MRMS Hourly Rainfall Estimates Compared to Dual Polarization Hourly Rainfall Estimates in the Year 2020 in the Greater Puget Sound Region of Washington State
Authors
Murphy, Nathaniel
Date
2024-05
Type
Thesis
Language
en
Keywords
Alternative Title
Abstract
ABSTRACT
MRMS HOURLY RAINFALL ESTIMATES COMPARED TO DUAL POLARIZATION HOURLY RAINFALL ESTIMATES IN THE YEAR 2020 IN THE GREATER PUGET SOUND REGION OF WASHINGTON STATE
By Nate Murphy
Plymouth State University, December, 2024
The purpose of this research is to compare precipitation estimates between
radar-only MRMS and dual-polarization WSR-88D for moderate to heavy rainfall in the greater Puget Sound region of Washington State throughout the year of 2020. The dual polarization radar and MRMS radar-only estimates are compared to the rain gauge measurements to see if any product performed better than the other. Rainfall estimates from MRMS, Takoma Washington Doppler Radar (KATX), and Langley Hill Doppler Radar (KLGX) are compared to observations from seven rain gauge locations. Both the MRMS radar-only QPE and the dual polarization estimates underestimated rainfall rates. However the bias was slightly less for the MRMS radar-only QPE. There was no significant correlation between any set of data when not split up by rain gauge location. When split up by rain gauge location, different products performed better and had significantly higher correlations. Also it was found that the MRMS radar-only QPE estimate had a slightly lower RMSE when compared with the dual polarization estimates. Some possible explanations for the under estimating in the area could be potential beam blockage in the region due to the mountainous terrain in the area.