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
Abstract:
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.