Please join the University of Denver Department of Geography and the Environment as they welcome Dr. Tilottama Ghosh, Research Associate, Earth Observation Group, Payne Institute for Public Policy, presenting Earth Observations Group’s Data Gems from the Night on Thursday, February 23, 2023 from 4:00pm – 5:00pm MT at the University of Denver.  

The history of satellite remote sensing using nighttime lights can be traced back to the U.S. Airforce Defense Meteorological Satellite Program (DMSP), which began flying polar orbiting satellites in the 1970’s. The Operational Linescan System (OLS), onboard the DMSP, is an oscillating scan radiometer with low-light visible and thermal infrared imaging capabilities which first flew on DMSP satellites in 1976. At night the OLS uses a Photo Multiplier Tube (PMT) to intensify the visible band signal. The purpose of this intensification is to observe moonlit clouds. The light intensification enables observation of faint sources of visible- near infrared emissions present at night on the earth’s surface including cities, towns, villages, gas flares, heavily lit fishing boats and fires. In 1992, NOAA established a digital archive for DMSP data at the National Geophysical Data Center in Boulder, Colorado. The Earth Observation Group (EOG) was formed in 1994 and since then has dedicated its efforts to making global nighttime light data products for use by the scientific community and policy makers. Many of the inadequacies of DMSP data were addressed with the NASA/NOAA Visible Infrared Imaging Radiometer Suite (VIIRS) day/night band (DNB), which opened a new era in nighttime light studies. EOG continues to produce the daily, monthly, and annual DNB VIIRS Nightlight (VNL) composites. Besides VNL, the other two global products which EOG generates are – VIIRS Nightfire (VNF), which are multispectral detections of fire, flares, and other IR emitters, and VIIRS Boat Detection (VBD), which are offshore detection of lights based on type and intensity.

Wine and Cheese following Colloquium at 5:15pm.