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Repnev A.I.,Central Aerological Observatory Rosgidromet | Krivolutsky A.A.,Central Aerological Observatory Rosgidromet
Izvestiya - Atmospheric and Ocean Physics | Year: 2010

New information about the chemical composition of the stratosphere and mesosphere is reviewed. This information was obtained in different seasons in both hemispheres with the use of the MIPAS (IR limb sounder), Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY; UV-visible and near-IR nadir and limb viewer), and Global Ozone Mapping Spectrometer (GOMOS) instruments installed on the European Envisat satellite launched in 2002. Measurements with the MIPAS instrument make it possible to retrieve information about the composition of the nighttime atmosphere. It should be noted that several powerful solar proton events (SPEs) occurred on the Sun in the period of satellite measurements. As is well known, the ionization of the polar atmosphere by SPEs is responsible for the intense interaction between ionic and neutral constituents below 100 km, which leads to the additional formation of nitrogen oxides and OH radicals destroying the ozone. Therefore, observations of the composition of the middle atmosphere in these periods are of great interest, because such situations serve as a unique test which makes it possible to check our knowledge not only about photochemical processes in the atmosphere but also about its interaction with cosmic plasma. The results of a comparison of model calculations with newly obtained data on the chemical composition, including those for SPE periods, are presented. © Pleiades Publishing, Ltd., 2010. Source

Krivolutsky A.A.,Central Aerological Observatory Rosgidromet | Cherepanova L.A.,Central Aerological Observatory Rosgidromet | Dement'Eva A.V.,Central Aerological Observatory Rosgidromet
Journal of Geophysical Research A: Space Physics | Year: 2015

Global circulation model of the Troposphere-Middle Atmosphere-Lower Thermosphere ARM (Atmospheric Research Model) is used to simulate the thermal and wind response to solar cycle-induced UV variations. ARM covers altitudes from 1 to 135 km and has corresponding spatial resolution: 1 km in altitude; 11.25 in longitude; 5 in latitude. Internal Gravity Waves parameterization and planetary waves (PWs) structure on the basis of observations are determined at the lower boundary of the model. Changes in UV radiation, which is absorbed by ozone and molecular oxygen, are introduced into the model to find the corresponding global wind and temperature response. Stationary PWs with zonal wave numbers 1-3 are included at lower boundary in model runs. The simulations show that atmospheric response to solar cycle has a visible nonzonal character with the amplitude of about 5 K in the troposphere for the winter season. The effect is rather smaller for summer due to the trapping PWs at lower altitudes. So, in accordance with the results of simulations, the link between the solar UV variability and the middle and low atmosphere strongly depends on the ozone and PWs activity. ©2015. American Geophysical Union. All Rights Reserved. Source

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