Vertical Distribution of Water Vapor in the Arctic Stratosphere in JanuaryFebruary 2004 from Data of the LAUTLOS Field Campaign

V. A. Yushkov*, A. N. Luk’yanov*, S. M. Khaikin*, L. I. Korshunov*, R. Neuber**, M. Muller**, E. Kuro***, R. Kivi***, H. Voemel****, Y. Sasano*****, and H. Nakane*****

* Central Aerological Observatory, Dolgoprudnyi, Moscow region, Russia Е-mail: vladimir@caomsk.mipt.ru

** Alfred Wegener Institute for Polar and Marine Research, Potsdam, Germany

Е-mail: rneuber@awi-potsdam.de

*** Arctic Research Centre, Finnish Meteorological Institute, Sodankylä, Finland

E-mail: esko.kyro@fmi.fi

**** University of Colorado, Boulder, CO, USA

E-mail: holger.voemel@colorado.edu

***** National Institute for Environmental Studies, Tsukuba, Japan

E-mail: sasano@nies.go.jp

Izvestya RAN, physics of Atmosphere and Ocean, vol. 41, No. 5, 2005 p.563-570

Abstract

The results of measurements of water-vapor vertical profiles in the upper troposphere and lower stratosphere on board a meteorological sounding balloon with the use of a FLASH-B optical fluorescent hygrometer are presented. These results were obtained during the LAUTLOS–WAVVAP international experiment on the comparison of balloon hygrometers, which was carried out in January–February 2004 in northern Finland. Humidity values are determined inside, outside, and at the boundary of the circumpolar stratospheric cyclone. It is shown that, at a height of 20 km, the difference between the mixing ratios of water vapor outside and inside the cyclone can attain 1 ppm and increases with height. It is inferred that the layered structure of the vertical humidity profile at the stratospheric-cyclone boundary is caused by inhomogeneous advection of air masses. The humidity-profile layering is in good agreement with the layering of the potential-vorticity profile, which points to the dynamic nature of these layers. It is shown that decreased values of the water-vapor content observed in the polar stratosphere are not always controlled by dehydration processes associated with the formation and sedimentation of particles of polar stratospheric clouds.