Geography 372 Fall 2003November 4, Remote Sensing of the Land Surface: High Spatial Resolution Michael D. King & Compton J. Tucker Outline  Land remote sensing at high spatial resolution  Satellite sensors enabling remote sensing of land cover at high spatial resolution –Landsat RBV, MSS, TM, ETM+ –Spot HRV –Terra ASTER  Orbital characteristics  Instrument characteristics –Spacecraft, spatial resolution, swath width, sensor characteristics, and unique characteristics  Land properties as observed by Landsat and ASTER

Geography 372 Fall 2003November 4, Characteristics of Landsat Missions

Geography 372 Fall 2003November 4, The orbital period of a satellite around a planet is given by where  0 = orbital period (sec) R p =planet radius (6380 km for Earth) H=orbit altitude above planet’s surface (km) g s =acceleration due to gravity ( km s -2 for Earth) Definition of Orbital Period of a Satellite

Geography 372 Fall 2003November 4, Landsat-1, -2, and -3 Observatory Configuration Solar array Multispectral Scanner (MSS) Return Beam Vidicon (RBV) cameras Data collection antenna

Geography 372 Fall 2003November 4, Spectral Sensitivity of the Four Landsat MSS Bands  Bands compared with the spectral sensitivity of the three emulsion layers used in color and color infrared film

Geography 372 Fall 2003November 4, Landsat MSS Operating Configuration

Geography 372 Fall 2003November 4, Ground Resolution Cell Size versus MSS Pixel Size

Geography 372 Fall 2003November 4, Landsat 5 TM EO-1 Hyperion Landsat 7 ETM+ EO-1 ALI Green Vegetation Senescent vegetation Bare soil Band 2 Band 3 Band 4 Band 5Band 7 Band 1

Geography 372 Fall 2003November 4, Satellite systems and sensors

Geography 372 Fall 2003November 4, Sun-Synchronous Orbit of Landsat-4 and -5

Geography 372 Fall 2003November 4, Successful Launch

Geography 372 Fall 2003November 4,

Geography 372 Fall 2003November 4, Landsat 7 Swathing Pattern

Geography 372 Fall 2003November 4, Swath Progression Pattern

Geography 372 Fall 2003November 4, Landsat-4 and -5 Observatory Configuration High gain antenna Multispectral Scanner (MSS) Solar array Thematic Mapper (TM) S-band antenna

Geography 372 Fall 2003November 4, Thematic Mapper Optical Path and Projection of Detector IFOVs on the Earth’s Surface

Geography 372 Fall 2003November 4, Schematic of TM Scan Line Correction Process (b) Correction for satellite motion (a) Uncompensated scan lines (c) Compensated scan lines

Geography 372 Fall 2003November 4,

Geography 372 Fall 2003November 4, Side-Lap Composting, no interpolation

Geography 372 Fall 2003November 4, Side-Lap Composting, no interpolation

Geography 372 Fall 2003November 4, Before After Multi-pass compositing, no Interpolation

Geography 372 Fall 2003November 4, Landsat’s Bands  Landsat collects monochrome images in each band by measuring radiance & reflectance in each channel. When viewed individually, these images appear as shades of gray

Geography 372 Fall 2003November 4,  The human eye is not sensitive to ultraviolet or infrared light –To build a composite image from remote sensing data that makes sense to our eyes, we must use colors from the visible portion of the EM spectrum— red, green, and blue Color Composites

Geography 372 Fall 2003November 4,  This image was produced using the red, green, & blue bands from Landsat’s Thematic Mapper –Note the washed out appearance of the landscape due to atmospheric effects ‘True Color’ Landsat TM Image R=0.66 µm G=0.56 µm B=0.48 µm

Geography 372 Fall 2003November 4, “False Color” Landsat Image  These images were produced using near-infrared, red, and green bands –Notice how vegetation is more clearly distinguished from nonvegetation Channels 4, 3, 2Channels 5, 4, 2

Geography 372 Fall 2003November 4, San Francisco Onion Skin Animation

Geography 372 Fall 2003November 4, Landsat 7 Launched April 15, 1999

Geography 372 Fall 2003November 4, Enhanced Thematic Mapper Plus (ETM+)  NASA & USGS, Landsat 7 –launched April 15, 1999 –705 km polar orbit, descending (10:00 a.m.)  Sensor Characteristics –7 spectral bands ranging from 0.48 to 11.5 µm –1 panchromatic band ( µm) –cross-track scan mirror with 185 km swath width –Spatial resolutions: »15 m (panchromatic) »30 m (spectral) –Calibration: »5% reflectance accuracy »1% thermal IR accuracy »onboard lamps, blackbody, and shutter »solar diffuser

Geography 372 Fall 2003November 4, Thematic Mapper Optical Path and Projection of Detector IFOVs on the Earth’s Surface

Geography 372 Fall 2003November 4, Landsat 7 Goals & Objectives  Land use and land cover change –Agricultural evaluations, forest management inventories, water resource estimates, coastal zone appraisals –Growth patterns of urban development, Spring run-off contaminants in lakes, land use in tropical rainforests, health of temperate conical forests, mapping wildfire hazards in Yosemite  Vegetation patterns –Annual cycle of vegetation dynamics, drought stress, and flooding –Dune reactivation in the US Great Plains, precision farming and land management  Glaciers and snow cover –Growth and retreat –Gradual changes in the Antarctic ice sheet  Geological surveys –Volcanic hazards and lava lakes

Geography 372 Fall 2003November 4, Chesapeake & Delaware Bays R=0.66 µm G=0.56 µm B=0.48 µm Baltimore Washington May 28, 1999

Geography 372 Fall 2003November 4, Benefits of Landsat 7 over other Missions  Mission Continuity –Spanning 25 years of multispectral imaging of the Earth’s surface, starting in 1972  Global Survey Mission –Approximately one quarter of the Earth’s landmass is imaged every 16 days »Every landmass will have seasonal coverage  Affordable Data Products –Landsat 7 data products are available from the EROS Data Center »Prices dropped from approximately $5,000 (Landsat’s 4 & 5) to $600 (Landsat 7) per scene

Geography 372 Fall 2003November 4, Washington, DC Landsat 5 Infrared band Landsat 7 panchromatic band

Geography 372 Fall 2003November 4, Washington, DC Detail Landsat 5 Infrared band Landsat 7 panchromatic band

Geography 372 Fall 2003November 4, Phoenix Development and Growth: Multispectral Scanner (MSS)

Geography 372 Fall 2003November 4, San Francisco Bay from Landsat 7 R=0.66 µm G=0.56 µm B=0.48 µm Golden Gate Bridge Bay Bridge Oakland Airport

Geography 372 Fall 2003November 4, Cape Canaveral R=0.66 µm G=0.56 µm B=0.48 µm

Geography 372 Fall 2003November 4, Flood of the Mississippi River in 1993 Before the floods After the floods Landsat 5 TM

Geography 372 Fall 2003November 4, Flood of the Limpopo River in Mozambique  The Limpopo River in Mozambique before and after the flooding from Cyclone Eline  About 700 people were killed and thousands were displaced by this event August 22, 1999 March 2, 2000 Landsat 7 ETM+

Geography 372 Fall 2003November 4, Cape Town & the Western Cape

Geography 372 Fall 2003November 4, Landsat 7 Data Archived during First 400 Days of Operation

Geography 372 Fall 2003November 4, Bolivia from Landsat: Thematic Mapper R=2.21 µm G=0.83 µm B=0.56 µm Colorado College Garden of the Gods Country Club