AA What role does the electromagnetic spectrum play in satellite imagery? Visible Light
Differences Among Infrared Regions Near IR- (0.7 - 1)microns 740- (3000-5200 K) Earth’s surface and above Mid IR 5 to (25-40) microns (92.5-140) to 740 K only above the atmosphere Far IR (25-40) to (200-350) microns (10.6-18.5) to (92.5-140) K only above the atmosphere
Satellite imagery is a special case of photography. Radiation bands in the electromagnetic spectrum that are reflected from the Earth’s surface back into space can be collected by satellite sensors and stored digitally. The most common electromagnetic bands used in satellite imagery are visible light, near infrared radiation (NIR), and infrared radiation (IR). Satellite Imagery-Remote Sensing
What different types of information do IR and visible wavelengths supply?
Differences between ground IR data, aerial data, and satellite data? Ease of data collection Data extent, records Spatial Resolution Temporal Resolution Spectral Resolution
Tradeoffs in Sensor Design To increase the signal to noise ratio, we can : Field of View Dwell time Width of spectral bands How do these changes affect the different resolutions?
Landsat 7 Program Temporal: 16 days Spectral: 4-8 bands Spatial: 30 m http://earthobservatory. nasa.gov/Features/Land sat/ Land cover and land cover change
MODIS ( on 2 satellites, Moderate Resolution Imaging Spectroradiometer) Temporal: Daily Spectral: 36 bands Spatial: 250-1000 m http://modis.gsfc.nasa.gov/about Global land cover and ocean RS Fire monitoring
IKONOS- commercial Temporal: On Demand Spectral: 4 bands, panchromatic Spatial: 1-4 m Local land cover http://www.satimagingcorp.com/gallery- ikonos.html
JASON (Active) Temporal: 10 days Spectral: NA (Active) Spatial: ~ 2 km http://ilrs.gsfc.nasa.gov/satellite_missions/list_of_sate llites/jas2_general.html Sea level
Sensor Platforms Pigeons, Planes, and Satellites Pigeons, planes, and satellites
How might scientists use IR data to study the earth’s surface? Kohrs, Infrared Image
How can satellite imagery be applied to climate change? Weather forecasting Storm tracking Ocean temperature monitoring Sea level changes Large scale land mass changes
Aerial Photography Works on the same principles as satellite imagery Altitude is less giving better resolution and more details. Used for change analysis, planning, natural resource management, and land use identification.
Student Activities Spectral Analysis-inquiry exploration Satellite Imagery-internet NC OneMap-data and imagery http://www.nconemap.com/ National Map-data and imagery http://nationalmap.gov/viewer.html
Summary Remote sensing allows us to observe and monitor the earth surface Features on the ground can be interpreted using spectral information Satellites have wide range of purposes