Pub Date : 2023-12-25DOI: 10.1134/s0001433823060117
O. A. Solenaya, E. A. Shishov, O. G. Chkhetiani, G. V. Azizyan, V. M. Koprov
Abstract
Synchronous measurements of vorticity and velocity in the boundary layer of the atmosphere were carried out using the original three-component acoustic circulator developed at the Obukhov Institute of Physical Physics (IAP) in 2019–2020. The measurements were carried out in summer at the Tsimlyansk scientific station (in 2021 and 2022) at heights of 1.75 and 30 m. For different realizations, turbulent helicity has negative values on average, which is possibly due to the presence of local (breeze) winds. The spectra of turbulent helicity exhibit a slope close to –5/3, which corresponds to the transfer of helicity along the spectrum towards small scales (direct cascade). Spectrum slopes of –4/3 are also observed, as well as, in the low-frequency region, –1, associated with the convective component, wind shear, and submesoscale structures. The components of the turbulent vortex flow are calculated. The helicity values agree with the previously measured and theoretical estimates obtained for neutral conditions.
{"title":"On Turbulent Helicity in the Surface Layer of the Atmosphere","authors":"O. A. Solenaya, E. A. Shishov, O. G. Chkhetiani, G. V. Azizyan, V. M. Koprov","doi":"10.1134/s0001433823060117","DOIUrl":"https://doi.org/10.1134/s0001433823060117","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Synchronous measurements of vorticity and velocity in the boundary layer of the atmosphere were carried out using the original three-component acoustic circulator developed at the Obukhov Institute of Physical Physics (IAP) in 2019–2020. The measurements were carried out in summer at the Tsimlyansk scientific station (in 2021 and 2022) at heights of 1.75 and 30 m. For different realizations, turbulent helicity has negative values on average, which is possibly due to the presence of local (breeze) winds. The spectra of turbulent helicity exhibit a slope close to –5/3, which corresponds to the transfer of helicity along the spectrum towards small scales (direct cascade). Spectrum slopes of –4/3 are also observed, as well as, in the low-frequency region, –1, associated with the convective component, wind shear, and submesoscale structures. The components of the turbulent vortex flow are calculated. The helicity values agree with the previously measured and theoretical estimates obtained for neutral conditions.</p>","PeriodicalId":54911,"journal":{"name":"Izvestiya Atmospheric and Oceanic Physics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139056337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-08DOI: 10.1134/s0001433823140062
M. Yu. Bardin, T. V. Platova, O. F. Samokhina
Abstract
Fluctuations in the frequency of cyclones in various regions of the Northern Hemisphere (NH) temperate latitudes on time scales of the order of decades are analyzed in connection with changes in the indices of the leading modes of atmospheric circulation and changes in the zonal transport intensity in individual latitudinal zones. The possible manifestation in cyclone statistics of the well-known thesis about the displacement of storm tracks during warming in the direction of high latitudes is discussed. It is shown that, in general, for the NH temperate latitudes in winter, long-period changes in the frequency of cyclones are irregular fluctuations with scales of several decades, without a visible trend. In summer, the interdecade changes are weakly expressed, but there is a noticeable trend that is significant at the 5% level. In the northern and southern parts of the North Atlantic (NA) in winter, changes in frequency contain significant antiphase components with a period of about 10 years, which correlate well with changes in the North Atlantic Oscillation (NAO) index (the correlation is positive in the northern half; the coefficients are significant at the 0.1% level). Long-period changes in the frequency of cyclones in the North Pacific are generally similar to (but in the opposite phase of) changes in the North Pacific Index by Trenberth and Hurrell. Based on the analysis of a linear regression model, it was found that a significant contribution to changes in the frequency of cyclones in the regions of northern Europe–Western Siberia and the north of ER (ER) in the winter season was made by the circulation modes of the Atlantic–European sector: SCAND, NAO, East Atlantic mode EAM, EAWR (but the EAWR mode contribution is insignificant for the north of Europe–Western Siberia). In summer, for the north of ER and Western Siberia, a significant contribution was made by the SCAND and EAWR circulation modes. An analysis of concomitant changes in zonal wind speed at 700 hPa in the area of the main storm tracks in winter revealed that, for the hemisphere as a whole (0°–360°) in the latitude zone 45°–55° N, as well as in the zone 55°–65° N, changes in zonal wind are determined mainly by changes in the frequency of cyclones in the northern part of the NA and closely follow changes in the NAO. However, in more southern latitudes (35°–45° N), changes in the hemispheric zonal wind are observed, similar to long-period changes in the North Pacific Index in antiphase, the nature of which is unclear (since they do not appear in the Pacific sector itself). The shift of storm tracks to higher latitudes, expected with warming, is observed only for the northern branch of the Atlantic storm track during periods of NAO growth between 1960 and the mid-1990s and after 2010. In general, for the period since 1976, there has been an insignificant trend of about 0.07° latitude per decade.
{"title":"Long-Period Changes in the Frequency of Cyclones in the Northern Hemisphere Temperate Latitudes","authors":"M. Yu. Bardin, T. V. Platova, O. F. Samokhina","doi":"10.1134/s0001433823140062","DOIUrl":"https://doi.org/10.1134/s0001433823140062","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Fluctuations in the frequency of cyclones in various regions of the Northern Hemisphere (NH) temperate latitudes on time scales of the order of decades are analyzed in connection with changes in the indices of the leading modes of atmospheric circulation and changes in the zonal transport intensity in individual latitudinal zones. The possible manifestation in cyclone statistics of the well-known thesis about the displacement of storm tracks during warming in the direction of high latitudes is discussed. It is shown that, in general, for the NH temperate latitudes in winter, long-period changes in the frequency of cyclones are irregular fluctuations with scales of several decades, without a visible trend. In summer, the interdecade changes are weakly expressed, but there is a noticeable trend that is significant at the 5% level. In the northern and southern parts of the North Atlantic (NA) in winter, changes in frequency contain significant antiphase components with a period of about 10 years, which correlate well with changes in the North Atlantic Oscillation (NAO) index (the correlation is positive in the northern half; the coefficients are significant at the 0.1% level). Long-period changes in the frequency of cyclones in the North Pacific are generally similar to (but in the opposite phase of) changes in the North Pacific Index by Trenberth and Hurrell. Based on the analysis of a linear regression model, it was found that a significant contribution to changes in the frequency of cyclones in the regions of northern Europe–Western Siberia and the north of ER (ER) in the winter season was made by the circulation modes of the Atlantic–European sector: SCAND, NAO, East Atlantic mode EAM, EAWR (but the EAWR mode contribution is insignificant for the north of Europe–Western Siberia). In summer, for the north of ER and Western Siberia, a significant contribution was made by the SCAND and EAWR circulation modes. An analysis of concomitant changes in zonal wind speed at 700 hPa in the area of the main storm tracks in winter revealed that, for the hemisphere as a whole (0°–360°) in the latitude zone 45°–55° N, as well as in the zone 55°–65° N, changes in zonal wind are determined mainly by changes in the frequency of cyclones in the northern part of the NA and closely follow changes in the NAO. However, in more southern latitudes (35°–45° N), changes in the hemispheric zonal wind are observed, similar to long-period changes in the North Pacific Index in antiphase, the nature of which is unclear (since they do not appear in the Pacific sector itself). The shift of storm tracks to higher latitudes, expected with warming, is observed only for the northern branch of the Atlantic storm track during periods of NAO growth between 1960 and the mid-1990s and after 2010. In general, for the period since 1976, there has been an insignificant trend of about 0.07° latitude per decade.</p>","PeriodicalId":54911,"journal":{"name":"Izvestiya Atmospheric and Oceanic Physics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138556019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-08DOI: 10.1134/s0001433823140049
M. Yu. Bardin
Abstract
This work is part of a study on the impact of black carbon (BC) transfer from various sources to the Arctic on climate change in the region. The main objectives are to develop software for analyzing the Lagrangian transport of air particles; assessing the deposition of aerosol particles by precipitation and the concentration of particles in the atmosphere; and obtaining, for specific conditions of atmospheric circulation during severe fires in the years of maximum reduction in the Arctic sea ice area, estimates of the relative residence time of air particles emitted by these fires over the Arctic Basin (AB), as well as the proportion of BC deposited in the AB from fires. This software package contains a module for calculating Lagrangian trajectories from a 4-dimensional wind array (u, v, ω, t), which contains horizontal wind components and an analog of vertical speed available from reanalysis, as well as modules for the postprocessing of the found trajectories, which allow us to obtain in a given area the residence time estimates, 3-dimensional BC concentration, and BC deposition on the surface, also using reanalysis data and some empirical constants. Since the main decrease in the Arctic sea ice area occurred in 2 years, 2007 and 2012, it was supposed to analyze the fires of these years; however, in 2007, there were no great fires, and in 2012 one fire was much larger than the others (K-217, March–June). This fire was chosen for the experiments: several sets of trajectories were obtained for it, corresponding to various options for choosing the initial conditions, and estimates were obtained for the fraction of trajectories that passed over the Arctic basin, the time spent there, and the fraction of BC deposited in the AB. Together, these estimates led to the conclusion that Siberian fires can hardly be the leading cause of the accelerated melting of Arctic sea ice.
摘要 这项工作是关于黑碳（BC）从各种来源转移到北极对该地区气候变化的影响的研究的一部分。主要目的是开发分析空气粒子拉格朗日传输的软件；评估降水造成的气溶胶粒子沉积和大气中的粒子浓度；在北极海冰面积减少最多的年份，针对严重火灾期间大气环流的特定条件，估算这些火灾排放的空气粒子在北极盆地（AB）上空的相对停留时间，以及火灾造成的黑碳沉积在北极盆地的比例。该软件包包含一个从四维风阵列（u、v、ω、t）计算拉格朗日轨迹的模块，其中包含水平风分量和可从再分析中获得的垂直速度模拟量；还包含对找到的轨迹进行后处理的模块，使我们能够在给定区域内获得停留时间估计值、三维 BC 浓度和 BC 在地表的沉积量，同样也可使用再分析数据和一些经验常数。由于北极海冰面积的主要减少发生在 2007 年和 2012 年这两年，因此本应对这两年的火灾进行分析；然而，2007 年没有发生大火，而 2012 年有一场火灾（K-217，3 月至 6 月）比其他火灾大得多。实验选择了这场大火：根据不同的初始条件选择，获得了几组火灾轨迹，并估算了经过北极盆地的轨迹比例、在北极盆地停留的时间以及沉积在北极盆地的 BC 比例。这些估算结果共同得出结论，西伯利亚大火很难成为北极海冰加速融化的主要原因。
{"title":"Long-Range Atmospheric Transport of Black Carbon from Severe Forest Fires in Siberia to the Arctic Basin","authors":"M. Yu. Bardin","doi":"10.1134/s0001433823140049","DOIUrl":"https://doi.org/10.1134/s0001433823140049","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>This work is part of a study on the impact of black carbon (BC) transfer from various sources to the Arctic on climate change in the region. The main objectives are to develop software for analyzing the Lagrangian transport of air particles; assessing the deposition of aerosol particles by precipitation and the concentration of particles in the atmosphere; and obtaining, for specific conditions of atmospheric circulation during severe fires in the years of maximum reduction in the Arctic sea ice area, estimates of the relative residence time of air particles emitted by these fires over the Arctic Basin (AB), as well as the proportion of BC deposited in the AB from fires. This software package contains a module for calculating Lagrangian trajectories from a 4-dimensional wind array (<i>u</i>, <i>v</i>, ω, <i>t</i>), which contains horizontal wind components and an analog of vertical speed available from reanalysis, as well as modules for the postprocessing of the found trajectories, which allow us to obtain in a given area the residence time estimates, 3-dimensional BC concentration, and BC deposition on the surface, also using reanalysis data and some empirical constants. Since the main decrease in the Arctic sea ice area occurred in 2 years, 2007 and 2012, it was supposed to analyze the fires of these years; however, in 2007, there were no great fires, and in 2012 one fire was much larger than the others (K-217, March–June). This fire was chosen for the experiments: several sets of trajectories were obtained for it, corresponding to various options for choosing the initial conditions, and estimates were obtained for the fraction of trajectories that passed over the Arctic basin, the time spent there, and the fraction of BC deposited in the AB. Together, these estimates led to the conclusion that Siberian fires can hardly be the leading cause of the accelerated melting of Arctic sea ice.</p>","PeriodicalId":54911,"journal":{"name":"Izvestiya Atmospheric and Oceanic Physics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138556184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-08DOI: 10.1134/s0001433823140013
G. V. Alekseev, A. E. Vyazilova, N. E. Kharlanenkova
Abstract
It has been previously shown that atmospheric and oceanic heat and moisture transfers play an important role in the development of Arctic warming, and ocean surface temperature anomalies at low latitudes have a significant effect on the formation of transfers. Atmospheric circulation, which transports heat, moisture and precipitation, also affects climatic conditions in the catchment areas of the three main Siberian rivers—the Ob, Yenisei, and Lena—the flow of which is approximately half of the annual average inflow of river water into the Arctic Ocean. According to reanalyses and archival data for 1979–2019, air temperature and precipitation in the Ob, Lena, and Yenisei catchment areas are increasing. The greatest increase in precipitation is recorded in the spring months. There is also a maximum positive trend in air temperature in the spring months (March and April). To assess the impact of low latitudes on changes in climatic conditions in the catchment areas, data from ERA5, HadISST reanalyses, and the GPCC project precipitation gridded gauge-analysis data are used. Based on the average monthly surface air temperature at the nodes of the geographic grid in the Northern Hemisphere, the indices of zonal, meridional, and general circulation are calculated. To determine the relationships between indices and climatic parameters, the methods of multivariate cross-correlation analysis are used. It has been found that zonal atmospheric transfers have a significant impact on climatic conditions most of all in the cold part of the year, especially in November and March. In summer, the increase in zonal circulation is accompanied by a decrease in air temperature in the catchment areas, and meridional transfers increase the temperature. The greatest influence of the meridional transport is noted in spring and summer. Climate changes at low latitudes have the greatest effect in autumn on meridional transport in the spring season and on zonal transport in the cold part of the year, especially in March, with a delay of 2 years. The influence of low latitudes on climatic conditions in water catchments is presented in the form of graphs of correlations of climatic parameters and circulation indices on a generalized scheme.
{"title":"Influence of Low Latitudes on Climatic Conditions in the Water Catchment Area of the Main Siberian Rivers","authors":"G. V. Alekseev, A. E. Vyazilova, N. E. Kharlanenkova","doi":"10.1134/s0001433823140013","DOIUrl":"https://doi.org/10.1134/s0001433823140013","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>It has been previously shown that atmospheric and oceanic heat and moisture transfers play an important role in the development of Arctic warming, and ocean surface temperature anomalies at low latitudes have a significant effect on the formation of transfers. Atmospheric circulation, which transports heat, moisture and precipitation, also affects climatic conditions in the catchment areas of the three main Siberian rivers—the Ob, Yenisei, and Lena—the flow of which is approximately half of the annual average inflow of river water into the Arctic Ocean. According to reanalyses and archival data for 1979–2019, air temperature and precipitation in the Ob, Lena, and Yenisei catchment areas are increasing. The greatest increase in precipitation is recorded in the spring months. There is also a maximum positive trend in air temperature in the spring months (March and April). To assess the impact of low latitudes on changes in climatic conditions in the catchment areas, data from ERA5, HadISST reanalyses, and the GPCC project precipitation gridded gauge-analysis data are used. Based on the average monthly surface air temperature at the nodes of the geographic grid in the Northern Hemisphere, the indices of zonal, meridional, and general circulation are calculated. To determine the relationships between indices and climatic parameters, the methods of multivariate cross-correlation analysis are used. It has been found that zonal atmospheric transfers have a significant impact on climatic conditions most of all in the cold part of the year, especially in November and March. In summer, the increase in zonal circulation is accompanied by a decrease in air temperature in the catchment areas, and meridional transfers increase the temperature. The greatest influence of the meridional transport is noted in spring and summer. Climate changes at low latitudes have the greatest effect in autumn on meridional transport in the spring season and on zonal transport in the cold part of the year, especially in March, with a delay of 2 years. The influence of low latitudes on climatic conditions in water catchments is presented in the form of graphs of correlations of climatic parameters and circulation indices on a generalized scheme.</p>","PeriodicalId":54911,"journal":{"name":"Izvestiya Atmospheric and Oceanic Physics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138556680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-08DOI: 10.1134/s0001433823140086
E. I. Khlebnikova, I. M. Shkolnik, Yu. L. Rudakova
Abstract
Possibilities of using the basic technology of probabilistic scenario forecasting of the regional climate to obtain detailed estimates of future changes in applied indicators of the thermal regime in the territory of federal districts and individual subjects of the Russian Federation are considered. Probabilistic ensemble estimates of future changes are presented for climatic indicators such as seasonal extremes of air temperature for a given averaging period, the sum of active temperatures, energy consumption indices for cold and warm seasons, and other characteristics of intra-annual periods with air temperatures above/below threshold values. The changes in the considered parameters of the thermal regime have been analyzed. It is shown that the main features of changes expected by the middle of the 21st century detected by the results of modeling over most of the territory of Russia are well manifested based on the observational data in the interval 1961–2020.
{"title":"Probabilistic Estimates of Variations in Applied Indicators of the Thermal Regime for the Adaptation to Climate Change in Russia","authors":"E. I. Khlebnikova, I. M. Shkolnik, Yu. L. Rudakova","doi":"10.1134/s0001433823140086","DOIUrl":"https://doi.org/10.1134/s0001433823140086","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Possibilities of using the basic technology of probabilistic scenario forecasting of the regional climate to obtain detailed estimates of future changes in applied indicators of the thermal regime in the territory of federal districts and individual subjects of the Russian Federation are considered. Probabilistic ensemble estimates of future changes are presented for climatic indicators such as seasonal extremes of air temperature for a given averaging period, the sum of active temperatures, energy consumption indices for cold and warm seasons, and other characteristics of intra-annual periods with air temperatures above/below threshold values. The changes in the considered parameters of the thermal regime have been analyzed. It is shown that the main features of changes expected by the middle of the 21st century detected by the results of modeling over most of the territory of Russia are well manifested based on the observational data in the interval 1961–2020.</p>","PeriodicalId":54911,"journal":{"name":"Izvestiya Atmospheric and Oceanic Physics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138556180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-08DOI: 10.1134/s0001433823140025
G. V. Alekseev, N. E. Kharlanenkova, A. E. Vyazilova
Abstract
An increase in warming in the Arctic relative to the rest of the Northern Hemisphere or the globe continues attracting attention, despite the large amount of research being conducted. Possible causes of the Arctic amplification have been considered and continue to be discussed in many articles and reviews. In this article, for the first time, a quantitative assessment of the role of atmospheric transports in the formation of variability and trends in the mean near-surface air temperature (SAT) in the Arctic and at adjacent latitudes of the Northern Hemisphere is carried out and an analytical description of amplification in high latitudes is proposed. For the study, data from NCEP and ERA5 reanalyses for 1989–2020 and a representation of the set of events of air exchange between latitudes in a simple hemispheric atmospheric model under constant conditions at the boundaries, on the basis of which analytical expressions are obtained for the standard deviation ratios (SDRs) and temperature trends in neighboring areas. The degree of closeness between the empirical and model ratios of SDR and trends is taken as a contribution measure of air exchange to the increase in SDR and trends during warming. It has been found that the exchange between the polar and adjacent regions reaches lower latitudes as the polar region expands from 70° N up to 60° N. The latitude to which the polar air propagates on average decreases with the trend taken into account in the SDR, which confirms the effect of warming on the increase in air mass exchange. The model value of the increase in the average air temperature trend in the polar region of an isolated homogeneous atmosphere above the hemisphere relative to the trend in the adjacent region is determined by the ratio of their areas multiplied by the ratio of the trend determination coefficients. An increase in the temperature trend in the polar region of the real atmosphere, according to the NCEP and ERA5 reanalyses for 1989–2020, was compared with the model value, thereby assessing the contribution of air mass exchange to the increase in the temperature trend in the polar region. It was found that the exchange explains 54% of the increase in the air temperature trend (Arctic amplification) in the region of 90–60° N on average per year and 66% in the cold year part relative to the rest of the Northern Hemisphere. If we take into account the established southern boundary of air mass exchange between the polar and adjacent regions, then the amplification of an air temperature trend in the area of 90–60° N relative to the trend in the adjacent area, with which the exchange of air masses occurs, will almost completely (by 93% on average per year) be the result of exchange and, in the area of 90°–70° N, it will mostly be the result of exchange (by 74% on average per year).
{"title":"Arctic Amplification: InterlatitudinaI Exchange Role in the Atmosphere","authors":"G. V. Alekseev, N. E. Kharlanenkova, A. E. Vyazilova","doi":"10.1134/s0001433823140025","DOIUrl":"https://doi.org/10.1134/s0001433823140025","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>An increase in warming in the Arctic relative to the rest of the Northern Hemisphere or the globe continues attracting attention, despite the large amount of research being conducted. Possible causes of the Arctic amplification have been considered and continue to be discussed in many articles and reviews. In this article, for the first time, a quantitative assessment of the role of atmospheric transports in the formation of variability and trends in the mean near-surface air temperature (SAT) in the Arctic and at adjacent latitudes of the Northern Hemisphere is carried out and an analytical description of amplification in high latitudes is proposed. For the study, data from NCEP and ERA5 reanalyses for 1989–2020 and a representation of the set of events of air exchange between latitudes in a simple hemispheric atmospheric model under constant conditions at the boundaries, on the basis of which analytical expressions are obtained for the standard deviation ratios (SDRs) and temperature trends in neighboring areas. The degree of closeness between the empirical and model ratios of SDR and trends is taken as a contribution measure of air exchange to the increase in SDR and trends during warming. It has been found that the exchange between the polar and adjacent regions reaches lower latitudes as the polar region expands from 70° N up to 60° N. The latitude to which the polar air propagates on average decreases with the trend taken into account in the SDR, which confirms the effect of warming on the increase in air mass exchange. The model value of the increase in the average air temperature trend in the polar region of an isolated homogeneous atmosphere above the hemisphere relative to the trend in the adjacent region is determined by the ratio of their areas multiplied by the ratio of the trend determination coefficients. An increase in the temperature trend in the polar region of the real atmosphere, according to the NCEP and ERA5 reanalyses for 1989–2020, was compared with the model value, thereby assessing the contribution of air mass exchange to the increase in the temperature trend in the polar region. It was found that the exchange explains 54% of the increase in the air temperature trend (Arctic amplification) in the region of 90–60° N on average per year and 66% in the cold year part relative to the rest of the Northern Hemisphere. If we take into account the established southern boundary of air mass exchange between the polar and adjacent regions, then the amplification of an air temperature trend in the area of 90–60° N relative to the trend in the adjacent area, with which the exchange of air masses occurs, will almost completely (by 93% on average per year) be the result of exchange and, in the area of 90°–70° N, it will mostly be the result of exchange (by 74% on average per year).</p>","PeriodicalId":54911,"journal":{"name":"Izvestiya Atmospheric and Oceanic Physics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138556679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-08DOI: 10.1134/s0001433823140037
M. A. Aleshina, V. A. Semenov
Abstract
A study has been made of changes in some characteristics of daily precipitation in Russia for the winter and summer seasons in the 20th and 21st centuries using Coupled Model Intercomparison Project Phase 6 (CMIP6) climate models. In the modern period, model data are compared with data from meteorological stations and ERA5 reanalysis. For winter and summer, changes in mean seasonal precipitation, the number of days with precipitation, and the frequency of extreme precipitation are analyzed. For the modern period 1991–2020, according to empirical data, in winter on the territory of Russia, a significant increase in seasonal precipitation amounts and the frequency of days with extreme precipitation on the Far East coast and in the central part of European Russia (ER) are detected. A decrease in the frequency of days with precipitation at most meteorological stations in Russia by 4–6 days/10 years is also noted. In summer, an increase in precipitation amounts and the frequency of days with precipitation is found in Western Siberia and on the coasts of the Sea of Okhotsk and the Pacific Ocean. A decrease in the amount and frequency of precipitation is obtained for southern ER and the south of Eastern Siberia. Climate models, on average for the ensemble, show an increase in the relative amounts of precipitation and the extreme precipitation frequency over most of the Russia territory in winter, and these trends may intensify in the coming decades. In summer, on the contrary, for southern ER, as a whole, there is a slight decrease in the seasonal precipitation totals and the number of days with precipitation. However, strong intermodel differences, especially in the summer season, do not allow us to draw unambiguous conclusions about changes in precipitation characteristics in Russia in the next 30 years. By the end of the 21st century, changes will become more pronounced. For example, in ER and northern Siberia, a noticeable increase in winter precipitation amounts and the frequency of extreme precipitation may occur. By the end of the 21st century, a slight decrease in the precipitation totals and the number of days with precipitation is possible in summer in ER.
{"title":"Changes in Precipitation Characteristics over Russia in the 20th and 21st Centuries According to CMIP6 Model Ensemble Data","authors":"M. A. Aleshina, V. A. Semenov","doi":"10.1134/s0001433823140037","DOIUrl":"https://doi.org/10.1134/s0001433823140037","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A study has been made of changes in some characteristics of daily precipitation in Russia for the winter and summer seasons in the 20th and 21st centuries using Coupled Model Intercomparison Project Phase 6 (CMIP6) climate models. In the modern period, model data are compared with data from meteorological stations and ERA5 reanalysis. For winter and summer, changes in mean seasonal precipitation, the number of days with precipitation, and the frequency of extreme precipitation are analyzed. For the modern period 1991–2020, according to empirical data, in winter on the territory of Russia, a significant increase in seasonal precipitation amounts and the frequency of days with extreme precipitation on the Far East coast and in the central part of European Russia (ER) are detected. A decrease in the frequency of days with precipitation at most meteorological stations in Russia by 4–6 days/10 years is also noted. In summer, an increase in precipitation amounts and the frequency of days with precipitation is found in Western Siberia and on the coasts of the Sea of Okhotsk and the Pacific Ocean. A decrease in the amount and frequency of precipitation is obtained for southern ER and the south of Eastern Siberia. Climate models, on average for the ensemble, show an increase in the relative amounts of precipitation and the extreme precipitation frequency over most of the Russia territory in winter, and these trends may intensify in the coming decades. In summer, on the contrary, for southern ER, as a whole, there is a slight decrease in the seasonal precipitation totals and the number of days with precipitation. However, strong intermodel differences, especially in the summer season, do not allow us to draw unambiguous conclusions about changes in precipitation characteristics in Russia in the next 30 years. By the end of the 21st century, changes will become more pronounced. For example, in ER and northern Siberia, a noticeable increase in winter precipitation amounts and the frequency of extreme precipitation may occur. By the end of the 21st century, a slight decrease in the precipitation totals and the number of days with precipitation is possible in summer in ER.</p>","PeriodicalId":54911,"journal":{"name":"Izvestiya Atmospheric and Oceanic Physics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138556024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-08DOI: 10.1134/s0001433823140098
L. K. Kleshchenko, E. Ya. Rankova
Abstract
In this article, episodes of potential blocking in the Northern Hemisphere (40°–75° N) are determined based on the analysis of deviations of the H500 geopotential at the nodes of a regular geographic grid from their midlatitude values. The cumulative calendar season/year duration of blocking episodes is considered as the TD blocking index. The spatial distribution of seasonal/annual TD indices and their anomalies in 2020 are analyzed (up to 160 days). The highest values of the annual TD index in 2020 were observed on the European continent in the zone 50°–57.5° N (up to 160 days). Anomalies of the TD index in European Russia (ER) and in Western Siberia amounted to +30 days; in the northern regions of Eastern Siberia they lasted more than +40 days. In the Western Hemisphere, positive anomalies in the annual TD index were observed in the East Pacific Ocean south of 50° N (for more than +50 days). Negative anomalies covered the central regions of North America (up –80 days). According to estimates in active blocking sectors, in the first half of 2020, blocking in the European sector (10° W–60° E; 50°–65° N) was weakened relative to the multiyear average. In the summer and autumn seasons, positive anomalies of blocking indices were noted in this region. In the North American sector (100°–160° W; 50°–65° N), negative anomalies were observed in all seasons except for spring. Estimates of the linear trend of blocking indices at the nodes of the regular grid and in general in the latitudinal belt and its sectors were analyzed for 1949–2020 and 1976–2020. On average, negative trends prevailed in all seasons, but the spatial distribution of the trend coefficients varied from season to season. The trend of the annual duration of blocking episodes in the latitude zone 50°–65° N is 1.0 days/10 years and is statistically significant at a 1% level.
{"title":"Blocking Indices in the Northern Hemisphere: Assessments for 2020 and Trends of Long-Term Changes","authors":"L. K. Kleshchenko, E. Ya. Rankova","doi":"10.1134/s0001433823140098","DOIUrl":"https://doi.org/10.1134/s0001433823140098","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>In this article, episodes of potential blocking in the Northern Hemisphere (40°–75° N) are determined based on the analysis of deviations of the H500 geopotential at the nodes of a regular geographic grid from their midlatitude values. The cumulative calendar season/year duration of blocking episodes is considered as the <i>TD</i> blocking index. The spatial distribution of seasonal/annual <i>TD</i> indices and their anomalies in 2020 are analyzed (up to 160 days). The highest values of the annual <i>TD</i> index in 2020 were observed on the European continent in the zone 50°–57.5° N (up to 160 days). Anomalies of the <i>TD</i> index in European Russia (ER) and in Western Siberia amounted to +30 days; in the northern regions of Eastern Siberia they lasted more than +40 days. In the Western Hemisphere, positive anomalies in the annual <i>TD</i> index were observed in the East Pacific Ocean south of 50° N (for more than +50 days). Negative anomalies covered the central regions of North America (up –80 days). According to estimates in active blocking sectors, in the first half of 2020, blocking in the European sector (10° W–60° E; 50°–65° N) was weakened relative to the multiyear average. In the summer and autumn seasons, positive anomalies of blocking indices were noted in this region. In the North American sector (100°–160° W; 50°–65° N), negative anomalies were observed in all seasons except for spring. Estimates of the linear trend of blocking indices at the nodes of the regular grid and in general in the latitudinal belt and its sectors were analyzed for 1949–2020 and 1976–2020. On average, negative trends prevailed in all seasons, but the spatial distribution of the trend coefficients varied from season to season. The trend of the annual duration of blocking episodes in the latitude zone 50°–65° N is 1.0 days/10 years and is statistically significant at a 1% level.</p>","PeriodicalId":54911,"journal":{"name":"Izvestiya Atmospheric and Oceanic Physics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138556303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-08DOI: 10.1134/s0001433823140050
M. Yu. Bardin, T. V. Platova
Abstract
The statistics, structure, and variability of large-scale cold waves in various latitudinal zones of European Russia (ER) in the winter and summer seasons are considered. The largest number of waves is observed in winter in the south of ER and in summer in the north. The contribution to the total seasonal duration of the longest waves (more than 12 days) is observed in winter in the north (>40%); in summer, waves of such duration are not observed in the center and south of ER. Winter cold waves in all zones are characterized by areas of negative temperature anomaly, covering almost the entire territory of Russia, with centers in the corresponding zone of the ER and extending eastward up to 140° E. Summer waves have a three-field structure with centers of cold over ER and the west of Western Siberia and over Yakutia, and a positive anomaly in the eastern part of Western Siberia and western Central Siberia. Circulation structures in the troposphere accompanying the cold waves and their role in the formation of temperature anomalies are discussed. In winter, the H500 geopotential fields during waves in the center and south of ER are characterized by a powerful ridge over the north of ER and the Scandinavian Peninsula (which corresponds to the Scandinavian atmospheric circulation mode) and a trough in the south of ER and Western Siberia. Cold waves in the northern zone occur with a crest in the Atlantic north and a trough in the south (the North Atlantic Oscillation (NAO) negative phase) and a trough in the north of ER. Summer cold waves in all zones are accompanied by a cutoff cyclone centered in the corresponding zone (slightly to the north for waves in ER south); a negative geopotential anomaly over ER corresponds to the negative phase of East Atlantic–West Russia (EAWR) mode. The seasonal wave duration series during the 20th to the first two decades of the 21st centuries exhibits pronounced long-term variability with time scales of about a decade and several decades. In summer, there has been a downward trend in the seasonal duration of cold waves in all ER zones since the mid-1970s, especially significant (in terms of contribution to overall variability) in the south. In winter, a downward (insignificant) trend is observed only for waves in the north. In the south and especially in the center, the total duration of cold waves increases from the 1990s to the end of 2000s. The connection between this behavior of the total duration of winter waves and changes in the Atlantic–European sector leading circulation modes is discussed.
{"title":"Cold Waves in European Russia: Structure, Circulation Conditions, and Changes in Seasonal Statistics","authors":"M. Yu. Bardin, T. V. Platova","doi":"10.1134/s0001433823140050","DOIUrl":"https://doi.org/10.1134/s0001433823140050","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The statistics, structure, and variability of large-scale cold waves in various latitudinal zones of European Russia (ER) in the winter and summer seasons are considered. The largest number of waves is observed in winter in the south of ER and in summer in the north. The contribution to the total seasonal duration of the longest waves (more than 12 days) is observed in winter in the north (>40%); in summer, waves of such duration are not observed in the center and south of ER. Winter cold waves in all zones are characterized by areas of negative temperature anomaly, covering almost the entire territory of Russia, with centers in the corresponding zone of the ER and extending eastward up to 140° E. Summer waves have a three-field structure with centers of cold over ER and the west of Western Siberia and over Yakutia, and a positive anomaly in the eastern part of Western Siberia and western Central Siberia. Circulation structures in the troposphere accompanying the cold waves and their role in the formation of temperature anomalies are discussed. In winter, the H500 geopotential fields during waves in the center and south of ER are characterized by a powerful ridge over the north of ER and the Scandinavian Peninsula (which corresponds to the Scandinavian atmospheric circulation mode) and a trough in the south of ER and Western Siberia. Cold waves in the northern zone occur with a crest in the Atlantic north and a trough in the south (the North Atlantic Oscillation (NAO) negative phase) and a trough in the north of ER. Summer cold waves in all zones are accompanied by a cutoff cyclone centered in the corresponding zone (slightly to the north for waves in ER south); a negative geopotential anomaly over ER corresponds to the negative phase of East Atlantic–West Russia (EAWR) mode. The seasonal wave duration series during the 20th to the first two decades of the 21st centuries exhibits pronounced long-term variability with time scales of about a decade and several decades. In summer, there has been a downward trend in the seasonal duration of cold waves in all ER zones since the mid-1970s, especially significant (in terms of contribution to overall variability) in the south. In winter, a downward (insignificant) trend is observed only for waves in the north. In the south and especially in the center, the total duration of cold waves increases from the 1990s to the end of 2000s. The connection between this behavior of the total duration of winter waves and changes in the Atlantic–European sector leading circulation modes is discussed.</p>","PeriodicalId":54911,"journal":{"name":"Izvestiya Atmospheric and Oceanic Physics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138556179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-08DOI: 10.1134/s0001433823140141
A. B. Uspensky
Abstract
A review of works of the last 20 years devoted to the development in our country and abroad of methods and means of measuring the concentration fields of long-lived carbon-containing greenhouse gases in the atmosphere—carbon dioxide CO2 and methane CH4—from satellites has been carried out. Physical and mathematical foundations for interpreting measurements from modern satellite spectrometers in the near-infrared and infrared spectral ranges are briefly reviewed. Information is provided on programs for the development of domestic and foreign satellite systems for monitoring the content of CO2 and CH4 in the atmosphere, as well as on ground-based observation networks, the data of which can be used for calibrating and validating satellite information products.
{"title":"Atmospheric Greenhouse Gas Distributions: Satellite-Based Measurements","authors":"A. B. Uspensky","doi":"10.1134/s0001433823140141","DOIUrl":"https://doi.org/10.1134/s0001433823140141","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A review of works of the last 20 years devoted to the development in our country and abroad of methods and means of measuring the concentration fields of long-lived carbon-containing greenhouse gases in the atmosphere—carbon dioxide CO<sub>2</sub> and methane CH<sub>4</sub>—from satellites has been carried out. Physical and mathematical foundations for interpreting measurements from modern satellite spectrometers in the near-infrared and infrared spectral ranges are briefly reviewed. Information is provided on programs for the development of domestic and foreign satellite systems for monitoring the content of CO<sub>2</sub> and CH<sub>4</sub> in the atmosphere, as well as on ground-based observation networks, the data of which can be used for calibrating and validating satellite information products.</p>","PeriodicalId":54911,"journal":{"name":"Izvestiya Atmospheric and Oceanic Physics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138556026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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