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A Remote Sensing Sampler. Typical reflectance spectra. Remote Sensing Applications Consultants - http://www.rsacl.co.uk. Even within a class of materials there are differences in spectral signatures. Nahum Gat (1998).
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Typical reflectance spectra Remote Sensing Applications Consultants - http://www.rsacl.co.uk
Even within a class of materials there are differences in spectral signatures Nahum Gat (1998)
Near surface remote sensing in Pinedale, Wyoming - sensor is seeing a combination of vegetation and soils and how that changes through the season NDVI = NIR – R/NIR + R (Prihodko, Chong, Steltzer and Shory, unpublished data)
Some sensors acquire two or three bands within the spectrum, and some acquire hundreds NASA LASP/Univeristy of Colorado, Boulder
Sensors operate at different spectral, spatial and temporal scales 1m – Quickbird http://www.spaceimaging.com 10m ~SPOT 30m ~TM 250m ~MODIS 500m ~MODIS 1Km ~AVHRR
Four Mile Fire, Boulder County, Colorado – September 2010 High-resolution (sub-meter) DigitalGlobe images
2000 1990 Greeley, Colorado GeoCover (GLCF 2005)
Landsat MSS August 15, 1973 Landsat TM June 23, 1990 Landsat ETM+ September 20, 2002 Landsat ETM+ June 27, 2006
MODIS images with statewide greenness standardized across years, showing declines due to killed trees, which appear red in the high resolution image.
Percent Ground Cover Vegetation Continuous Field (MODIS MOD44B) – 250m Hansen, M., R. DeFries, J.R. Townshend, M. Carroll, C. Dimiceli, and R. Sohlberg (2006), Vegetation Continuous Fields MOD44B, 2001 Percent Tree Cover, Collection 4, University of Maryland, College Park, Maryland, 2001.
Normalized Difference Vegetation Indices NDVI – AVHRR R. Boone, using AVHRR Pathfinder NDVI
Sea Surface Temperature, May 2001 - MODIS NASA Science Earth
City Lights (DMSP program) Nighttime Lights of the World: 1994-95 Christopher D. Elvidge http://sedac.ciesin.org/gpw-v2/presentations/ChrisElvidge/nightCD/world95.html
Nighttime Lights data also shows regions of high fire activity White – human settlement Green – gas flares Red – ephemeral lights (fires) Blue – fishing boats Nighttime Lights of the World: 1994-95 Christopher D. Elvidge http://sedac.ciesin.org/gpw-v2/presentations/ChrisElvidge/nightCD/world95.html
MODIS Burned Area Product (500m) Blue – July Green – January Red - June http://modis-fire.umd.edu/index.html
MODIS Active Fire Product – Four Mile Canyon Fire The MODIS instrument on NASA’s Aqua satellite captured this natural-color image of the fire at 2:40 p.m. local time on September 7, 2010. The red outline corresponds with the unusually high surface temperatures associated with an active fire. Credit: NASA/MODIS: http://www.nasa.gov/topics/earth/features/fourmile-canyon-fire.html http://modis-fire.umd.edu/Active_Fire_Products.html
EOS (Earth Observing System) AQUA satellite – AIRS (Atmospheric Infrared Sounder) http://airs.jpl.nasa.gov Variations in the height of a surface representing a constant value of water vapor during the summer and fall of 2005. This water vapor surface is highest in the tropics where vapor amounts are largest.
Shuttle Radar Topography Mission of 2000 More than 80% of the earth’s elevations measures 30 m resolution in US 90 m resolution elsewhere Galapágos Islands (Boone 2010)
MODIS Snow Cover – Colorado January 2007 image courtesy of NASA's Earth Observatory. http://modis-snow-ice.gsfc.nasa.gov/010707co.html http://modis-snow-ice.gsfc.nasa.gov/