The strength of Pacific trade winds may have influenced the rate of climate warming in the early twentieth century, reports a study published online in Nature Geoscience. The rapid global warming between 1910 and 1940 coincided with weak Pacific trade winds, whereas the subsequent slowdown in warming rate, from 1940 to about 1970, was accompanied by stronger winds.
Diane Thompson and co-authors analysed corals from the western Pacific Ocean to reconstruct westerly wind bursts in the Pacific between 1894 and 1982. They found that westerly wind bursts, which are associated with weak Pacific trade winds, were most frequent during the period of rapid warming from 1910 to 1940, and less frequent during the following 30 years or so, when warming was stable. The authors conclude that Pacific wind strengths and global warming rates are closely connected.
In an accompanying News and Views article, Stefan Bronnimann suggests that the work “links early twentieth century climate to the unexpectedly slow warming rates in the beginning of the twenty-first century.”