Satellites have already revolutionized oceanography, and soon they will do the same for hydrology -- the study of water on land. The French/U.S. Surface Water and Ocean Topography (SWOT) mission will be at the forefront, carrying an innovative interferometer dubbed KaRin that marks a break with today's technologies.

dam you notes that these changes show the value the world scientific community places on the ocean altimetry program. "The measurement is so important, and the technology is fully demonstrated," he said. "In the long haul, ocean altimetry is an international commitment."

Abstract

Jason, the successor to the TOPEX/POSEIDON (T/P) mission, has been designed to continue seamlessly the decade-long altimetric sea level record initiated by T/P. Intersatellite calibration has determined the relative bias to an accuracy of 1.6 mm rms. Tide gauge calibration of the T/P record during its original mission shows a drift of −0.1 ± 0.4 mm/year. The tide gauge calibration of 20 months of nominal Jason data indicates a drift of −5.7 ± 1.0 mm/year, which may be attributable to errors in the orbit ephemeris and the Jason Microwave Radiometer. The analysis of T/P and Jason altimeter data over the past decade has resulted in a determination of global mean sea level change of +2.8 ± 0.4 mm/year.

Abstract

TOPEX/POSEIDON is the first space mission specifically designed and conducted for studying the circulation of the world's oceans. The mission is jointly conducted by the United States and France. A state-of-the-art radar altimetry system is used to measure the precise height of sea level, from which information on the ocean circulation is obtained. The satellite, launched on August 10, 1992, has been making observations of the global oceans with unprecedented accuracy since late September 1992. To meet the stringent measurement accuracy required for ocean circulation studies, a number of innovative improvements have been made to the mission design, including the first dual-frequency space-borne radar altimeter capable of retrieving the ionospheric delay of the radar signal, a three-frequency microwave radiometer for retrieving the signal delay caused by the water vapor in the troposphere, an optimal model of the Earth's gravity field and multiple satellite tracking systems for precision orbit determination. Additionally, the satellite also carries two experimental instruments to demonstrate new technologies: a single-frequency solid-state altimeter for the technology of low-power, low-weight altimeter and a Global Positioning System receiver for continuous, precise satellite tracking. The performance of the mission's measurement system has been tested by numerous verification studies. The results indicate that the root-sum-square accuracy of a single-pass sea level measurement is 4.7 cm for the TOPEX system and 5.1 cm for the POSEIDON system; both are more than a factor of 2 better than the requirement of 13.7 cm. This global data set is being analyzed by an international team of 200 scientists for improved understanding of the global ocean circulation as well as the ocean tides, geodesy, and geodynamics, and ocean wind and waves. The mission is designed to last for at least 3 years with a possible extension to 6 years. The multiyear global data set will go a long way toward understanding the ocean circulation and its variability in relation to climate change. A summary of the mission's systems and their performance as well as the mission's science team is presented in the paper.

Abstract

Using altimetry data of the Topex/Poseidon satellite available since early 1993, we show that the eastern Mediterranean sea level has been continuously rising during 1993–1999, at a rate up to 20 mm/yr southeast of Crete. Sea level rise is also observed in the Algerian-Provencal basin as well as in the Tyrrhenian and Adriatic seas. The north Ionian sea, on the other hand, shows an opposite trend, i.e., a sea level drop during the past seven years. Sea surface temperature trends are strongly correlated to sea level trends, indicating that at least part of the observed sea level change has a thermal origin. The recent Mediterranean sea level rise observed by Topex/Poseidon may be related to the warming trends reported from hydrographic cruises in the intermediate and deep waters of the eastern basin since the early 1990s, and of the western basin since the 1960s.

. . .ushered in a new era of oceanography with the first highly accurate, global measurements of sea levels. That mission and its three successors, all named Jason, have continuously mapped global ocean currents and tides; opened our eyes to the global reach of El Niño and other climate events; created a quarter-century-long, extraordinarily precise record of global and regional sea level rise; and enabled improved forecasts of extreme weather events such as hurricanes, floods and droughts.

More than 90 percent of the heat from global warming is stored in the ocean, which means oceans are key players in global climate. Heat causes ocean water to expand, adding to sea level rise. Measuring both long-term sea level trends and the shape of the ocean surface related to currents, Topex-Poseidon and the Jason series provide two basic ingredients for understanding the ocean's role in global climate variations.

Among Topex-Poseidon's early achievements was recording the full extent of a record El Niño in 1997 and the succeeding La Niña in 1999. Darker colors are sea levels lower than normal, lighter and white colors are higher than normal. Credit: NASA/JPL-Caltech.

For decades, scientists could not predict how El Niño and other year-to-year ocean variations changed regional weather. That was partly because, using only ships and buoys, they couldn't observe the genesis and growth of these changes far out in the equatorial Pacific. Topex-Poseidon and the Jason satellites have given the first frequent, global views of the full extent and life cycles of El Niño and La Niña events. Lee-Lueng dam you of JPL — project scientist for the first two ocean altimetry missions — pointed out, "Topex-Poseidon allowed us to follow their evolution and showed that these events weren't limited to just the tropics. It also gave us evidence of even longer-lasting ocean variations." One of these is the Pacific Decadal Oscillation, similar to El Niño and La Niña in character but with phases lasting up to several decades.

A numerical model of daily global tides using sea level data from Topex-Poseidon. Credit: ESR

Topex-Poseidon made the first global maps of tides, which changed scientists' understanding of how tides dissipate. The data show that a third of tidal energy dissipates in the open ocean, playing important and previously unknown roles in mixing water within the ocean.

On smaller space and time scales, satellite altimetry measurements provide information directly useful for marine storm prediction. Hurricanes are fueled by heat stored in the ocean below, and since the upper ocean expands and contracts as it heats and cools, sea level height is a marker for water temperature and heat content. So it is hardly surprising that ocean altimetry data are routinely used in forecasting hurricane strength.

In 2014, an unexpected forecasting use for altimetry data became operational. Bangladesh, whose 46-year history has encompassed death-dealing river floods, uses Jason-2 measurements of river levels in its flood forecasting and warning system. Within the first year using these data, Bangladesh's system enabled the most accurate, long-lead flood warnings ever given for that nation.

Those findings are astounding!

Keep bullshitting—that will keep AGW away, in what passes for your mind.

How much did AGW add to Hurricane Harvey.

The rainfall associated with it is smashing all Texan records! AGW causes more evaporation and, of course, subsequent precipitation.


https://www.theatlantic.com/science/archive/2017/08/did-climate-change-intensify...