Vorosmarty, C., L. Hinzman, B. Peterson, D. Bromwich, L. Hamilton, J. Morison, V. Romanovsky, M. Sturm, and R. Webb, 2002: Arctic-CHAMP: A program to study Arctic hydrology and its role in global climate. EOS Trans. AGU, 83, 241, 244-245, 249.


INTRODUCTION

The Arctic constitutes a unique and important environment that is central to the dynamics and evolution of the Earth system. The Arctic water cycle, which controls countless physical, chemical, and biotic processes, in turn, regulate the climate, habitat, and natural resources that are of great importance to both native and industrial societies. Comprehensive understanding of water cycling across the Arctic and its linkage to global biogeophysical dynamics is a scientific as well as strategic policy imperative.

The Arctic is inherently a dynamic system with rapid shifts in state demonstrated repeatedly in the paleo record [Overpeck et al., 1997]. Yet, there is mounting evidence that it is now experiencing an unprecedented degree of environmental change - broad-scale increases in air temperature, thinning of sea ice, melting of glaciers, thawing of permafrost, and reductions in snow cover [Serreze et al., 2000; SEARCH SSC, 2001]. Periodic failure of important fish landings and its economic consequences are linked to low salinity anomalies, and thus, to changes in the freshwater cycle [Hamilton and Allanson, 2001]. There is also concern about how recently-observed increases in freshwater supply to the Arctic Ocean [e.g., Semiletov et al., 2000] could reduce thermohaline circulation, with potentially enormous global-scale consequences [Broecker, 1997]. Unfortunately, the sources and ultimate consequences of these many changes are still poorly understood.

In September 2000, a workshop supported by the National Science Foundation's Arctic System Science (NSF-ARCSS) Program was convence at the National Center for Ecological Analysis and Synthesis (NCEAS) in Santa Barbara, California. The workshop participants assessed the current state-of-the-art in Arctic systems hydrology and identified research priorities for achieving predictive understanding of feedbacks arising from changes to the Arctic water cycle. The meeting was well-represented within the Arctic research community, with more than 30 participants drawn from the disciplines of land surface hydrology, terrestrial and freshwater ecology, atmospheric dynamics, oceanography, socioeconomics, simulation modeling, remote sensing, and geo-spatial analysis.

A drafting committee captured the deliberations and reported its findings in a peer-reviewed strategy document [Vorosmarty et al., 2001] that highlights the scientific, technical, and institutional challenges that separate us from a clear understanding of Arctic hydrological change. It also presents a plan for new synthesis research to clarify the importance of Arctic fresh water within the Earth system and in global change. This article provides a brief overview of key elements in the report and discusses its call for the creation of a major new research program at NSF - Arctic-CHAMP, the pan-Arctic Community-wide Hydrological Analysis and Monitoring Program.