Physics of auroral phenomena : proceedings of the 40th annual seminar, Apatity, 13-17 March, 2017 / [ed. board: N. V. Semenova, A. G. Yahnin]. - Апатиты : Издательство Кольского научного центра РАН, 2017. - 143 с. : ил., табл.

*Physics o f Auroral Phenomena", Proc. XL Annual Seminar, Apatity, pp. 131-134, 2017 © Polar Geophysical Institute, 2017 Polar Geophysical Institute MONITORING OF VARIATIONS OF MIDDLE ATMOSPHERE OZONE IN POLAR LATITUDES OF ARCTIC DURING STRATOSPHERIC WARMING IN THE WINTER 2016 Y.Y. Kulikov1, V.G. Ryskin1, S.I. Osipov2, A.V. Poberovsky2, V.A. Yushkov 3 1Institute o fApplied Physics RAS, Nizhny Novgorod 2St. Petersburg State University, Saint Petersburg ъCentral Aerological Observatory, Dolgoprudny Introduction The study of response o f the middle atmosphere (stratosphere and mesosphere) to any external impact (variations of sunlight, flux of cosmic ray particles, eruptions of volcanoes, and anthropogenesis factors) is an important physical problem. Ozone and temperature are basic atmospheric parameters. Ozone and temperature are important atmospheric parameters. The correlation o f these parameters is of significant interest from the viewpoint o f thermal balance of the middle atmosphere. The basic heating of the stratosphere (altitude range of 30-50 km) is caused by absorption of solar ultraviolet radiation by ozone molecules. Thermal changes influence the rate o f ozone formation and destruction. Other types of wave processes can redistribute the structures of vertical profiles of ozone and temperature in the middle atmosphere. Sudden stratospheric warming (SSW) affects a lot of widely known atmospheric wave processes. Ground-based microwave radiometry allows investigation o f ozone variations during large-scale wave disturbances in the middle atmosphere, such as, for example, stratospheric warming [1]. Last years there was an additional interest to SSW. In the winter o f 2012-2013 there was a unique warming caused temperature increase a few tens of degrees at pressure level 10 hPa. In microwave and optical observations in Tomsk, there were noted visible variations of ozone and temperature in the middle atmosphere [2, 5]. The ozone concentration at altitudes from 25 to 60 km increased by 1 .5 -2 times. The maximum of positive deviation of temperature from its month average value reached 70 К at altitude of 30 km. Diumal variations of ozone at altitude of 60 km associated with sunset and sunrise was about 30%. In addition, this warming according to [3] caused variations of the total electron content up to 100% in equatorial ionosphere. In middle and polar latitude variations of the electron concentration hypothetically are associated with variations of the neutral composition. In [4] it is discussed the possible role of the middle atmosphere ozone on the relationship between mesosphere and ionosphere. In this paper we present some results of measurements o f the ozone emission line in January-March 2016 by method of microwave radiometry. Measurements of spectra of middle atmosphere ozone were executed with the help of mobile radiometer (work frequency 110836.04 MHz). The device was installed in 2007 at physical faculty in Peterhof (60N, 30E) in 28 km from the centre of Saint Petersburg [1]. Fig. 1 shows the general view of the microwave equipment (mobile ozonemeter). On the measured spectra were appreciated o f ozone vertical profiles in the layer of 22-60 km which were compared to satellite data MLS/Aura and SABER [ 6 ], and also with the data of ozonesonde at station Salekhard (67N, 67E), Sodankyla (67N, 27E) and Summit (73N, 38W). Significant variations in ozone number density, which were caused by sudden stratospheric warming in winter 2016, were observed in the atmosphere over Peterhof at altitudes of 40 to 60 km. Microwave ground-based equipment used in the experiment Method ground-based microwave radiometry is based on measurements of thermal atmospheric radiation in vicinity the ozone line in the range of millimeter and submiilimcter waves. Microwave observations are weakly dependent on weather conditions and the presence of atmospheric aerosols, and this is an advantage compared with observations in the optical and infrared wavelength ranges. In addition, the microwave ozone observations can run around the clock. In recent years it is managed to make a significant step forward towards the creation of a new generation of mobile microwave spectrometers [7]. The device consists of an uncooled heterodyne receiver tuned to a fixed frequency 110836.04 MHz corresponding to a rotational transition of ozone molecules 6 o, 6 - 61 , 5 , and multichannel spectrum analyzer. In front of receiver is a module that includes an antenna (scalar horn) and a switch to calibrate accepted intensity of atmospheric ozone line radiation. The beam width (by level -3 dB) of the horn antenna is 5.4°. The SSB noise temperature of the receiver is 2500 K. The SSB receive mode is provided by evanescent filter with direct losses of 0.5 dB and the suppression of the image channel of more than 20 dB. The spectrum analyzer consists of 31 filters with a variable bandwidth from 1MHz to 10 MHz and a full analysis bandwidth of 240 MHz. The parameters of the device allow to measure a spectrum of the emission ozone line for time about 15 min with a precision of ~ 2 %. Measurement of the spectra of thermal radiation is performed by a method of calibration for two "black body" loads that are at the boiling point of liquid nitrogen and at ambient temperature. Information about the content o f the O 3 is contained in the measured radio emission spectrum of the middle atmosphere. Using the inversion of the obtained 131