Australasian Science: Australia's authority on science since 1938

Pirates Preventing Climate Research

By Stephen Luntz

The rise of pirates off the coast of Somalia is proving a problem for scientific research as it is no longer safe to deploy Argo floats in the north-western Indian Ocean.

The rise of pirates off the coast of Somalia is proving a problem for scientific research as it is no longer safe to deploy Argo floats in the north-western Indian Ocean. A shortage of data could reduce the accuracy of weather predictions for the coming summer, and impact longer-term climate change projections.

Australian scientists have called on the military for support. “We have not been able to seed about one-quarter of the Indian Ocean since the increase in piracy,” says Dr Ann Thresher of the CSIRO Wealth from Oceans Flagship.

More than 3000 Argo floats have been deployed across the Earth’s oceans. The floats spend time sinking to depths of 2000 metres, where they take temperature and salinity readings before returning to the surface to communicate the findings back to base.

The floats typically have lifespans of 4 years. While Thresher says that better batteries can extend this to 9 years, most are damaged or stranded long before, making regular redeployment a necessity.

Surface data ares available from satellites, but Thresher says that some conditions still require monitoring from ships, and this is failing as many avoid the area.

Deep-sea temperature measurements are important for climate change research. Thresher says conditions at 500 metres depth can affect the climate in nations that border the Indian Ocean over time spans of a few months.

One pole of the Indian Ocean Dipole, which strongly influences rainfall in southern Australia, lies in the unsafe zone. Thresher says this won’t prevent predictions from being made, but increases the margin for error.

Some floats have been deployed by US Navy ships patrolling the area to protect shipping lanes. The Australian Navy has also been asked to help, but Thresher says that the first request was made too late for a recent deployment. “They’ll probably take floats the next time they go, but they can’t tell us too much about their movements beforehand.”