The operational IASI Level 2 processor Original Research Article

The Infrared Atmospheric Sounding Radiometer (IASI) will be flown on board the Metop satellite in the frame of the EUMETSAT Polar System (EPS). The Operational IASI Level 2 Product Processing Facility will be part of the EPS Core Ground Segment. Starting with IASI Level 1 data the Level 2 processor generates high-resolution vertical profiles of temperature and humidity, ozone columns of deep layers, and columnar amounts of carbon monoxide, methane, nitrous oxide, and carbon dioxide, along with surface temperature, surface emissivity, cloud amount, cloud-top height, and cloud phase. Besides IASI data the processor also includes information from the companion instruments AVHRR, AMSU-A, MHS, as well as Level 2 products from the ATOVS instrument suite. The expected accuracy of the temperature and water-vapour profiles in the lower atmosphere is 1 K and 10%, respectively, in clear situations. The clear-sky target accuracy for the total trace gas columns is 1.5–5%.