Lidar Study of the Thermal Regime of the Middle Atmosphere over Tomsk in 2023–2024

A chemistry-climate model of the lower and middle atmosphere has been used to estimate the sensitivity of the atmospheric gas composition to the rate of thunderstorm production of nitrogen oxides at upper tropospheric and lower stratospheric altitudes. The impact that nitrogen oxides produced by lightning have on the atmospheric gas composition is treated as a subgrid-scale process and included in the model parametrically. The natural uncertainty in the global production rate of nitrogen oxides in lightning flashes was specified within limits from 2 to 20 Tg N/year. Results of the model experiments have shown that, due to the variability of thunderstorm-produced nitrogen oxides, their concentration in the upper troposphere and lower stratosphere can vary by a factor of 2 or 3, which, given the influence of nitrogen oxides on ozone and other gases, creates the potential for a strong perturbation of the atmospheric gas composition and thermal regime. Model calculations have shown the strong sensitivity of ozone and the OH hydroxyl to the amount of lightning nitrogen oxides at different atmospheric altitudes. These calculations demonstrate the importance of nitrogen oxides of thunderstorm origin for the balance of atmospheric odd ozone and gases linked to it, such as ozone and hydroxyl radicals. Our results demonstrate that one important task is to raise the accuracy of estimates of the rate of nitrogen oxide production by lightning discharges and to use physical parametrizations that take into account the local lightning effects and feedbacks arising in this case rather than climatological data in models of the gas composition and general circulation of the atmosphere.

Polarization relations for mesoscale stationary orographic waves (MSOWs) and formulas for calculating vertical profiles of the total vertical flux of wave energy and amplitudes of horizontal speed are obtained by taking account the rotation of the atmosphere. Expressions are derived for the total wave heat flux, accelerations of the mean flow, and heat influxes generated by MSOWs. Calculations of the characteristics of MSOWs propagating in the atmosphere from the surface to the lower thermosphere are made. It was shown that MSOWs may significantly affect the circulation and thermal regime of the middle and upper atmosphere.

At the present time, lidar technologies are widely used in studies of the thermal regime of the middle atmosphere. Such studies at the Institute of Atmospheric Optics SB RAS began in 1994 in a monitoring mode and are ongoing. Particular attention is paid to the study of sudden disturbances in the middle stratosphere caused by winter stratospheric warming (SW). The earlier results obtained on this topic can be found in [1,2]. This paper presents studies of the vertical distribution of temperature over Tomsk during stratospheric warming in 2016-2020.

Processing and analysis of long-term series of vertical temperature distributions in the middle atmosphere (in the altitude range of 15–60 km) over Tomsk, which were obtained on the basis of routine measurements at the lidar station of the Zuev Institute of Atmospheric Optics of the Siberian Branch of the Russian Academy of Sciences for the period 2010–2020, have been performed. Based on the experimental data, regional features of the intra- and inter-annual variability of the thermal state of the middle atmosphere over Western Siberia have been revealed, and a vertical temperature distribution in the middle atmosphere that is more appropriate to the real conditions of the region has been proposed.

The radiative energy budget of the middle atmosphere and its parameterization in general circulation models

At present, lidar technologies are widely used in studies of the thermal regime of the middle atmosphere. Such studies in the monitoring mode began at the Institute of Atmospheric Optics of the Siberian Branch of the Russian Academy of Sciences in 1994 and are ongoing. Special attention is paid to the study of appearance of sudden disturbances in the middle stratosphere caused by winter stratospheric warmings (SW). The results obtained in this field of research can be found in [1]. This article presents studies of the vertical temperature distribution over Tomsk during the disturbed and calm periods of 2020, including the winters of 2019/20 and 2020/21.

The paper presents the results of lidar studies of the thermal regime of the middle atmosphere over Tomsk for 2024. It should be noted that such studies in the monitoring mode at the Institute of Atmospheric Optics SB RAS were started in 1994 and are currently ongoing. Particular attention is paid to studying the manifestation of sudden disturbances in the stratosphere caused by winter stratospheric warmings

Radiative cooling of the 30–110 km atmospheric layer

Magnetopause position as an important index of the space weather

At present, lidar technologies are widely used in studies of the thermal regime of the middle atmosphere. Such studies in the monitoring mode began at the Institute of Atmospheric Optics of the Siberian Branch of the Russian Academy of Sciences in 1994 and are ongoing. Special attention is paid to the study of appearance of sudden disturbances in the middle stratosphere caused by winter stratospheric warmings (SW). The results obtained in this field of research can be found in [1]. This article presents studies of the vertical temperature distribution over Tomsk during the disturbed and calm periods of 2020, including the winters of 2020/21 and 2021/22.

The paper presents the results of lidar studies of the behavior of the thermal regime of the middle atmosphere over Tomsk in the period for 2022. Note that such studies in the monitoring mode at the Institute of Atmospheric Optics SB RAS began in 1994 and are currently ongoing. Particular attention is paid to studying the manifestation of sudden disturbances in the stratosphere caused by winter stratospheric warming (SW). A description of lidar technology for studying the middle atmosphere and the results obtained on this topic in recent years can be found in works [1–8]. The indicated observation period covers periods of disturbed (SP winters 2021/22 and 2022/23), calm (summer) and transitional (spring, autumn) states of the middle atmosphere. Based on the accumulated experimental material, a number of features of the intra-annual dynamics of the thermal regime of the stratosphere for the region of Western Siberia have been established. Thus, winter stratospheric warming occurs annually from November to March, and for the long period of the year April – November, in the vast majority of cases, the vertical temperature distribution is in good agreement with the CIRA-86 model distribution. As primary information for analyzing the observation results for 2022, a data array of 93 total signals accumulated on individual nights was used. The interval of sounded heights extended from 10 to 70 km, the spatial resolution was 192 m. Reception of lidar signals was carried out in the photopulse counting mode with accumulation of 12×10412×104 launches of laser pulses (accumulation time – about two hours per night). Observations were carried out at night under cloudless sky conditions. В работе представлены результаты лидарных исследований поведения термического режима средней атмосферы над Томском в период за 2022 г. Отметим, что такие исследования в мониторинговом режиме в институте оптики атмосферы СО РАН были начаты с 1994 года и продолжаются в настоящее время. Особое внимание уделяется изучению проявления внезапных возмущений в стратосфере, вызываемых зимними стратосферными потеплениями (СП). С описанием лидарной технологии по исследованию средней атмосферы и полученными по данной тематике результатами за последние годы можно ознакомиться в работах [1–8]. Указанный период наблюдений охватывает периоды возмущенного (СП зимы 2021/22 и 2022/23 гг.), спокойного (лето) и переходного (весна, осень) состояния средней атмосферы. На основании накопленного экспериментального материала установлен ряд особенностей внутригодовой динамики термического режима стратосферы для региона Западной Сибири. Так, зимнее стратосферное потепление происходит ежегодно с ноября по март, а для длительного периода года апрель — ноябрь в подавляющем большинстве случаев вертикальное распределение температуры хорошо согласуется с модельным распределением CIRA-86. В качестве первичной информации для анализа результатов наблюдений за 2022 г. использовался массив данных из 93 суммарных сигналов, накопленных в отдельные ночи. Интервал зондируемых высот простирался от 10 до 70 км., пространственное разрешение составляло 192 м. Прием лидарных сигналов велся в режиме счета фотоимпульсов с накоплением по 12×10412×104 запускам лазерных импульсов (время накопления — около двух часов за ночь). Наблюдения проводились в ночное врем суток в условиях безоблачного неба.

The results of lidar studies of the thermal regime of the middle atmosphere over Tomsk in 2022 are presented. Such studies in the monitoring regime have been started at the Institute of Atmospheric Optics SB RAS in 1994 and are currently continuing. Special attention is paid to the study of the manifestation of sudden disturbances in the stratosphere caused by winter stratospheric warming (SW). The results obtained on this topic in recent years can be found in [1]. The specified observation period covers the periods of disturbed (2021/22 and 2022/23 winter SW), calm (summer) and transitional (spring, autumn) conditions of the middle atmosphere.