But it is not only the thermal energy stored deep within the oceans that causes the variation in sea level, gravity also has an influence.
The subterranean geology is not uniform, some regions are more dense than others. This causes a subtle but significant shift in the Earth's gravitational force.
To measure the influence of gravity and its impact on ocean topography and currents, the European Space Agency (Esa) plans to launch an arrow-like satellite called the Gravity field and steady-state Ocean Circulation Explorer (Goce).
'Arrow' to map Earth's tug
"If we want to improve our climate models then we need to improve our knowledge of how the oceans move, and Goce will help us do that," mission scientist Dr Mark Drinkwater, from Esa, told BBC News.
By combining the data gathered by Goce and Jason-2, meteorologists and climate scientists will advance their understanding of the physical factors influencing the oceans and atmosphere.
Jason-2 is the latest addition to a series of satellites fitted with altimeters to map the sea surface.
The first, Topex/Poseidon, was launched in 1992 as an experiment to assess the effectiveness of high-accuracy altimeters to measure ocean dynamics from space.
Its success paved the way for the Jason-1/Poseidon-2 mission, launched in 2001.
Lessons learned from the previous missions have allowed the team building the Poseidon altimeter instrument for Jason-2 to improve its accuracy and reduce the margin of uncertainty to within 2.5cm.
Doesn't say how much more accurate than 1" they have managed yet, but at 2.5cm error allowance, your graph that I could not find on the site even after translating to English, the 3cm trending rise could be from 5.5 to .5cm. I'd like a link to the accompanying text of your jpg clip.