Abstract
Abstract. The ground-based microwave radiometer MIAWARA-C recorded the upper stratospheric and lower mesospheric water vapour distribution continuously from June 2011 to March 2013 above the Arctic station of Sodankylä, Finland (67.4° N, 26.6° E) without major interruptions and offers water vapour profiles with temporal resolution of 1 h for average conditions. The water vapour time series of MIAWARA-C shows strong periodic variations in both summer and winter related to the quasi-2-day wave. Above 0.1 hPa the amplitudes are strongest in summer. The stratospheric wintertime 2-day wave is pronounced for both winters on altitudes below 0.1 hPa and reaches a maximum amplitude of 0.8 ppmv in November 2011. Over the measurement period, the instrument monitored the changes in water vapour linked to two sudden stratospheric warmings in early 2012 and 2013. Based on the water vapour measurements, the descent rate in the vortex after the warmings is 364 m d−1 for 2012 and 315 m d−1 for 2013.
Highlights
This paper focuses on the effect of stratospheric warmings (SSWs) and the quasi-2-day wave (Q2DW)
Observational data of middle atmospheric water vapour obtained at the Arctic research station in Sodankylä have been presented
The focus has been put on discussing the water vapour time series measured by the ground-based microwave radiometer MIAWARA-C
Summary
Ground-based microwave radiometry is the only method capable of obtaining middle atmospheric water vapour time series with temporal resolution of the order of an hour and well suited for the investigation of dynamical effects in polar regions. The winter polar region dry mesospheric air descends inducing horizontal gradients in the water vapour VMR, which are sustained by the vortex edge. The summer polar region, upwelling of relatively humid stratospheric air results in high water vapour VMR in the mesosphere. In addition to analysis of dynamical variables, Limpasuvan and Wu (2003) analysed the summertime Q2DW in mesospheric water vapour measured by UARS MLS and found amplitudes of up to 0.35 ppmv near the mesopause. The two SSWs of 2012 and 2013 are discussed complementing the measured water vapour profiles with temperature data from Aura MLS and ECMWF model data
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
