Gerhard Meister

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Ocean-color applications require maximum uncertainties in blue-wavelength water-leaving radiances in oligotrophic ocean of approximately 5%. Water-leaving radiances from Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite, however, exhibit temporal drift of the order of 15% as well as sensor changes in response versus scan and(More)
The Collection 6 (C6) MODIS (Moderate Resolution Imaging Spectroradiometer) land and atmosphere data sets are scheduled for release in 2014. C6 contains significant revisions of the calibration approach to account for sensor aging. This analysis documents the presence of systematic temporal trends in the visible and near-infrared (500 m) bands of the(More)
The NASA ocean color products of SeaWiFS and MODIS Aqua have been reprocessed in 2009 and 2010, respectively. This paper describes the changes to the calibration approach for MODIS Aqua. Due to a significant downward trend in the operational MODIS Aqua water-leaving radiances at 412nm, the previous calibration approach was no longer sufficient. The new(More)
The Sea-Viewing Wide-Field-of-View Sensor (SeaWiFS) has made monthly observations of the Moon since 1997. Using 66 monthly measurements, the SeaWiFS calibration team has developed a correction for the instrument's on-orbit response changes. Concurrently, a lunar irradiance model has been developed by the U.S. Geological Survey (USGS) from extensive(More)
Observations of the Moon provide a primary technique for the on-orbit cross calibration of Earth remote sensing instruments. Monthly lunar observations are major components of the on-orbit calibration strategies of SeaWiFS and MODIS. SeaWiFS has collected more than 132 low phase angle and 59 high phase angle lunar observations over 12 years, Terra MODIS has(More)
Remotely sensed images with a pixel size of about 1 m can nowadays be acquired by airborne scanners and in the near future also by high resolution satellites. With such a high spatial resolution, remotely sensed data of urban areas can resolve structures like a roof into the different surface segments with different inclinations, e.g. in the case of a(More)
Ocean color climate data records (CDRs) require water-leaving radiances with 5% absolute and 1% relative accuracies as input. Because of the amplification of any sensor calibration errors by the atmospheric correction, the 1% relative accuracy requirement translates into a 0.1% long-term radiometric stability requirement for top-of-the-atmosphere (TOA)(More)
This paper presents results from analyzing hyperspectral BRDF data of grass lawn and watercress. The intensity of the hotspot as a function of wavelength is determined from fitting an empirical (or rather phenomenological) model to the data. The model consists of a lambertian, bowlshape, hotspot and forward scattering component. An analytical, theoretically(More)
The NASA Ocean Biology Processing Group (OBPG) developed two independent calibrations of the Suomi National Polar-Orbiting Partnership (SNPP) Visible Infrared Imaging Radiometer Suite (VIIRS) moderate resolution reflective solar bands using solar diffuser measurements and lunar observations, and implemented a combined solar- and lunar-based calibration to(More)