A NEW GLOBAL GRIDDED RADIOSONDE TEMPERATURE DATA-BASE AND RECENT TEMPERATURE TRENDS

We present a new analysis of global radiosonde temperature data. From 1979 onwards, the data from the Australasian region have been correcte d for instrument-related discontinuities with the help of comparisons with collocated retrievals from satellite-based Microwave Sounding Uni ts (MSU) and metadata: in future work, adjustments will be applied wor ldwide and extended to earlier years. The data are stored as monthly a nomalies from a 1971-1990 reference period on a 5 degrees latitude x 1 0 degrees longitude grid at 8 levels from 50 hPa to 850 hPa. Seasonal and annual temperature anomalies have also been created on a 10 degree s x 20 degrees grid using an eigenvector reconstruction method to filt er noise. Latitude-height profiles of zonal-mean temperature changes s ince the 1960s show significant cooling in the lower stratosphere, esp ecially in middle and high latitudes of the Southern Hemisphere, but t he cooling over Australasia is less than shown by unadjusted data. War ming dominates the troposphere but is not a maximum in the tropical up per troposphere. In the annual mean, tropospheric warming is greatest around 45 degrees N and possibly in the data-sparse high latitudes of the Southern Hemisphere.