Status report on the key climate variables technical supplement to the
Significant data management issues
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Significant data management issuesData access. Many existing data are not accessible, either within country or internationally. Resolution of this barrier requires: promoting political commitment to data sharing; removing practical barriers by enhancing electronic interconnectivity and metadata; and data rescue and digitization. Networks. Most networks are severely contracting in Russia and Canada. Station automation is also cutting back, or changing the nature of, the snow depth measurement at GTS stations. No good documentation of where and when these changes have occurred is readily available. Verification of satellite products. Substantial ongoing research and surface observation is needed to calibrate and verify algorithms and products. Analysis productsSnow cover extent: (i) daily NH-extent map since May 1999, and gridded data (1024 by 1024 box grid, ca. 25 km), monthly statistics (frequency, anomaly ) for NH, N-America and Asia. [Weekly data for 1966-1999]. Interactive Multisensor Snow and Ice Mapping System (IMS) Daily Northern Hemisphere Snow & Ice Analysis: http://orbit-net.nesdis.noaa.gov/crad/sat/surf/snow/HTML/snow.htm. (ii) The Northern Hemisphere (Equal Area Scalable Earth (EASE) Grid Weekly Snow Cover and Sea Ice Extent product combines snow cover and sea ice extent at weekly intervals for October 1978 through June 2001, and snow cover alone for October 1966 through October 1978 (sea ice data were not available prior to October 23, 1978). The data set is the first representation of combined snow and sea ice measurements derived from satellite observations for the period of record. Data are provided in a 25 km equal area grid (NSIDC EASE- Grid): http://nsidc.org/data/nsidc-0046.html. (iii) Moderate Resolution Imaging Spectroradiometer (MODIS) products include level 2 swath data (MOD10_L2) at 500 m resolution, level 3 gridded daily and 8-day composites (MOD10A1 and MOD10A2, respectively) at 500 m resolution, and level 3 daily and 8-day global maps on a climate modeller’s grid (MOD10C1 and MOD10C2, respectively) at 0.05 degree resolution. MODIS snow cover data are based on a snow mapping algorithm that employs a Normalized Difference Snow Index (NDSI) and other criteria tests. Data also contain local and global metadata (see http://modis-snow-ice.gsfc.nasa.gov/intro.html). Users' Guide: http://modis-snow-ice.gsfc.nasa.gov/sugkc.html. Order data from: http://nsidc.org/NASA/MODIS/ 
Monthly Northern Hemisphere snow cover (1966-2001) and sea ice extent (1978-2001) climatologies (Source: Northern Hemisphere EASE-Grid Weekly Snow Cover and Sea Ice Extent Version 2, NSIDC, University of Colorado, Boulder). Snow depth: operational global daily snow depth analysis by the Canadian Meteorological Centre http://weatheroffice.ec.gc.ca/analysis/index_e.html. National products include: (a) the Historical Soviet Daily Snow Depth Version 2 (HSDSD) product on CD-ROM, based on observations from 1881 to 1995 at 284 World Meteorological Organization (WMO) stations throughout Russia and the former Soviet Union. The area covered is 35° to 75° N latitude and 20° to 180° E longitude. The State Hydrometeorological Service in Obninsk, Russia, provided the data through the US-Russia Agreement on Co-operation in the Field of Protection of the Environment, Working Group VIII data exchange program. (Armstrong, R. 2001. Historical Soviet Daily Snow Depth Version 2 (HSDSD). Boulder, CO, USA: National Snow and Ice Data Center. CD-ROM: http://nsidc.org/data/g01092.html. (b) NOAA Experimental Daily NWS/COOP Snow Depth and Snowfall Graphics and Data - Daily snow depth (most recent day) and snowfall graphics (most recent 1, 2, 3 and 7 days) and data for the contiguous United States. (c) Daily snow depth data for 1062 observing stations across the contiguous US covering the period 1871-1997 are available from the Carbon Dioxide Information and Analysis Center (CDIAC) (Easterling et al., 1999). (d) Daily snow depth data for Canada at several 1,000 stations covering the entire period of record up to 1999 are published on CD-ROM and are freely available for research use (Meteorological Service of Canada, 2000: Canadian Snow Data CD-ROM): CRYSYS Project, Climate Processes and Earth Observation Division, Meteorological Service of Canada, Downsview, Ontario]. 
Visible-derived (NOAA) and passive microwave-derived (SMMR and SSM/I) snow-covered area departures from the monthly means (dashed lines) and 12-month smoothed (solid lines). Armstrong and Brodzik, 2001. Snow water equivalent: observed by national, state, provincial and private networks in many countries on a 10 day - monthly basis. No central archive exists and many national/other data bases are not readily accessible. No standard global SWE product exists. NSIDC (R. L. Armstrong) has developed a Northern Hemisphere mean monthly product for 1978-2000 based on SMMR and SSM/I passive microwave data. This is not yet released as a data product. The Former Soviet Union Hydrological Snow Surveys are based on observations at 1,345 sites throughout the Former Soviet Union between 1966 and 1990, and at 91 of those sites between 1991 and 1996. These observations include snow depths at World Meteorological Organization (WMO) stations and snow depth and snow water equivalent measured over a nearby snow course transect. The station snow depth measurements are a ten-day average of individual snow depth measurements. The transect snow depth data are the spatial average of 100 to 200 individual measuring points. The transect snow water equivalent is the spatial average of twenty individual measuring points (http://nsidc.org/data/g01170.html). Weekly maps of SWE from SSM/I over the Canadian prairies are available from http://www.msc.ec.gc.ca/ccrp/SNOW/snow_swe.html. Weekly snow extent and water equivalent for the western United States include anomalies and elevational extent map (http://www.nohrsc.nws.gov/html/opps/opps.htm). SNOTEL network database for the western United States compiled by Serreze et al. (1999). The data are primarily from pressure pillows that weigh the snow pack. Canadian snow course observations (~2000 sites, mostly in the period. 1950-1995) are published on the Snow CD (MSC, 2000) Canadian National Plan for Cryospheric Monitoring in Support of GCOS: Canada underwent an extensive exercise to determine a national monitoring strategy for snow, as well as the rest of the cryosphere; the workshop summaries and final report are online at: http://www.crysys.ca/science/documents/GCOS/cdn_gcos_plan_title.htm. Directory: pages -> prog prog -> Regional Association IV (North America, Central America and the Caribbean) Hurricane Operational Plan prog -> Review of the ra IV hurricane operational plan prog -> Cyclone programme prog -> World meteorological organization prog -> World meteorological organization technical document prog -> Regional Association IV (North America, Central America and the Caribbean) Hurricane Operational Plan prog -> World meteorological organization ra IV hurricane committee thirty-fourth session prog -> World meteorological organization ra IV hurricane committee thirty-third session prog -> Review of the past hurricane season prog -> Ra IV hurricane committee thirty-fourth session ponte vedra beach, fl, usa Download 0.61 Mb. Share with your friends:
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