Whether the tropical upper atmosphere has been warming, and at what rate, has been a controversial issue over the past decades, given the differences between direct observations and climate model simulations. New observational data published online this week in Nature Geoscience show a warming rate of about 0.65?C per decade since 1970, which is broadly in line with model simulations, and therefore increases confidence in the climate models.
Previous studies using satellite and direct temperature measurements of the troposphere ? the lowest region of the earth’s atmosphere ? failed to show the warming trend predicted by climate models; most likely because of biases within the methods. To get around these potential biases, Robert Allen and Steven Sherwood used wind measurements, which are more robust than temperature observations, and a meteorological equation linking winds to temperatures, to derive temperature trends. Their results show a warming maximum in the upper atmosphere over the tropics, as expected from climate models.
In an accompanying News and Views article, Peter Thorne states that the authors ‘provide [