L4 - Satellites in Marine Science Flashcards
Give 5 points about the MaxWave Project
- Part of ESA
- ERS-1 and ERS-2
- Monitored the oceans for large waves
- 2004 reported 10 open ocean waves over 25m (freak waves)
- Variety of global locations
What is NWP?
Numerical Weather Prediction
What are the 2 types of satellite?
- Polar Orbital
2. Geostationary
What are Polar Orbital satellites?
Ones that have a circular orbit over the poles
What are Geostationary satellites?
Ones that have a fixed position and always look at the same place at the same time
Give 5 points about Polar Orbital satellites
- They are in low orbit (altitudes of 700-900km)
- Orbital period of 90-100 minutes
- Swaths up to 3000km wide
- Sensors and platforms vary
- Resolution depends on the sensor
Who controls USA satellites?
NOAA and NASA
What is POESS?
Polar Earth Satellite System
What is the satellite programme in Europe run by ESA?
MetOp
Give 3 points about Geostationary satellites
- Altitude of 35,000km above the equator
- Near global coverage
- Distortion near the poles (geosynchronised to be above the equator)
Give 4 applications of Infrared Sounders
- Forecasting
- SST
- Fish Migration
- Ice Edges & Extents
What do Infrared Sounders do?
Observe emissions from the atmosphere in the wave bands 3-15um and convert to temperature, water content etc.
What do Infrared Sounders give?
An accurate representation of the top few cm of the ocean
Give 2 limitations of Infrared Sounders
- Sensitive to SST and Clouds
2. Need Ground-Truthing
Give 3 points about Optical Sensors
- Observe emissions from the atmosphere in the visible spectrum
- Photograph of the Earth
- Cannot be used in darkness (need IR imagery)
Give 6 applications of Optical Sensors
- Clouds/Fog
- Coastal Erosion Management
- Shallow, Clearwater Hydrography
- Mapping Pollution/Dredging Plumes
- Ice Edges
- Shallow Water Habitat Mapping
What is derived wind data?
Wind observations derived from the motion of clouds and water vapour at different atmospheric levels because there aren’t any direct observations of wind from satellites
What is AVM?
Atmospheric Motion Vectors
What is ATSR?
Along Track Scanning Radiometer
What is SAR?
Synthetic Aperture Radar
What are Along Track Scanning Radiometers used for?
To give highly accurate, near global SST records
What is the accuracy of Along Track Scanning Radiometers?
+/- 0.3 Deg C
What do you need for Along Track Scanning Radiometers?
30-Year Running Means
What is Synthetic Aperture Radar used for?
Measuring surface roughness
Give 7 applications of Synthetic Aperture Radar
- Surface Waves and Swell
- Circulations
- Internal Waves
- Coastal Topography
- Upwelling/Fronts
- Coastal Watch
- Ice Extent/Habitat Loss
What is an Altimeter?
A sensor that orbits on Polar Orbital satellites and sends high frequency radar pulses which are used to calculate satellite to surface height
What is the name of the joint USA/European SLR programme?
Jason-2
What is SEAWIFS?
Sea viewing Wide Field of View Sensor – it is a satellite/colour optical sensor with 1.13km resolution
At what rate can SEAWIFS collect data compared to traditional sampling techniques?
1-minute can collect as much as traditional sampling for 10-years
Give 3 applications of SEAWIFS
- Identifying Phytoplankton Blooms
- Deriving Shallow Water Depths
- Coral Reef Research
Give 3 points above Microwave Sounding Data
- Derived Atmospheric Soundings are used
- Senses radiation from water vapour and CO2
- Looks at upper level temperature/humidity and wind fields
Give 10 issues associated with the use of satellites
- Need Ground-Truthing
- Attenuation
- Cloud Cover
- Darkness
- SAR quality reduces with poor sea state
- Satellite pass isn’t always where it is needed
- Satiability/calibrations?
- Platform/Sensor failure
- V.high costs
- Limited to the top levels of the oceans
Give 9 satellite applications/uses
- Modelling
- Ocean Winds
- Ocean Temperatures
- Ocean Colour
- Ozone/CO2 Monitoring
- Ice Coverage
- Derived Atmospheric Soundings
- Altimeter Sea Heights
- Visual Analysis
