Comprehensive Bias-free Precipitation Archive for Northern Eurasia: What it Can Declare About Changes in the Arctic Fresh Water System?

Recently, we compiled, preprocessed, and released for the scientific community an archive of in situ daily, 6-hourly, and half-daily precipitation for the former USSR at 2188 stations for the period 1891 to 2001 (NCDC Data Set 9813). The archive was compiled within the framework of several joint projects of All-Russian Research Institute for Hydrometeorological Information-World Data Center and Main Geophysical Observatory of the Federal Service for Hydrometeorology and Environmental Monitoring, Obninsk, Russian Federation, and NOAA National Climatic Data Center, Asheville, North Carolina. Variables in the data set include (1) raw daily precipitation, (2) homogenized daily precipitation using the Groisman and Rankova, (2001, Internat. J. Climatol.) technique, (3) comprehensively corrected daily precipitation using a technique developed by Bogdanova et al (2002a,b, J. Hydrometeorol. and Russian Meteorol. and Hydrol.), and (4) raw sub-daily synoptic precipitation. Mostly Russian data are present in the archive after 1991. Comprehensive correction of precipitation measurements require information about trace precipitation, precipitation type, wind speed, air temperature, humidity, atmospheric pressure, gauge type, station exposure, snow cover, and previous day weather characteristics. Therefore, it was a laborious enterprise to implement the Bogdanova et al. algorithm. But, the ongoing debate about the causes of runoff changes to the Arctic Ocean and the needs of the climate modeling community require an urgent delivery of the input information to those who are in charge of resolving this controversy. The algorithm implementation en masse, provides new features about both climatology and variations of precipitation in the high latitudes of Northern Eurasia. They will be presented at the Meeting.