On December 18, 1999, the Terra satellite was launched with a complement of five instruments including the Moderate Resolution Imaging Spectroradiometer (MODIS). Many geophysical products are derived from MODIS data including global snow-cover products. MODIS snow and ice products have been available through the National Snow and Ice Data Center (NSIDC) Distributed Active Archive Center (DAAC) since September 13, 2000. MODIS snow-cover products represent potential improvement to or enhancement of the currently available operational products mainly because the MODIS products are global and 500-m resolution, and have the capability to separate most snow and clouds. The MODIS snow-mapping algorithms are automated, which means that a consistent data set may be generated for longterm climate studies that require snow-cover information. Extensive quality assurance (QA) information is stored with the products. The MODIS snow product suite begins with a 500-m resolution, 2330-km swath snow-cover map, which is then gridded to an integerized sinusoidal grid to produce daily and 8-day composite tile products. The sequence proceeds to a climate-modeling grid (CMG) product at 0.05j resolution, with both daily and 8-day composite products. Each pixel of the daily CMG contains fraction of snow cover from 40% to 100%. Measured errors of commission in the CMG are low, for example, on the continent of Australia in the spring, they vary from 0.02% to 0.10%. Near-term enhancements include daily snow albedo and fractional snow cover. A case study from March 6, 2000, involving MODIS data and field and aircraft measurements, is presented to show some early validation work. D

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Valley and mountain glaciers and ice caps respond to changes in regional climate on the scale of decades; thus, they can serve as indicators of regional climate change. During the last century, most valley and mountain glaciers and ice caps receded [Meier, 1984; Haeberli et al., 1989], although some advances have occurred during periods of cooling [Wood, 1988]. Glaciers in Iceland [Rist, 1975] and in the eastern Alps of Austria [Patzelt, 1980] have followed a similar pattern. Images acquired by satellite sensors can provide a regional overview for studying changes in glacier area, terminus position, glacier facies [Williams et al., 1991], and the position of the regional snow line, while insitu studies usually provide measurements at only a single point. Major changes in glaciers may be obvious from initial inspection of satellite images; however, detailed study of digital image data can reveal the presence of small changes that are useful indicators of regional trends in glacier mass balance. If observed over a long enough period of time in many different geographic settings, glacier‐terminus position changes can be related to changes in regional and even global climate.

What were the indigenous agricultural and population patterns in peninsular Malaysia's southern lowlands? What factors produced these patterns? Based on our analysis of ethnographic and historical evidence, as well as aerial photographs taken in 1948 in the Tasek Bera and Sungai Bera watersheds, the Semelai, an Orang Asli group, had a robust and productive subsistence agricultural system emphasising rice but insured by cassava. These photographs, from the P.D.R. Williams-Hunt Collection, provide an unusual record of Semelai agriculture prior to settlement in 1954 and contribute to our knowledge of indigenous economic patterns in the southern lowlands, which have received little ethnographic attention.