Retrieval of Cloud Liquid Water Path from MSU-GS Data Onboard Arktika-M 1

Abstract

This paper presents a method for cloud water path retrieval from daytime MSU-GS measurements onboard the Russian hydrometeorological satellite Arktika-M 1. The technique is based on the physical principles of the interaction of electromagnetic radiation with cloud particles at wavelengths of 0.55 and 4.0 μm. Cloud water path estimates obtained from the MSU-GS radiometer are compared with similar estimates from the AMSU/MHS and AHI radiometer data. Based on the results of the comparison, the required estimates of the cloud water path of drop clouds are within the permissible limits of the measurement error, not exceeding 50 g/m². At the same time, due to its design features, the MSU-GS radiometer does not allow retrieving the cloud water path of ice clouds with the required accuracy. On average, the cloud water path estimate of ice clouds according to the MSU-GS data is underestimated by 110 g/m², and the root-mean-square error is 158 g/m², when compared to the AHI radiometer data. The estimates of the cloud water path are introduced into the geographic information system Arktika-M, which provides access to the Arktika-M 1 data and the results of their thematic processing in a near real time mode.