Emily Berndt

Limb Correction of MODIS and VIIRS Infrared Channels for the Improved Interpretation of RGB Composites

AbstractRed–green–blue (RGB) composite imagery combines information from several spectral channels into one image to aid in the operational analysis of atmospheric processes. However, infrared channels are adversely affected by the limb effect, the result of an increase in optical pathlength of the absorbing atmosphere between the satellite and the earth as viewing zenith angle increases. This study develops a technique to quickly correct for limb effects in both clear and cloudy regions using latitudinally and seasonally varying limb correction coefficients for real-time applications. These limb correction coefficients account for the increase in optical pathlength in order to produce limb-corrected RGB composites. The improved functionality of limb-corrected RGB composites is demonstrated by multiple case studies of Air Mass and Dust RGB composites using Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) and Suomi–National Polar-Orbiting Partnership (SNPP) Visible Infrared Imaging Radiometer Sui...

Development and Application of Atmospheric Infrared Sounder Ozone Retrieval Products for Operational Meteorology

The National Aeronautics and Space Administration Short-term Prediction Research and Transition (SPoRT) Center has worked closely with the Geostationary Operational Environmental Satellite-R series and the Joint Polar Satellite System Proving Grounds to develop and transition unique ozone products derived from Atmospheric Infrared Sounder (AIRS) ozone retrievals to the Ocean Prediction Center (OPC). These products were developed to aid identification of stratospheric air and enhance situational awareness of rapid cyclogenesis and hurricane-force wind events during which stratospheric air may play a key role. OPC forecasters have used the European Organisation for the Exploitation of Meteorological Satellites Meteosat Spinning Enhanced Visible and Infrared Imager red, green, blue (RGB) air mass imagery to identify regions of stratospheric air for their unique weather forecasting challenges; however, the qualitative nature of the new RGB product facilitated a need for quantitative products to enhance forecaster confidence in the RGB air mass imagery. To enhance forecaster interpretation and confidence in the RGB air mass imagery, SPoRT created the total column ozone and ozone anomaly products from hyperspectral infrared sounder ozone retrievals. AIRS Version 6 Level-2 ozone retrievals were utilized to create hourly ozone products over a northwest hemisphere domain. An example case study from February 24-27, 2014, shows the utility of the ozone products in enhancing interpretation of the RGB air mass imagery for anticipating rapid cyclogenesis and hurricane-force winds in the North Atlantic.

Transforming Satellite Data into Weather Forecasts

Teaser: A NASA project spans the gap between research and operations, introducing new composites of satellite imagery to weather forecasters to prepare for the next generation of satellites.

A Methodology to Determine Recipe Adjustments for Multispectral Composites Derived from Next-Generation Advanced Satellite Imagers

AbstractThe European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) began creating multispectral [i.e., red–green–blue (RGB)] composites in the early 2000s with the advent of the Meteosat-8 Spinning Enhanced Visible and Infrared Imager (SEVIRI). As new satellite sensors—for example, the Himawari-8 Advanced Himawari Imager (AHI) and the Geostationary Operational Environmental Satellite Advanced Baseline Imager (ABI)—become available, there is a need to adjust the EUMETSAT RGB standard thresholds (i.e., recipes) to account for differences in spectral characteristics, spectral response, and atmospheric absorption in order to maintain an interpretation consistent with legacy composites. For the purpose of comparing RGB composites derived from nonoverlapping geostationary sensors, an adjustment technique was applied to the Suomi National Polar-Orbiting Partnership (Suomi-NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) to create an intermediate reference sensor (i.e., SEVIRI pr...