Jason and our Ocean Planet Mission Kit National Aeronautics and Space Administration Jet Propulsion Laboratory Pages 4 and 5 Content Moving towards operational oceanography Pages 6 and 7 In the footsteps of TOPEX/POSEIDON Pages 8 to 11 The satellite and its payload Pages 12 and 13 Launch and first operations Pages 14 to 16 Ground segment and data processing Pages 16 and 17 The millimeter per year challenge Pages 18 to 20 Jason and climate forecasting Pages 21 to 23 Jason serving seafarers… Pages 24 and 25 Backed by the world’s scientific community Pages 26 and 27 French players among the Argonauts Pages 28 and 29 French - US space cooperation with unparalleled accuracy, surface Moving towards operational temperatures, water colors, wind speed and direction, and sea surface oceanography topography. The Franco-American satellite The oceans are a fundamental element in our planet’s climatic system. TOPEX/POSEIDON was launched We should be able to monitor their conditions at all times, in the farthest in 1992, as a follow-up to reaches of our blue planet. We should be able to describe them, explain SEASAT (1978), GEOSAT (1985). them and forecast their changes. Together with ERS-1/2 (1991, 1995), it showed the wide range of oceanographic applications that can One may wonder if our planet was “predictability” of oceanic changes, be obtained from space. Using very Ocean dynamic topography as seen by the TOPEX/POSEIDON altimeter. The American satellite Seasat, launched incorrectly named—we call it Earth, because it is now accepted that the powerful radar altimetry technology, in 1978, marked the beginning of a new era for oceanography. but water covers 71% of its surface ocean has a fundamental disruptive the sharp eye of this satellite can Progressing from research to of sophistication, the global in-situ and seems to be absent from the and regulating role in the Earth’s detect the slightest variations in practical applications is always observation network will also be other planets in our solar system. climate. sea level with an accuracy of about delicate, and this change is currently enhanced and maintained. This is Water covers 360 million sq. km., 1 centimeter. Satellite altimetry has under way. Regional operational the goal of the ARGO program, more than forty times the size of the Our limited view of the ocean has revolution-ized physical oceanography services have already which will put more than United States, and oceans contain become much sharper over the last oceanography, giving access for been set up; examples are the 3,000 profiling floats across the thirty years. Just a few decades ago, 97% of the liquid water on Earth. the first time to quick, synoptic, SOPRANE system developed by world’s oceans by the year 2005. the thought that we could have a global and regular measurements of SHOM in the north Atlantic and The Jason name continuous, real-time global view of This water, which is in a constant ocean surface topography. The half- the European MFSPP project The success of these initiatives state of flux, plays a key role in million measurements gathered by (Mediterranean Forecasting System has shown that a large number Jason is a figure in Greek mythology. climatic and environmental changes the satellite over all the Earth’s Pilot Project). The next step is of scientific, technical and opera- Leading the famous Argonauts expedition, he went on a search for the on Earth. This is because its inertia oceans every 10 days have allowed to go global, with, in particular, tional skills can be successfully is much greater than that of the Golden Fleece, which was guarded by a scientists to regularly draw up the international program GODAE mobilized to implement opera- dragon in the Black Sea. atmosphere—its mass is 500 times charts of sea currents, follow their (Global Ocean Data Assimilation tional oceanography, which is now as great. seasonal and annual variations and Experiment), which will be both necessary and feasible. His ship, Argo, provided real-time observe the oceanic signatures of operational in 2003. The information about sea conditions and The Earth’s climate follows the major climatic anomalies, such MERCATOR center, the French Providing weather forecasts for communicated with its crew. After several years of searching, and crossing rhythm of its seasons and its Sun as the 1997-99 El Niño/La Niña part of the GODAE project, will shipping and commercial fishing that heats it unequally. The oceans, the Mediterranean from end to end, phenomenon. This has helped provide high-resolution 3D oceanic fleets, forecasting major abnormal Jason finally reached his goal. atmosphere, landmasses and ice scientists better understand and description and forecasts on a climatic events, and better distribute this heat through the describe the complex mechanisms planetary scale. Since January 2001, managing coastal areas… Every civilization needs myths and natural circulation of winds and sea and interactions among the oceans’ a preliminary operational version of Satellite altimetry data provided by successful quests, and the Argonauts' expedition included both of these. currents. Many oceanic parameters are currently different variability modes. MERCATOR is providing forecasts Jason-1, and a permanent in situ measured from space: temperature, This will also be the case for Jason, water color, wind, waves and dynamic for the northern and tropical areas and satellite observation network, which will showcase the two driving The series of catastrophes we topography. With the TOPEX/POSEIDON of the Atlantic Ocean. While satellite will help us better understand our components of space activity: have experienced in recent years— mission living up to expectations, systems and oceanic models are “ocean planet” and better forecast a quest (research) and a conquest (the the ocean seemed unrealistic; at that flooding, powerful storms, climatic satellite altimetry has become an being developed to increasing levels its changing moods. implementation of applications). time, only partial and intermittent changes related to “El Niño” and indispensable discipline in the “La Niña”—gave us a sudden wake- in situ data was available. This is no longer the case, thanks to the development of a new challenge, up call and made us notice just how that of operational oceanography. deep an effect climatic changes can many satellites that monitor the Earth and its oceans, flying over This challenge has been spurred have on our daily life. Scientists on by the success and interest have also needed to examine the the entire surface of the planet in just a few days, and measuring, generated by recent oceanic space causes, the consequences and the missions and their related research. The ocean is constantly changing: on the surface, these changes can take from a few hours This is the case, for example, to a few years; but in its deepest areas, these changes can occur over several centuries. with several pioneer programs such as WOCE (World Ocean Sea-to-air Circulation Experiment), heat transfer TOGA-COARE (observing climatic anomalies in the tropical Pacific region), and more recently the By the year 2005, more than 3,000 profiling floats, spread out across the Warm shallow CLIVAR (Climate Variability and current world’s oceans, will provide real-time information on the surface and Jason on his ship, the Argo, searching for Predictability) research program. deep layers of the ocean, complementing space measurements. the Golden Fleece. Cold and salty 5 4 deep current Eddy kinetic energy In the footsteps of T/P - ERS TOPEX/POSEIDON March 3, 1997 March 23, 1998 The main research objectives for the new Jason-1 altimetry mission were June 9, 1997 defined after examining feedback from the TOPEX/POSEIDON mission. April 10, 1997 May 10, 1997 Sea level anomaly May 10, 1998 The first discipline to benefit from these remarkably accurate tools is physical oceanography. But other disciplines in Earth sciences, also benefited greatly. The El Niño phenomenon was observed in its entirety, and continually, for the first time in 1997-98 thanks to TOPEX/POSEIDON. Launched into a 66° orbit, at an Multi-season to complex, and are subject to many even using a system as efficient Other applications in altitude of 1336 km, Jason-1 will multi-year variability POP model different types of influence: an and accurate as TOPEX/POSEIDON. geodesics, geophysics, follow the same ground tracks as accumulation of organic matter Confirming these observations its predecessor TOPEX/POSEIDON. and fresh water carried by rivers requires the accumulation of several glaciology and hydrology This oceanic variability, which Covering these tracks every 10 days, and streams; glacial action in years of this type of measurement. especially affects major oceanic it will detect the slightest variations high latitudes; coastal swamps; Altimetric sea level measurements in sea level and will provide high- currents, has a significant effect This is why it is necessary to add and interactions between coastal first represent the signal from the quality data to different research on climatic changes. The seasonal Jason-1 measurements to those currents and deep-sea currents. marine geoid, the result of the programs. cycle, for example, leads to an made by TOPEX/POSEIDON. Jason-1, together with the European Earth’s gravity on the ocean, whose increase or decrease in sea level Space Agency’s ENVISAT satellite, amplitude is 10 to 100 times higher in each hemisphere, exceeding will be excellent tools for observing Tides than that of the oceans’ dynamic 15 cm in some areas; there can be and resolving this type of topography. Geophysicists also have significant variations from one year variability. TOPEX/POSEIDON data has helped access to a great deal of data to study to the next. The recent occurrences develop several models that can bathymetry and plate tectonics with of the “El Niño” phenomenon, forecast the main diurnal and semi- levels of precision and resolution especially the pronounced case in Altimetry, used to better describe and Changes in the mean diurnal components of ocean tides that had never been reached before.