Sofradir detectors to aid climate model uncertainty
Sofradir, the maker of mercury cadmium telluride (MCT) detectors, has won a €3.2 million ($4.2 million) supply contract with NEC Toshiba Space.
France-based Sofradir will deliver a custom bi-spectral long-wave infrared detector for a satellite observation project that is expected to improve the climate models used to predict environmental changes.
MCT chips will sit at the heart of the second-generation global imager (SGLI), which will be one of three instruments on board the observation platform. The long-wave imager includes two focal plane arrays centered at 10.8 µm and 12 µm.
"The purpose of the SGLI is to conduct detailed global monitoring of the ground surface, as well as the middle and lower atmospheres, to allow scientists to observe and better predict the future courses of global environmental changes due to natural fluctuations and those caused by mankind," says Sofradir.
It will deliver the detector in 2009, although the launch of the Global Change Observation Mission (GCOM) satellite that will carry it is not expected until 2012.
When deployed, the GCOM mission is to measure geophysical features such as the optical thickness of clouds and aerosols in the atmosphere, thermal fluxes, and the sources and sinks of greenhouse gases.
Although very sophisticated, the climate models that are currently being used to predict the impact of carbon dioxide concentration on global temperatures are too crude to take all of the physical influences into account.
According to climate modelers at the UK s Met Office writing in a recent issue of Physics World (see related article), that is because some processes that influence our climate occur on smaller spatial or shorter temporal scales than the resolution of these models.
For example, clouds can heat the atmosphere by releasing latent heat, and they also interact strongly with infrared and visible radiation. But most clouds are hundreds of times smaller than the typical computer-model resolution. If clouds were modelled incorrectly, climate simulations would be seriously in error, says the Met Office team.
Although modelers can use complex mathematical techniques to take account of these local, transient effects, data from the satellite observations are expected to greatly improve the reliability of the models.
Sofradir recently announced plans to double its MCT detector output thanks to a new €9 million facility where it will make the chips on 4-inch wafers using MBE (see related story).
