Advanced Along Track Scanning Radiometer (AATSR)


The Advanced Along-Track Scanning Radiometer (AATSR) is a space-borne multi-channel imaging radiometer with the main purpose of providing highly accurate global data on sea surface temperature (SST) and land surface temperature (LST). The AATSR instrument was launched in 2002 onboard of the European Space Agency's (ESA) ENVISAT satellite as the third in a series of instruments in order to continue the data record acquired by its predecessors, the ATSR-1 and ATSR-2 instruments onboard the ERS-1 and ERS-2 platforms.

AATSR measures reflected and emitted radiation at wavelengths of 0.55 µm, 0.66 µm, 0.87 µm, 1.6 µm, 3.7 µm, 11 µm and 12 µm at both a nadir and a forward view angle (Llewellyn-Jones et al., 2001). The instrument is equipped with a highly precise on-board calibration system designed for stability of the reference target.

Previous validation efforts have indidacted that AATSR is able to provide sea surface temperature with errors of less than 0.3 K (Corlett et al., 2006) and nighttime LST with errors of less than 1 K (Coll et al., 2005). The standard errors of daytime and nighttime LST over inland water bodies derived from ATSR-2 have been found to be as low as 0.33 K and 0.28 K, respectively (Hook et al., 2003).

Sea and Land Surface Temperature
Radiometer (SLSTR)

The Sea and Land Surface Temperature Radiometer (SLSTR) is an upcoming instrument designed for continuing and improving the SST and LST record provided by the three (A)ATSR sensors and to provide an operational spaceborne platform for temperature observations of the Earth surface. 

SLSTR will be launched in 2014 onboard of the first of the series of Sentinel-3 satellites which comprise an element of the Global Monitoring for Environment and Security (GMES) programme. This programme responds to the requirements for an operational and near-real-time monitoring of the Earth surface over a period of 15 to 20 years. Based on the heritage of the (A)ATSR series of instruments, SLSTR is designed to deliver improved SST and LST measurements by providing additional channels, higher spatial resolution in some channels and a significantly wider swath than AATSR. 

More information about SLSTR and Sentinel-3 can be found here. Technical information about Sentinel-3 is also available in the Sentinel-3 Missions Requirement Document, the Sentinel-3 Mission Requirements Traceability Document, and the Sentinel-3 Facts and Figures brochure.
Other Instruments

Spinning Enhanced Visible and Infrared Imager (SEVIRI)

LST is also being retrieved from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard of the  geostationary Meteosat Second Generation satellites, which are operated jointly by EUMETSAT and ESA.

Due to its geostationary orbit, SEVIRI is able to provide LST observations for Africa and Europe at 15 minute intervals and can therefore provided temporally detailed information about the diurnal cycle of LST.

Details about SEVIRI can be found here and here.

Moderate Resolution Imaging Spectroradiometer (MODIS)

The Moderate Resolution Imaging Spectroradiometer (MODIS) is a key instrument aboard both the Terra and Aqua satellites operated by NASA. The sensor provides operational products of both LST and emissivity. Detailed information about MODIS LST retrieval can be found in the MODIS Land-Surface Temperature Algorithm Theoretical Basis Document.
The ENVISAT satellite pictured here is the platform carrying the AATSR instrument.

Coll, C., Caselles, V., Galve, J., Valor, E., Niclos, R., Sanchez, J., Rivas, R., 2005. Ground measurements for the validation of land surface temperatures derived from AATSR and MODIS data. Remote Sensing of Environment 97, 288-300.

Corlett, G., Barton, I., Donlon, C., Edwards, M., Good, S., Horrocks, L., Llewellynjones, D., Merchant, C., Minnett, P., Nightingale, T., 2006. The accuracy of SST retrievals from AATSR: An initial assessment through geophysical validation against in situ radiometers, buoys and other SST data sets. Advances in Space Research 37, 764-769.

Hook, S.J., Prata, F.J., Alley, R.E., Abtahi, A., Richards, R.C., Schladow, S.G., Pálmarsson, S.Ó., 2003. Retrieval of Lake Bulk and Skin Temperatures Using Along-Track Scanning Radiometer (ATSR-2) Data: A Case Study Using Lake Tahoe, California. Journal of Atmospheric and Oceanic Technology 20, 534.

Llewellyn-Jones, D., Edwards, M., Mutlow, C., Birks, A., Barton, I., Tait, H., 2001. AATSR: global-change and surface-temperature measurements from ENVISAT. ESA bulletin 105, 10–21.