This project will develop an Arctic System Reanalysis (ASR). The ASR, which can be viewed as a blend of modeling and observations, will provide a high resolution description in space (20 km) and time (3 h) of the atmosphere-sea ice-land surface system of the Arctic. The ASR will ingest historical data streams along with measurements of the physical components of the Arctic Observing Network being developed as part of the IPY. Gridded fields from the ASR, such as temperature, radiation and winds, will also serve as drivers for coupled ice-ocean, land surface and other models, and will offer a focal point for coordinated model inter-comparison efforts. The ASR will permit reconstructions of the Arctic system's state, thereby serving as a state-of-the-art synthesis tool for assessing Arctic climate variability and monitoring Arctic change. The ASR will also shape the legacy observing network of the IPY by providing a vehicle for observing system sensitivity studies. The first generation ASR as outlined here will span the years 2000-2010.
