Heritage & Future
SENTINEL-5P continues a series of spectrometers that were or are currently measuring atmospheric properties since 1995 until today:
SENTINEL-5P will extend the data records of these missions and will be followed by the SENTINEL-5 missions, planned for launch in 2021 onwards.
The mission forms the link between the current missions and the future SENTINEL-4 and SENTINEL-5 missions.
GOME(-2), SCIAMACHY, OMI and TROPOMI are passive sun backscatter spectrometers. SCIAMACHY and GOME(-2) use a scanning concept and linear detector arrays whereas OMI uses a staring push-broom concept with two-dimension detector arrays. The staring push-broom concept measures all ground pixels in the swath simultaneously and allows improved spatial resolution. SCIAMACHY measurements cover almost the entire solar irradiance spectrum from UV to SWIR (240 to 2 400 nm) whereas GOME(-2) and OMI are scaled down in terms of wavelength range covering respectively the UV-VIS-NIR range (270 – 790 nm) and the UV-VIS range (270-500 nm). The main characteristics of these four heritage instruments are summarised in Table 1.
Table 1: Main Characteristics of SENTINEL-5P Heritage Instruments
TROPOMI employs the best of its predecessors by combining:
When compared to these heritage instruments, the 7×7 km2 spatial resolution at nadir and the improved signal-to-noise ratio of the TROPOMI instrument allows detection of small-scale sources, and increases the fraction of cloud-free observations. This represents a significant step forward in meeting the challenging requirements for SENTINEL-5.