Assessing the Impact of Mesonets

The National Academy of Science (2009) report “Observing Weather and Climate from the Ground Up” emphasized developing an architecture to integrate existing and future networks into a national network of networks. A necessary step for developing such an integrated network is to assess the impact of existing mesonets. The adjoint of a two-dimensional variational analysis system of surface weather parameters covering the entire continental United States has been developed to assess objectively the sensitivity of the resulting analyses to the source of the observations used in the analysis. The analysis system uses the 5 km resolution background fields used by the Real Time Mesoscale Analysis (RTMA) developed by the National Centers for Environmental Prediction. Roughly 12000 observations available each hour from many different mesonets are then used to modify the background grids and obtain hourly analyses. The sensitivity of the differences in weather parameters between the resulting analyses and the background fields are examined as a function of the various data assets, e.g., FAA/NWS stations; Remote Automated Weather Stations (RAWS), and stations installed and maintained by federal, state, and local agencies, commercial firms, and the public. Statistics for individual stations as well as for entire networks are obtained that help to identify network characteristics that strongly influence analyses.