 |
| Titel |
CloudSat-constrained cloud ice water path and cloud top height retrievals from MHS 157 and 183.3 GHz radiances |
| VerfasserIn |
J. Gong, D. L. Wu |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1867-1381
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Measurement Techniques ; 7, no. 6 ; Nr. 7, no. 6 (2014-06-26), S.1873-1890 |
| Datensatznummer |
250115830
|
| Publikation (Nr.) |
 copernicus.org/amt-7-1873-2014.pdf |
|
|
|
|
|
| Zusammenfassung |
| Ice water path (IWP) and cloud top height (ht) are two of the key
variables in determining cloud radiative and thermodynamical properties in
climate models. Large uncertainty remains among IWP measurements from
satellite sensors, in large part due to the assumptions made for cloud
microphysics in these retrievals. In this study, we develop a fast algorithm
to retrieve IWP from the 157, 183.3 ± 3 and 190.3 GHz radiances of the
Microwave Humidity Sounder (MHS) such that the MHS cloud ice retrieval is
consistent with CloudSat IWP measurements. This retrieval is obtained by
constraining the empirical forward models between collocated and coincident
measurements of CloudSat IWP and MHS cloud-induced radiance depression
(Tcir) at these channels. The empirical forward model is
represented by a look-up table (LUT) of Tcir–IWP relationships
as a function of ht and the frequency channel. With
ht simultaneously retrieved, the IWP is found to be more
accurate. The useful range of the MHS IWP retrieval is between 0.5 and
10 kg m−2, and agrees
well with CloudSat in terms of the normalized probability density function
(PDF). Compared to the empirical model, current operational radiative
transfer models (RTMs) still have significant uncertainties in characterizing
the observed Tcir–IWP relationships. Therefore, the empirical
LUT method developed here remains an effective approach to retrieving ice
cloud properties from the MHS-like microwave channels. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|