ESRL Global Systems Division

NOAA GPS-Met Observations Improve Canadian Weather Forecasts

In a paper just submitted to the Annual Meeting of the American Meteorological Society in San Antonio, TX in January 2007, scientists from Environment Canada report that assimilation of ESRL's Global Systems Division (GSD) ground-based GPS observations into Canadian weather models improves their humidity forecasts. These findings relate to the mid-troposphere in the 0-24 hour range, and also improve precipitation forecasts out to 48 hours. The results are especially true for the summer period in the southeast United States. The work was carried out by Stephen Macpherson, Godelieve Deblonde, and Josep Aparicio of the Meteorological Research Branch in Quebec. This is significant because previous studies showed only shorter-term (0-24 hour) positive impact. Their results, however, indicate that the greatest improvements are actually for longer range (24-48 hour) precipitation accumulations.

ESRL's GPS-Met Observing System Section has made its observations and derived products available to the U.S. and international research community since 1996. In 2004, the Meteorological Research Branch of Environment Canada started to continuously ingest GPS water vapor observations provided by ESRL's GSD at the Canadian Meteorological Centre in Quebec. This NOAA collaboration with Environment Canada has allowed them to investigate the impact of GPS-Met on Canadian weather forecasts and evaluate the benefits of their establishing a GPS-Met observing system in Canada.

Through this international collaboration, GSD contributes to NOAA's mission of meeting society's diverse and expanding needs for weather-related information as well as by demonstrating how the development of new technologies and techniques improves the accuracy of weather and forecast modeling.

Contact information
Name: Seth Gutman
Tel: 303-497-7031