A - C
ATMOSPHERIC TELECONNECTIONS AND
The Arctic will experience some of the more dramatic environmental changes in the 21st century as surface air temperatures continue to rise in response to anthropogenic forcing. This will lead to an intensification of the Arctic hydrologic cycle. At regional scales, however, it remains unknown how precipitation, evaporation, and river discharge are evolving in a warmer world. This study will investigate the role of large-scale atmospheric anomalies in the Canadian northern hydrologic cycle with a focus on the IPY. Specifically, we will address the following science questions: 1) What are the dominant large-scale atmospheric teleconnections that affect northern Canada? 2) What is the role of these teleconnections and their relative contributions to the atmospheric and surface water budgets of high-latitude river basins in a changing environment? 3) How will the meteorological and hydrological variables differ from their mean state during the IPY and how will they evolve in the near future? To answer these important science questions, the following work will be conducted according to the proposed timeline: -2006-2007: Historical meteorological and hydrological data will be analysed. Relationships between atmospheric teleconnections such as the Arctic Oscillation (AO), El Niño/Southern Oscillation (ENSO), and the Pacific Decadal Oscillation (PDO) and the state of the hydrologic budget over northern Canada will be evaluated. The European Centre for Medium-Range Weather Forecasts (ECMWF) Reanalysis (ERA40) data set will provide global meteorological data that will be supplemented by observed river discharge from the Canadian Hydrometric Database (HYDAT) and observed precipitation and temperature from the Climate Research Unit (CRU) of the University of East Anglia. The analysis will cover the period 1964-2004 for which spatial and temporal coverage is best and focus on the Mackenzie and Hudson Bay river basins. -2007-2008: During the IPY intensive observing period, real-time monitoring of the atmospheric teleconnection indexes and of the hydrologic budget in northern Canada will be maintained. The daily and recent state of atmospheric and hydrologic variables, including daily assessments of their deviations from the mean, will be reported on our website to provide other researchers this valuable information. -2008-2009: A diagnostic study of the atmospheric and hydrologic state over northern Canada during the IPY will be conducted. This work will focus on the anomalies during the IPY from the mean state (1964-2004). An assessment of trends in the atmospheric teleconnection indexes and in the hydrometeorological variables will provide insights on the possible future state of northern Canada’s hydrologic cycle. Summary provided by http://classic.ipy.org/development/eoi/proposal-details-print.php?id=159