D. Khoruzhii - Academia.edu (original) (raw)
Papers by D. Khoruzhii
Variability of the CO2 Flux on the Water-Atmosphere Interface in the Black Sea Coastal Waters on Various Time Scales in 2010–2014, 2018
Due to the present tendency to the increased carbon dioxide content in the atmosphere, one of the... more Due to the present tendency to the increased carbon dioxide content in the atmosphere, one of the priorities in hydrochemical research consists in studying the gas exchange in the water-atmosphere system. At that, quantity assessment of the marine areas' role in the CO2 transport requires taking into account water spatial heterogeneity based on its ability to invade or evacuate carbon dioxide. Represented are the results of estimating intensity and direction of the CO2 flux between the sea and the atmosphere in the Black Sea coastal waters in 2010-2014 executed based on the in situ hydrochemical studies and reanalysis of meteorological data. The results of direct measurements of the CO2 equilibrium partial pressure in the water surface layer and in the atmosphere near-surface layer were used for the first time for calculating the CO2 flux in the Black Sea waters. The results of analysis of the CO2 flux variability on different time scales are represented. The performed calculations show that the CO2 evacuation prevails in a warm season, whereas its invasion-in a cold season. During the off-season transitions, the water area state is close to equilibrium. The timing limits of the seasons are not constant and vary practically each year. Probable reasons of a CO2 flux seasonal variability are considered. Possible role of the abiogenic, biogenic and anthropogenic factors is assessed as a cause of the observed intensity fluctuations of the CO2 exchange between the sea and the atmosphere. It is shown that on the synoptic time scale, the CO2 flux is characterized by a narrower oscillations' amplitude as compared to its seasonal and inter-annual variability. It is noted that small-scale temporal variability of the CO2 flux is more pronounced during the cold season. The features of the carbon cycle in the Black Sea coastal waters are considered. Possibility of using information on the CO2 flux intensity and direction for assessing the water area ecological state is discussed. Keywords: CO2 flux, equilibrium partial CO2 pressure, CO2 evaporation, CO2 invasion, seasonal variability of CO2 flux, CO2 flux daily variation, inter-daily variations of CO2 flux, coastal waters, upwelling. Acknowledgments: the author is grateful to the scientist of the Oceanography Department A.V. Garmashov, the leading research engineer of the Shelf Hydrophysics Department S.A. Shutov and the junior scientist of the Sea Biogeochemistry Department E.V. Medvedev for the provided meteorological data, determination of hydrological parameters and general alkalinity during the studies. The investigation is carried out within the framework of the section "The factors and processes determining the present state and evolution of the biogeochemical structure in the Azov-Black Sea basin under the conditions of changing climate and anthropogenic impact" of the theme № 0827-2018-0003 "Fundamental studies of the oceanologic processes conditioning the marine
Variability of Equilibrium Partial Pressure of Carbon Dioxide (pCO2) and Concentration of Dissolved Inorganic Carbon (TCO2) in the Black Sea Coastal Waters in 2010 -2014, 2016
It is shown that the highest pCO2 and TCO2 variability on a small time scale is observed during t... more It is shown that the highest pCO2 and TCO2 variability on a small time scale is observed during the seawater spring warming resulted from the upwelling impact. The diurnal variations of both values (in course of the analogous period) demonstrate no pronounced tendencies; they are characterized by significant inter-annual variability. In course of summer and autumn-winter hydrological seasons, the diurnal variation of pCO2 and TCO2 is insignificant. The minimum values of TCO2 are observed in summer and autumn-winter, whereas the maximum ones-in spring during upwelling. pCO2 value in seawater reaches its maximum in late spring and minimum-in late autumn-early winter hydrological season. During the cold season, the lower pCO2 is characteristic of seawater and the higher one-of the atmosphere. Complex character of pCO2 temporal variability testifies to heterogeneity and different intensity of the factors influencing this value in different seasons. Keywords: equilibrium partial pressure of carbon dioxide (pCO2), total dissolved inorganic carbon (TCO2), diurnal variation of pCO2 and TCO2, inter-diurnal changes of pCO2 and TCO2, seasonal variations of pCO2 and TCO2, the Black Sea coastal waters, upwelling. Sea areas are among the objects, considering within the framework of study of global carbon cycle in the terrestrial biosphere, which deserve special attention. For obtaining more accurate assessment of separated areas contribution to the transport and transformation processes of inorganic carbon compounds, we zone them basing on different criteria. This is carried out due to inhomogeneity of biochemical characteristics of the seas and oceans. Sea area structure includes relatively homogeneous zones. Within them biochemical and other water parameters change insignificantly, or their changes are defined by the known patterns which are characteristic of the considered zones only. Distinguishing of sea and ocean shelf areas is due to specificity of their biochemical characteristics. With a relatively small area (slightly more than 7 % of the entire ocean surface area), these zones significantly contribute to the process of carbon dioxide (CO2) exchange between hydrosphere and atmosphere. According to existing assessments, more than 21 % of total CO2 sink from the atmosphere to the ocean falls on shelf water areas [1, 2]. The role of coastal regions in CO2 transport is conditioned by high intensity of biochemical processes in these zones. Inhomogeneity of shelf areas (in comparison with open water area parts) is their distinctive feature. The features of hydro-chemical coastal water composition are affected by a number of factors: continental runoff, biogeochemical processes in the surf zone and anthropogenic activity. Vertical mixing of water, currents and biota impact [3] also make their contribution. Due to small volume of coastal waters (less than 1 % of the World Ocean overall volume [1]), the change of their chemical composition (including the equilibrium shift between the carbonate system components) is highly dynamic.
Поступила в редакцию 16.04.2018 г., после доработки 13.06.2018 г.
On the basis of field studies executed in May 2008, we performed the analysis of the distribution... more On the basis of field studies executed in May 2008, we performed the analysis of the distribution of silicon in waters of the Sevastopol Bay under conditions of the formation of a seasonal thermocline. We discuss differences in the distributions of silicon in the surface and bottom layers, including the zone of mixing of river and sea waters. We noticed a significant difference in values of the coefficients of correlation between the concentration of silicon and the salinity for the surface and bottom layers. For bottom layer, we obtain large values of the coefficients of correlation between the concentration of silicon and other hydrochemical characteristics which are explained by the influence of the processes of transformation of organic substance.
UDC 551. 464 (262.5) On the basis of the data of hydrochemical investigations of waters of the Se... more UDC 551. 464 (262.5) On the basis of the data of hydrochemical investigations of waters of the Sevastopol Bay, we discuss the results of the analysis of the carbonate system and the total alkalinity of seawater obtained by using two methods. By using the linear method of least squares, we compare the results of the analysis of the carbonate system according to pH values and the total alkalinity and according to pH values and dissolved inorganic carbon. It is shown that, within the investigated range of pH values, Alk, and TCO 2 , the mean relative deviations of values of the fugacity of CO 2 and the concentrations of dissolved CO 2 and CO 3 2ions computed by using different input parameters are equal to 3.0, 1.0, and 9.6%, respectively. Keywords: carbonate system of the Black Sea, total alkalinity of seawater, dissolved inorganic carbon of seawater, pH value of seawater, comparison of the methods used for the analysis of the carbonate system, measurements of inorganic carbon dissolved in seawater.
Морской гидрофизический журнал, 2011
На основании гидрохимических исследований вод Севастопольской бухты обсуждаются результаты опреде... more На основании гидрохимических исследований вод Севастопольской бухты обсуждаются результаты определения карбонатной системы и общей щелочности морской воды двумя методами. С использованием линейного метода наименьших квадратов сравниваются результаты расчета карбонатной системы по pH и общей щелочности и по pH и растворенному неорганическому углероду. Показано, что в исследованном диапазоне значений pH, Alk и TCO2 средние относительные ...
Морской гидрофизический журнал, 2010
На основании натурных исследований, проведенных в мае 2008 г., выполнен анализ распределения крем... more На основании натурных исследований, проведенных в мае 2008 г., выполнен анализ распределения кремния в водах Севастопольской бухты в условиях формирования сезонного термоклина. Обсуждаются отличия в распределении кремния в поверхностном и придонном слоях, в том числе в зоне смешения речных и морских вод. Отмечено существенное различие в величинах коэффициента корреляции между концентрацией кремния и соленостью для поверхностного и придонного слоев. Для ...
It is shown that the highest pCO2 and TCO2 variability on a small time scale is observed during t... more It is shown that the highest pCO2 and TCO2 variability on a small time scale is observed during the seawater spring warming resulted from the upwelling impact. The diurnal variations of both values (in course of the analogous period) demonstrate no pronounced tendencies; they are characterized by significant inter-annual variability. In course of summer and autumn-winter hydrological seasons, the diurnal variation of pCO2 and TCO2 is insignificant. The minimum values of TCO2 are observed in summer and autumn-winter, whereas the maximum ones – in spring during upwelling. pCO2 value in seawater reaches its maximum in late spring and minimum – in late autumn – early winter hydrological season. During the cold season, the lower pCO2 is characteristic of seawater and the higher one – of the atmosphere. Complex character of pCO2 temporal variability testifies to heterogeneity and different intensity of the factors influencing this value in different seasons. Keywords: equilibrium partial pressure of carbon dioxide (pCO2), total dissolved inorganic carbon (TCO2), diurnal variation of pCO2 and TCO2, inter-diurnal changes of pCO2 and TCO2, seasonal variations of pCO2 and TCO2, the Black Sea coastal waters, upwelling. Sea areas are among the objects, considering within the framework of study of global carbon cycle in the terrestrial biosphere, which deserve special attention. For obtaining more accurate assessment of separated areas contribution to the transport and transformation processes of inorganic carbon compounds, we zone them basing on different criteria. This is carried out due to inhomogeneity of biochemical characteristics of the seas and oceans. Sea area structure includes relatively homogeneous zones. Within them biochemical and other water parameters change insignificantly, or their changes are defined by the known patterns which are characteristic of the considered zones only. Distinguishing of sea and ocean shelf areas is due to specificity of their biochemical characteristics. With a relatively small area (slightly more than 7 % of the entire ocean surface area), these zones significantly contribute to the process of carbon dioxide (CO2) exchange between hydrosphere and atmosphere. According to existing assessments, more than 21 % of total CO2 sink from the atmosphere to the ocean falls on shelf water areas [1, 2]. The role of coastal regions in CO2 transport is conditioned by high intensity of biochemical processes in these zones. Inhomogeneity of shelf areas (in comparison with open water area parts) is their distinctive feature. The features of hydro-chemical coastal water composition are affected by a number of factors: continental runoff, biogeochemical processes in the surf zone and anthropogenic activity. Vertical mixing of water, currents and biota impact [3] also make their contribution. Due to small volume of coastal waters (less than 1 % of the World Ocean overall volume [1]), the change of their chemical composition (including the equilibrium shift between the carbonate system components) is highly dynamic.
Variability of the CO2 Flux on the Water-Atmosphere Interface in the Black Sea Coastal Waters on Various Time Scales in 2010–2014, 2018
Due to the present tendency to the increased carbon dioxide content in the atmosphere, one of the... more Due to the present tendency to the increased carbon dioxide content in the atmosphere, one of the priorities in hydrochemical research consists in studying the gas exchange in the water-atmosphere system. At that, quantity assessment of the marine areas' role in the CO2 transport requires taking into account water spatial heterogeneity based on its ability to invade or evacuate carbon dioxide. Represented are the results of estimating intensity and direction of the CO2 flux between the sea and the atmosphere in the Black Sea coastal waters in 2010-2014 executed based on the in situ hydrochemical studies and reanalysis of meteorological data. The results of direct measurements of the CO2 equilibrium partial pressure in the water surface layer and in the atmosphere near-surface layer were used for the first time for calculating the CO2 flux in the Black Sea waters. The results of analysis of the CO2 flux variability on different time scales are represented. The performed calculations show that the CO2 evacuation prevails in a warm season, whereas its invasion-in a cold season. During the off-season transitions, the water area state is close to equilibrium. The timing limits of the seasons are not constant and vary practically each year. Probable reasons of a CO2 flux seasonal variability are considered. Possible role of the abiogenic, biogenic and anthropogenic factors is assessed as a cause of the observed intensity fluctuations of the CO2 exchange between the sea and the atmosphere. It is shown that on the synoptic time scale, the CO2 flux is characterized by a narrower oscillations' amplitude as compared to its seasonal and inter-annual variability. It is noted that small-scale temporal variability of the CO2 flux is more pronounced during the cold season. The features of the carbon cycle in the Black Sea coastal waters are considered. Possibility of using information on the CO2 flux intensity and direction for assessing the water area ecological state is discussed. Keywords: CO2 flux, equilibrium partial CO2 pressure, CO2 evaporation, CO2 invasion, seasonal variability of CO2 flux, CO2 flux daily variation, inter-daily variations of CO2 flux, coastal waters, upwelling. Acknowledgments: the author is grateful to the scientist of the Oceanography Department A.V. Garmashov, the leading research engineer of the Shelf Hydrophysics Department S.A. Shutov and the junior scientist of the Sea Biogeochemistry Department E.V. Medvedev for the provided meteorological data, determination of hydrological parameters and general alkalinity during the studies. The investigation is carried out within the framework of the section "The factors and processes determining the present state and evolution of the biogeochemical structure in the Azov-Black Sea basin under the conditions of changing climate and anthropogenic impact" of the theme № 0827-2018-0003 "Fundamental studies of the oceanologic processes conditioning the marine
Variability of Equilibrium Partial Pressure of Carbon Dioxide (pCO2) and Concentration of Dissolved Inorganic Carbon (TCO2) in the Black Sea Coastal Waters in 2010 -2014, 2016
It is shown that the highest pCO2 and TCO2 variability on a small time scale is observed during t... more It is shown that the highest pCO2 and TCO2 variability on a small time scale is observed during the seawater spring warming resulted from the upwelling impact. The diurnal variations of both values (in course of the analogous period) demonstrate no pronounced tendencies; they are characterized by significant inter-annual variability. In course of summer and autumn-winter hydrological seasons, the diurnal variation of pCO2 and TCO2 is insignificant. The minimum values of TCO2 are observed in summer and autumn-winter, whereas the maximum ones-in spring during upwelling. pCO2 value in seawater reaches its maximum in late spring and minimum-in late autumn-early winter hydrological season. During the cold season, the lower pCO2 is characteristic of seawater and the higher one-of the atmosphere. Complex character of pCO2 temporal variability testifies to heterogeneity and different intensity of the factors influencing this value in different seasons. Keywords: equilibrium partial pressure of carbon dioxide (pCO2), total dissolved inorganic carbon (TCO2), diurnal variation of pCO2 and TCO2, inter-diurnal changes of pCO2 and TCO2, seasonal variations of pCO2 and TCO2, the Black Sea coastal waters, upwelling. Sea areas are among the objects, considering within the framework of study of global carbon cycle in the terrestrial biosphere, which deserve special attention. For obtaining more accurate assessment of separated areas contribution to the transport and transformation processes of inorganic carbon compounds, we zone them basing on different criteria. This is carried out due to inhomogeneity of biochemical characteristics of the seas and oceans. Sea area structure includes relatively homogeneous zones. Within them biochemical and other water parameters change insignificantly, or their changes are defined by the known patterns which are characteristic of the considered zones only. Distinguishing of sea and ocean shelf areas is due to specificity of their biochemical characteristics. With a relatively small area (slightly more than 7 % of the entire ocean surface area), these zones significantly contribute to the process of carbon dioxide (CO2) exchange between hydrosphere and atmosphere. According to existing assessments, more than 21 % of total CO2 sink from the atmosphere to the ocean falls on shelf water areas [1, 2]. The role of coastal regions in CO2 transport is conditioned by high intensity of biochemical processes in these zones. Inhomogeneity of shelf areas (in comparison with open water area parts) is their distinctive feature. The features of hydro-chemical coastal water composition are affected by a number of factors: continental runoff, biogeochemical processes in the surf zone and anthropogenic activity. Vertical mixing of water, currents and biota impact [3] also make their contribution. Due to small volume of coastal waters (less than 1 % of the World Ocean overall volume [1]), the change of their chemical composition (including the equilibrium shift between the carbonate system components) is highly dynamic.
Поступила в редакцию 16.04.2018 г., после доработки 13.06.2018 г.
On the basis of field studies executed in May 2008, we performed the analysis of the distribution... more On the basis of field studies executed in May 2008, we performed the analysis of the distribution of silicon in waters of the Sevastopol Bay under conditions of the formation of a seasonal thermocline. We discuss differences in the distributions of silicon in the surface and bottom layers, including the zone of mixing of river and sea waters. We noticed a significant difference in values of the coefficients of correlation between the concentration of silicon and the salinity for the surface and bottom layers. For bottom layer, we obtain large values of the coefficients of correlation between the concentration of silicon and other hydrochemical characteristics which are explained by the influence of the processes of transformation of organic substance.
UDC 551. 464 (262.5) On the basis of the data of hydrochemical investigations of waters of the Se... more UDC 551. 464 (262.5) On the basis of the data of hydrochemical investigations of waters of the Sevastopol Bay, we discuss the results of the analysis of the carbonate system and the total alkalinity of seawater obtained by using two methods. By using the linear method of least squares, we compare the results of the analysis of the carbonate system according to pH values and the total alkalinity and according to pH values and dissolved inorganic carbon. It is shown that, within the investigated range of pH values, Alk, and TCO 2 , the mean relative deviations of values of the fugacity of CO 2 and the concentrations of dissolved CO 2 and CO 3 2ions computed by using different input parameters are equal to 3.0, 1.0, and 9.6%, respectively. Keywords: carbonate system of the Black Sea, total alkalinity of seawater, dissolved inorganic carbon of seawater, pH value of seawater, comparison of the methods used for the analysis of the carbonate system, measurements of inorganic carbon dissolved in seawater.
Морской гидрофизический журнал, 2011
На основании гидрохимических исследований вод Севастопольской бухты обсуждаются результаты опреде... more На основании гидрохимических исследований вод Севастопольской бухты обсуждаются результаты определения карбонатной системы и общей щелочности морской воды двумя методами. С использованием линейного метода наименьших квадратов сравниваются результаты расчета карбонатной системы по pH и общей щелочности и по pH и растворенному неорганическому углероду. Показано, что в исследованном диапазоне значений pH, Alk и TCO2 средние относительные ...
Морской гидрофизический журнал, 2010
На основании натурных исследований, проведенных в мае 2008 г., выполнен анализ распределения крем... more На основании натурных исследований, проведенных в мае 2008 г., выполнен анализ распределения кремния в водах Севастопольской бухты в условиях формирования сезонного термоклина. Обсуждаются отличия в распределении кремния в поверхностном и придонном слоях, в том числе в зоне смешения речных и морских вод. Отмечено существенное различие в величинах коэффициента корреляции между концентрацией кремния и соленостью для поверхностного и придонного слоев. Для ...
It is shown that the highest pCO2 and TCO2 variability on a small time scale is observed during t... more It is shown that the highest pCO2 and TCO2 variability on a small time scale is observed during the seawater spring warming resulted from the upwelling impact. The diurnal variations of both values (in course of the analogous period) demonstrate no pronounced tendencies; they are characterized by significant inter-annual variability. In course of summer and autumn-winter hydrological seasons, the diurnal variation of pCO2 and TCO2 is insignificant. The minimum values of TCO2 are observed in summer and autumn-winter, whereas the maximum ones – in spring during upwelling. pCO2 value in seawater reaches its maximum in late spring and minimum – in late autumn – early winter hydrological season. During the cold season, the lower pCO2 is characteristic of seawater and the higher one – of the atmosphere. Complex character of pCO2 temporal variability testifies to heterogeneity and different intensity of the factors influencing this value in different seasons. Keywords: equilibrium partial pressure of carbon dioxide (pCO2), total dissolved inorganic carbon (TCO2), diurnal variation of pCO2 and TCO2, inter-diurnal changes of pCO2 and TCO2, seasonal variations of pCO2 and TCO2, the Black Sea coastal waters, upwelling. Sea areas are among the objects, considering within the framework of study of global carbon cycle in the terrestrial biosphere, which deserve special attention. For obtaining more accurate assessment of separated areas contribution to the transport and transformation processes of inorganic carbon compounds, we zone them basing on different criteria. This is carried out due to inhomogeneity of biochemical characteristics of the seas and oceans. Sea area structure includes relatively homogeneous zones. Within them biochemical and other water parameters change insignificantly, or their changes are defined by the known patterns which are characteristic of the considered zones only. Distinguishing of sea and ocean shelf areas is due to specificity of their biochemical characteristics. With a relatively small area (slightly more than 7 % of the entire ocean surface area), these zones significantly contribute to the process of carbon dioxide (CO2) exchange between hydrosphere and atmosphere. According to existing assessments, more than 21 % of total CO2 sink from the atmosphere to the ocean falls on shelf water areas [1, 2]. The role of coastal regions in CO2 transport is conditioned by high intensity of biochemical processes in these zones. Inhomogeneity of shelf areas (in comparison with open water area parts) is their distinctive feature. The features of hydro-chemical coastal water composition are affected by a number of factors: continental runoff, biogeochemical processes in the surf zone and anthropogenic activity. Vertical mixing of water, currents and biota impact [3] also make their contribution. Due to small volume of coastal waters (less than 1 % of the World Ocean overall volume [1]), the change of their chemical composition (including the equilibrium shift between the carbonate system components) is highly dynamic.