280 likes | 424 Views
Environmental Application of Remote Sensing: CE 6900. Course Instructor: Dr . Faisal Hossain (Associate Prof.). Tennessee Technological University Department of Civil and Environmental Engineering. SOIL MOISTURE SATELLITES. By: Abebe Gebregiorgis. Outlines.
E N D
Environmental Application of Remote Sensing: CE 6900 Course Instructor: Dr . Faisal Hossain (Associate Prof.) Tennessee Technological University Department of Civil and Environmental Engineering
SOIL MOISTURE SATELLITES By: Abebe Gebregiorgis
Outlines • Soil Moisture Active and Passive Satellite (SMAP) – NASA • Introduction • Mission Imperative Overview • Scientific Objectives • Scientific Overview • Application Overview • Current status • Soil Moisture and Ocean Satellite (SMOS) – ESA • Mission Imperative Overview and Scientific Objectives • Scientific Overview • Application Overview • Current status • Summary
Introduction • SMAP - both active and passive sensors • L-band radiometer – (passive sensor ) • L-band radar – (active sensor) • Designed to provide • Global Soil moisture • Freeze/thaw
Mission • to provide global measurements of soil moisture and freeze/thaw state via L-band radar and radiometry so as to • Improve estimates of land surface evaporation, • Have good understanding of land-atmosphere water and energy exchange
Specific objectives • Understand processes that link the terrestrial water, energy and carbon cycles • Estimate global water and energy fluxes at the land surface • Enhance weather and climate forecast skill • Develop improved flood prediction and drought monitoring capabilities
Scientific Overview Artistic rendition of the SMAP spacecraft
Scientific overview … • Orbit • Orbit Altitude: 670 km (450 to 700 km) • Inclination: 98 degrees, sun-synchronous • Local Time of Ascending Node: 6 pm • SMAP will make measurements from a 6am/6pm sun-synchronous polar orbit
Scientific overview … • Configuration: Conically-scanning reflector • Diameter: 6 meters • Shared by both radar and radiometer
Scientific overview … • Configuration: • 1000 km wide swath • Scanning system: Along track scanning ???
SMAP Satellite’s swath path 1shows the initial path of the satellite
SMAP Satellite’s swath path 2shows the swath path illustrate the scanning pattern of the antenna
SMAP Satellite’s swath path 3shows the swath path with more extensive coverage
Data Products • Schematic representation of passive (left) and active (right) microwave interaction with soil and vegetation
Scientific overview … • Configuration: • Resolution: • 40 km radiometer • 1-3 km SAR (Synthetic Aperture Radar) • 10 km – combined product • Rotation rate: 14.6 RPM • Beam efficiency: 90%
Data Products • Soil Moisture • L-Band Radiometer (1.41 GHz) • Resolution = 40 km • L-Band Radar (1.26 GHz) • Resolution = 10 km • Freeze/Thaw • L-Band Radar (1.26 GHz) • Resolution 3 km
Data Products • Sampling duration • 6 am/ 6 pm • Revisit duration • Global = 3 days • Boreal = 2 days • Mission life • Minimum = 3 years
Application Overview • Hydrological Hazards Applications: • Drought and Flood • Ecosystem Services Applications • Agricultural Productivity • Weather Forecast Applications • Climate Prediction Applications • Human Health Applications Status SMAP launch is currently targeted for 2014
Introduction • European Space Agency (ESA) • The SMOS mission is a direct response to the current lack of global observations of soil moisture and ocean salinity • It objectives are to: • globally monitor surface soil moisture over land surfaces, • globally monitor surface salinity over the oceans, and • Improve the characterization of ice and snow covered surfaces.
Scientific overview • altitude of 755 km • view an area of almost 3000 km in diameter. Click here SMOS
Launch: 2009 • Duration: Minimum 3 years • Instrument: Microwave Imaging Radiometer • Instrument concept: Passive microwave • Frequency: L-band (21 cm -1.4 GHz) • Number of receivers: 69 • Spatial resolution: 35 km • Temporal resolution: 3 days revisit at Equator • Swath: 3000 km
Scientific application • Soil moisture • Ocean salinity Current Status
SMAP & SMOS • Do they have overlapping mission? • May new science opportunities arise if data from SMAP and SMOS mission are combined ? Facts: • SMOS will explore a potential technology but will provide only a 35 km resolution • SMAP will explore a potential technology and different instrument design and will provide a 10 km resolution • SMOS - ocean salinity, whereas SMAP -freeze/thaw
Evolution of SMOS & SMAP Day SMOS SMAPRadar-Radiometer ClimateApplications Weather Applications Week Resolved Temporal Scales Evolution of L-Band Sensing CarbonCycle Applications Radiometer Radar Month 100 km 10 km 1 km Resolved Spatial Scales
Thank You This material is extracted and compiled from http://smap.jpl.nasa.gov/ http://www.esa.int/esaLP