It has been shown that the abnormal rainfall in the catchment of the Amur river in 2013 had a mon... more It has been shown that the abnormal rainfall in the catchment of the Amur river in 2013 had a monsoon nature. The origin and evolution of the Asian monsoon (AM) from the region of its formation in the western Indian Ocean to the penetration to Northern Asia have been analyzed. It has been shown that the indices of the Indian Ocean dipole, El Niño, and the North Pacific indices were in phases that contributed not only to maximization of its intensity, but also to the fastest possible movement of the AM from the region of origin through the Indian subcontinent, Southeast Asia, and China to the Russian Far East. Due to the current composition of the climate indices in the Indian and Pacific oceans, the overwetted monsoon air mass brought the minimum possible loss of precipitation on its way to the final region. Increased monsoon precipitation in the vast catchment of the Amur river was facilitated by the fact that the Arctic Oscillation was in the negative phase, which led to the transfer of cold arctic air into the region. The latter circumstance influenced an increase in precipitation through the mechanism of accelerated condensation in humid air. Negative values of the North Pacific indices contributed to the development of blocking situations in the zonal current of temperate latitudes, which localized the zone of precipitation.
We present the results of an analysis of climatic series of global and regional cloudiness for 19... more We present the results of an analysis of climatic series of global and regional cloudiness for 1983-2009. The data were obtained as part of the ISCCP international satellite project. A technique of statistical time series analysis that includes a smoothing algorithm and wavelet analysis is described. Both methods are intended for the analysis of nonstationary series. According to the results of analysis, both global and regional cloudiness show a decrease of 2-6%. The greatest decrease is observed in the tropics and over the oceans, while the decrease is minimal over land. The correlation coefficient between the global cloud series on the one hand and the global air and ocean surface temperature series on the other hand reaches values between-0.84 and-0.86. The coefficient of determination that characterizes the regression accuracy for the prediction of global temperature variations based on the variations in the lower cloud cover in this case is 0.316.
Izvestiya, Atmospheric and Oceanic Physics, 2019, Vol. 55, No. 9, pp. 1182–1188, 2019
We propose using multiple regression to create a statistical model for describing climate change ... more We propose using multiple regression to create a statistical model for describing climate change under the influence of specified climate-forming factors. This model provides not only estimates of the temporal evolution of global temperature, but also a set of corresponding confidence intervals with a high level of statistical significance (probability). Eliminating the linear trend of climatic temperature series (CRUTEM) and atmospheric CO 2 concentration allows an objective quantitative assessment of the impact of natural factors on climate change. The global CRUTEM temperature responds quasi-synchronously to the fluctuations in the average surface temperature of the North Atlantic (AMO index); however, to changes in solar activity (Wolf numbers), it does so with a delay of approximately 15 years. The linear trend of increasing CO 2 concentration in the atmosphere explains almost all the interannual variability and reflects the linear trend of global temperature, but covers only part of its interannual variability.
Remote sensing data provided the major contribution to the sea surface temperature (SST) field an... more Remote sensing data provided the major contribution to the sea surface temperature (SST) field analysis during last several decades. Climate variability of the SST in Northern Atlantic is investigated by using an empirical orthogonal function (EOF) and fuzzy classification techniques. The leading EOF of the wintertime sea-level pressure (SLP) field is more strongly coupled to the surface atmosphere temperature (SAT) fluctuations over Europe than the NAO. Non-linear trend estimation technique was developed to detect an inter-annual variability of the SST, the SLP and the SAT. The SST had a tendency to dropping in interval from late forties to early seventies of last century. This tendency was changed to increasing in the middle of seventies and continued to the end of last century. It is in a good coherence with the SAT climate series in Europe.
The aim of this study is to classify circulation patterns in Atlantic-European sector and to reve... more The aim of this study is to classify circulation patterns in Atlantic-European sector and to reveal linkages between anomalies in pressure field over North Atlantic (e.g. NAO) and respective circulation pattern occurrence over continent on one hand and rain fields on other hand. Changes in atmospheric circulation over Europe during the past 50 years were examined using both objective (modes of low-frequency variability inferred by regression analysis and objective cluster classification of circulation types – fuzzy logic) and subjective (Hess-Brezowsky classification of weather types) methods. The grid monthly geopotential H700, wind zonal and meridional velocity components U850 and V850 as well as the surface atmosphere pressure (SAP), and precipitation fields acquired from NCEP/NCAR reanalysis dataset (for 1948-1998) were employed in this study. Joint regression analysis of and fuzzy logic classification of these fields was a basic to reveal major circulation regimes. The fuzzy se...
... Greenfelt, 1994). Large positive trends in the tropospheric ozone have been reported recently... more ... Greenfelt, 1994). Large positive trends in the tropospheric ozone have been reported recently in a number of studies (Staehelin & Schmid, 1991; Johnson & Isaksen, 1993; Kley et al, 1994; Oltmans & Levy, 1994). For instance ...
A statistical inversion method is first presented in support to the application of kernel-based B... more A statistical inversion method is first presented in support to the application of kernel-based BRDF (bi-directional reflectance distribution function) models for the calculation of the surface albedo. We present an operational procedure for the inversion of a kernel-driven BRDF model and further albedo retrieval to be applicable to the SEVIRI/MSG reflectance measurements. The processing steps applied to space-borne POLDER sensor data were as follows: (1) quality control, (2) accumulation of a priori information on model coefficients of directional hemispherical reflectance, (3) implementation of the BRDF model inversion methods based on the biased estimation instead of usual non-biased least solution, which has too big a variance in this case. The data control procedure consists both in filtering inputs of reflectance data and output of model coefficients based on analysis criteria determined by Fisher statistics. A multi-criteria procedure follows considering in particular the shape of the reflectance angular signature: (1) T-statistics, (2) the bowl shape index, (3) the dome shape index, (4) the white sky albedo (bi-hemispherical reflectance), (5) the black sky albedo variance (directional hemispherical reflectance). The procedure is applied to POLDER data corresponding to the 16 classes of IGBP land cover classification. The statistical results include mean values and covariance matrix for the spectral BRDF model coefficients.
An alternative approach to the conventional dynamic and photochemical models is presented to fore... more An alternative approach to the conventional dynamic and photochemical models is presented to forecast urban air pollutants operationally. It is well known that there are some practical difficulties, which prevent the necessary progress in the development of these models as a forecasting tool. A fuzzy logic based method has been developed here to study the impact of meteorological factors on the evolution of air pollutant levels and to describe them quantitatively. This method meets all requirements but needs substantial amount of observational data. The developed model is based on simulation of diurnal cycles of principal meteorological variables (wind speed and direction, solar irradiance and air temperature) and the corresponding diurnal patterns of various air pollutants (O3, NO2, NO, NOy). In addition, the spatial patterns of these parameters are also studied. Both temporal and spatial parameter distributions have been considered in order to investigate impacts of meteorological factors and they are incorporated into the models as state vectors in the multidimensional space. Here we suggest that most of the weather and air pollution phenomena could be simulated by sequences of its conservation inside some fuzzy sets and the transition from one fuzzy set to another. Therefore, the important key point here is the development of the transition rules.
It has been shown that the abnormal rainfall in the catchment of the Amur river in 2013 had a mon... more It has been shown that the abnormal rainfall in the catchment of the Amur river in 2013 had a monsoon nature. The origin and evolution of the Asian monsoon (AM) from the region of its formation in the western Indian Ocean to the penetration to Northern Asia have been analyzed. It has been shown that the indices of the Indian Ocean dipole, El Niño, and the North Pacific indices were in phases that contributed not only to maximization of its intensity, but also to the fastest possible movement of the AM from the region of origin through the Indian subcontinent, Southeast Asia, and China to the Russian Far East. Due to the current composition of the climate indices in the Indian and Pacific oceans, the overwetted monsoon air mass brought the minimum possible loss of precipitation on its way to the final region. Increased monsoon precipitation in the vast catchment of the Amur river was facilitated by the fact that the Arctic Oscillation was in the negative phase, which led to the transfer of cold arctic air into the region. The latter circumstance influenced an increase in precipitation through the mechanism of accelerated condensation in humid air. Negative values of the North Pacific indices contributed to the development of blocking situations in the zonal current of temperate latitudes, which localized the zone of precipitation.
We present the results of an analysis of climatic series of global and regional cloudiness for 19... more We present the results of an analysis of climatic series of global and regional cloudiness for 1983-2009. The data were obtained as part of the ISCCP international satellite project. A technique of statistical time series analysis that includes a smoothing algorithm and wavelet analysis is described. Both methods are intended for the analysis of nonstationary series. According to the results of analysis, both global and regional cloudiness show a decrease of 2-6%. The greatest decrease is observed in the tropics and over the oceans, while the decrease is minimal over land. The correlation coefficient between the global cloud series on the one hand and the global air and ocean surface temperature series on the other hand reaches values between-0.84 and-0.86. The coefficient of determination that characterizes the regression accuracy for the prediction of global temperature variations based on the variations in the lower cloud cover in this case is 0.316.
Izvestiya, Atmospheric and Oceanic Physics, 2019, Vol. 55, No. 9, pp. 1182–1188, 2019
We propose using multiple regression to create a statistical model for describing climate change ... more We propose using multiple regression to create a statistical model for describing climate change under the influence of specified climate-forming factors. This model provides not only estimates of the temporal evolution of global temperature, but also a set of corresponding confidence intervals with a high level of statistical significance (probability). Eliminating the linear trend of climatic temperature series (CRUTEM) and atmospheric CO 2 concentration allows an objective quantitative assessment of the impact of natural factors on climate change. The global CRUTEM temperature responds quasi-synchronously to the fluctuations in the average surface temperature of the North Atlantic (AMO index); however, to changes in solar activity (Wolf numbers), it does so with a delay of approximately 15 years. The linear trend of increasing CO 2 concentration in the atmosphere explains almost all the interannual variability and reflects the linear trend of global temperature, but covers only part of its interannual variability.
Remote sensing data provided the major contribution to the sea surface temperature (SST) field an... more Remote sensing data provided the major contribution to the sea surface temperature (SST) field analysis during last several decades. Climate variability of the SST in Northern Atlantic is investigated by using an empirical orthogonal function (EOF) and fuzzy classification techniques. The leading EOF of the wintertime sea-level pressure (SLP) field is more strongly coupled to the surface atmosphere temperature (SAT) fluctuations over Europe than the NAO. Non-linear trend estimation technique was developed to detect an inter-annual variability of the SST, the SLP and the SAT. The SST had a tendency to dropping in interval from late forties to early seventies of last century. This tendency was changed to increasing in the middle of seventies and continued to the end of last century. It is in a good coherence with the SAT climate series in Europe.
The aim of this study is to classify circulation patterns in Atlantic-European sector and to reve... more The aim of this study is to classify circulation patterns in Atlantic-European sector and to reveal linkages between anomalies in pressure field over North Atlantic (e.g. NAO) and respective circulation pattern occurrence over continent on one hand and rain fields on other hand. Changes in atmospheric circulation over Europe during the past 50 years were examined using both objective (modes of low-frequency variability inferred by regression analysis and objective cluster classification of circulation types – fuzzy logic) and subjective (Hess-Brezowsky classification of weather types) methods. The grid monthly geopotential H700, wind zonal and meridional velocity components U850 and V850 as well as the surface atmosphere pressure (SAP), and precipitation fields acquired from NCEP/NCAR reanalysis dataset (for 1948-1998) were employed in this study. Joint regression analysis of and fuzzy logic classification of these fields was a basic to reveal major circulation regimes. The fuzzy se...
... Greenfelt, 1994). Large positive trends in the tropospheric ozone have been reported recently... more ... Greenfelt, 1994). Large positive trends in the tropospheric ozone have been reported recently in a number of studies (Staehelin & Schmid, 1991; Johnson & Isaksen, 1993; Kley et al, 1994; Oltmans & Levy, 1994). For instance ...
A statistical inversion method is first presented in support to the application of kernel-based B... more A statistical inversion method is first presented in support to the application of kernel-based BRDF (bi-directional reflectance distribution function) models for the calculation of the surface albedo. We present an operational procedure for the inversion of a kernel-driven BRDF model and further albedo retrieval to be applicable to the SEVIRI/MSG reflectance measurements. The processing steps applied to space-borne POLDER sensor data were as follows: (1) quality control, (2) accumulation of a priori information on model coefficients of directional hemispherical reflectance, (3) implementation of the BRDF model inversion methods based on the biased estimation instead of usual non-biased least solution, which has too big a variance in this case. The data control procedure consists both in filtering inputs of reflectance data and output of model coefficients based on analysis criteria determined by Fisher statistics. A multi-criteria procedure follows considering in particular the shape of the reflectance angular signature: (1) T-statistics, (2) the bowl shape index, (3) the dome shape index, (4) the white sky albedo (bi-hemispherical reflectance), (5) the black sky albedo variance (directional hemispherical reflectance). The procedure is applied to POLDER data corresponding to the 16 classes of IGBP land cover classification. The statistical results include mean values and covariance matrix for the spectral BRDF model coefficients.
An alternative approach to the conventional dynamic and photochemical models is presented to fore... more An alternative approach to the conventional dynamic and photochemical models is presented to forecast urban air pollutants operationally. It is well known that there are some practical difficulties, which prevent the necessary progress in the development of these models as a forecasting tool. A fuzzy logic based method has been developed here to study the impact of meteorological factors on the evolution of air pollutant levels and to describe them quantitatively. This method meets all requirements but needs substantial amount of observational data. The developed model is based on simulation of diurnal cycles of principal meteorological variables (wind speed and direction, solar irradiance and air temperature) and the corresponding diurnal patterns of various air pollutants (O3, NO2, NO, NOy). In addition, the spatial patterns of these parameters are also studied. Both temporal and spatial parameter distributions have been considered in order to investigate impacts of meteorological factors and they are incorporated into the models as state vectors in the multidimensional space. Here we suggest that most of the weather and air pollution phenomena could be simulated by sequences of its conservation inside some fuzzy sets and the transition from one fuzzy set to another. Therefore, the important key point here is the development of the transition rules.
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