The Space Component of an Integrated Arctic Observing System: Past, Present, and Future

The satellite record now spans 30 years and provides an unprecedented view of recent changes in the arctic cryosphere, atmosphere, and ocean. Even though the operational satellites of the 1980s and 1990s were not designed for climate monitoring, we have learned much about recent arctic climate after carefully calibrating and reprocessing these data. In response to the need for more detailed, quantitative information on the Earth-atmosphere system, satellite infrastructure has matured considerably over the last decade. Experimental satellite sensors have proven their worth for monitoring ice and atmospheric properties. Synthetic aperture radars, hyperspectral infrared sounders, and cloud radars and lidars are now invaluable complements to heritage visible/infrared imagers, sounders, and passive microwave radiometers. More recently, the 2007-2008 International Polar Year (IPY) stimulated the coordination of satellite acquisitions, new products, and mission planning through projects such as the Global Interagency IPY Polar Snapshot Year (GIIPSY), the Integrated Global Observing Strategy (IGOS) Cryosphere Theme, and the World Meteorological Organization's Space Task Group for IPY. Observational requirements for the Arctic and Antarctic that can best, and perhaps only, be met using the international constellation of Earth observing satellites have been defined and are shaping our picture of the ideal space-based observing system for the Arctic.