Detection and correction of temperature inhomogeneities in the radiosonde data

The National Climatic Data Center (NCDC/WDCA) of the United States of America and the All-Union Research Institute of HydroMeteorological Information (AURIHMI/WDCB) have worked together to produce an upper-air dataset called the "Comprehensive Aerological Reference Data Set" (CARDS.

The goal of the CARDS project was to produce an upper-air data set of radiosonde observations suitable for use in evaluating climate models and detecting climate change. To achieve these goals it was necessary to collect upper-air data from various sources, to develop station histories, and to develop a quality control(QC) program.

As of June 1999, the CARDS database consist of approximately 25 million observations from 1948 to December 1998. The data have been processed by the horizontal-synoptic complex quality control system. Later this year the CARDS database will be processed by the time series checking quality control system.

A sounding in the CARDS database consists of the "raw" data in the form the data were received(no corrections applied by CARDS) and quality controlled (QC) data. When corrections are made in a level in the sounding, a new level is produced in the sounding.

A station history was developed from the data and various records in the US, Russia, and the WMO. An instrument station history was developed by Dian Gaffen of ARL/NOAA.

A climate core dataset has also been developed and consists of approximately 230 stations.

CARDS data can be ordered from the National Climatic Data Center, Asheville.