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IASI dataset v1
dataset
posted on 2020-09-30, 12:45 authored by David Malmgren-Hansen, Valero Laparra, Gustau Camps-Valls, Xavier CalbetThe Infrared Atmospheric Sounding Interferometer (IASI) on board the MetOp satellite series measures the infrared spectrum with high resolution. The ground footprint resolution of the instruments is 12 km at nadir, and a spectral resolution of 0.25cm −1 in the spectrum between 645 cm −1 and 2760 cm −1 . This results in 8461 spectral samples covering 2200km scan-swath with 60 points per line. IASI is an ideal instrument for monitoring different physical/chemical parameters in the atmosphere e.g. temperature, humidity and trace gases such as ozone. Energy from different altitudes returns a different spectral shift. In this way atmospheric profiles can be obtained and these provides important information for e.g. Numerical Weather Models. In the IASI dataset, channel selection has been performed reducing spectral components from its 8461 channels to 4699, before any further processing. For statistical modelling of atmospheric parameters, forecast models are used to provide dense target values for every point observed by IASI. The IASI dataset has been matched with forecasts by the Medium-Range Weather Forecasts (ECMWF) model. This includes temperatures, humidity, and ozone concentrations for 137 altitudes through the atmosphere. EUMETSAT which operates the MetOp satellites uses forecasting data together with IASI measurements to provide derived products. These retrievals are validated both on the forecasts and in-situ measurements from e.g. radiosondes. Temperatures can be derived down to 1K accuracy, humidity with 10% and ozone with 5%, all at 25km ground resolution.
The time of the samples for this dataset is the august 16 2013 and august 17 2013 with one orbit and 13 orbits respectively. The data is stored in blocks of 60x60 spatial pixels with 4699 spectral channels. The filename specifier,
XXXX can be "data" (the IASI recording), "TP" (Temperature profiles), "WP" (Water Pressure profiles), "OC" (Ozone concentration profiles), hPa (atm. air pressure profiles), "['C_F', 'ZA', 'lat', 'lon', 'SP', 'SCG', 'L_F']" (Cloud Fraction, Zenith Angle, Lattitude, Longitude, Surface Pressure, ..., Land Fraction)
More instructions and code for using this dataset can be found on the github page link below.
The time of the samples for this dataset is the august 16 2013 and august 17 2013 with one orbit and 13 orbits respectively. The data is stored in blocks of 60x60 spatial pixels with 4699 spectral channels. The filename specifier,
20130817210256_NN_XXXX.npy
refers first to the date-time stamp. the NN refers to the block number in the orbit which starts and ends near the north pole. A full orbit is 1260 pixels along track and 60 pixels across track, so one orbit is split in 1260/60=21 files. Recordings shorter or longer than one full orbit can occur.
XXXX can be "data" (the IASI recording), "TP" (Temperature profiles), "WP" (Water Pressure profiles), "OC" (Ozone concentration profiles), hPa (atm. air pressure profiles), "['C_F', 'ZA', 'lat', 'lon', 'SP', 'SCG', 'L_F']" (Cloud Fraction, Zenith Angle, Lattitude, Longitude, Surface Pressure, ..., Land Fraction)
More instructions and code for using this dataset can be found on the github page link below.
