Ocean robots to hit target thanks to New Zealand

It has travelled over 65 000 nautical miles, endured big seas, and even survived a harbour-side raid by pirates, all to deploy ocean-profiling Argo floats.

2 October 2007

Kaharoa's Argo voyages, including those planned for 2008. Kaharoa deploys Argo floats in some of the most remote parts of the world's oceans.

Now another Argo deployment from the NIWA research vessel Kaharoa is almost certain to mark a feat of worldwide scientific importance.

The global ocean observing network, Argo, is nudging its target of 3000 operational floats taking the pulse of the world’s oceans. The 3000^th float is almost certain to be one of the 64 being deployed by NIWA’s RV Kaharoa on its Argo3000 voyage from Wellington to Valparaiso, Chile.

The voyage was formally launched by Hon Steve Maharey, Minister for Research, Science & Technology, today.

Argo floats are like weather balloons for the oceans, sending data back via satellite. “With 3000 floats, we have a truly global array spread over the ice-free parts of the world’s oceans,” says Professor Dean Roemmich, co-chair of the International Argo Steering Group.

Professor Roemmich is keen to point out that, as the floats have a limited life, about 800 new floats will be needed each year to maintain the array.

RV Kaharoa holds the world record for the most Argo deployments. The 28-metre vessel has deployed over a quarter of the floats currently operating in the southern hemisphere. “Without Kaharoa, the Argo network could not have achieved global coverage,” says Professor Roemmich.

Argo data have already been used in almost 300 scientific publications, making new discoveries about the oceans and monitoring global warming. Argo is used by 13 operational weather and climate services, e.g., to improve seasonal forecasts.

“Before Argo, we made ocean measurements on research trips and dropped temperature probes from container ships. Data were patchy, mostly from summer, and almost never covered New Zealand’s backyard – the remote but climatically important Southern Ocean,” says NIWA oceanographer Dr Phil Sutton.

Kaharoa’s Argo voyages are a collaborative effort between NIWA, Scripps Institution of Oceanography (UCSD), and University of Washington (Seattle), funded by the US National Oceanic and Atmospheric Administration through the National Ocean Partnership Program.