Traditionally satellite atmospheric remote sensing is performed using dedicated radiometers (e.g., AVHRR, MODIS, MERIS, GLI, MISR, and many others). However, quite recently the use of spectrometers on satellite platforms (with typical spectral resolution of 0.1nm and even better than this) revolutionized atmospheric remote sensing and opened a new era for global atmospheric chemistry and trace gas remote sensing. The high spectral resolution of new orbiting optical instruments made it possible to determine vertical columns of a great variety of atmospheric trace gases such as CO2, CO, CH4, SO2, NO2, O3 and many others on a global scale. This development is of importance for several brunches of modern science and technology including global atmospheric chemistry, climate change and air quality studies. In addition, high spectral resolution is used for vertical profiling of atmospheric aerosol and clouds in atmosphere, which is an important addition to lidar and radar systems currently in operation.
In this talk the review of current methods of trace gas remote sensing based on the differential optical absorption techniques is presented in a great depth. The examples of trace gas vertical columns retrieved using measurements of SCIMACHY on board ENVISAT (ESA) are given. Remote sensing of aerosol and cloud altitudes using spectral measurements in the oxygen A-band is discussed as well.