate change studies
Research at the DoD’s U.S. Army Research Office (ARO) Activities Supported by Base Funds in FY2000 In FY2000, ARO has continued to sponsor extramural basic research directed towards the physics, mechanics, and dynamics of snow, ice, and frozen ground. This program does not support environmental change research directly, however many of the research results are applicable to a program like SEARCH. During FY00, SEARCH-related research efforts focus on: - Scale effects on the mechanical properties of fresh and saline ice, including compression and adhesion - Improving the fundamental understanding of subsurface flow, transport, and fate of contaminants in cold environments Outlook to FY2001 ARO will continue to support basic research that improves the understanding of snow, ice, and frozen ground properties and processes.
To understand and model the processes by which Arctic deep water is formed on continental shelves by the modification of inflowing Atlantic and Pacific waters.
To develop the next-generation Navy operational ice thickness and movement model.
Research at the DoD’s U.S. Army Corp of Engineers Engineering Research and Development Center - Cold Regions Research and Engineering Laboratory (CRREL) Activities Supported by Base Funds in FY2000 In FY2000, CRREL has continued to receive direct funds for a basic and applied engineering research program designed to improve both military and civilian operations affected by cold weather. This program does not support environmental change research directly, however many of the research results are applicable to a program like SEARCH. Further, understanding that the effects of climate change may be especially pronounced in colder regions, a common thread in CRREL’s diverse research program is a consideration of the impact of climate variability on the results of an investigation. CRREL FY00 SEACRH-related research efforts include: - Environmental quality: site characterization, cleanup, and prevention - Physical, mechanical, and electromagnetic properties of snow, ice, and frozen ground - Atmospheric boundary layer processes - Impact of ice covers in port and harbors - Permafrost degradation Outlook to FY2001 CRREL will continue its cold regions basic and applied research program. Basic research will continue to focus on improving the understanding of snow, ice, and frozen ground properties and energy exchange processes. Likewise, the applied research will look towards initiating the transition of this knowledge base into products that can be used to meet the Army objectives. A primary area of interest will be in supporting the development of combat systems that are light weight, rapidly deployed, and environmentally robust.
Archive of all ARCSS funded research data. ARCSS funding originates at the National Science Foundation (NSF).
Maintain oceanographic moorings in the Bering Strait to monitor heat and mass flux into the Arctic Ocean; moorings will be augmented by nutrient samplers in 2001.
To regularly deploy buoys in the Arctic to measure atmospheric temperature and pressure at various drifting sites.
The Program for Arctic Regional Climate Assessment (PARCA) was formally initiated in 1995 by combining into one coordinated program various investigations associated with efforts, started in 1991, to assess whether airborne laser altimetry could be applied to measure ice-sheet thickness changes. It has the prime goal of measuring and understanding the mass balance of the Greenland ice sheet, with a view to assessing its present and possible future impact on sea level. It includes: · Airborne laser-altimetry surveys along precise repeat tracks across all major ice drainage basins, in order to measure changes in ice-surface elevation. · Ice thickness measurements along the same flight lines. · Shallow ice cores at many locations to infer snow-accumulation rates and their spatial and interannual variability, recent climate history, and atmospheric chemistry. · Estimating snow-accumulation rates from atmospheric model diagnosis of precipitation rates from winds and moisture amounts given by European Centre for Medium-Range Weather Forecasts (ECMWF) operational analyses. · Surface-based measurements of ice motion at 30-km intervals approximately along the 2000-m contour completely around the ice sheet, in order to calculate total ice discharge for comparison with total snow accumulation, and thus to infer the mass balance of most of the ice sheet. · Local measurements of ice thickness changes in shallow drill holes ("dh/dt" sites in Figure 1). · Investigations of individual glaciers and ice streams responsible for much of the outflow from the ice sheet. · Monitoring of surface characteristics of the ice sheet using satellite radar altimetry, Synthetic Aperture Radar (SAR), passive-microwave, scatterometer and visible and infrared data. · Investigations of surface energy balance and factors affecting snow accumulation and surface ablation. · Continuous monitoring of crustal motion using global positioning system (GPS) receivers at coastal sites.
To derive sea ice motion and estimate ice thickness using RADARSAT SAR imagery.
This research consists of eight projects. 1. Climate-related remote sensing of clouds. A project to extend and test innovative techniques for observing cloud microphysical properites from ground-based cloud radar, lidar, and radiometers (P.I. Brooks Martner +1-303-497-6375) 2. Ground-based and remote sensing of microphysical and radiative properties of Arctic clouds. This project involves data analysis of radar, lidar, and radiometer data from the FIRE-III Arctic Cloud Experiment, including in situ validation with aircraft, and development of retrieval techniques of cloud microphysical properties from satellite data. (P.I. Taneil Uttal, +1-303-497-6409) 3. Deployment of surface based, active remote sensors during SHEBA. Data collected in 1997-1998 will be analyzed to provide information on cloud boundaries, radar reflectivities, radar Doppler velocities, lidar depolarization ratios, and lidar backscatter. (P.I. Taneil Uttal, +1-303-497-6409) 4. Validation of CERES cloud retrievals over the Arctic with surface-based millimeter-wave radar. The goal is to provide long-term data sets to validate satellite data from the CERES package on the TERRA satellite. (P.I. Taneil Uttal, +1-303-497-6409) 5. Development of an integrated sounding system in support of the DOE/ARM program. Microwave and millimeter wave radar data sets are being collected to study water vapor and Arctic clouds under Arctic winter conditions. (P.I. Ed Westwater, +1-303-497-6527) 6. Application of Kalman filtering to derive water vapor profiles from combined ground-based sensors. The goal is to improve calibration methods for the ARM microwave radiometers. (P.I. Ed Westwater, +1-303-497-6527) 7. Meltpond 2000. The goal is to use aircraft-based radiometers to obtain the first high spatial resolution microwave images of polynas to improve the interpretation of SSM/I and SSMIS imagery of Arctic ice. (P.I. Al Gasiewski, +1-303-497-3577) 8. Arctic atmospheric radiation studies. This collaboration with the Japanese Communications Research Laboratory provides for ground-based measurement of ozone, water vapor and cloud radiation. (P.I. Joe Shaw, +1-303-497-6496)
Objectives: 1. Locate and assemble scientific data from the U.S. Arctic on the concentrations and effects of POPs in all compartments (e.g., marine and terrestrial biota, abiotic substrates) of the Arctic. 2. Evaluate, analyze and summarize these scientific data from the U.S. Arctic into text suitable for inclusion in a new (second) AMAP publication on POPs. 3. Disseminate the summarized information via a U.S. AMAP Internet page that is directly linked to the current International AMAP Internet page. Summary (Abstract): The Arctic Monitoring and Assessment Programme (AMAP) was established in 1991 and given the responsibility of monitoring the concentrations and assessing the effects of selected anthropogenic pollutants in all compartments of the Arctic. The first AMAP assessment report, published in 1998, points out gaps in our current understanding of contaminant inputs, their transport processes and food web interactions. In addition, the AMAP report noted a serious lack of information about persistent organic pollutants (POPs) in the U.S. and Russian Arctic. Thus, the recommendations of the first AMAP report were to: monitor spatial distribution, contaminant levels and biological effects of POPs; improve the understanding of the adverse effects of POPs on human populations; and fill existing data gaps, specifically in the U.S. and Russia. In this work, we plan to identify sources of scientific information (e.g., published reports, datasets) on POPs in the U.S. Arctic and obtain these data for AMAP. Once data sources are identified, a small group of scientific experts will be assembled for a workshop to determine if any pertinent sources have been overlooked and to give advice on how best to evaluate, analyze, summarize and disseminate the information obtained. A working database will be designed so that the data and scientifically important findings or conclusions from each study can be organized and evaluated. Data will be analyzed statistically, as appropriate, to determine spatial and temporal trends. The data and scientific findings that have been collected and analyzed will then be summarized into text, for inclusion in the next AMAP publication on POPs. This major effort of synthesizing the existing data from the U.S. Arctic will ensure that the AMAP report adequately presents the accomplishments of U.S. scientists and research programs. The written publication and the summarized U.S. POPs data will also be presented as a U.S. AMAP Internet page linked to the International AMAP Internet page.
The North Slope of Alaska/Adjacent Arctic Ocean Cloud and Radiation Testbed (CART) site is providing data about cloud and radiative processes at high latitudes. These data are being used to refine models and parameterizations as they relate to the Arctic. The NSA/AAO site is centered at Barrow and extends to the south (to the vicinity of Atqasuk), west (to the vicinity of Wainwright), and east (perhaps to Oliktok). The Adjacent Arctic Ocean was probed by the Surface Heat Budget of the Arctic (SHEBA) experiment, a multi-agency program led by the National Science Foundation and the Office of Naval Research. SHEBA involved the deployment of an instrumented ice camp within the perennial Arctic Ocean ice pack that began in October 1997 and lasted for 12 monthsB. For the planning period covered here, a major focus will be on completing the facilities at Atqasuk, 100 km inland from Barrow. Presently, the instrumentation shelters are located on a gravel pad turn-around at the end of a dead end road between the town of Atqasuk and its airport. To comply with the terms of our land lease, we will construct a platform on pilings adjacent to the gravel pad and move the shelters off the roadway and onto the platform. The platform will permit long-term deployment of the Atqasuk instrumentation in a manner very similar to that at Barrow. Sky radiation (SKYRAD) radiometric instrumentation will be mounted above the level of the roof of the shelters so as to avoid shadowing, and the ground radiation (GNDRAD) instrumentation will be mounted on a tip tower such as the one about to be installed at Barrow. At Atqasuk, during the CY 2000 melt season, the science team heat flux study begun during the CY 1999 melt season will resume in spring with the redeployment of a laser scintillometer. In addition, heat flux measurements will begin near Barrow on the shore of the Beaufort Sea in the same time frame. Also at Barrow, a mini-IOP is planned during spring 2000 that will bring together two extended-range atmospheric emitted radiance interferometers (ER-AERIs) (including the one permanently installed at Barrow), one normal range downward-looking AERI (for snow characterization), and one or two other extended-range upward-looking Fourier transform infrared spectrometers (FTIRs). Various other less major enhancements will be made to the instrumentation suites of both Barrow and Atqasuk. Both facilities, however, will continue to be strongly focused on Instantaneous Radiative Flux (IRF) experiments for this planning period. A Single-Column Model (SCM) experiment utilizing either subscale or full scale aircraft that had been proposed for the NSA/AAO for CY2000 will be put off for a year.
Our objective is to monitor and understand decadal variability in the Arctic and adjacent seas. Emphasis is on the Arctic Oscillation and it impact on the western Arctic. Methods include retrospective analysis of surface and upper air, station, satellite and gridded data. We maintain a weather station at the north pole jointly with the U Washington/NSF project.
Caribou (Rangifer tarandus) were sampled (1995-96) from a mortality event near the Project Chariot site (NW Alaska), the location of a radiotracer experiment in the 1960’s, and reference sites. Radionuclide levels in muscle and bone and the cause(s) of the mortality were determined due to concerns of local residents. Bone gross alpha mean activity (n = 65) was 130.0 Bq/kg, and varied significantly (< 0.01) from 73.3 to 168.0 Bq/kg among locations. Bone and muscle gross beta mean activity was 510.4 and 9.78 Bq/kg. Bone strontium-90 mean activity (n = 58) was 137.8 Bq/kg. Muscle potassium-40 mean activity (n = 65) was 183.0 Bq/kg, and significantly varied from 76.0 to 104.4 Bq/kg by location. Muscle cesium-137 mean activity (n = 65) was 6.67 Bq/kg, ranged significantly from 0.74 to 15.6 Bq/kg by location, and increased with increasing body condition score. Bone potassium-40 mean activity ranged from 18.9 to 47.4 Bq/kg, and muscle strontium-90 ranged from 8.89 to 20.0 Bq/kg. Radionuclide concentrations were at expected levels and low in some cases as compared to Canadian caribou studies.
Develop conceptual models of biocomplexity for the Bering Sea watershed to describe and predict the combined effects of multiple stressors on key components of the Bering Sea ecosystem.
The following information about CLIC was taken from "Initiative", from the Climate and Cryosphere (CLIC) -- A New WCRP Initiative web site ( http://www.npolar.no/acsys/CLIC/clicindex.htm) The web site features an Acrobat PDF file version of the CLIC Draft Science and Coordination Plan (dated 8 April 2000)that should be referred to for latest information. CLIC - a new initiative for WCRP Howard Cattle -- Chairman, ACSYS Scientific Steering Group At their annual meeting, held in Cape Town, South Africa from 16-20 March 1998, the Joint Scientific Committee (JSC) for the World Climate Research Programme (WCRP) reviewed the issue of the organisation of research into the Climate and Cryosphere in the WCRP. Key to this review was a paper from the ACSYS Scientific Steering Group (SSG) identifying gaps in our knowledge of some cryospheric processes in the climate system and summarising the various options for the organisation of cryospheric studies within WCRP. This paper was developed by a subgroup at the sixth ACSYS SSG meeting (November 1997), chaired by Professor Roger Barry. As a result of their review, the JSC XIX endorsed the idea of a broader programme on Climate and Cryosphere (CLIC) in the WCRP (WMO/TD-No. 929, 1998). As a first step, a Task Group was established to develop a science and coordination plan for CLIC for presentation at the twenty-first session of the JSC in March 2000, when the decision will be made on whether to initiate CLIC as a full WCRP project. More detail on the background to this can be found in an article by Hartmut Grassl and Victor Savtchenko "Cryosphere and Climate: organisation of the WCRP contribution" in WCRP Newsletter No. 2 and an article by Howard Cattle and Roger Barry "Cryosphere and Climate, The ACSYS Statement" in WCRP Newsletter No. 3. The key element of CLIC is that it will provide a globally integrated approach to the study of the role of the cryosphere in the climate system. The science and coordination plan to be developed will look at the requirements for initiating studies of cryospheric elements in which there are perceived gaps in present programmes that impact on global change research including sea level rise. It will also look at requirements for enhancing links between existing global and regional cryospheric studies and lay out a programme for ensuring accurate and appropriate treatments of cryospheric processes and interactions of the cryosphere with atmosphere, oceans and land surface in climate models and for assembling the global and regional cryospheric datasets necessary for driving and validating climate models and for diagnostic studies of the role of cryosphere in climate. Important from the coordination point of view is to provide suggestions for mechanisms for interactions with other WCRP projects, in particular GEWEX and CLIVAR, and with other cryospheric projects that could contribute to WCRP research, including identification of suitable links and mechanisms for collaboration. In summary, CLIC aims to have the following primary missions and activities: 1.Coordinates the cryospheric elements of existing projects of the WCRP (especially ACSYS, GEWEX, CLIVAR) with the aim of identifying gaps in WCRP global cryospheric research within, and at the interfaces between, these projects. 2.Coordinates, sponsors, and encourages cryosphere projects conducted under other organisations (e.g., SCAR in the southern hemisphere, IASC in the northern hemisphere) to ensure appropriate broadening of these activities and that these serve WCRP needs related to the study of cryosphere and climate. 3.Acts as the "friendly broker" between programmes and projects (both internal and external to WCRP) that are conducted in the cryosphere with some common aims, such as CLIVAR-ACSYS, ACSYS-GEWEX, ASPeCT-WCRP and MAGICS-WCRP (among others). 4.Establishes projects in the study of the role of the cryosphere in climate that cover identified gaps; these projects may involve joint sponsorship by the appropriate governmental and non-governmental bodies. The CLIC Task Group, which is responsible to the JSC through the ACSYS SSG, had its first meeting in Utrecht, The Netherlands, from 8-11 July 1998. Its co-chairs are Professor Roger Barry (NSIDC/CIRES, University of Colorado, email@example.com) and Dr. Ian Allison (Antarctic CRC, University of Tasmania, firstname.lastname@example.org). The meeting was hosted by the Institute for Marine and Atmospheric Research of Utrecht University. Attendees were Roger Barry, who chaired the meeting , Steve Ackley, Oleg Anisimov, Howard Cattle, Eberhard Fahrbach, Barry Goodison, Moto Ikeda, Peter Lemke, Doug Martinson, Liz Morris, Hans Oerlemans, Olav Orheim and, from WCRP, Hartmut Grassl and Victor Savtchenko. The main business was to initiate the drafting of the CLIC Science and Coordination Plan, a first version of which was discussed by the ACSYS SSG when it met in Tokyo, Japan, in November 1998. The Plan was modified to take into account the SSG’s comments. It will be presented in initial draft form to the JSC for WCRP when they meet in Kiel, Germany, in March 1999. The draft is now available as a pdf file on the ACSYS CLIC web page. http://www.npolar.no/acsys/CLIC/clic_draft.PDF. Comments on the draft from the community are welcomed. Reference: WMO/TD-No. 929, 1998: Annual review of the World Climate Research Programme and report of nineteenth session of the Joint Scientific Committee (Cape Town, S. Africa, 16-20 March 1998).