What does scatterometer measure?
Scatterometers are active remote sensing instruments for deriving wind direction and speed from the roughness of the sea. They are used by low Earth orbiting satellites and act like radars: they transmit electromagnetic pulses and detect the backscattered signals.
How scatterometer works?
A radar scatterometer operates by transmitting a pulse of microwave energy towards the Earth’s surface and measuring the reflected energy. A separate measurement of the noise-only power is made and subtracted from the signal+noise measurement to determine the backscatter signal power.
What is advanced scatterometer?
ESA / Applications / Observing the Earth / Meteorological missions / MetOp. The Advanced Scatterometer (ASCAT) is one of the new-generation European instruments carried on MetOp and will be used to determine information about the wind for use primarily in weather forecasting and climate research.
What is the satellite Nscat used for?
NSCAT provides continuous measurements of ocean surface wind speeds from space, which will help meteorologists better predict the behavior of storms. Data like these are being used by the National Weather Service, an agency of the National Oceanic and Atomospheric Administration in their global forecast models.
What is Ascat weather?
The Advanced Scatterometer (ASCAT) winds products are processed by NOAA/NESDIS utilizing measurements from the scatterometer instrument aboard the EUMETSAT Metop satellites. The instrument uses radar to measure backscatter to determine speed and direction of winds over the surface of the oceans.
How has satellite technology helped the study of oceanography?
Satellites also provide information about the color of the ocean. For example, color data helps researchers determine the impact of floods along the coast, detect river plumes, and locate blooms of harmful algae that can contaminate shellfish and kill other fish and marine mammals.
How do you observe wind?
The easiest way to observe true wind direction is by looking at the clouds. Typically if the clouds are coming from the north, then it’s a north wind. If they’re coming from the west, it’s a west wind, etc.
How do you judge wind speed?
- Estimating Wind Speeds with Visual Clues. Beaufort.
- 0 Calm. Calm Calm wind.
- 1 Light Air. 1 to 3 mph Direction of wind shown by smoke drift, not by wind vanes.
- 2 Light Breeze. 4 to 7 mph Wind felt on face.
- 3 Gentle. Breeze 8 to 12 mph Leaves and small twigs in constant motion.
- 4 Moderate.
- 5 Fresh Breeze 19 to 24 mph.
- 6 Strong.
How do you read wind strength?
Gauge wind speed.
- A small, open circle indicates that the winds are calm.
- A single short line (half line) or “feather” represents 5 knots (5.75 mph) of wind speed.
- A single long line (full line) or “feather” represents 10 knots (11.50 mph).
What are the 3 technologies for studying the ocean floor?
List three technologies for studying the ocean floor, and explain how they are used. Sonar, Geosat, and underwater vessels; sonar is used to determine the ocean’s depth by sending sound pulses from a ship down into the ocean.
What wind speed makes white caps?
Whitecaps: aka “White Horses” are breaking wave crests that can be observed in windy conditions. White caps begin to appear at 8-10 knots, and are more frequent in 15 knots. Units of speed: abbrev “mph”, are a more common unit of speed in the US.
Which technology has allowed scientists to accurately map the ocean floor?
Using Sonar. The first modern breakthrough in sea floor mapping came with the use of underwater sound projectors, called “sonar”, which was first used in World War I.
What is scatterometry and how does it work?
Scatterometer instruments are very precisely calibrated in order to make accurate backscatter measurements. The primary application of spaceborne scatterometry has been measurements of near-surface winds over the ocean. Such instruments are known as wind scatterometers.
How does a scatterometer work on a satellite?
A scatterometer fitted to a satellite in low orbit operates over a wide swath, typically around 500 km. Resolution is between 25 and 50 km. Wind speed can be estimated with an accuracy of 2 m/s (mean square error), and direction with 20° accuracy. For each sea area of the size of a resolution cell, the radar supplies the following parameters:
What is a radar scatterometer used for?
Radar scatterometers use radio or microwaves to determine the normalized radar cross section (σ 0, “sigma zero” or “sigma naught”) of a surface. They are often mounted on weather satellites to find wind speed and direction, and are used in industries to analyze the roughness of surfaces. Airport scatterometer (or diffusometer).
What happened to the NASA Scatterometer?
The next full-time scatterometer was the NASA scatterometer (NSCAT), was flown on the ill-fated Japanese Midori satellite. NSCAT functioned from August 1996 to June 1997, when Midori suffered a catastrophic power loss.