On the distinctiveness of observed oceanic raindrop distributions
Artikel i vetenskaplig tidskrift, 2019

Representation of the drop size distribution (DSD) of rainfall is a key element of characterizing precipitation in models and observations, with a functional form necessary to calculate the precipitation flux and the drops' interaction with radiation. With newly available oceanic disdrometer measurements, this study investigates the validity of commonly used DSDs, potentially useful a priori constraints for retrievals, and the impacts of DSD variability on radiative transfer. These data are also compared with leading satellite-based estimates over ocean, with the disdrometers observing a larger number of small drops and significantly more variability in number concentrations. This indicates that previous appraisals of raindrop variability over ocean may have been underestimates. Forward model errors due to DSD variability are shown to be significant for both active and passive sensors. The modified gamma distribution is found to be generally adequate to describe rain DSDs but may cause systematic errors for high-latitude or stratocumulus rain retrievals. Depending on the application, an exponential or generalized gamma function may be preferable for representing oceanic DSDs. An unsupervised classification algorithm finds a variety of DSD shapes that differ from commonly used DSDs but does not find a singular set that best describes the global variability.

Författare

David Duncan

Chalmers, Rymd-, geo- och miljövetenskap, Mikrovågs- och optisk fjärranalys

Patrick Eriksson

Chalmers, Rymd-, geo- och miljövetenskap, Mikrovågs- och optisk fjärranalys

Simon Pfreundschuh

Chalmers, Rymd-, geo- och miljövetenskap, Mikrovågs- och optisk fjärranalys

Christian Klepp

Universität Hamburg

Daniel C. Jones

British Antarctic Survey

Atmospheric Chemistry and Physics

1680-7316 (ISSN) 1680-7324 (eISSN)

Vol. 19 10 6969-6984

Preparation for Metop SG Ice Cloud Imager

Rymdstyrelsen (277/13), 2016-01-01 -- 2018-12-31.

Rymdstyrelsen (169/16), 2017-01-01 -- 2018-12-31.

Ämneskategorier

Meteorologi och atmosfärforskning

Oceanografi, hydrologi, vattenresurser

Multidisciplinär geovetenskap

DOI

10.5194/acp-19-6969-2019

Mer information

Senast uppdaterat

2019-06-11