Climate change spurs global speedup of ocean currents. Rising winds boost flows in tropics and southern ocean
Voosen, Paul
For nearly 25 years, the ocean's great continent-wrapping currents, each one moving as much water as all the world's rivers combined, have been rapidly speeding up, partly because of global warming, a new study concludes. Based on observations combined with models, the authors claim that from 1990 to 2013, the energy of the currents increased by some 15% per decade. No sustained, direct measurements of currents around the world are available, so the team turned to reanalyses, which combine observations of the ocean and atmosphere with computer models to fill in the gaps and produce a global picture. Five different models showed a distinct rise starting around 1990. Independent data from the Argo array, a fleet of nearly 4000 robotic floats deployed around the world, showed a similar rise from 2005 to 2010. The increase is driven by higher winds over the oceans, the authors say. If the acceleration is verified and continues, it could affect jet streams, weather patterns, and the amount of heat stored in the ocean's depths. </p>
Accès à la notice sur le site du portail documentaire de Météo-France