TY - JOUR

T1 - Propagation of stationary planetary waves in the upper atmosphere under different solar activity

AU - Koval, A.V.

AU - Gavrilov , N.M.

AU - Pogoreltsev , A.I.

AU - Shevchuk , N.O.

N1 - Koval, A.V., Gavrilov, N.M., Pogoreltsev, A.I. et al. Propagation of Stationary Planetary Waves in the Upper Atmosphere under Different Solar Activity. Geomagn. Aeron. 58, 281–289 (2018). https://doi.org/10.1134/S001679321802010X

PY - 2018/3

Y1 - 2018/3

N2 - Numerical modeling of changes in the zonal circulation and amplitudes of stationary planetary waves are performed with an accounting for the impact of solar activity variations on the thermosphere. A thermospheric version of the Middle/Upper Atmosphere Model (MUAM) is used to calculate the circulation in the middle and upper atmosphere at altitudes up to 300 km from the Earth’s surface. Different values of the solar radio emission flux in the thermosphere are specified at a wavelength of 10.7 cm to take into account the solar activity variations. The ionospheric conductivities and their variations in latitude, longitude, and time are taken into account. The calculations are done for the January–February period and the conditions of low, medium, and high solar activity. It was shown that, during high-activity periods, the zonal wind velocities increases at altitudes exceeding 150 km and decreases in the lower layers. The amplitudes of planetary waves at high solar activity with respect to the altitude above 120 km or below 100 km, respectively, are smaller or larger than those at low activity. These differences correspond to the calculated changes in the refractive index of the atmosphere for stationary planetary waves and the Eliassen–Palm flux. Changes in the conditions for the propagation and reflection of stationary planetary waves in the thermosphere may influence the variations in their amplitudes and the atmospheric circulation, including the lower altitudes of the middle atmosphere.

AB - Numerical modeling of changes in the zonal circulation and amplitudes of stationary planetary waves are performed with an accounting for the impact of solar activity variations on the thermosphere. A thermospheric version of the Middle/Upper Atmosphere Model (MUAM) is used to calculate the circulation in the middle and upper atmosphere at altitudes up to 300 km from the Earth’s surface. Different values of the solar radio emission flux in the thermosphere are specified at a wavelength of 10.7 cm to take into account the solar activity variations. The ionospheric conductivities and their variations in latitude, longitude, and time are taken into account. The calculations are done for the January–February period and the conditions of low, medium, and high solar activity. It was shown that, during high-activity periods, the zonal wind velocities increases at altitudes exceeding 150 km and decreases in the lower layers. The amplitudes of planetary waves at high solar activity with respect to the altitude above 120 km or below 100 km, respectively, are smaller or larger than those at low activity. These differences correspond to the calculated changes in the refractive index of the atmosphere for stationary planetary waves and the Eliassen–Palm flux. Changes in the conditions for the propagation and reflection of stationary planetary waves in the thermosphere may influence the variations in their amplitudes and the atmospheric circulation, including the lower altitudes of the middle atmosphere.

KW - MIDDLE ATMOSPHERE

KW - NUMERICAL-SIMULATION

KW - NORTHERN-HEMISPHERE

KW - LOWER THERMOSPHERE

KW - OROGRAPHIC WAVES

KW - CIRCULATION

KW - TROPOSPHERE

KW - CYCLE

KW - INHOMOGENEITIES

KW - DISTURBANCES

UR - http://www.scopus.com/inward/record.url?scp=85045393767&partnerID=8YFLogxK

U2 - 10.1134/S001679321802010X

DO - 10.1134/S001679321802010X

M3 - Article

VL - 58

SP - 281

EP - 289

JO - Geomagnetism and Aeronomy

JF - Geomagnetism and Aeronomy

SN - 0016-7932

IS - 2

ER -