A microwave satellite water vapour column retrieval for polar winter conditions

Abstract

Abstract.A new microwave satellite water vapour retrieval for the polar winter atmosphere is presented. The retrieval builds on the work of Miao et al. (2001) and Melsheimer and Heygster (2008), employing auxiliary information for atmospheric conditions and numerical optimization. It was tested using simulated and actual measurements from the Microwave Humidity Sounder (MHS) satellite instruments. Ground truth was provided by the G-band vapour radiometer (GVR) at Barrow, Alaska. For water vapour columns less than 6 kg m −2 , comparisons between the retrieval and GVR result in a root mean square (RMS) deviation of 0.39 kg m −2 and a systematic bias of 0.08 kg m −2 . These results are compared with RMS deviations and biases at Barrow for the retrieval of Melsheimer and Heygster (2008), the AIRS and MIRS satellite data products, and the ERA-Interim, NCEP, JRA-55, and ASR reanalyses. When applied to MHS measurements, the new retrieval produces a smaller RMS deviation and bias than for the earlier retrieval and satellite data products. The RMS deviations for the new retrieval were comparable to those for the ERA-Interim, JRA-55, and ASR reanalyses; however, the MHS retrievals have much finer horizontal resolution (15 km at nadir) and reveal more structure. The new retrieval can be used to obtain pan-Arctic maps of water vapour columns of unprecedented quality.

Towards the Marine Arctic Component of the Pan-Eurasian Experiment

“…We also expect further advance in ground/ship/ice-based remote sensing of the Arctic atmosphere, as the methods introduced in Section 3.2 are progressively improving. Further, recent advance in satellite remote sensing has yielded better information on the temperature and humidity profiles over ice and snow (Perro et al, 2016). 30…”

Pan-Arctic measurements of wintertime water vapour column using a satellite-borne microwave radiometer

“…Here we present pan-Arctic water vapour column obtained from wintertime satellite microwave measurements made with the ATMS between January 2012 and March 2015 (December to March inclusive). Water vapour columns were determined using an updated version of the retrieval presented by Perro et al (2016). The retrieval builds on the work of Miao et al (2001) and Melsheimer and Heygster (2008) by employing auxiliary information for atmospheric conditions and numerical optimization.…”

“…ATMS measurements from the Suomi-NPP satellite are used exclusively in this study. ATMS is the sucessor to MHS, the instrument considered in the study by Perro et al (2016). All five 183 GHz dual-band channels, the 165.5 GHz channel and the 88.2 GHz channel of ATMS are used.…”

“…In this paper, the ATMS water vapour columns are validated against surface-based measurements from two different instruments: the G-band Vapor Radiometer (GVR) at Barrow, Alaska (similar to the work of Perro et al (2016)) and the Extended-Range Atmospheric Emitted Radiance Interferometer (E-AERI) at Eureka, Nunavut (80.0 • N, 85.9 • W). The ATMS-derived vater vapour columns are subsequently compared to those from the Arctic radiosonde network and multiple reanalyses, including the new ERA5 product from the European Centre for Medium-Range Weather Forecasts (ECMWF).…”

“…The structure of this paper is as follows. Section 2 describes the updates made to the microwave water vapour retrieval of Perro et al (2016) for the purposes of high-latitude measurements (some details are relegated to Appendix A). In Sec.…”