Solid Earth Timeline with a smattering of cryosphere technology

Transcription

1 Solid Earth Timeline with a smattering of cryosphere technology Muhammed Kabiru Hassan * Rebecca Boon Image from

2 SOLID EARTH SENSING TIMELINE LANDSAT 3 LANDSAT 6 (failed) LANDSAT 4 ICESA T 1 LANDSAT 1 STS-7(M OM S) LANDSAT 7 ICESA T LAGEOS 1 LANDSAT STS-11(MOMS) & LANDSAT LAGEOS EO LANDSAT GRACE, GRACE 2 & SPACE SHUTTLE ENDEAVOR (SRTM) FUTURE: LAGEOS 3 DESDynl

3 The Technology

4 Synthetic Aperture Radar Useful but not always satellite based SAR systems take advantage of the long-range propagation characteristics of radar signals and the complex information processing capability of modern digital electronics to provide high resolution imagery. Synthetic aperture radar complements photographic and other optical imaging capabilities because of the minimum constraints on time of day and atmospheric conditions and because of the unique responses of terrain and cultural targets to radar frequencies.

5 LIDAR Light Detection and Ranging (LIDAR) is a remote sensing system used to collect topographic data Measures properties of scattered light to determine range of object Much shorter wavelengths of the electromagnetic spectrum are used, typically in the ultraviolet, visible, or near infrared Lidar is highly sensitive to aerosols and cloud particles and has many applications in atmospheric research and meteorology [1]. Two types: micropulse lidar systems and high energy systems.

6 Altimeter Used to measure the altitude of an object above a fixed level uses advanced dual-band radar altimeters to measure height from a spacecraft. The two different wavelengths of radio waves used permit the altimeter to automatically correct for varying delays in the ionosphere delay may be caused by water vapor in the atmosphere. Other corrections are also required to account for the influence of electrons in the ionosphere and the dry air mass of the atmosphere. Modeling important

7 Radiometers A radiometer is a device for measuring the radiant flux (power) of electromagnetic radiation. Can comprise of detectors operating on any electromagnetic wavelength, e.g. spectroradiometer Radiometers detect and measure radiation as thermal (convert absorbed energy to a signal) and photodiode (photons absorbed at a constant response/quantum). A radiometer's characteristics are: spectral range spectral sensitivity angle of view directional response Examples are ASTER instrument on Terra

8 Spectrometers Found on multispectral scanners The variable measured is most often the light's intensity but could also be the polarization state. A spectrometer is used in spectroscopy for producing spectral lines and measuring their wavelengths and intensities to identify materials Chandrayaan-1 has moon mineralogy mapper M3 M3 is a state-of-the-art imaging spectrometer that will provide the first map of the entire lunar surface at high spatial and spectral resolution, revealing the minerals of which it is made

9 Satellite and Instrument Timeline

10 MOMS Modular Optoelectronic Multispectral Scanner Launched on Space Shuttle STS-7 in 1983 and STS-11 in 1984 Scanning system for airborne and spaceborne, geoscientific remote sensing applications. Developed by German Ministry for Research and Technology under contract from the German Aerospace Research Establishment (DLR). Instrumentation: modular arrangement of the CCD-sensor, electronics, optical lens system, and filters. This multispectral mode of MOMS enabled, among other uses, geologic mapping and mineral resources exploration. Resolution: 20x20m ground size from about a 300 km orbital altitude.

11 LAGEOS 1&2 Laser Geodynamics Satellites Passive vehicles covered with retroreflectors designed to reflect laser beams transmitted from ground stations. Goals: Provide an orbiting benchmark for geodynamical studies of the Earth. Determine the planet's geoid Determine tectonic plate movements associated with continental drift. LAGEOS 1 Built by NASA Launched in 1976 LAGEOS 2 Built by Italian Space Agency Launched in 1992 The LAGOS-1 Satellite from NASA

12 TOPEX/Poseidon TOPEX/Poseidon mission NASA and French Space Agency (CNES) Launched 1992 Mission: make highly accurate measurements of the dynamic components of ocean topography. Rationale: ocean topography reflects geoid determined by geographical variations in earth s gravity field. Tells us about mass distributiong of earth. Instrument: dual-frequency (Ku and C band) altimeter system 3-frequency microwave radiometer operates at 18,21 and 37 GHz to measure atmospheric water content and refraction index of atmosphere, which is used to calculate distance between altimeter and ocean surface.

13 EMTs/LANDSAT ETM+ (Enhanced Thematic Mapper Plus) part of The Landsat program Landsat 1 (originally named Earth Resources Technology Satellite 1) - launched July 23, 1972, terminated operations in 1978 Landsat 2 - launched January 22, 1975, terminated in 1981 Landsat 3 - launched March 5, 1978, terminated 1983 Landsat 4 - launched July 16, 1982, terminated 1993 Landsat 5 - launched March 1, 1984, still functioning. Landsat 6 - launched October 5, 1993, failed to reach orbit Landsat 7 - launched April 15, 1999, still functioning, but with faulty scan line corrector (May 2003) Landsat 7 data has eight spectral bands with spatial resolutions ranging from 15 to 60 meters.

14 This simulated true-color image of the island of Hawai'i was derived from data gathered by the Enhanced Thematic Mapper plus (ETM+) on the Landsat 7 satellite between 1999 and Photo from NASA

15 TERRA Terra is the main satellite of NASA s Earth Observing System. Launched on December 18, 1999 Scientific instruments: ASTER, CERES, MISR, MODIS, and MOPITT. We will focus on ASTER and MODIS.

16 ASTER Advanced Spaceborne Thermal Emission and Reflection Radiometer Built by NASA and Japan's Ministry of Economy Trade and Industry (METI) ASTER's three subsystems are the Visible and Near Infrared the Shortwave Infrared the Thermal Infrared Multispectral:14 bands, from the visible to the thermal infrared wavelengths Stereo viewing capability for digital elevation model creation

17 ASTER : Volcano Monitoring Lava flows are1-10km long, some up to 100km Central vent volcanic are km ASTER s 60x60km footprint and m/pixel (VNIR-SWIR- TIR) resolution scale captures most volcanoes 29 July 2001 summit eruption of Mt. Etna captured by ASTER in false color. Spatial resolution is 15 m/pixel. ASTER VNIR (Band 3), SWIR (Band 4), and TIR (Band 10) are blue, green, and red. _Examples/volcanology/default.htm

18 ASTER : Economic Geology High spatial resolution provide data that improve geologic mapping Right: Cuprite Mining District Nevada displayed using ASTER SWIR bands as a RGB composite. Area covered is 15 x 20 km. Red-pink : opalized rocks with kaolinite and/or alunite White area : Stonewall Playa Green areas : limestones Blue-gray areas : unaltered volcanics. xamples/geology/default.htm

19 ASTER : Byrd Glacier, Antarctica. Top : ASTER image mosaic Bottom : Change in ice flow speeds Contributed by Gordon Hamilton and Leigh Stearns (University of Maine). _data/05_application_examples/glacier /default.htm

20 MODIS Moderate Resolution Imaging Spectroradiometer (MODIS) Part of NASA's Earth Observing System (EOS) program Found on satellites Terra, launched December 18, 1999 (north south AM orbit) Aqua, launched May 4, 2002 (south north PM orbit) Earth s surface covered in 1 to 2 days, acquiring data in 36 spectral bands. Instrumentation: high radiometric sensitivity (12 bit) in 36 spectral bands ranging in wavelengths from 0.4 µm to 14.4 µm. measurements have spatial resolutions of 250 m (bands 1 and 2), 500 m (bands 3-7), and 1000 m (bands 8-36) National Snow and Ice Data Center uses MODIS to show snow and ice coverage.

21 ICESat I Ice, Cloud, and Land Elevation Satellite Instrumentation: Geoscience Laser Altimeter System (GLAS), a space-based LIDAR. GLAS combines a precision surface LIDAR with a sensitive dual-wavelength cloud and aerosol LIDAR. Global Positioning System (GPS) receiver star-tracker attitude determination system. Goal: Study ice sheet mass balance Launched 12 January Operates for one-month periods out of every three to six months in order to extend the time series of measurements, particularly for the ice sheets.

22 EO-1 Earth Observing-1 Part of NASA's Earth Observing System (EOS) program Launched November 21, 2000 Objectives: demonstrate new technologies and strategies for improved Earth observations. Instuments: ALI (Advanced Land Imager) Hyperion (Hyperspectral Instrument) LAC (Linear Etalon Imaging Spectral Array (LEISA) Atmospheric Corrector)

23 GRACE: Gravity Recovery and Climate Experiment Twin satellites launched 17 March 2002 Measurements of Earth's gravity field and Earth's water reservoirs, over land and ice Science: inter-satellite range change measurements Accelerometer GPS and attitude measurements from each satellite. Tectonic features are now resolved by GGM01S that were previously unobservable in gravity models derived from geodetic satellites alone. Above: Gravity anomalies from GGM01S reveal important geophysical features

24 Source: NASA Earth System Science Pathfinder Program.

25 GRACE-II GRACE-II is the follow-on mission to GRACE Microwave or Laser Ranging System Launched in 2002 Objective of the GRACE-II : Provide high-temporal-resolution gravity field measurements for the purpose of tracking large-scale water movement.

26 SRTM The Shuttle Radar Topography Mission (SRTM) Launched 2002 on Space Shuttle Endeavour 11 day mission Specially modified radar system obtained elevation data on a nearglobal scale to generate the most complete high-resolution digital topographic database of Earth. Technique: interferometry. two images are taken from different vantage points of the same area the slight difference in the two images allows scientists to determine the height of the surface Above: The SRTM instrument was made up of three sections, the main radar antenna, the mast, and the outboard radar antenna. From entoverview.html

27 Future Missions

28 LANDSAT NASA and the U.S. Geological Survey (USGS) are currently developing a plan for a follow-on mission to Landsat 7 set for 2011

29 ICESat-II NASA considering ICESat-II GLAS (Geoscience Laser Altimeter System) GPSP (Global Positioning System Payload) Goals: further study of polar ice changes and biomass/carbon in vegetation. Expected launch: 2015.

30 LAGEOS 3 Joint multinational program involving France, Germany, Great Britain, Italy, Spain and the United States. Goal: measure the Earth s gravitational magnetic dipole moment as predicted by Einstein's theory of general relativity.

31 DESDynl DESDynI: InSAR and LIDAR satellite Focus: surface deformation, ice sheet dynamics, and ecosystem structure InSAR- Interferometric Synthetic Aperture RADAR (Radio Detection And Ranging) L-band with multiple polarization LIDAR- Light Detection And Ranging operating in the infrared (~ 1064 nm) with ~ 25 m spatial resolution and 1 m vertical accuracy.