Mapping Mesoscale Pressure Fields Using D-Value Measurements from the NSF/NCAR Gulfstream V Research Aircraft

Pressure measurements from the NSF/NCAR Gulfstream V research aircraft have recently been calibrated in flight through use of a new laser air motion sensing system. D-values can be calculated from the difference between the actual altitude, provided by modern Global Positioning System receivers, and the pressure altitude based on these improved measurements of pressure. The result is that the height of constant-pressure surfaces can be mapped with an uncertainty approaching 1 m . This enables the mapping of mesoscale pressure fields using appropriate flight patterns.

Maps obtained from some recent flights will be shown and compared to synoptic-scale maps of the surrounding areas as well as maps obtained from dropsondes deployed from the aircraft. Autocorrelation distances and times for the D-value measurements and for associated soundings show important error characteristics and measures of the representativeness of such measurements. Uncertainty analyses will show that, with the range and high speed of the GV, these measurements provide important opportunities for mapping mesoscale pressure fields from this aircraft.