Retrieval of Cloud Microphysical Properties from MODIS and AIRS

Abstract

The Moderate Resolution Imaging Spectroradiometer (MODIS) and the Atmospheric Infrared Sounder (AIRS) measurements from the NASA Earth Observing System Aqua satellite enable global monitoring of the distribution of clouds during day and night. The MODIS is able to provide a high-spatial-resolution (1-5 km) cloud mask, cloud classification mask, cloud-phase mask, cloud-top pressure (CTP), and effective cloud amount during both the daytime and the nighttime, as well as cloud particle size (CPS) and cloud optical thickness (COT) at 0.55 m during the daytime. The AIRS high-spectral-resolution measurements reveal cloud properties with coarser spatial resolution (13.5 km at nadir). Combined, MODIS and AIRS provide cloud microphysical properties during both the daytime and nighttime. A fast cloudy radiative transfer model for AIRS that accounts for cloud scattering and absorption is described in this paper. Onedimensional variational (1DVAR) and minimum-residual (MR) methods are used to retrieve the CPS and COT from AIRS longwave window region (790-970 cm Ϫ1 or 10.31-12.66 m, and 1050-1130 cm Ϫ1 or 8.85-9.52 m) cloudy radiance measurements. In both 1DVAR and MR procedures, the CTP is derived from the AIRS radiances of carbon dioxide channels while the cloud-phase information is derived from the collocated MODIS 1-km phase mask for AIRS CPS and COT retrievals. In addition, the collocated 1-km MODIS cloud mask refines the AIRS cloud detection in both 1DVAR and MR procedures. The atmospheric temperature profile, moisture profile, and surface skin temperature used in the AIRS cloud retrieval processing are from the European Centre for Medium-Range Weather Forecasts forecast analysis. The results from 1DVAR are compared with the operational MODIS products and MR cloud microphysical property retrieval. A Hurricane Isabel case study shows that 1DVAR retrievals have a high correlation with either the operational MODIS cloud products or MR cloud property retrievals. 1DVAR provides an efficient way for cloud microphysical property retrieval during the daytime, and MR provides the cloud microphysical property retrievals during both the daytime and nighttime.

Ash and ice clouds during the Mt Kelud February 2014 eruption as interpreted from IASI and AVHRR/3 observations

“…Hyperspectral infrared sounders may be used to detect cloud microphysical properties. For example Li et al (2005) retrieved cloud microphysical properties from MODIS and the Atmospheric Infrared Sounder (AIRS). However, no such attempt was made here.…”

A Detailed Cloud Fraction Climatology of the Upper Indus Basin and Its Implications for Near-Surface Air Temperature*

“…Thus, although the remote sensing algorithms may at times produce false positives or negatives, these data products can be considered as observations. This paper presents detailed analysis of a moderate resolution (5 km) cloud data product (MOD06L2, version 5.1) produced from MODIS imagery (Platnick et al 2003;Li et al 2005;Weisz et al 2007) for a period covering 2000 to 2012. Data were downloaded from the NASA Level 1 and Atmosphere Archive and Distribution System (LAADS).…”

Synergistic use of AIRS and MODIS for dust top height retrieval over land

“…The advantage of the 1DVAR algorithm is that it can easily include more inputs in the retrieval and simultaneously takes into account uncertainties in the radiative transfer model, instrument measurement and other effects in the inverse process. This retrieval method has been used to infer cloud parameters by combining AIRS and MODIS by Li et al (2004Li et al ( , 2005.…”

“…There are 240 granules available over 24 hours, each of which includes 135 scans. Although its primary purpose is to derive atmospheric temperature and humidity profiles, it has been used to infer cloud properties (Li et al, 2005) and dust properties over oceans (Pierangelo et al, 2004;De Souza-Machado et al, 2006;Peyridieu et al, 2010;De Souza-Machado et al, 2010) and over land (Yao et al, 2012;Han and Sohn, 2013).…”