The impact of additional aircraft data on the Goddard Earth Observing System analyses

The impact of utilizing additional densely spaced aircraft observations on the Goddard Earth Observing System Data Assimilation System wind analyses is investigated. The additional data, the Global Aircraft Data Set (GADS), comes from flight data recordings of 30 British Airways Boeing 747-400 aircraft that are not used in operational analyses. The GADS experiment was created to provide data needed to improve analyses of strong winds near jet streams. All major operational centers underestimate such winds. The impact of including the GADS observations in the analyses is investigated using some cases from the 1995 Northern Hemisphere winter. The additional aircraft observations produce a substantial impact on the Goddard wind speed analyses in both sparse aircraft data regions (North Africa, Middle East, South America) and dense aircraft data regions (west Atlantic, east Asia, North America). Examples of the space and time extent of the impact are presented.