Anxious weeks for ocean monitoring network

Last month, American scientists began retrieving monitoring instruments that have been gathering data on the oceans since 2009 as part of the Ocean Observatories Initiative. The US National Science Foundation (NSF) decided to terminate the project shortly after President Trump sacked all 22 members of the scientific advisory board. However, the decision was reversed by Congress on 17 June. ‘Terminating this project would have been a real disaster for climate research,’ says University of Groningen professor Richard Bintanja. ‘Moreover, the Americans would have had less insight into the formation of hurricanes that ravage the east coast of the US in the autumn.’ This may have been the deciding factor in reversing the decision.

A network of fixed monitoring stations continuously measures, among other things, the temperature, salinity, and carbon dioxide concentration in the water at a number of locations. In addition, there is a fleet of around four thousand platforms that collect data whilst drifting with ocean currents and regularly diving to depths of a few thousand metres.

‘Many countries, including the Netherlands, have funded a number of these platforms, and we share all the data,’ explains Bintanja. ‘The information gathered by all these instruments is of great importance to our climate models, precisely because they take continuous measurements across all the oceans. This requires a high density of measurement platforms, because the ocean isn’t just one big mass of water; there’s a surprising amount of variation within it.’ A long time series of measurements is needed to accurately identify the changes in the climate, because global warming proceeds in fits and starts. Interrupting that series would therefore be detrimental.

The instruments also measure how heat is transported from the equator to the poles. The warm Gulf Stream, which gives north-western Europe a temperate climate, is one example of this. ‘That Gulf Stream depends heavily on water that sinks off Greenland and then flows back towards the equator. Small changes in the ocean around Greenland are crucial in this regard.’ And so it is important to keep a close eye on this.

In May and early June, the first OOI instruments were retrieved from the ocean. This would not only have major consequences for climate research. Bintanja: ‘Without this data, our weather forecasts are much less accurate.’ The NSF has announced that the retrieved instruments will be reinstalled. Climate scientists can breathe a sigh of relief, at least for now. Bintanja: ‘Relations with our American colleagues are excellent, but also in climate research, we must become less dependent on the US.’