Satellite Remote Sensing: Earth System Observations

Transcription

1 Satellite Remote Sensing: Earth System Observations Land surface Water Atmosphere Climate Ecosystems 1

2 EOS (Earth Observing System) Develop an understanding of the total Earth system, and the effects of natural and human-induced changes on the global environment Expand scientific knowledge of the Earth system using capabilities from the vantage points of space, aircraft, and in situ platforms Disseminate information about the Earth system Mission objectives Acquire and assemble a global database emphasizing remote sensing measurements from space over a decade or more Improve predictive models of the Earth system 2

3 Multispectral Digital Image Multispectral Digital Image Spatial Resolution (Pixel size) Spectral Resolution (Bands) 3

4 QuikScat Terra Landsat / LDCM Jason-1 Aura SAGE III SORCE ICESat Aqua Landsat represents the world's longest continuously acquired collection of space-based land remote sensing data. It is considered the unique national assets. The first Landsat satellite was launched in 1972; the most recent, Landsat 8, was launched on February 11, The instruments on the Landsat satellites have acquired millions of images. The images, archived in the United States and at Landsat receiving stations around the world, are a unique resource for global change research and applications in agriculture, geology, forestry, regional planning, education and national security. 4

5 Landsat Missions Landsat 1 (07/12/ /06/1978) - RBV, MSS (80m) Landsat 2 (01/22/ /27/1983) - RBV, MSS (80m) Landsat 3 (03/05/ /07/1983) - RBV, MSS (80m) Landsat 4 (07/16/ ) - MSS, TM (30m, 120m TIR) Landsat 5 (03/01/ ) - MSS, TM (30m, 120m TIR) Landsat 6 (10/05/1993): ETM Landsat 7 (04/23/ ) - ETM+ (30m, 60m TIR, 15m Pan) Landsat 8 (February 11, 2013) OIL (30m, 15m Pan) Landsat 8 (February 11, 2013) TIRS (100m) ETM+: Enhanced Thematic Mapper Plus MSS: Multispectral Scanner OLI: Operational Land Imager Pan: Panchromatic RBV: Return Beam Vidicon Camera TIR: Thermal Infrared TIRS: Thermal Infrared Sensor TM: Thematic Mapper Spectral Cover of Landsat Sensors Band 1: m (blue). Provide increased penetration of water bodies, as well as supporting analysis of land use, soil, and vegetation characteristics. Band 2: m (green). This band spans the region between the blue and red chlorophyll absorption bands and therefore corresponds to the green reflectance of healthy vegetation. Band 3: m (red). This is the red chlorophyll absorption band of healthy green vegetation and represents one of the most important bands for vegetation discrimination. 5

6 Spectral Cover of Landsat Sensors Band 4: m (reflective infrared). This band is responsive to the amount of vegetation biomass present in the scene. It is useful for crop identification and emphasizes soil-crop and land-water contrasts. Band 5: m (mid-infrared) This band is sensitive to the amount of moisture in plants and therefore useful in crop draught and in plant vigor studies. Band 6: m (thermal infrared) This band measures the amount of infrared radiant flux emitted from surface. Band 7: m (mid-infrared) This is an important band for the discrimination of geologic rock formation. It is effective in identifying zones of hydrothermal alteration in rocks. Different surface types such as water, bare ground or vegetation reflects radiation differently in various channels. The radiation reflected as a function of the wavelength is called the spectral signature of the surface 6

7 Landsat-7 ETM+ Data of Providence Area Landsat-7 Panchromatic Data (15 m) Landsat-7 ETM+ Data (30 m), Bands 3, 2, 1 in RGB Landsat-7 ETM+ Data (30 m), Bands 4, 3, 2 in RGB Landsat-7 ETM+ Data (30 m), Bands 4, 5, 3 in RGB Landsat Data Continuity Mission (LDCM) Landsat-8 LDCM Observatory (OLI, TIRS) Mission Overview TDRSS LDCM Orbit 705 km circular sun sync, 10am DNLT 16 day repeat X band Stored Science RT+PB or Mbps Alaska Ground Station Gilmore, AK X band RT Broadcast 384 Mbps S-band CMD uplink 1 or 32 kbps S-band RT downlink 32 kbps S-band combined Stored & RT TLM downlink 1 Mbps Representative IC Canada Landsat Ground Station Sioux Falls, SD NASA GN Wallops Island, VA 7

8 Landsat-8 and Sensors: Provide continuity in the multi-decadal Landsat land surface observations to study, predict, and understand the consequences of land surface dynamics Land cover/use change Human settlement and population Ecosystem dynamics Landscape scale carbon stocks Resource management/societal needs Spectral Resolution ( m) Multispectral Scanner (MSS) Landsat (green) (red) (NIR) (NIR) Thematic Mapper (TM) Landsat 4 & (B) (G) (R) (NIR) (MIR) (TIR) (MIR) Enhanced Thematic Mapper Plus (ETM+) Landsat (Pan) Operational Land Imager (OLI) / Thermal Infrared Sensor (TIRS) Landsat (Pan) (TIRS) (TIRS) Spatial Resolution (meter) 79 x x x 120 (TIR) 15 x 15 (Pan) 30 x x 60 (TIR) 15 x 15 (Pan) 30 x x 100 (TIRS) Temporal Resolution (revisit days) 18 (Landsat 1,2,3)

9 Landsat Images of the World Search the data? 9

10 Rhode Island: Path 12/Row 31 Example: Searching of Landsat 8 images Footprint Quick look Image Data search example: Data type: Landsat 8 OLI/TIRS Location: Providence, RI Time period: , Cloud cover: < 10%, 10

11 Example: Searching of Landsat 8 images Footprint Quick look Image Data search example: Metadata Table Format Metadata FGDC Format FGDC (Federal Geographic Data Committee) Example: Searching of Landsat 8 images Footprint Quick look Image Data search example: Metadata Table Format Metadata FGDC Format FGDC (Federal Geographic Data Committee) 11

12 Footprint Quick look Image Data search example: Data type: EO-1 ALI, Location: California, USA Time period: Cloud cover: < 10%, Data search example: Metadata Table Format Metadata FGDC Format FGDC (Federal Geographic Data Committee) 12

13 Data search example: Metadata Table Format Metadata FGDC Format FGDC (Federal Geographic Data Committee) 13