Title
The GPM-DPR Blind Zone Effect on Satellite-Based Radar Estimation of Precipitation over the Andes from a Ground-Based Ka-band Profiler Perspective
Date Issued
01 January 2022
Access level
metadata only access
Resource Type
journal article
Publisher(s)
American Meteorological Society
Abstract
A vertically pointing Ka-band radar (Metek MIRA-35C) installed at the Instituto Geofísico del Perú, Atmospheric Microphysics and Radiation Laboratory (LAMAR) Huancayo Observatory, which is located at an elevation of 3.3 km MSL in the Andes Mountains of Peru, is used to investigate the effects of terrain on satellite-based precipitation measurement in the Andes. We compare the vertical structure of precipitation observed by the MIRA-35C with Ka-band radar measurements from the Dual-Frequency Precipitation Radar (DPR) on board the Global Precipitation Measurement (GPM) mission core satellite using an approach based on Taylor’s hypothesis of frozen turbulence that attempts to reduce the impact of spatiotemporal offsets between these two radar measurements. From 3 April 2014 to 20 May 2018, the DPR measured precipitation near LAMAR during 15 of its 157 coincident overpasses. There were six simultaneous observations with MIRA-35C. We found that the average of the DPR’s lowest clutter-free bin is 1.62 km AGL, but the presence of precipitation worsens the situation, causing a 0.4-km-deeper algorithm-detected blind zone for the DPR at the Huancayo Observatory. In the study area, the depth of the clutter layer observed with DPR often extends above the melting layer but can be highly variable, extending even as high as 5 km AGL. These results suggest that DPR estimates of stratiform precipitation over the Andes Mountains are likely underestimated because of the terrain effects on the satellite measurements and problems in its blind zone detection algorithms, highlighting the difficulty in estimating precipitation in mountainous terrain from spaceborne radar.
Start page
441
End page
456
Volume
61
Issue
4
Language
English
OCDE Knowledge area
Sensores remotos Investigación climática Geografía física
Scopus EID
2-s2.0-85130593869
Source
Journal of Applied Meteorology and Climatology
ISSN of the container
15588424
Sponsor(s)
Thanks are given to Instituto Geofísco del Perú staff for their help with radar maintenance and data collection of MIRA-35C and BLTR. This study comes under the project “MAGNET-IGP: Strengthening the research line in physics and microphysics of the atmosphere (Agreement 010-2017-FONDECYT).” This work was done using computational resources of the HPC-Linux Cluster from the Laboratorio de Dinmica de Fluidos Geofísicos Computacionales at Instituto Geofísico del Perú (Grants 101-2014-FONDECYT, SPIRALES2012 IRD-IGP, Man-glares IGP-IDRC, PP068 program). Authors Gatlin and Petersen thank NASA’s GPM project for continued Cal/Val support. We gratefully thank anonymous reviewer 1 for the very careful reading of this paper and constructive comments that helped improve its quality.
Sources of information: Directorio de Producción Científica Scopus