Characteristics of cloud liquid water path from SEVIRI onboard the Meteosat Second Generation 2 satellite for several cloud types

Abstract

Abstract. In this study the temporal and spatial characteristics of the liquid water path (LWP) of low, middle and high level clouds are analysed using space-based observations from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) instrument onboard the Meteosat Second Generation 2 (MSG 2) satellite. Both geophysical quantities are part of the CLAAS (CLoud property dAtAset using SEVIRI) data set and are generated by EUMETSAT's Satellite Application Facility on Climate Monitoring (CM SAF). In this article we focus on the statistical properties of LWP, retrieved during daylight conditions, associated with individual cloud types. We analysed the intrinsic variability of LWP, that is, the variability in only cloudy regions and the variations driven by cloud amount. The relative amplitude of the intrinsic diurnal cycle exceeded the cloud amount driven amplitude in our analysed cases. Our results reveal that each cloud type possesses a characteristic intrinsic LWP distribution. These frequency distributions are constant with time in the entire SE-VIRI field of view, but vary for smaller regions like Central Europe. Generally the average LWP is higher over land than over sea; in the case of low clouds this amounts to 15-27 % in 2009. The variance of the frequency distributions is enhanced as well. Also, the average diurnal cycle of LWP is related to cloud type with the most pronounced relative diurnal variations being detected for low and middle level clouds. Maps of the relative amplitude and the local time of maximum LWP show the variation throughout the SEVIRI field of view.

Sensitivity study of the planetary boundary layer and microphysical schemes to the initialization of convection over the Arabian Peninsula

“…Following Kniffka et al . (), a cloud is present in the model if CWP 0.05 mm. If this is true for a model grid box, then this grid box is assigned a value of 1.…”

“…As CWP is derived from optical depth data using the relation from Stephens () depending on optical depth, we discard all observations showing CWP values less than 0.05 mm (Kniffka et al . ).…”

“…According to the validation report (Finkensieper et al 2016a), the accuracy of the CWP product is 10 g⋅m −2 . As CWP is derived from optical depth data using the relation from Stephens (1978) depending on optical depth, we discard all observations showing CWP values less than 0.05 mm (Kniffka et al 2014).…”

Evaluating the diurnal cycle of South Atlantic stratocumulus clouds as observed by MSG SEVIRI

“…Previous research (Hobbs, 2002;McGill et al, 2003;Wilcox, 2010) has shown that the smoke is typically located in layers (at 2 to 4 km altitude) that are vertically separated from the Sc clouds below (at ∼ 1.5 km altitude) and, hence, direct microphysical interaction between the aerosols and the Sc is often inhibited by the strong temperature inversion above the cloud layer. However, more recent studies, e.g., Rajapakshe et al (2017), reported that smoke layers are closer to the cloud layer and significantly enhance the brightness of stratocumulus (Lu et al, 2018). Recently, several studies evaluated the dynamical and climatological impacts of the presence of smoke above Sc clouds from both modeling as well as satellite and/or field campaign measurements (Adebiyi et al, 2015;Adebiyi and Zuidema, 2016;Zuidema et al, 2016;Horowitz et al, 2017;Chang and Christopher, 2017;Lu et al, 2018;Kar et al, 2018).…”

“…face temperatures (SSTs), within a shallow, well-mixed MBL capped by strong subsidence and a strong temperature inversion (e.g., Albrecht et al, 1995;Norris, 1998;Wood and Hartmann, 2006;Sandu et al, 2010). Several studies investigated the synoptic to inter-annual variability and the driving mechanisms of these clouds from both an observational and a modeling perspective (e.g., Klein and Hartmann, 1993;Klein et al, 1995;Bretherton and Wyant, 1997;Wood and Bretherton, 2006;Eastman et al, 2011;Wood, 2012;Painemal et al, 2012Painemal et al, , 2013aPainemal et al, , 2015Adebiyi et al, 2015;Adebiyi and Zuidema, 2016;Horowitz et al, 2017;Kar et al, 2018;Lu et al, 2018).…”