Current Projects
A number of efforts have been initiated in recent years to apply data assimilation to estimate the physical state of the ocean, including temperature, salinity, currents, and sea level, in recent years. There are three alternative state estimation approaches. The first approach is used by the ‘no-model’ analyses, for which temperature or salinity observations update a first guess provided by climatological monthly estimates.
The second approach is that of the sequential data assimilation analyses, which move forward in time from a previous analysis using a numerical simulation of the evolving temperature and other variables produced by an ocean general circulation model. The simulation provides the first guess of the state of the ocean at the next analysis time, while corrections are made to this first guess based on observations of variables such as temperature, salinity, or sea level.
The third approach is 4D-Var, which in the implementation described uses the initial conditions and surface forcing as control variables to be modified in order to be consistent with the observations as well as a numerical representation of the equations of motion through iterative solution of a giant optimization problem.
Read more about this topic: Ocean Reanalysis
Famous quotes containing the words current and/or projects:
“I have come to believe ... that the stage may do more than teach, that much of our current moral instruction will not endure the test of being cast into a lifelike mold, and when presented in dramatic form will reveal itself as platitudinous and effete. That which may have sounded like righteous teaching when it was remote and wordy will be challenged afresh when it is obliged to simulate life itself.”
—Jane Addams (1860–1935)
“One of the things that is most striking about the young generation is that they never talk about their own futures, there are no futures for this generation, not any of them and so naturally they never think of them. It is very striking, they do not live in the present they just live, as well as they can, and they do not plan. It is extraordinary that whole populations have no projects for a future, none at all.”
—Gertrude Stein (1874–1946)