New estimates of atmospheric moisture balance quantities in the Arctic are computed by coupling daily satellite-derived water vapor and temperature profiles with NCEP Reanalysis wind fields for the years 1985-1994. Moisture fields from the TIROS Operational Vertical Sounder (TOVS) are temporally interpolated to six-hourly intervals and used in a finite differencing advection scheme with six-hourly winds at 100 km resolution. This procedure yields daily moisture flux convergence and vapor flux vector fields over the entire Arctic region north of 60 degrees. This data set is unique because it provides daily coverage over the entire Arctic region and is free of model biases evident in reanalysis moisture fields.
I estimate daily evaporation using TOVS retrievals of atmospheric boundary layer stratification, low-level moisture, and surface characteristics, along with NCEP surface pressure analyses. By adding evaporation to the vapor flux convergence fields, seasonal and yearly precipitation estimates are generated. Comparisons of these ten-year climatologies to existing in situ Arctic data sets show broad similarities. Additionally, the finer spatial structure of satellite-derived fields reveal some previously unobserved interactions between the atmosphere, land, and sea-ice cover. In this poster, I will discuss the methodology for calculating the moisture balance quantities and describe the new climatological fields and their dominant features.
The satellite data used in the study are contained in the NASA/NOAA TOVS Polar Pathfinder data set. When completed in late 1998, the TOVS Path-P data set will extend from 1978 through 1996, allowing this study to be expanded to 18 years. Please see my other presentation entitled: Temporal Variability of Arctic Atmospheric Moisture Budget Quantities Derived from 10 Years of TOVS Satellite Moisture Retrievals and NCEP Reanalysis Winds