Remote Sensing of Global Climate Change

Transcription

1 of Global Climate Change

2 2009 TECHNICAL STUFF... WHERE ON THE EARTH IS THAT??? Students should understand various geographic coordinate systems used to locate images, and how to translate these into distances HOW IN SPACE DID WE OBTAIN THAT??? Students should understand NASA s earth resources satellites, basic science objectives, orbits, sensor systems, and electro-magnetic spectrum s Interaction with the atmosphere and earth surface. HOW ON EARTH DID THAT PRETTY IMAGE COME FROM ONES AND ZEROS??? Students should understand the basics of digital image processing. APPLICATION STUFF... OBSERVABLE CONSEQUENCES OF CLIMATE CHANGE??? Retreat of GLACIERS shrinkage of ICE SHEETS Severe FOREST FIRES DESERTIFICATION CHANGING SEA LEVEL SEVERE natural disasters Changing ICE THICKNESS Slide 2 HUMAN CONTRIBUTORS TO CLIMATE CHANGE??? DEFORESTATION URBANIZATION / HEAT ISLAND MORE GREENHOUSE GAS NATURAL CONTRIBUTORS TO CLIMATE CHANGE??? MORE SUN OUTPUT MORE GREENHOUSE GAS ORBITAL PRESCESSION CYCLES

3 Mapping and Basics (hour one) Examples of Maps, coordinates, scales, measurements and proportions Aerial Photography... focal length and altitude ratios Electromagnetic spectrum... capturing and counting photons Converting data to visual images (RGB) Atmospheric Windows... absorption and scattering effects Passive and Active systems Sensor Resolution... spatial, spectral and temporal Getting the most from the data... digital signal enhancement of Global Climate Change (hour two) Earth Resource missions (currently operational) Sensor systems and characteristics Internet-accessible images and studies Slide3

4 Mapping and Basics Examples of discuss differences between in situ and remote sensing... at a distance electromagmetic radiation (sight) physical vibrations (sound) Instruments used for discuss how we capture and interpret remotely sensed data instruments used means for transmitting data interpretation of data Slide 4

5 Mapping and Basics Maps, coordinates, scales, measurements and proportions Discussion of maps, coordinate systems and scales English and metric scales Coordinate grids... Cartesian, Geographic, UTM Problem: determine coordinates of a feature on a map. Problem: determine dimensionless map scale Problem: convert a map measurement to a real distance Problem: proportion measurements from map to image Slide 5

6 Mapping and Basics Geographic Coordinate System Familiar Latitude and Longitude LATITUDE degrees north and south of Equator Latitude distance per degree is constant LONGITUDE degrees east and west of Prime Meridian Longitude distance per degree is constant Universal Transverse Mercator (UTM) Distances in METERS north of Equator and north of South Pole Southern Hemisphere starts at 10,000,000 m Distances in METERS east of false baseline 500,000 m EASTING at center of ZONE 60 Zones worldwide, each 6-degrees wide Right-angle system allows direct computation of distances in zone Slide 6

7 Mapping and Basics Aerial Photography... focal length and altitude ratios Discussion of focal length, film/sensor dimensions and relationship to distances on the ground Diagram showing focal ratios. Problem: determine ground frame width of an aerial photo (use examples of 9x9 negatives) Problem: determine altitude needed for a scaled photo (use examples of 9x9 negatives) Discussion of proportionality relationships and scale ratios for digital sensor systems with the PIXEL as the smallest unit of data capture Slide 7

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9 Mapping and Basics Electromagnetic spectrum... capturing and counting photons Discussion of energy versus wavelength; gamma, x-ray, UV, visible, IR, and radio waves. E-M Spectrum Diagrams Discussion of analog (film) and digital data collection; multi-spectral versus frequency-specific data capture Discussion of visualizations of data, and false color images Color Infrared RGB assignments Slide 9

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11 Mapping and Basics Absorption and scattering effects... Mie scattering, Raleigh scattering, non-selective scattering absorption Relationship between wavelength and particle/molecule size Atmospheric Windows... Restricts wavelengths available for remote sensing use Visible, Near IR, Far (thermal IR), Radio Function of atmospheric composition and density Slide 11

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13 Mapping and Basics Passive Sensor Systems... Discuss energy sources for passive systems Discuss energy levels (radiometric resolution) Affects time available for data acquisition Affected by atmospheric effects (moisture, cloud cover) Active Sensor Systems... RADAR LIDAR Can choose penetrating wavelengths to see through clouds Requires higher power level onboard sensor platform Slide 13

14 Mapping and Basics Sensor Resolutions... Big tradeoff in mission design. Increasing one usual decreases another Juggling diagram Discuss the various sensor resolutions and how they vary Spatial... Limiting object size Spectral... Frequency discrimination Radiometric... range of values, gray levels Temporal... Revisit frequency Diagrams with digital sensor arrays and pixels Scanner Systems... Cross Track... Along Track Diagram with scanner types Orbits and Swaths... Cross Track... Along Track Diagram with orbital paths Slide 14

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17 Image Type Pixel Value Color Levels 8-bit image 2 8 = bit image 24-bit image 2 16 = = bit image 4 gray levels 8-bit image 256 gray levels Slide 17

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20 Mapping and Basics Getting the most from the data... digital signal enhancement Diagrams and Images for stretch example and false color Problem: determine min and max values for 2-bit and 8-bit processors Problem: determine gray levels for 6-bit processor Problem: what wavelengths are usually combined for Color Infra-Red images? Discuss comparison with Ansel Adams ZONE SYSTEM for black and white film photography Slide 20

21 Linear Contrast Stretch R-G-B False Color Image Band 1 Band 2 Band 3 Slide 21

22 Mapping and Basics Canada Center For Fundamentals of Tutorial Digital Images and Digital Analysis Techniques Tutorial Glossary of Terms NASA Tutorial Slide 22

23 Earth and Climate Change What s the next part of this presentation??? NASA / ESA Earth Resources Satellite Missions Where to find this information Sensor Systems carried onboard Where to find this information Images from Internet-accessible NASA collections Where to find this information Slide 23

24 and Climate Change INTERNET PORTALS NASA Earth Satellite Programs Earth Observing Sysem Ocean Surface Topography from Space Satellites IMAGE Collections Coaches Institute This Coaches Institute presentation will be posted on NCSO webpage along with the 2007 and 2008 State Mars RS Test (w/ answers, explanations and internet resource links) Slide 24

25 Earth Observing System LANDSAT 7 QuickSCAT TERRA ACRIMSAT JASON-1 AQUA SEAWINDS ICESat SORCE AURA OSTM Slide 25

26 AQUA AIRS (Atmospheric Infrared Sounder) AMSR (Advanced Microwave Scanning Radiometer) AMSU-A (Advanced Microwave Sounding Unit-A) CERES (Clouds and Earth's Radiant Energy System) HSB (Humidity Sounder for Brazil) MODIS (Moderate-Resolution Imaging Spectroradiometer ) Slide 26

27 TERRA ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) CERES (Clouds and Earth's Radiant Energy System) MISR (Multiangle Imaging Spectroradiometer) MODIS (Moderate-Resolution Imaging Spectroradiometer) MOPITT (Measurements of Pollution in the Troposphere) Slide 27

28 MODIS... (Moderate-Resolution Imaging Spectroradiometer) ASTER... (Advanced Spaceborne Thermal Emission and Reflection Radiometer) CERES... (Clouds and Earth's Radiant Energy System) MISR... (Multiangle Imaging Spectroradiometer) MOPITT... (Measurements of Pollution in the Troposphere) SENSORS FLOWN ON TERRA Slide 28

29 ETM+ (Enhanced Thematic Mapper Plus) LANDSAT Slide 29

30 Satellite Altimetry Slide 30

31 TOPEX-POSEIDON OSTM-JASON 1 & Slide 31

32 Orbital Information from heavens-above.com Orbit: 645km, 40 inclination Perigee Height: 605 km Apogee Height: 640 km Slide 32

33 Orbital Information from heavens-above.com Orbit: 701 x 703 km, 98.2 Polar, Sun-synchronous Slide 33

34 Image Collection Portal... October 24 25, 2007 Slide 34

35 Earth Observatory Features... October 24 25, 2007 Slide 35

36 Earth Observatory Features October 24 25, 2007 Slide 36

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