How much water flows in the Antarctic Circumpolar Current? Scientists are trying to find the answer.
Voyage leader, Dr Mike Williams of the National Institute of Water and Atmospheric Research (NIWA), is working with scientists from Australia and New Zealand to find the answer to this important question.
The Antarctic Circumpolar Current is the largest current in the world. ‘It’s been estimated that this current is 110–150 times larger than all the water flowing in all the rivers of the world,’ says Dr Mike Williams. He also adds that,
In terms of the world’s oceans, New Zealand is not some tiny backwater, or the proverbial last bus stop on the planet — we are right beside the motorway.
Dr Mike Williams
The Antarctic Circumpolar Current travels clockwise around Antarctica. It is a vital link in the global ocean conveyor, connecting the waters of the Atlantic, Indian and Pacific Oceans. And scientists want to know exactly how much water flows past New Zealand. This vital information will be important for understanding how the current affects our climate.
They planned to measure the current by deploying nine strings of current meters in two gaps in the Macquarie Ridge, which runs southwest of New Zealand past Macquarie Island.
The strings of current meters will stay in place for at least a year before being retrieved for analysis. ‘Currents vary through the seasons so we need to collect at least a year’s worth of data,’ says Dr Williams.
The team will also systematically measure the temperature and salinity of this part of the ocean for the first time since the 1960s, looking for any climate-related changes, and collect water samples to measure nutrients available for marine life.
Hopefully, once the data has been analysed in 2008, we will know exactly how much water flows in the Antarctic Circumpolar Current!
Find out more about the Antarctic Circumpolar Current in this article looking at the Currents in the Southern Ocean and Ocean motion.
