By Sid Perkins
Data gathered by cargo ships plying the North Atlantic between 2002 and 2007 show that the ability of surface waters there to sop up CO2 varies considerably but somewhat predictably from year to year. The finding may help scientists better estimate the future rate at which the planet-warming gas will build up in the atmosphere.
Ups and downs in the ocean’s CO2 uptake are important to atmospheric levels because globally, the portion of the gas that isn’t absorbed by oceans or taken up by land plants accumulates in the atmosphere.
The newly released, six-year set of oceanographic data is the largest of its kind, says Arne Körtzinger, a chemical oceanographer at the Leibniz Institute for Marine Sciences in Kiel, Germany. While scientific research vessels are limited to occasional cruises, cargo ships constantly cross the oceans, he notes.