Multi-Sensor Data Fusion for Hi-Resolution QPE Products over the CONUS

As part of NASA's effort to evaluate satellite precipitation estimates, a very high-resolution (instantaneous, 1 km) gauge-adjusted radar product has been developed. The product, which covers the entire CONUS, is expected to provide a breakthrough in the accuracy of large-scale high-resolution surface reference data available for various hydrological applications, and for verification of satellite snapshot observations. The product is based on adjusting the NEXRAD based-NMQ/Q2 radar-only precipitation rate estimates to the gauges. Pixel-by-pixel adjustment factors are calculated and applied to the radar-only estimates to generate instantaneous gauge-adjusted rain-rate mosaic.

We will describe the data fusion process, and present comparisons of the new product with

1. Q2 radar-only estimates

2. TRMM Precipitation Radar (PR) estimates during extreme precipitation events and over blockage regions

3. Satellite PMW (imager and sounder) observations.

We find that upon adjusting the Q2 products to rain gauges, the rain amount more closely agrees with that of the PR. Additional improvement is expected upon integrating the PR data into this new product.

This effort is sponsored by NASA as part of a study for evaluating satellite precipitation estimates. NMQ/Q2 data are provided by NOAA/NSSL.