Assimilation of Surface-Sensitive Radiance Observations over Land from Multiple Infrared Sensors

This presentation reports on recent progress toward the assimilation of surface sensitive infrared radiances over land at the Canadian Meteorological Center. Starting with AIRS and IASI from METOP-A (presented at the last annual AMS meeting), the assimilation now includes IASI from METOP-B and Cris from Suomi NPP. It is shown that these added observations, on top of all data assimilated operationally, impacts significantly on global analysis and forecasts up to 5 days and more. A detailed spectral emissivity database from MODIS is used. It was realized that the surface model which provides background fields of surface skin and 2-m temperature uses a constant surface emissivity of 0.95. For consistency, a new broadband emissivity was derived from the MODIS database and used in the model. This defines a new control experiment while the test experiment differs only by adding the surface sensitive observations from the four hyperspectral sounders. Results from a two-month assimilation cycle using the newly implemented Canadian 4D ensemble-variational system will be presented.