English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The Tropospheric Monitoring Instrument(TROPOMI) spectrometer is the single payload of the CopernicusSentinel 5 Precursor (S5P) mission. It measures Earth radiancespectra in the shortwave infrared spectral range around2.3 µm with a dedicated instrument module. These measurementsprovide carbon monoxide (CO) total column densities over land, which forclear sky conditions are highly sensitive to the tropospheric boundarylayer. For cloudy atmospheres over land and ocean, the column sensitivity changesaccording to the light path through the atmosphere. In this study,we present the physics-based operational S5P algorithm to inferatmospheric CO columns satisfying the envisaged accuracy( <  15 %) and precision ( <  10 %) both for clear sky andcloudy observations with low cloud height. Here, methane absorptionin the 2.3 µm range is combined with methane abundances froma global chemical transport model to infer information onatmospheric scattering. For efficient processing, we deploy alinearized two-stream radiative transfer model as forward model and a profile scalingapproach to adjust the CO abundance in the inversion. Based ongeneric measurement ensembles, including clear sky and cloudyobservations, we estimated the CO retrieval precision to be ≤  11 % for surface albedo  ≥  0.03 and solar zenith angle ≤  70°. CO biases of  ≤  3 % are introduced byinaccuracies in the methane a priori knowledge. For stronglyenhanced CO concentrations in the tropospheric boundary layer andfor cloudy conditions, CO errors in the order of 8 % can beintroduced by the retrieval of cloud parameters of our algorithm.Moreover, we estimated the effect of a distorted spectral instrumentresponse due to the inhomogeneous illumination of the instrumententrance slit in the flight direction to be  <  2 % withpseudo-random characteristics when averaging over space andtime. Finally, the CO data exploitation is demonstrated for aTROPOMI orbit of simulated shortwave infrared measurements. Overall,the study demonstrates that for an instrument that performs incompliance with the pre-flight specifications, the CO product willmeet the required product performance well

Carbon monoxide total column retrievals from TROPOMI shortwave infrared measurements