Regions of the atmosphere. Credit: NOAA

Media Contact: Jana Goldman, jana.goldman@noaa.gov
November 15, 2010 The troposphere, the lower part of the atmosphere closest to the Earth, is warming and this warming is broadly consistent with both theoretical expectations and climate models, according to a new scientific study that reviews the history of understanding of temperature changes and their causes in this key atmospheric layer. Scientists at NOAA, the NOAA-funded Cooperative Institute for Climate and Satellites (CICS), the United Kingdom Met Office, and the University of Reading in the United Kingdom contributed to the paper, “Tropospheric Temperature Trends: History of an Ongoing Controversy,” a review of four decades of data and scientific papers to be published today by Wiley Interdisciplinary Reviews – Climate Change, a peer-reviewed journal. The paper documents how, since the development of the very first climate models in the early 1960s, the troposphere has been projected to warm along with the Earth’s surface because of the increasing amounts of greenhouse gases in the atmosphere. This expectation has not significantly changed even with major advances in climate models and is in accord with our basic physical understanding of atmospheric processes.            In the 1990s, observations did not show the troposphere, particularly in the tropics, to be warming, even though surface temperatures were rapidly warming. This lack of tropospheric warming was used by some to question both the reality of the surface warming trend and the reliability of climate models as tools. This new paper extensively reviews the relevant scientific analyses — 195 cited papers, model results and atmospheric data sets — and finds that there is no longer evidence for a fundamental discrepancy and that the troposphere is warming. “Looking at observed changes in tropospheric temperature and climate model expectations over time, the current evidence indicates that no fundamental discrepancy exists, after accounting for uncertainties in both the models and observations,” said Peter Thorne, a senior scientist with CICS in Asheville, N.C., and a senior researcher at North Carolina State University. CICS is a consortium jointly led by the University of Maryland and North Carolina State University. … 

Review of Four Decades of Scientific Literature Concludes Lower Atmosphere is Warming