These being the hottest waters and the Southern Ocean being the coldest made the rest of the world ocean simple, assuming linear interpolation, of course. On the Eltanin we remained at sea for 60 days, spending half that time getting to and from the research area. We collected water in Nansen bottles at 23 levels at perhaps only 30 stations, struggling to collect those few samples. Today, we sample continuously from sea surface to seafloor at well more than 100 stations in a 30-day cruise. We deploy instrumented drifters and moorings.
Satellites provide images of the sea surface temperatures over the entire ocean.
They monitor sea level changes and wind stress on the ocean surface and look at sea ice cover hiding under the clouds. When I look now at ocean intricacies exposed by these new observational methods, I wonder if we had known of the ocean s complexity, might we in the 1960s have been too disheartened to move ahead. Sophisticated computer modeling has become a major tool for investigating the complex dynamics of the ocean and the climate, but the foundation and the validity of any model still rely on actual observations. It s the combination of models and observations that counts. I ve never lost the feeling that unexpected discoveries are still lurking out there.