ML2SO2 is the EOS Aura Microwave Limb Sounder (MLS) standard product for sulfurdioxide derived from radiances measured by the 240 GHz radiometer. The current version is 2.2. Spatial coverage is near-global (-82¬∞ to +82¬∞ latitude), with each profile spaced 1.5¬∞ or ~165 km along the orbit track (roughly 15 orbits per day). The recommended useful vertical range is from 215 to 10 hPa, and the ... vertical resolution is about 3 km. Users of the ML2SO2 data product should read section 3.19 of the EOS MLS Level 2 Version 2.2 Quality Document for more information (http://mls.jpl.nasa.gov/data/v2-2_data_quality_document.pdf).
The data are stored in the version 5 EOS Hierarchical Data Format (HDF-EOS5), which is based on the version 5 Hierarchical Data Format, or HDF5. Each file contains two swath objects (one with profile data, the other with column data), each with a set of data and geolocation fields, swath attributes, and metadata. The data fields include the geophysical parameter values and precision (standard deviation), convergence values, data quality, and a status flag. The geolocation fields include a time stamp in TAI-93 format (seconds since January 1, 1993), geodetic latitude and longitude, and pressure level values, as well as local solar time, solar zenith angle, line of sight angle, and orbit geodetic angle. There is one file per day.
* Massie, S.T., J.C. Gille, C. Craig, R. Khosravi, J. Barnett, W. Read, and D. Winker, "HIRDLS and CALIPSO observations of tropical cirrus", J. Geophys. Res. 114, D00H11, doi:10.1029/2009JD012100, 2010.
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