ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-13-1167-2013 The melting level stability anomaly in the tropics Folkins I. 1 Department of Physics and Atmospheric Science, Dalhousie University Halifax, B3H 3J5, Nova Scotia, Canada 01 02 2013 13 3 1167 1176 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/13/1167/2013/acp-13-1167-2013.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/13/1167/2013/acp-13-1167-2013.pdf

On short timescales, the effect of deep convection on the tropical atmosphere is to heat the upper troposphere and cool the lower troposphere. This stratiform temperature response to deep convection gives rise to a local maximum in stability near the melting level. We use temperature measurements from five radiosonde stations in the Western Tropical Pacific, from the Stratospheric Processes and their Role in Climate (SPARC) archive, to examine the response of this mid-tropospheric stability maximum to changes in surface temperature. We find that the height of the stability maximum increases when the surface temperature increases, by an amount roughly equal to the upward displacement of the 0 °C melting level. Although this response was determined using monthly mean temperature anomalies from an 10 yr record (1999–2008), we use model results to show that a similar response should also be expected on longer timescales.

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