Sensitivity of 89–190-GHz Microwave Observations to Ice Particle ScatteringSource: Journal of Applied Meteorology and Climatology:;2020:;volume( 59 ):;issue: 007::page 1195Author:Chen, Ruiyao;Bennartz, Ralf
DOI: 10.1175/JAMC-D-19-0293.1Publisher: American Meteorological Society
Abstract: The sensitivity of microwave brightness temperatures (TBs) to hydrometeors at frequencies between 89 and 190 GHz is investigated by comparing Fengyun-3C (FY-3C) Microwave Humidity Sounder-2 (MWHS-2) measurements with radar reflectivity profiles and retrieved products from the Global Precipitation Measurement mission’s Dual-Frequency Precipitation Radar (DPR). Scattering-induced TB depressions (ΔTBs), calculated by subtracting simulated cloud-free TBs from bias-corrected observed TBs for each channel, are compared with DPR-retrieved hydrometeor water path (HWP) and vertically integrated radar reflectivity ZINT. We also account for the number of hydrometeors actually visible in each MWHS-2 channel by weighting HWP with the channel’s cloud-free gas transmission profile and the observation slant path. We denote these transmission-weighted, slant-path-integrated quantities with a superscript asterisk (e.g., HWP*). The so-derived linear sensitivity of ΔTB with respect to HWP* increases with frequency roughly to the power of 1.78. A retrieved HWP* of 1 kg m−2 at 89 GHz on average corresponds to a decrease in observed TB, relative to a cloud-free background, of 11 K. At 183 GHz, the decrease is about 34–53 K. We perform a similar analysis using the vertically integrated, transmission-weighted slant-path radar reflectivity Z*INT and find that ΔTB also decreases approximately linearly with (Z*INT)0.58. The exponent of 0.58 corresponds to the one we find in the purely DPR-retrieval-based ZINT–HWP relation. The observed sensitivities of ΔTB with respect to Z*INT and HWP* allow for the validation of hydrometeor scattering models.
|
Collections
Show full item record
contributor author | Chen, Ruiyao;Bennartz, Ralf | |
date accessioned | 2022-01-30T17:48:58Z | |
date available | 2022-01-30T17:48:58Z | |
date copyright | 7/6/2020 12:00:00 AM | |
date issued | 2020 | |
identifier issn | 1558-8424 | |
identifier other | jamcd190293.pdf | |
identifier uri | http://yetl.yabesh.ir/yetl1/handle/yetl/4263984 | |
description abstract | The sensitivity of microwave brightness temperatures (TBs) to hydrometeors at frequencies between 89 and 190 GHz is investigated by comparing Fengyun-3C (FY-3C) Microwave Humidity Sounder-2 (MWHS-2) measurements with radar reflectivity profiles and retrieved products from the Global Precipitation Measurement mission’s Dual-Frequency Precipitation Radar (DPR). Scattering-induced TB depressions (ΔTBs), calculated by subtracting simulated cloud-free TBs from bias-corrected observed TBs for each channel, are compared with DPR-retrieved hydrometeor water path (HWP) and vertically integrated radar reflectivity ZINT. We also account for the number of hydrometeors actually visible in each MWHS-2 channel by weighting HWP with the channel’s cloud-free gas transmission profile and the observation slant path. We denote these transmission-weighted, slant-path-integrated quantities with a superscript asterisk (e.g., HWP*). The so-derived linear sensitivity of ΔTB with respect to HWP* increases with frequency roughly to the power of 1.78. A retrieved HWP* of 1 kg m−2 at 89 GHz on average corresponds to a decrease in observed TB, relative to a cloud-free background, of 11 K. At 183 GHz, the decrease is about 34–53 K. We perform a similar analysis using the vertically integrated, transmission-weighted slant-path radar reflectivity Z*INT and find that ΔTB also decreases approximately linearly with (Z*INT)0.58. The exponent of 0.58 corresponds to the one we find in the purely DPR-retrieval-based ZINT–HWP relation. The observed sensitivities of ΔTB with respect to Z*INT and HWP* allow for the validation of hydrometeor scattering models. | |
publisher | American Meteorological Society | |
title | Sensitivity of 89–190-GHz Microwave Observations to Ice Particle Scattering | |
type | Journal Paper | |
journal volume | 59 | |
journal issue | 7 | |
journal title | Journal of Applied Meteorology and Climatology | |
identifier doi | 10.1175/JAMC-D-19-0293.1 | |
journal fristpage | 1195 | |
journal lastpage | 1215 | |
tree | Journal of Applied Meteorology and Climatology:;2020:;volume( 59 ):;issue: 007 | |
contenttype | Fulltext |