D68    GPS ZTD IWV seasonal bias report.

Responsible partner
Due date

This is part of work-package 9400 the purpose of which is:

Determine the reason for seasonal biases in the GPS ZTD IWV products.

Methodology/Work Description

Results from the EC MAGIC project showed that the difference between GPS ZTD and radiosondes increased in magnitude in high humidity regimes, producing a seasonal signal in these differences.  These signals limit the ability to separate a climatic signal from the noise in the of GPS ZTD products.

·        Chalmers will investigate the seasonal component of long term.

Deliverable D68: The results of the work on seasonal signals in GPS ZTD and IWV are described
in the report: GPS System Reseach: Assessment of Systematic Effects in Estimated Zenith Wet Delays.
For furtther information contact Camilla Granstroem, Jan Johansson or Gunnar Elgered at Chalmers Technical Universtiy.