ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-11-5485-2011 Tropopause height at 78° N 16° E: average seasonal variation 2007–2010 Hall C. M. 1 Hansen G. 2 Sigernes F. 3 Kuyeng Ruiz K. M. 4 Tromsø Geophysical Observatory, University of Tromsø, Norway Norwegian Institute for Air Research, Tromsø, Norway The University Centre in Svalbard, Longyearbyen, Norway Jicamarca Radio Observatory, Lima, Peru 15 06 2011 11 11 5485 5490 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/11/5485/2011/acp-11-5485-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/5485/2011/acp-11-5485-2011.pdf

We present a seasonal climatology of tropopause altitude for 78° N 16° E derived from observations 2007–2010 by the SOUSY VHF radar on Svalbard. The spring minimum occurs one month later than that of surface air temperature and instead coincides with the maximum in ozone column density. This confirms similar studies based on radiosonde measurements in the arctic and demonstrates downward control by the stratosphere. If one is to exploit the potential of tropopause height as a metric for climate change at high latitude and elsewhere, it is imperative to observe and understand the processes which establish the tropopause – an understanding to which this study contributes.

 References % vor jede Referenz Bègue, N., Bencherif, H., Sivakumar, V., Kirgis, G., Mze, N., and Leclair de Bellevue, J.: Temperature variability and trends in the UT-LS over a subtropical site: Reunion (20.8° S, 55.5° E), Atmos. Chem. Phys., 10, 8563–8574, http://dx.doi.org/10.5194/acp-10-8563-2010doi:10.5194/acp-10-8563-2010, 2010. Gage, K. S. and Green, J. L.: Tropopause detection by partial specular reflection with very-high-frequency radar, Science, 203, 1238–1240, http://dx.doi.org/10.1126/science.203.4386.1238doi:10.1126/science.203.4386.1238, 1979. Hall, C. M., Brekke, A., and Cannon, P. S.: Climatic trends in E-region critical frequency and virtual height above Tromsø (70° N, 10° E), Ann. Geophys., 25, 2351–2357, http://dx.doi.org/10.5194/angeo-25-2351-2007doi:10.5194/angeo-25-2351-2007, 2007. Hall, C. M., Röttger, J., Kuyeng, K., Sigernes, F., Claes, S., and Chau, J. L.: Tropopause altitude detection at 78° N, 16° E, 2008: first results of the refurbished SOUSY radar, Radio Science, 44, RS5008, http://dx.doi.org/10.1029/2009RS004144doi:10.1029/2009RS004144, 2009. Hansen, G. and Svenøe, T.: Multilinear regression analysis of the 65-year Tromsø total ozone series, J. Geophys. Res., 110, D10103, http://dx.doi.org/10.1029/2004JD005387doi:10.1029/2004JD005387, 2005. Highwood, E. J., Hoskins, B. J., and Berrisford, P.: Properties of the arctic tropopause, Q. J. Roy. Meteorol. Soc., 126, 1515–1532, 2000. Hu, Y., Xia, Y., and Fu, Q.: Tropospheric temperature response to stratospheric ozone recovery in the 21st century, Atmos. Chem. Phys. Discuss., 10, 22019–22046, http://dx.doi.org/10.5194/acpd-10-22019-2010doi:10.5194/acpd-10-22019-2010, 2010. Lee, J. S.: Speckle suppression and analysis for synthetic aperture radar images, Opt. Eng., 25, 636–643, 1986. Manney, G. L. and Sabutis, J. L.: Development of the polar vortex in the 1999–2000 Arctic winter stratosphere, Geophys. Res. Lett., 27, 2589–2592, 2000. Rishbeth, H. and Clilverd, M.: Long-term change in the upper atmosphere, Astronomy and Geophysics, 40, 3.26–3.28, 1999. Rishbeth, H. and Roble, R. G.: Cooling of the upper atmosphere by enhanced greenhouse gases – modelling of thermospheric and ionospheric effects, Planet. Space Sci., 40, 1011–1026, 1992. Roble, R. G. and Dickinson, R. E.: How will changes in carbon-dioxide and methane modify the mean structure of the mesosphere and thermosphere?, Geophys. Res. Lett., 16, 1441–1444, 1989. Röttger, J. and Hall, C. M.: Climatology of the radar tropopause over Svalbard 2005 and 2006, Proceedings MST-11 workshop India 2006, ISBN 10:0230-63414-1, 726–729, 2007. Salby, M. L.: Fundamentals of Atmospheric Physics, Academic Press, San Diego, California, 627~pp., ISBN 0-12-615160-1, 1996. Santer, B. D., Sausen, R., Wigley, T. M. L., Boyle, J. S., AchutaRao, K., Doutriaux, C., Hansen, J. E., Meehl, G. A., Roeckner, E., Ruedy, R., Schmidt, G., and Taylor, K. E.: Behavior of tropopause height and atmospheric temperature in models, reanalyses, and observations: Decadal changes, J. Geophys. Res., 108(D1), 4002, http://dx.doi.org/10.1029/2002JD002258doi:10.1029/2002JD002258, 2003. Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K. B., Tignor, M., and Miller, H. L. (Eds.): Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, 996~pp., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 2007. Ulich, T. and Turunen, E.: Evidence for long-term cooling of the upper atmosphere in ionosonde data, Geophys. Res. Lett., 24, 1103–1106, 1997. Vogler, C., Brönnimann, S., and Hansen, G.: Re-evaluation of the 1950–1962 total ozone record from Longyearbyen, Svalbard, Atmos. Chem. Phys., 6, 4763–4773, http://dx.doi.org/10.5194/acp-6-4763-2006doi:10.5194/acp-6-4763-2006, 2006. WMO: Measurements of upper air temperature, pressure, and humidity, Guide to Meteorological Instruments and Methods of Observation, 6th ed., WMO I.12-1–I.12-32, 1996. Zängl, G. and Hoinka, K. P.: The tropopause in polar regions, J. Climate, 14, 3117–3139, 2001.