Opportunistic Constant Target Matching—A New Method for Satellite Intercalibration

Earth and Space Science

Viju O. John¹  Stefan A. Buehler²  Martin Burgdorf²  Oliver Lemke²  Marc Prange²  John Mrziglod³ 

[1] European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) Frascati Italy;Meteorologisches Institut, Centrum für Erdsystem‐ und Nachhaltigkeitsforschung (CEN), Fachbereich Geowissenschaften Universität Hamburg Hamburg Germany;Φ‐Lab, European Space Agency (ESA) Hamburg Germany;

关键词: satellite;    calibration;    collocation;    microwave;    infrared;   

DOI  :  10.1029/2019EA000856

来源: DOAJ

【 摘 要 】

Abstract Opportunistic constant target matching is a new method for satellite intercalibration. It solves a long‐standing issue with the traditional simultaneous nadir overpass (SNO) method, namely, that it typically provides only data points with cold brightness temperatures for humidity sounding instruments on sun‐synchronous satellites. In the new method, a geostationary infrared sensor (SEVIRI) is used to select constant target matches for two different microwave sensors (MHS on NOAA 18 and Metop A). We discuss the main assumptions and limitations of the method and explore its statistical properties with a simple Monte Carlo simulation. The method was tested in a simple case study with real observations for this combination of satellites for MHS Channel 3 at 183 ± 1 GHz, the upper tropospheric humidity channel. For the studied 3‐month test period, real observations are found to behave consistently with the simulations, increasing our confidence that the method can be a valuable tool for intercalibration efforts. For the selected case study, the new method confirms that the bias between NOAA 18 and Metop A MHS Channel 3 is very small, with absolute value below 0.05 K.

【 授权许可】

Unknown