Quantifying Evaporation at Low Levels of the Atmosphere using a Vertically Pointing Radar (245)

Jon Bongard, University of Missouri, Columbia, MO

Neil Fox, University of Missouri

Sam Marlow, University of Missouri

Patrick Market, University of Missouri



Quantifying Evaporation at Low Levels of the Atmosphere using a Vertically Pointing Radar

This study examines the use of a vertically pointing radar (MRR) to quantify evaporation at various atmospheric levels. From the vertically pointing radar we observe the liquid water content (LWC) at all levels up to as high as 6,000 meters (~20,000 feet). We take the LWC flux of the overhead column of air and compare it to the reflectivity (dBZ) both at the surface and upper levels in the atmosphere measured by the MZZU dual-pol radar to quantify the amount of evaporation in the lower levels. This is then compared to rainfall evaporation estimated using the NWS KLSX radar applying the method developed by Pallardy and Fox (2018). In this procedure the drop size distribution (DSD) aloft is derived from dual-polarization parameters and the evaporation of each size of falling drop is adjusted using mesoscale model temperature and humidity layers. The resulting surface rainfall rate will be assessed with reflectivity and differential reflectivity (ZDR) data from the dual-pol MZZU radar as well as rain gauges located in the same research area as the vertically pointing radar.

This will be done for several types of rainfall to study the differences in evaporation for each in their respective environments. Types of rainfall include light rain, moderate (stratiform) rainfall, and heavy convective precipitation. Supplemental data for this research will include DSD surface data from the disdrometer established in the same location as the MRR as well as the radiosonde sounding data from that location for the various case studies.