New ocean research provides clear evidence of a human "fingerprint" on climate change, showing that specific signals from human activities have altered the amplitude of the seasonal cycle of sea surface temperatures (SSTs). "This is groundbreaking evidence that there is a signal of human-caused climate change in increasing ocean temperatures," says co-author Benjamin Santer, associate scientist and distinguished scientist in the Department of Physical Oceanography at the Woods Hole Oceanographic Institution. ₍ WHOI).

"We show that the human-induced signal in the seasonal cycle of sea surface temperature (SST) emerged from the noise of natural variability. Geographical patterns of changes in the amplitude of the SST seasonal cycle (SSTAC) reveal two distinctive features: an increase in the northern midlatitudes of the hemisphere is related to changes in mixed layer depth and a robust dipole pattern between 40˚S and 55˚S, which is mainly driven by surface wind changes, " states the magazine published in Nature Climate Change. (Woods Hole Oceanographic Institution, more at phys.org)