A year ago, we reported on the launch of a new XPRIZE competition—not to launch a rocket, but to build a better device to measure ocean pH. The aim was to produce something that could be added to automated platforms like ARGO floats to greatly expand pH data collection, which presently has to rely mostly on expensive research vessel cruises.

Teams are competing for a pair of $1 million prizes put up by Wendy Schmidt—who, together with her husband Eric Schmidt, just donated $500,000 to help keep the famous atmospheric CO 2 monitoring program at the Scripps Institution of Oceanography running.

The first of three stages in the competition will begin next week. The 18 teams who were selected for the competition will place their devices into carefully controlled tanks of water at the Monterey Bay Aquarium Research Institute. Over three months, the devices will be judged on the accuracy, precision, and stability of their pH measurements.

In February, some teams will move onto the next stage, deploying their devices in the challenging environment of Seattle’s Puget Sound for a month. In May, a final field test out in the Pacific will determine the winners.

You can read more about the teams in the competition on the XPRIZE website.