How does the NOAA/National Centers for Environmental Prediction (NCEP) quality control upper-air data?
Before ingesting rawinsonde data into numerical weather prediction models, NCEP corrects temperature data (for some radiosonde types such as Sippican) for solar and infra-red radiation and checks the quality of the data using objective and subjective techniques. Solar and infra-red radiation significantly affects the accuracy of radiosonde temperature data at heights over 15 km. The temperature errors caused by radiation can exceed 1OC. These errors are difficult for upper-air observers to detect and they are not expected to correct the data. Full correction of the errors is difficult, but NCEP applies an adjustment to the temperature data to reduce the error. For checking data quality, NCEP utilizes computerized comparisons of the actual upper-air data received from an upper-air station with that generated from a 6-hour numerical weather prediction model. These automated data quality control programs are then combined with knowledge of how the real atmosphere operates. NCEP meteorolog
