Open AccessOpportunistic Constant Target Matching—A New Method for Satellite Intercalibration
Author(s) -
Buehler Stefan A.,
Prange Marc,
Mrziglod John,
John Viju O.,
Burgdorf Martin,
Lemke Oliver
Publication year - 2020
Publication title -
earth and space science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.843
H-Index - 23
ISSN - 2333-5084
DOI - 10.1029/2019ea000856
Subject(s) - satellite , remote sensing , nadir , geostationary orbit , brightness temperature , computer science , matching (statistics) , meteorology , channel (broadcasting) , constant (computer programming) , environmental science , depth sounding , microwave , mathematics , statistics , geology , telecommunications , physics , aerospace engineering , engineering , oceanography , programming language
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.