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Title: Rain retrieval from dual-frequency radar Doppler spectra: validation and potential for a midlatitude precipitating case-study

Abstract

A recently developed technique retrieving the binned raindrop size distributions (DSDs) and air state parameters from ground-based K a and W-band radars Doppler spectra profiles is improved and applied to a typical midlatitude rain event. The retrievals are thoroughly validated against DSD observations of a 2D video disdrometer and independent X-band observations. Here for this case-study, profiles of rain rate, R, mean volume diameter and concentration parameter are retrieved, with low bias and standard deviations. In light rain (0.1 < R < 1 mm h -1), the radar reflectivities must be calibrated with a collocated disdrometer which introduces random errors due to sampling mismatch between the two instruments. The best performances are obtained in moderate rain (1 < R < 20 mm h -1) where the retrieval is providing self-consistent estimates of the absolute calibration and of the attenuation caused by antenna or radome wetness for both radars.

Authors:
ORCiD logo [1]; ORCiD logo [2];  [3];  [4]
  1. Univ. of Leicester (United Kingdom). Dept. of Physics and Astronomy
  2. Univ. of Leicester (United Kingdom). Dept. of Physics and Astronomy; Univ. of Leicester (United Kingdom). Natural Environment Research Council (NERC), National Centre for Earth Observation (NCEO)
  3. Brookhaven National Lab. (BNL), Upton, NY (United States). Atmospheric Sciences Division
  4. Stony Brook Univ., NY (United States). School of Marine and Atmospheric Sciences
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1376170
Report Number(s):
BNL-114145-2017-JA
Journal ID: ISSN 0035-9009; R&D Project: 2016-BNL-EE630EECA-Budg; KP1701000
Grant/Contract Number:
SC0012704; NE/L007169/1
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Quarterly Journal of the Royal Meteorological Society
Additional Journal Information:
Journal Volume: 143; Journal Issue: 704; Journal ID: ISSN 0035-9009
Publisher:
Royal Meteorological Society
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; drop size distribution; rain microphysics; midlatitude precipitation; dual-wavelength radar

Citation Formats

Tridon, F., Battaglia, A., Luke, E., and Kollias, P.. Rain retrieval from dual-frequency radar Doppler spectra: validation and potential for a midlatitude precipitating case-study. United States: N. p., 2017. Web. doi:10.1002/qj.3010.
Tridon, F., Battaglia, A., Luke, E., & Kollias, P.. Rain retrieval from dual-frequency radar Doppler spectra: validation and potential for a midlatitude precipitating case-study. United States. doi:10.1002/qj.3010.
Tridon, F., Battaglia, A., Luke, E., and Kollias, P.. Fri . "Rain retrieval from dual-frequency radar Doppler spectra: validation and potential for a midlatitude precipitating case-study". United States. doi:10.1002/qj.3010. https://www.osti.gov/servlets/purl/1376170.
@article{osti_1376170,
title = {Rain retrieval from dual-frequency radar Doppler spectra: validation and potential for a midlatitude precipitating case-study},
author = {Tridon, F. and Battaglia, A. and Luke, E. and Kollias, P.},
abstractNote = {A recently developed technique retrieving the binned raindrop size distributions (DSDs) and air state parameters from ground-based Ka and W-band radars Doppler spectra profiles is improved and applied to a typical midlatitude rain event. The retrievals are thoroughly validated against DSD observations of a 2D video disdrometer and independent X-band observations. Here for this case-study, profiles of rain rate, R, mean volume diameter and concentration parameter are retrieved, with low bias and standard deviations. In light rain (0.1 < R < 1 mm h-1), the radar reflectivities must be calibrated with a collocated disdrometer which introduces random errors due to sampling mismatch between the two instruments. The best performances are obtained in moderate rain (1 < R < 20 mm h-1) where the retrieval is providing self-consistent estimates of the absolute calibration and of the attenuation caused by antenna or radome wetness for both radars.},
doi = {10.1002/qj.3010},
journal = {Quarterly Journal of the Royal Meteorological Society},
number = 704,
volume = 143,
place = {United States},
year = {Fri Jan 27 00:00:00 EST 2017},
month = {Fri Jan 27 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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