What is satellite altimetry?
Satellite radar altimetry measures the time taken by a radar pulse to travel from the satellite antenna to the surface and back to the satellite receiver. This measurement yields a wealth of information that can be used for a wide range of applications – in particular, for understanding sea-level rise.
What is wide swath altimetry?
Pasadena, CA 91109. Abstract-The Wide Swath Ocean Altimeter (WSOA) is a recently proposed interferometric instrument that would provide nearly complete global ocean topography measurements from a single platform.
What method of measuring elevation uses radar from a satellite?
Radar altimetry measures the two-way travel time of a radar pulse between the satellite antenna and the Earth’s surface at the nadir of the spacecraft. This measurement is performed through the recording of the pulse bounced back by the reflecting facets within the altimeter footprint.
When was satellite altimetry invented?
The development of satellite altimetry technology has been a constant effort since the 1970s. The first altimeter that aimed to measure the shape of the Earth was on-board the satellite Skylab in 1973.
What is meant by altimetry?
altimetry. / (ælˈtɪmɪtrɪ) / noun. the science of measuring altitudes, as with an altimeter.
What is altimetry How does it work?
The altimeter measures the height of an aircraft above a fixed level. The instrument senses this by taking the ambient air pressure from the static port. As the aircraft goes up, the pressure inside the case decreases and the bellows expand. The opposite happens as the aircraft descends.
How does a satellite altimeter work?
Satellite radar altimeters measure the ocean surface height (sea level) by measuring the time it takes a radar pulse to make a round-trip from the satellite to the sea surface and back. Seventy percent of Earth’s surface topography is under the oceans, and cannot be directly sensed by lasers or radars.
How does a weather satellite altimeter work?
The altimetry satellites transfer radar signals down to the surface of the water over oceans, seas and lakes and receive their reflections. Since the velocity of the signal is known, the distance between the satellite and the water surface can be estimated by measuring the signal travel time.
Why do altimetry is used in oceanography?
The primary contribution of satellite altimetry to satellite oceanography has been to: Improve the knowledge of ocean tides and develop global tide models. Monitor the variation of global mean sea level and its relationship to changes in ocean mass and heat content.
What is a jettisoned?
transitive verb. 1 : to get rid of as superfluous or encumbering : omit or forgo as part of a plan or as the result of some other decision must be prepared to jettison many romantic notions— Christopher Catling.
What does an altimeter calculate?
An altimeter is a device that measures altitude—a location’s distance above sea level. Most altimeters are barometric, meaning they measure altitude by calculating the location’s air pressure. They determine altitude by measuring air pressure. As altitude increases, air pressure decreases.
How accurate are altimeters?
With proper calibration, the barometric altimeter of an outdoor watch or handheld will report elevation readings ranging from -2,000 to 30,000 feet with an accuracy of +/-50 feet. Elevation values greater than 30,000 feet can be generated, but may not be accurate due to environmental factors.