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Climate change and global warming in the Sahelian region cause dramatic drought and advancing of the desert. This phenomenon could affect the plant survival and community composition, but even for surviving plants, it could affect their phenology and the insect community associated with them. In a space‐for‐time approach, we studied the case of Annona senegalensis Pers. (Annonaceae), a common shrub in tropical areas, to determine the impact of climate change on its phenology and the insects associated with its flowers and fruits. We determined the phenology phases of Annona senegalensis during a 1‐year period and assessed the abundance and diversity of insects in the Sudanian and the Sudano‐Sahelian climatic zones of Burkina Faso. Temperature, rainfall and relative humidity were recorded during 12 months in two sites per zone. Leafing of Annona senegalensis lasted 10 months in the Sudanian zone, flowering and fruiting were 3 months long. In the Sudano‐Sahelian zone, leafing lasted 8 months while flowering and fruiting were 3 and 4 months long, respectively. A total of 10,040 insects belonging to 48 species were collected in the two climatic zones. Forty‐six species were found in the Sudanian zone while 25 species were recorded in the Sudano‐Sahelian one. The variations in the plant phenology and the insect community were mainly due to the variation in rainfall across both climatic zones. Our results emphasize that advancing of the desert due to climate change could not only affect the survival of plants but for resistant species it also affect their interactions with insects and the whole insect community associated. [ABSTRACT FROM AUTHOR]

Introduction: Trees from flooded forests have to adjust their xylem hydraulic structure to face the annual flooding and the climatic conditions of the atmosphere. Usually, this adjustment of anatomical tissues in the tropics is driven by drought events inducing conservative behavior and can be recorded annually in tree rings. However, how the flood pulse and the climatic conditions influence the xylem hydraulic structure in floodplain trees is unknown. Methods: To fill this gap, we explore if flooded periods and monthly climate variation affect the annual tree growth and xylem anatomy structure for the tree species Hydrochorea corymbosa (Fabaceae) from the varzea flooded forest in the Central Amazon. We developed a 41-year ring width chronology (1971-2018) and a 30-year time series of xylem anatomy parameters (1988-2018) as mean hydraulic vessel diameter (Dh), vessel frequency (VF), and parenchyma quantity (PQ). We correlated the series with monthly hydrological and climatic data. Results: The hydrological regime did not correlate with annual tree growth in that species as we previously expected but showed correlations with the xylem anatomical structure. High flood levels during the end of the flooding period induced conservative patterns of the anatomical structure, with a negative correlation with Dh (rho June = -0.40, p < 0.05) and a positive correlation with the PQ (rho September/October = 0.42, p < 0.05). These responses show that these trees are responding to flooding similar to the tree responses to drought. Regarding the climatic variation, the annual tree growth showed a negative correlation with the vapor pressure deficit (VPD), after the second half of the flooded period with the strongest correlation happening during the non- flooded period (rho December = -0.66, p < 0. 01). These conservative patterns in tree behavior also happened when the maximum temperature negatively affected the vessel diameter (rho September = -0.42, p < 0.05). Discussion: In that case, we recognized two different moments that the environment is inducing conservative patterns in the xylem structure of those trees: 1) increasing the flood levels and 2) the high evaporative demand during the non-flooded period. In this way, the intensification of the hydrological regime, as well as the strong drought conditions during the non-flooded periods, can be a risk for H. corymbosa in the Central Amazonian floodplains. [ABSTRACT FROM AUTHOR]

The challenge of evaluating deep learning-based object detection models in complex traffic scenarios, characterized by changing weather and lighting conditions, is addressed in this study. Real-world testing proves time and cost-intensive, leading to the proposal of a Video Frame Feeding (VFF) approach as a solution. The proposed Video Frame Feeding approach acts as a bridge between object detection models and simulated environments, enabling the generation of realistic scenarios. Leveraging the CarMaker (CM) tool to simulate realistic scenarios, the framework utilizes a virtual camera to capture the simulated environment and feed video frames to an object identification model. The VFF algorithm, with automated validation using simulated ground truth data, enhances detection accuracy to over 95% at 30 frames per second within 130 meters. Employing the You Only Look Once (YOLO) version 4 and the German Traffic Sign Recognition Benchmark dataset, the study assesses a traffic signboard identification model across various climatic conditions. Notably, the VFF algorithm improves accuracy by 2% to 5% in challenging scenarios like foggy days and nights. This innovative approach not only identifies object detection issues efficiently but also offers a versatile solution applicable to any object detection model, promising improved dataset quality and robustness for enhanced model performance.

The challenge of evaluating deep learning-based object detection models in complex traffic scenarios, characterized by changing weather and lighting conditions, is addressed in this study. Real-world testing proves time and cost-intensive, leading to the proposal of a Video Frame Feeding (VFF) approach as a solution. The proposed Video Frame Feeding approach acts as a bridge between object detection models and simulated environments, enabling the generation of realistic scenarios. Leveraging the CarMaker (CM) tool to simulate realistic scenarios, the framework utilizes a virtual camera to capture the simulated environment and feed video frames to an object identification model. The VFF algorithm, with automated validation using simulated ground truth data, enhances detection accuracy to over 95% at 30 frames per second within 130 meters. Employing the You Only Look Once (YOLO) version 4 and the German Traffic Sign Recognition Benchmark dataset, the study assesses a traffic signboard identification model across various climatic conditions. Notably, the VFF algorithm improves accuracy by 2% to 5% in challenging scenarios like foggy days and nights. This innovative approach not only identifies object detection issues efficiently but also offers a versatile solution applicable to any object detection model, promising improved dataset quality and robustness for enhanced model performance. [ABSTRACT FROM AUTHOR]

Rivers in arid regions serve as crucial freshwater resources for local communities and play an essential role in global hydrological and biogeochemical cycles. The Aral Sea Basin (ASB) in Central Asia is characterized by an arid climate and river dynamics that are sensitive to climate change and human activities. Monitoring the spatiotemporal variations in river water extent in the ASB is essential to maintain an ecological balance and ensure water security. In this study, we extracted data regarding monthly river water bodies in the ASB from 2017 to 2022 by synthesizing monthly Sentinel-2 images. The water extents on the Sentinel images were automatically mapped using the Otsu method, and the river widths for all river channels were calculated using the RivWidth algorithm. We investigated the relationships between the river dynamics and the geomorphology, climatic change, human activities, and the annual and interannual variations in the river width in different reaches of the basin. The results show a seasonal variability in the river width, with most rivers reaching the largest width in the warm season and a few rivers in the middle and lower areas reaching the valley value in the warm season. Compared to their tributaries, the mainstem in the middle/lower regions showed less seasonal variability. According to interannual analysis, most of the rivers in the ASB significantly narrowed between 2017 and 2022, a phenomenon which is generally impacted by temperature and evapotranspiration variations. Comparisons show that our results provide improved information about the narrow river reaches and denser river networks compared to the previous global dataset, demonstrating the advantageous properties of high spatial resolution in Sentinel-2 imagery. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effects of seasons on the diversity and dynamics of insects associated with pig carrion in Gampela, Plateau Central Region, Burkina Faso, West Africa. Pig carcasses (Sus scrofa domesticus L.) were exposed in an open area to monitor their decomposition process and their colonization by insects during a warm and dry period (March–April 2015), a warm and wet period (August–September 2015) and a cool and dry period (December 2015–January 2016). Monitoring and entomological data collection occurred for 60 days for each study period. The decomposition process always included five stages (fresh, bloating, putrefaction, postputrefaction, and skeletal), which varied in duration depending on the study period. In sum, 118,761 insects belonging to 4 orders, 12 families, 17 genera, and 21 species were collected during the three study periods, with approximately 61% of the individuals collected during the warm and wet period. The dynamics of insect populations associated with the pig carcasses included two peaks at each study period. Formicidae was the most abundant insect family in each study period, but Musca domestica was the most abundant species. The listed species were found to belong to four trophic groups with a predominance of predators/carnivores followed by necrophagous insects. The orders, families, and trophic groups reported in this study were significantly more abundant during the warm and wet period. The results show prospects for the use of Calliphoridae, Muscidae, and Dermestidae in criminal investigations, depending on seasonal variations in Sudano-Sahelian areas. [ABSTRACT FROM AUTHOR]

Abstract Climate change and global warming in the Sahelian region cause dramatic drought and advancing of the desert. This phenomenon could affect the plant survival and community composition, but even for surviving plants, it could affect their phenology and the insect community associated with them. In a space‐for‐time approach, we studied the case of Annona senegalensis Pers. (Annonaceae), a common shrub in tropical areas, to determine the impact of climate change on its phenology and the insects associated with its flowers and fruits. We determined the phenology phases of Annona senegalensis during a 1‐year period and assessed the abundance and diversity of insects in the Sudanian and the Sudano‐Sahelian climatic zones of Burkina Faso. Temperature, rainfall and relative humidity were recorded during 12 months in two sites per zone. Leafing of Annona senegalensis lasted 10 months in the Sudanian zone, flowering and fruiting were 3 months long. In the Sudano‐Sahelian zone, leafing lasted 8 months while flowering and fruiting were 3 and 4 months long, respectively. A total of 10,040 insects belonging to 48 species were collected in the two climatic zones. Forty‐six species were found in the Sudanian zone while 25 species were recorded in the Sudano‐Sahelian one. The variations in the plant phenology and the insect community were mainly due to the variation in rainfall across both climatic zones. Our results emphasize that advancing of the desert due to climate change could not only affect the survival of plants but for resistant species it also affect their interactions with insects and the whole insect community associated.

IntroductionTrees from flooded forests have to adjust their xylem hydraulic structure to face the annual flooding and the climatic conditions of the atmosphere. Usually, this adjustment of anatomical tissues in the tropics is driven by drought events inducing conservative behavior and can be recorded annually in tree rings. However, how the flood pulse and the climatic conditions influence the xylem hydraulic structure in floodplain trees is unknown.MethodsTo fill this gap, we explore if flooded periods and monthly climate variation affect the annual tree growth and xylem anatomy structure for the tree species Hydrochorea corymbosa (Fabaceae) from the várzea flooded forest in the Central Amazon. We developed a 41-year ring width chronology (1971–2018) and a 30-year time series of xylem anatomy parameters (1988–2018) as mean hydraulic vessel diameter (Dh), vessel frequency (VF), and parenchyma quantity (PQ). We correlated the series with monthly hydrological and climatic data.ResultsThe hydrological regime did not correlate with annual tree growth in that species as we previously expected but showed correlations with the xylem anatomical structure. High flood levels during the end of the flooding period induced conservative patterns of the anatomical structure, with a negative correlation with Dh (rho June = −0.40, p < 0.05) and a positive correlation with the PQ (rho September/October = 0.42, p < 0.05). These responses show that these trees are responding to flooding similar to the tree responses to drought. Regarding the climatic variation, the annual tree growth showed a negative correlation with the vapor pressure deficit (VPD), after the second half of the flooded period with the strongest correlation happening during the non-flooded period (rho December = −0.66, p < 0. 01). These conservative patterns in tree behavior also happened when the maximum temperature negatively affected the vessel diameter (rho September = −0.42, p < 0.05).DiscussionIn that case, we recognized two different moments that the environment is inducing conservative patterns in the xylem structure of those trees: 1) increasing the flood levels and 2) the high evaporative demand during the non-flooded period. In this way, the intensification of the hydrological regime, as well as the strong drought conditions during the non-flooded periods, can be a risk for H. corymbosa in the Central Amazonian floodplains.

Climatic variations cause droughts which badly affect the environment. The study focused on monitoring droughts to aid decision-making and mitigate their negative impacts on water availability for agriculture and livelihoods in the face of increasing water demand and climate change. To assess the agricultural droughts, a new agricultural Standardized Precipitation Index (aSPI) was calculated which is not used earlier in Balochistan. Widely recommended Standardized Precipitation Index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI) were used for meteorological drought assessment. Drought indices comparison was also conducted to check the applicability. Rainfall, maximum temperature, and minimum temperature data (1992 to 2021) were utilized to calculate SPI, aSPI, and SPEI at different timescales (3, 6, 9, and 12 months) using DrinC software and SPEI calculator. Indices results revealed the following severe to extreme drought years: 1998, 1999, 2000, 2001, 2002, 2004, 2008, 2011, 2014, 2016, and 2017. It was determined that Dalbandin, Quetta, Sibi, Kalat, Khuzdar, and Zhob experienced higher extreme drought frequencies. Both long- and short-term drought durations were observed. Indices comparison showed that SPI is the most efficient drought index compared to aSPI and SPEI. This study offers valuable insights for managing water resources in the face of climate-induced droughts. HIGHLIGHTS This study reviews the literature studies on different drought indices.; Indices of aSPI, SPI, and SPEI were used for the drought assessment.; A comparison was made between the indices to select the best index.;

An experiment was conducted during eight years (2012-2019) to examine the effect of climatic variations (air temperature and precipitation) on the nutritional quality of berries of three black currant cultivars ('Ben Lomond', 'Titania' and 'Čačanska Crna'). HPLC was used for the determination of sugars and organic acids extracted from berries, while ascorbic acid and minerals were evaluated by spectrophotometry. Results indicated that the chemical profile of black currants varied among cultivars. 'Ben Lomond' and 'Čačanska Crna' exhibited excellent chemical characteristics of the berries, primarily in terms of their high sugars and organic acids content, but 'Čačanska Crna' stood out for its highest values of ascorbic acid. Also, seasonal variations caused by temperatures and precipitation affected the biosynthesis of primary metabolites in berries. The heavier precipitation and lower temperatures during berry formation and ripening promoted the accumulation of organic acids and ascorbic acid, as well as minerals P and Fe. Conversely, moderate temperatures and rainfall amounts promoted the synthesis of soluble solids, sugars and proteins, whereas higher temperatures and lower precipitation amount enhanced accumulation of the other tested minerals. PCA analysis showed the correlations among the cultivar/year interactions and identified group patterns. The results showed that the chemical properties of black currant not only depend on the genetic predisposition of the cultivar but also on climatic conditions like air temperature and precipitation, which have an important effect on nutrient metabolism in plants and promote biosynthesis and accumulation of primary metabolites in berries. [ABSTRACT FROM AUTHOR]

Rivers in arid regions serve as crucial freshwater resources for local communities and play an essential role in global hydrological and biogeochemical cycles. The Aral Sea Basin (ASB) in Central Asia is characterized by an arid climate and river dynamics that are sensitive to climate change and human activities. Monitoring the spatiotemporal variations in river water extent in the ASB is essential to maintain an ecological balance and ensure water security. In this study, we extracted data regarding monthly river water bodies in the ASB from 2017 to 2022 by synthesizing monthly Sentinel-2 images. The water extents on the Sentinel images were automatically mapped using the Otsu method, and the river widths for all river channels were calculated using the RivWidth algorithm. We investigated the relationships between the river dynamics and the geomorphology, climatic change, human activities, and the annual and interannual variations in the river width in different reaches of the basin. The results show a seasonal variability in the river width, with most rivers reaching the largest width in the warm season and a few rivers in the middle and lower areas reaching the valley value in the warm season. Compared to their tributaries, the mainstem in the middle/lower regions showed less seasonal variability. According to interannual analysis, most of the rivers in the ASB significantly narrowed between 2017 and 2022, a phenomenon which is generally impacted by temperature and evapotranspiration variations. Comparisons show that our results provide improved information about the narrow river reaches and denser river networks compared to the previous global dataset, demonstrating the advantageous properties of high spatial resolution in Sentinel-2 imagery.

Reducing vulnerability to climate change is fundamental if small-scale farming systems across the world are to address current and predicted climate change. With small-scale food production systems satisfying over half of the world's nutritional needs, ensuring their sustainability in the face of adverse climatic conditions is vital. This study examined the contribution of agroforestry systems in reducing vulnerability to climate change among small-scale farmers. The study made use of a mixed method approach consisting of household surveys, inventories, and direct field observations. Findings revealed that climatic variations have been extreme, and small-scale farmers adopt different systems of agroforestry in order to avert risks from recurrent climatic extremes. Agroforestry's ecosystem services (food, fuelwood, building materials, income generation, shade, windbreak, erosion control, soil fertility improvement, medicinal products, pollination) were frequently cited by small-scale farmers as aiding in the reduction of vulnerability to climate change. Correlation and regression coefficients revealed a strong inverse relationship (p < .01) between small-scale farmers' vulnerability to climatic changes and the practice of agroforestry, indicating that agroforestry contributes significantly in reducing vulnerability to climate change among small-scale farmers. Thus, we recommend that existing agroforestry systems should be intensified and new agroforestry technologies should be introduced in order to aid small-scale farmers reduce vulnerability to climate change. [ABSTRACT FROM AUTHOR]

The available paleosol and paleowood data from the head of the Akkol trough valley, South Chuya range, indicates a climatically driven glacier dynamic in the Russian Altai. Radiocarbon dating of paleosols and paleotree fragments help determine the beginning of the Neoglacial in this high mountain region in the middle of the Holocene. New data limit the advance of the Sofiysky glacier at that time by the front of the Historical moraine. Less so than during the Historical stage (2.3–1.7 cal kBP), glacial activity 5–4 cal kBP is also supported by rapid reforestation. The Akkem moraine in trough valleys of the Russian Altai accumulated prior to the Holocene. The limitations and difficulties of radiocarbon dating of paleosols should be considered when interpreting the dating results. [ABSTRACT FROM AUTHOR]

Effective functioning of water systems is critical to ensure the quality of human life. Therefore, failure prediction of water mains under climatic variations is necessary to avoid socio-economic and environmental losses. This paper aims to propose a hybrid model named STL-GC-LSTM for an accurate failure prediction of water mains under the impact of climatic variations. Firstly, the seasonal-trend decomposition based on Loess (STL) method is employed to decompose the failure time series. Next, significant climate variables are selected from the Granger causality (GC) test. Lastly, the final predicted failure of water mains is acquired by adding up the predictive results of the three components which are learned by Long Short-Term Memory (LSTM) models. Several evaluation metrics are used to assess the prediction performance. The results from a case study in Hong Kong imply that STL decomposition is promising for fully mining intrinsic properties of failure series. The developed hybrid models are effective in specifically identifying which component climatic variations exert influence on, and the final failure predictions show satisfactory agreement compared with peer models. This paper could provide an accurate estimation for failures of water mains ahead of time and be used as an essential complement to other numerical prediction models. [ABSTRACT FROM AUTHOR]

Investigating the spatio‐temporal patterns of desertification and its driving mechanisms is crucial for efforts to improve the ecology and environment and combat desertification. Based on meteorological and satellite remote sensing data, this paper analyzed the dynamic characteristics of desertification in the Hexi region of arid and semiarid land in Northwest China from 2000 to 2018 using a dimidiate pixel model; revealed the relationship between desertification evolution characteristics and climatic variations and anthropogenic events based on the change characteristics of net primary productivity (NPP); and then clarified the response of desertification to climatic variations and anthropogenic events using a geodetector model. Outcomes show that: (1) overall desertification in Hexi region is at a serious level, but during the study period, severe desertification decreased, mainly concentrated in the east and southwest, and non‐desertification increased, mainly near the Qilian Mountains and Shule River basin; (2) there were both spatial and temporal dynamics during the study period, with severe desertification decreasing by 11% and moderate, light, and non‐desertification increasing by 3%, 5%, and 3% respectively; (3) during 2000–2005, human activities, climate change, and their joint contribution to desertification reversal were similar, i.e., 23%, 40%, and 36%, and the former two contributed equally to desertification expansion, 38% and 41%, respectively; climate change predominated in desertification reversal in 2005–2010 and 2015–2018, while human activities predominated in desertification expansion; human activities predominated in desertification reversal and climate change predominated in desertification expansion in 2010–2015. This research can provide a theoretical basis and technical support for ecological and environmental management and sustainable socio‐economic development in arid and semiarid regions. [ABSTRACT FROM AUTHOR]

In this paper, we study a three-dimensional stochastic vegetation–water model in arid ecosystems, where the soil water and the surface water are considered. First, for the deterministic model, the possible equilibria and the related local asymptotic stability are studied. Then, for the stochastic model, by constructing some suitable stochastic Lyapunov functions, we establish sufficient conditions for the existence and uniqueness of an ergodic stationary distribution ϖ (·) . In a biological interpretation, the existence of the distribution ϖ (·) implies the long-term persistence of vegetation under certain conditions. Taking the stochasticity into account, a quasi-positive equilibrium D ¯ ∗ related to the vegetation-positive equilibrium of the deterministic model is defined. By solving the relevant Fokker–Planck equation, we obtain the approximate expression of the distribution ϖ (·) around the equilibrium D ¯ ∗ . In addition, we obtain sufficient condition R 0 E < 1 for vegetation extinction. For practical application, we further estimate the probability of vegetation extinction at a given time. Finally, based on some actual vegetation data from Wuwei in China and Sahel, some numerical simulations are provided to verify our theoretical results and study the impact of stochastic noise on vegetation dynamics. [ABSTRACT FROM AUTHOR]

Lightning electromagnetic field computation is essential in determining the impact of lightning discharge on various systems, equipment, and structures. In this regard, it is essential to know the factors affecting field propagation, and among these, the climatic conditions are essential to consider. This paper discusses the effect of different meteorological parameters on the propagation of lightning electromagnetic fields.The effect of temperature, vapor pressure, and relative humidity fluctuation on the change in the medium parameter is assessed, and the electric and magnetic field alteration is calculated. From the analysis, inconsequential variation is noted in permittivity for a temperature change from 5 ∘ C to 100 ∘ C and relative humidity from 0% to full saturation of 100%. Upon computing the variation in the field, the peak value of electric field and its time of arrival shows insignificant change. In line with this, the magnetic field propagation also remains unaffected by the weather conditions. [ABSTRACT FROM AUTHOR]

Abstract Urbanization, pollution and the modification of natural landscapes are characteristics of modern society, where the change in human relations with the environment and the impact on biodiversity are environmental determinants that affect the health-disease relationship. The skin is an organ that has a strong interface with the environment and, therefore, the prevalence patterns of dermatoses may reflect these environmental changes. In this article, aspects related to deforestation, fires, urbanization, large-scale agriculture, extensive livestock farming, pollution and climatic changes are discussed regarding their influence on the epidemiology of skin diseases. It is important that dermatologists be aware of their social responsibility in order to promote sustainable practices in their community, in addition to identifying the impacts of environmental imbalances on different dermatoses, which is essential for the prevention and treatment of these diseases.

Climatic variables not only directly affect the interannual variability (IAV) in net ecosystem exchange of CO2 (NEE) but also indirectly drive it by changing the physiological parameters. Identifying these direct and indirect paths can reveal the underlying mechanisms of carbon (C) dynamics. In this study, we applied a path analysis using flux data from 65 sites to quantify the direct and indirect climatic effects on IAV in NEE and to evaluate the potential relationships among the climatic variables and physiological parameters that represent physiology and phenology of ecosystems. We found that the maximum photosynthetic rate was the most important factor for the IAV in gross primary productivity (GPP), which was mainly induced by the variation in vapour pressure deficit. For ecosystem respiration (RE), the most important drivers were GPP and the reference respiratory rate. The biome type regulated the direct and indirect paths, with distinctive differences between forests and non-forests, evergreen needleleaf forests and deciduous broadleaf forests, and between grasslands and croplands. Different paths were also found among wet, moist and dry ecosystems. However, the climatic variables can only partly explain the IAV in physiological parameters, suggesting that the latter may also result from other biotic and disturbance factors. In addition, the climatic variables related to NEE were not necessarily the same as those related to GPP and RE, indicating the emerging difficulty encountered when studying the IAV in NEE. Overall, our results highlight the contribution of certain physiological parameters to the IAV in C fluxes and the importance of biome type and multi-year water conditions, which should receive more attention in future experimental and modelling research.

Climatic variables not only directly affect the interannual variability (IAV) in net ecosystem exchange of CO2 (NEE) but also indirectly drive it by changing the physiological parameters. Identifying these direct and indirect paths can reveal the underlying mechanisms of carbon (C) dynamics. In this study, we applied a path analysis using flux data from 65 sites to quantify the direct and indirect climatic effects on IAV in NEE and to evaluate the potential relationships among the climatic variables and physiological parameters that represent physiology and phenology of ecosystems. We found that the maximum photosynthetic rate was the most important factor for the IAV in gross primary productivity (GPP), which was mainly induced by the variation in vapour pressure deficit. For ecosystem respiration (RE), the most important drivers were GPP and the reference respiratory rate. The biome type regulated the direct and indirect paths, with distinctive differences between forests and non-forests, evergreen needleleaf forests and deciduous broadleaf forests, and between grasslands and croplands. Different paths were also found among wet, moist and dry ecosystems. However, the climatic variables can only partly explain the IAV in physiological parameters, suggesting that the latter may also result from other biotic and disturbance factors. In addition, the climatic variables related to NEE were not necessarily the same as those related to GPP and RE, indicating the emerging difficulty encountered when studying the IAV in NEE. Overall, our results highlight the contribution of certain physiological parameters to the IAV in C fluxes and the importance of biome type and multi-year water conditions, which should receive more attention in future experimental and modelling research.

The flowering phenology of plants is influenced by the unique set of environmental variations, and therefore, elucidation of important driving factors is important. The study area of Dhirkot (western Himalaya, Pakistan) is explored to record the interactions among the flowering phenology of the vascular plants and current climate along the temporal gradient from March-2015 to February-2018. A total of 38 randomly selected representative sites were visited to record the timing of flowering response and compared with mean monthly climatic data. Multivariate classification and ordination tools were used to analyze the data. The results revealed that majority (185 spp; 68%) of plant species passes through thier flowering phase in the month of July. Canonical correspondence analysis (CCA) results depicted that about 63.7% of the phenological variations were explained by the monthly explanatory climatic variables, and mean minimum temperature, precipitation, wind speed and soil moisture were significantly (p-adj. <0.05) important. Pseudo-canonical correlation of the first three CCA axes was found higher than 0.8 which depicted that the selected variables were important determinants. This study concluded that predicted future temperature increase might alter the phenological responses, and prove to be devastating for valuable plant species of this unique and very delicate western Himalayan ecosystem. [ABSTRACT FROM AUTHOR]

The relevance of the research consists in determining the age of mollusks in the Green fjord bay of West Spitsbergen Island and physical and chemical parameters of their habitant environment in conditions of the threat of destruction of geological outcrops as a result of actively developing processes of coastal thermo-abrasion and man-made load of «Arcticugol» combine. The main aim of the research is to reconstruct physical and chemical parameters of mollusks habitant environment in Holocene based on determination of mollusks species and research of isotope-geochemical composition of shells and their host rocks. Methods. Mollusk species were identified using morphological method and decomposition of shell samples – by acid dissection. Content of microelements and microelements was determined on Aurora Elite inductively coupled plasma mass spectrometer (Bruker, Germany) and on LabCenter XRF-1800 wavelength X-ray fluorescence spectrometer and stable isotope ratios – on Finningan MAT253 mass spectrometer. Age of mollusk shells was identified on liquid low-background scintillation counter. Objects of the research are quaternary sediments of the coastal cliff of Finniset cape (Green fjord bay, West Spitsbergen Island), shells of bivalve mollusks and their fragments. Results. The authors have identified the detected macrofauna complexes represented by bivalve mollusks (Hiatella arctica, Mytilus edulis, Tridonta borealis, Mya truncata) and the age of fossil shells of marine mollusks for Finniset cape, which are from 7970 to 8050 years old. It was established that the mollusks found in lower layers lived in a wormer climate than those found in the overlying layers. The authors reconstructed redox conditions using Ni/Co ratios ranging from 1,5 to 9 units and V/Cr less than 2 units. Content of the U was detected in range from 0,2 mg to 4 mg. An analysis of the Cu/Cr ratio in the outcrop shows that the distance from the area of denudation to the sedimentation area changed insignificantly. Zn concentration in sediments indicates the temporal regression of the sea and predominance of continental sedimentary regime over sea regime. Determination of Mn content in mollusk shells shown, that they lived in coastal-marine zone with high oxygen content.

Natural waters usually demonstrate the disturbance of radioactive equilibrium between parent 238U and and daughter 234U (usually, 234U/238U ≈ 0.8–3 in activities). The ratio of 234U/238U > 10 found in groundwaters can be explained by climatic variations, and it is result of 234U accumulation in permafrost rocks during cold periods and its more rapid loss compared to 238U during thawing. We tested this hypothesis for data on uranium isotope composition in water, and also chemo- and biogenic formations of the World Ocean. Most significant enrichment in 234U is discovered in the northern and internal seas during climatic warmings, which is consistent with an inferred influence of the permafrost formation and degradation on the anomalous increase of 234U/238U in groundwaters. Sampling of the Barents Sea shows that the uranium-234 enrichment in oceanic water increases with increase (a) of isolation from oceanic circulation system, (b) of the relative length of the coastal line, (c) and the contribution of continental waters to the chemical balance of the basin. [ABSTRACT FROM AUTHOR]

We conducted a dendroclimatic study in the Mustang region of the Himalayas in Nepal with aims to develop the tree-ring chronology and to check response of blue pine (Pinus wallichiana) radial growth with climate variation in the area. We extracted 120 tree cores at an altitudinal range of 2350 to 2550 m and develop a 99-year long tree-ring width chronology of blue pine which spans from 1913 to 2011.Precipitation and temperature were the main climatic factors limiting the radial growth of P. wallichiana. Winter and spring time precipitation was positively correlated to blue pine growth, specifically: precipitation during the previous November (r =0.43, p < 0.01), December (r = 0.39, p < 0.05) and current March (r = 0.34, p < 0.05). Similarly, there was a positive correlation between growth and September temperature of the current year (r = 0.398, p < 0.05), while correlation with temperature in previous year October (r = -0.446, p < 0.05) and December (r = -0.424, p < 0.05) was negative. Site conditions played a significant role in modulating the effect of precipitation and temperature on radial growth. Longer term regional scale dendrochronological studies are needed to improve our understanding on long-term climate change and its impact on forest growth. [ABSTRACT FROM AUTHOR]

In this eight-year retrospective study, we evaluated the associations between climatic variations and the biological rhythms in plasma lipids and lipoproteins in a large population of Campinas, São Paulo state, Brazil, as well as temporal changes of outcomes of cardiovascular hospitalizations. Climatic variables were obtained at the Center for Meteorological and Climatic Research Applied to Agriculture (University of Campinas - Unicamp, Brazil). The plasma lipid databases surveyed were from 27,543 individuals who had their lipid profiles assessed at the state university referral hospital in Campinas (Unicamp). The frequency of hospitalizations was obtained from the Brazilian Public Health database (DATASUS). Temporal statistical analyses were performed using the methods Cosinor or Friedman (ARIMA) and the temporal series were compared by cross-correlation functions. In normolipidemic cases (n=11,892), significantly different rhythmicity was observed in low-density lipoprotein (LDL)- and high-density lipoprotein (HDL)-cholesterol (C) both higher in winter and lower in summer. Dyslipidemia (n=15,651) increased the number and amplitude of lipid rhythms: LDL-C and HDL-C were higher in winter and lower in summer, and the opposite occurred with triglycerides. The number of hospitalizations showed maximum and minimum frequencies in winter and in summer, respectively. A coincident rhythmicity was observed of lower temperature and humidity rates with higher plasma LDL-C, and their temporal series were inversely cross-correlated. This study shows for the first time that variations of temperature, humidity, and daylight length were strongly associated with LDL-C and HDL-C seasonality, but moderately to lowly associated with rhythmicity of atherosclerotic outcomes. It also indicates unfavorable cardiovascular-related changes during wintertime.

Rice yield is vulnerable to climatic changes. High concentrations of atmospheric CO2 is noted to increase yield by improving upon nutrient uptake and water use efficiency of plants. Temperature variations also affect plant growth and eventually crop yield as it has an effect on respiration and photosynthesis. Soil fertility is an important parameter affecting the production of most crops and rice is not an exception. The cost as well as the environmental consequences of using inorganic fertilizers makes it necessary to use other soil amendments such as biochar. Field experiments are often time consuming and involves a lot of drudgery. This research was therefore conducted to model the quantities of biochar-inorganic fertilizer combinations that give optimum yields of rice and assess the effect of changes in climatic parameters on the yield of rice. CERES-Rice model was used to simulate the yield of rice using different combinations of biochar-inorganic fertilizer as soil amendments. Effects of changes in climatic parameters on the yield of rice were also simulated. The yield of rice from the simulations were sensitive to the soil amendments especially the biochar. Treatments with no biochar had relatively low rice yields compared with those with biochar. The average simulated yields were 1.5 t/ha, 5.6 t/ha and 5.5 t/ha for treatments with 0 t/ha, 20 t/ha and 30 t/ha of biochar respectively. Increasing or decreasing rainfall resulted in reduction in the yield of rice. Increasing carbon dioxide concentrations generally led to an increase in the simulated yields of rice. On the other hand, decreasing the carbon dioxide concentrations resulted in decreased simulated rice yields. It was observed that increasing temperature resulted in a reduction in rice yield for the various treatments. The reduction in the yield of rice ranged from 7.64% to 34 .67%.

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Since the late 1970s, East Asian summer monsoon (EASM) has shown a significant weakening trend, and sustained drought has occurred across North China. Placing recent climate changes in the paleoclimatic context can better understand the EASM variations. Four δ18O sequences based on tree-ring cellulose of Chinese pine were developed from Mt. Beiwudang, North China, covering a period from 1700 to 2013. Based on a climatic response analysis, a transfer function was designed to reconstruct the relative humidity from July to August (RHJA hereafter). The RHJA spans from 1765 to 2013 and explains 49% (R2adj= 48%) of the instrumental variance during the calibration period (1961–2013, r = − 0.70, p < 0.0001). The RHJA is mainly influenced by precipitation in the summer rainy season and reflect EASM variations. Spatial representation analysis indicates that RHJA represents the dry/wet variations across North China. At the interannual scale, RHJA records many extreme dry/wet events, among which the events in 1876–1878, 1900, and the 1920s are extensive droughts. Those events correspond well to ENSO events, plus further correlation and periodicity analysis indicate that RHJA contains ENSO signals. At the interdecadal scale, RHJA shows a decreasing trend and unprecedented low values from 1981 to 2013, suggesting that the weakening of EASM since the late 1970s is unprecedented in the past 249 years. Similarly, the significantly correlating region in the spatial correlation analysis, covering the Meiyu/Baiu/Changma rainfall belt and India, have also undergone a climatic shift since the late 1970s according to previous papers. [ABSTRACT FROM AUTHOR]

Agriculture is highly vulnerable to the adverse effects of climatic variations and changes (CVC). Smallholder farmers in particular bear the brunt of adverse climate variations and changes. It was within this background that this paper assessed climatic variations and changes, and the drivers of smallholder farmers’ vulnerability to adverse climatic changes in the Western Highlands of Cameroon. Secondary data (temperature and rainfall data) and primary data (obtained through a household survey of 350 smallholder farmers) were used for the study. Data analysis was done using descriptive and inferential statistical tools. It was found that, smallholder farmers perceived relatively high temperatures, intense sunshine, and erratic and scanty rainfall. Rising temperature, intense sunshine and scanty rainfall recurred annually. Recurrent extreme weather events and poverty were perceived as the major causes of vulnerability to climatic variations and changes. Most smallholder farmers (57.43%) rated their degree of vulnerability to CVC as “highly vulnerable”. A strong non-cause-effect relationship existed between vulnerability to CVC and hypothesized socio-economic, institutional and environmental explanatory variables (p

La méthode de recueil et d'identification des spores repose toujours sur l'appareil mis au point par Hirst en 1952 1, avec une identification morphologique au microscope. Les moisissures extérieures sont ubiquitaires, présentes en permanence dans l'air extérieur et leurs spores constituent la proportion la plus importante des particules aéroportées, excédant celle des grains de pollens 2, ce qui rend leur identification toujours manuelle longue et fastidieuse. Pour cette raison, les études étudiant toutes les spores extérieures sont peu nombreuses. The method of spore collection and identification is still based on the apparatus developed by Hirst in 1952 1, with morphological identification under the microscope. Outdoor moulds are ubiquitous, permanently present in the outdoor air and their spores constitute the largest proportion of airborne particles, exceeding that of pollen grains 2, which makes their identification by hand always long and tedious. For this reason, studies studying all outdoor spores are few and far between. [ABSTRACT FROM AUTHOR]

Abstract Background Seasonal changes and climatic factors like ambient temperature, sunlight duration and rainfall can influence suicidal behavior. Methods This study analyses the relationship between seasonal changes and climatic variations and suicide attempts in 2131 young patients in Istanbul, Turkey. Results In our study sample, there was an association between suicide attempts in youths and seasonal changes, as suicide attempts occurred most frequently during summer in females as well as in males. Furthermore, there was a positive correlation between the mean temperature over the past 10 days and temperature at the index day and suicide attempts in females. After seasonality effects were mathematically removed, the mean temperature 10 days before a suicide attempt remained significant in males only, indicating a possible short-term influence of temperature on suicide attempts. Conclusions This study shows an association between suicide attempts of young people and climatic changes, in particular temperature changes as well as seasonal changes. Therefore, the influence of seasonal changes and climatic factors on young suicide attempters should get more attention in research to understand the biopsychosocial mechanisms playing a role in suicide attempts of young people. As suicide attempts most frequently occur in young people, further research is of considerable clinical importance.

This article presents a fossil diatom-based, semi-quantitative reconstruction of water level fluctuations for Lake Baringo over the past 200 years as a consequence of climatic variations. A 285 cm long sediment core sample was collected using a Rod-Operated Single-drive Stationary Piston corer. Lake level was inferred using indices based on the proportion of planktonic to benthic diatom taxa (P/B ratio). The sediment archive presented distinct zones dominated by planktonic and benthic diatom flora. An initial transgression in the early 19th century was characterised as a shallow water environment dominated by planktonic Aulacoseira spp. This was a response to extreme drought during the late 18th to early 19th century. Mid-19th century was defined by a high lake stand. The late 19th to early 20th centuries experienced low water level following the widely documented aridity at the time. The mid-20th century was marked by a spectacular rise in water level that coincided with remarkably wet years during the early 1960s and late 1970s. The first decade of the 21st century witnessed widespread changes in water level. The proxy records show that lake ramping and drawdown over the years follow approximately 50-year climatic cycles. [ABSTRACT FROM AUTHOR]

Abstract An integrative multi proxy approach based on lithology, microfacies, bulk rock composition, total organic carbon (TOC), and δ13C carb was used to estimate southeastern Tethys sea level fluctuations during the deposition of the Maastrichtian-Danian oil shales in Jordan. Clay mineral assemblages were used as proxies to determine climatic variation induced sediment supply during the Cretaceous/Paleogene boundary (K/Pg) interval. The results from two cores (OS-02, Jafr Basin, southeast Jordan; OS-28 Azraq-Hamza Basin, central-east Jordan) reveal four major intervals of distinctive bulk rock composition reflecting sea level changes. Interval I (earliest Maastrichtian) with a low sea level and the formation of dolomites and a high detrital quartz input predates the oil shales. Intervals II and III in core OS-02 and interval II in core OS-28 represent the highest relative sea level following the Early Maastrichtian sea level rise on the Arabian Platform. Intervals III (core OS-02) and II (core OS-28) coincide with the highest organic matter deposition. Interval IV (core OS-02) and intervals III and IV (core OS-28) relate to the sea level regression-transgression cycle in the latest Maastrichtian through Danian and are marked by a large drop in the TOC content. Increased terrestrial influx during sea level lows is evident from two peaks/intervals of major negative δ13C carb values in core OS-28. Based on clay mineralogy it can be differentiated between warm/humid, warm/cool seasonally alternating, and cool/arid climates. When bulk rock composition is used as a sea level proxy, clay mineral assemblages from both cores reveal the dominance of warm and humid climate or, alternatively, warm/cool seasonal alternations during high sea levels (II and III core OS-02; II and IV core OS-28), while periods of arid and cool climate correspond to lower sea levels. The sea level changes and climatic variations deduced from the Jordanian oil shale successions are in agreement with the long term variations from the Egyptian Western Desert sections (southeastern Tethys), and the Tunisian El-Kef section (southweastern Tethys). Moreover, the sea level changes identified relate to the regional changes on the Arabian platform during the Maastrichtian-Danian. Highlights • 3 major sea level changes on the SE Tethys shelf in the Maastrichtian-Paleocene. • Dominance of the warm or seasonally alternating climate during high sea levels. • Dominance of similar sea level and climate conditions across the SE Tethyan shelf. • Analogy among SE and WE Tethys sea level and climatic changes in the Maastrichtian. • Negative δ13C carb excursions reflect periods of organic matter oxidation. [ABSTRACT FROM AUTHOR]

Climatic variables not only directly affect the interannual variability (IAV) in net ecosystem exchange of CO2 (NEE) but also indirectly drive it by changing the physiological parameters. Identifying these direct and indirect paths can reveal the underlying mechanisms of carbon (C) dynamics. In this study, we applied a path analysis using flux data from 65 sites to quantify the direct and indirect climatic effects on IAV in NEE and to evaluate the potential relationships among the climatic variables and physiological parameters that represent physiology and phenology of ecosystems. We found that the maximum photosynthetic rate was the most important factor for the IAV in gross primary productivity (GPP), which was mainly induced by the variation in vapour pressure deficit. For ecosystem respiration (RE), the most important drivers were GPP and the reference respiratory rate. The biome type regulated the direct and indirect paths, with distinctive differences between forests and non-forests, evergreen needleleaf forests and deciduous broadleaf forests, and between grasslands and croplands. Different paths were also found among wet, moist and dry ecosystems. However, the climatic variables can only partly explain the IAV in physiological parameters, suggesting that the latter may also result from other biotic and disturbance factors. In addition, the climatic variables related to NEE were not necessarily the same as those related to GPP and RE, indicating the emerging difficulty encountered when studying the IAV in NEE. Overall, our results highlight the contribution of certain physiological parameters to the IAV in C fluxes and the importance of biome type and multi-year water conditions, which should receive more attention in future experimental and modelling research.

One of the main sources of our knowledge about past air temperature variations is the isotopic composition of the ice cores obtained during deep drilling of the ice sheets. During 2001–2006 deep drilling was carried out at Kohnen station in Dronning Maud Land, Antarcticawithin the frameworks of the European Project for Ice Coring in Antarctica (EPICA). As a result, an ice core of 2774 mlength was obtained. Variations of air temperature are linearly dependent on isotopic composition of an ice core, but the reconstructed temperature series contains besides the climatic signal, a topographic bias. Appearance of this bias is explained by the upstream advection from the elevated sites where the ice particles were originally deposited, and by the local vertical movements of the surface of the ice sheet through time. In order to calculate this non-climatic (topographic) bias in the isotopic and reconstructed air temperature record, we applied a methodology based on mathematical ice-flow modeling. In the lower part of the ice sheet ice chronology and non-climatic biases are strongly affected by unknown value of the geothermal heat flux (G). Melt water, which was found close to the bedrock suggests that that assumed G = 54.6 mWm-2 (the average value for Antarctica) was very likely underestimated in the surroundings of Kohnen. In order to estimate the range of possible values of ice age and of non-climatic bias in the lower part of the core we carried out a series of numerical experiment with G increased by 5–30%.

Contemporary thinning of the marine-based areas of ice sheets is believed to be the consequence of the grounding line retreat caused mainly by ocean gradual warming beneath the ice shelves. In order to estimate potential contribution of ice sheets into the future sea-level rise grounding line migration must be accurately described in the mathematical models. We incorporated an algorithm based on application of the boundary condition on the mass flux across the grounding line into a two-dimensional ice flow model. In the numerical experiments, externally forced ice sheet returns to its initial equilibrium state after termination of the external forcing (either accumulation rate or sea-level change anomalies). In future, the model will be modified to incorporate buttressing effect.

The new ice core obtained from the NEEM site in the north-western Greenland (77.449˚N, 51.056˚W, 2447 m a.s.l) in 2008–2012 was expected to improve our knowledge about the Last interglacial (also known as the Eemian, ca. 115 to 130 kyr before present). A numerical modeling, the overview of which is given in this paper, aims at assistance in interpretation of the NEEM ice core. For this purpose, an area of 400 × 400 km was delineated in northwestern Greenland as the domain for the fine-scale model at 2.5 km resolution. Modeled present-day surface velocity was in good agreement with satellite and GPS measurements. The nested ice-sheet model was run over the last two glacial cycles to reconstruct the flow history relevant for interpreting the NEEM ice core. A Lagrangian backtracing procedure was applied to determine the particle trajectories of the ice drilled at the NEEM site. This provides the places of origin at the time of deposition of NEEM ice, from which the ice chronology and non-climatic biases of the records are determined. The latter biases arise from elevation changes of the ice sheet, advection of higher upstream ice, and from latitudinal contrasts in isotopical composition of the ice. These need to be separated from the isotope records to retrieve the climatic signal. In spite of initial expectations, the segment in the NEEM ice core between 2206 m and 2435 m turned out to be heavily disturbed. The presence of high isotope values below 2206 m depth however reveals that there is ice from the previous warm interglacial. Our model locates the EMBED Equation.DSMT4 maximum of the warmest Eemian ice at the right depth (2400 m). On this basis we suggest that the measured contrast between the present and the Eemian EMBED Equation.DSMT4 must be increased by about 1.5 ‰. Most of this non-climatic bias results from upstream advection over an estimated distance of ~175 km. Except for the disturbed section, we are still confident to be able to provide accurate model-based estimates of the ice chronology and non-climatic biases for the core down to ~87% of relative depth. This requires revision the palaeo-accumulation parameterization to better match thinner annual layer thicknesses observed in the ice core for the last glacial period.

Soil magnetic parameters are increasingly being linked to climatic and environmental variation, and thus provide an useful information for tracking perturbations in terrestrial environments. Climate data and the magnetic properties of modern topsoil samples were examined across a 680 km transect of the Shanxi Loess Plateau and compared to regional climate data - including temperature and precipitation. The results revealed median values of magnetic susceptibility (79.49 × 10−8 m3kg−1), saturation isothermal remanent magnetization (SIRM 1058.37 × 10−5Am2kg−1), and anhysteretic remanence magnetization (ARM 14.29 × 10−5Am2kg−1), respectively. Soils were also shown to contain a high prevalence of super paramagnetic (SP) grains, as indicated by frequency dependent susceptibility above 5%. Soil magnetic susceptibility, SIRM, and ARM showed a significant correlation with the mean annual precipitation (MAP), while a weak association was observed between ARM and mean annual temperature (MAT). The spatial distribution of topsoil magnetism in the region suggests a strong gradient from north to south, which is consistent with a moderate rainfall gradient of 350- 700 mm.yr−1. Overall, these data showed that soil magnetic properties across the Shanxi Loess Plateau are similar to other loess-derived soils in China and reflect the influence of climatic parameters in their genesis, especially rainfall. [ABSTRACT FROM AUTHOR]

Assessment of haematological parameters provides an integrated measure of fish health status. We conducted this study to evaluate the seasonal variations on the haematological parameters of an important commercial freshwater fish, Barbodes carnaticus during three major tropical seasons; pre-monsoon, monsoon and post-monsoon. Fluctuations in haematological parameters such as total erythrocyte count (TEC), total leukocyte count (TLC), haemoglobin (Hb), haematocrit (Hct), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) of B. carnaticus were assessed. Haematological parameters such as TEC and haematocrit (Hct) recorded significantly higher values (P<0.05) during monsoon. Whereas, the MCH and MCHC values were significantly (P<0.05) higher in post-monsoon. The results indicate that TEC, TLC, Hb and Hct significantly correlated (P=0.05) with water temperature and Hb significantly correlated with rainfall. The values of TLC were found high (33207 cells/mm³) during hot months of pre-monsoon, but no significant variations between seasons. The relation between seasonal variations in water temperature with haematological parameters is discussed. The baseline data generated in this study can be effectively used as a tool to monitor health status of B. carnaticus for sustainably managing the fish in tropical aquatic systems in a changing climate scenario. [ABSTRACT FROM AUTHOR]

Background: Seasonal changes and climatic factors like ambient temperature, sunlight duration and rainfall can influence suicidal behavior. Methods: This study analyses the relationship between seasonal changes and climatic variations and suicide attempts in 2131 young patients in Istanbul, Turkey. Results: In our study sample, there was an association between suicide attempts in youths and seasonal changes, as suicide attempts occurred most frequently during summer in females as well as in males. Furthermore, there was a positive correlation between the mean temperature over the past 10 days and temperature at the index day and suicide attempts in females. After seasonality effects were mathematically removed, the mean temperature 10 days before a suicide attempt remained significant in males only, indicating a possible short-term influence of temperature on suicide attempts. Conclusions: This study shows an association between suicide attempts of young people and climatic changes, in particular temperature changes as well as seasonal changes. Therefore, the influence of seasonal changes and climatic factors on young suicide attempters should get more attention in research to understand the biopsychosocial mechanisms playing a role in suicide attempts of young people. As suicide attempts most frequently occur in young people, further research is of considerable clinical importance. [ABSTRACT FROM AUTHOR]

Based on the ERA-20C, climatic variations of the boundary layer height (BLH) over arid and semiarid areas in East Asia and North Africa that span 1900-2010 were analyzed. In East Asia, the BLH exhibited a descending trend from arid region centers to the periphery. Over the past 111 years, the BLH has had a rising trend of 14.0 m decade-1. in the representative region (EA1) of the eastern areas with the 111-year average of 725 m and a decreasing trend of -1.6 m decade-1. in the representative region (EA2) of the western areas with the 111-year average of 792 m. From the mid-1960s to 1970s, EA1's BLH had a sharp rise that caused the average to increase by 93 m after the 1980s. In North Africa, the BLH exhibited a high spatial distribution in the western and southern areas and a relatively low spatial distribution in the eastern and northern areas. Over the past 111 years, the BLH has had a rising trend of 9.7 m decade-1. in the representative region (NA1) of the southwestern region with the 111-year average of 915 m and a decreasing trend of -6.3 m decade-1. in the representative region (NA2) of other regions with the 111-year average of 882 m. In the 1940s and the 1970s, NA1's BLH had two obvious increases that caused the average to increase by 51 m and 22 m, respectively, while NA2's BLH had two obvious declines that caused the average to decrease by 48 m and 7 m, respectively. On the spatial distribution, the BLH, sensible heat flux, latent heat flux, and volumetric soil water had a good corresponding relationship. On the temporal change, the BLH in East Asia had a stronger correlation with thermodynamic factors, whereas the BLH in North Africa had a stronger correlation with dynamic factors. Besides, the upper-level stratification also has some influence on the BLH's change. [ABSTRACT FROM AUTHOR]

Cold intermediate layers (CILs) constitute a key indicator of the subsurface thermal signature in many marginal and subarctic seas. Towards better understanding the impacts of natural and anthropogenic climate variability in the Black Sea, the present study elucidates processes leading to the observed changes of CIL characteristics at mesoscale and monthly-to-interannual scales by analyzing weekly temperature-salinity profiles provided by Argo floats for 2002–2015. The continuous time series data allowed to elucidate different types of CIL formation episodes. For the first time, it was possible to trace their subsequent evolution depending on the number and intensity of successive, but often intermittent, autumn-winter cooling events in addition to the ambient flow and stratification characteristics within the cyclonic interior and anticyclonic coastal eddies/gyres. The spatial distribution of CIL formation in the cold years 2003, 2006 and 2012 covered much of the Black Sea, even coastal anticyclonic eddies as a new feature which has not been documented before. The data also recorded modification of CIL during the rest of the year in terms of its thickness, position, temperature and salinity ranges in response to advective transport by the circulation system, interior turbulent mixing, and quasi-lateral intrusions associated with mesoscale features. [ABSTRACT FROM AUTHOR]

Being potentially good climatic indicators, mountain glaciers give the opportunity to analyze climatic variations which controlled their dynamic. This paper presents the results of investigations of mountain glaciers within the southeastern part of Russian Altai (SE Altai). This is one of the most northern centers of modern glaciations in Central Asia, where evidences of significantly larger Holocene mountain valley glaciers are clearly preserved in topography as well as traces of more extensive semi- ice-sheet and valley-piedmont Pleistocene glaciations. We present the radiocarbon chronology of the Holocene glaciers dynamic in the region. Applying numerical simulation, we also evaluate the influence of modern mountain valley glaciers on topography changes. Obtained values indicate the possible low estimates of more significant relief changing activity of more powerful Holocene and Pleistocene glaciers within the SE Altai. Summarizing the results of detailed geomorphological investigations and analysis of expanded radiocarbon dataset of moraines and position of the upper timber limit within the SE Altai we argue for presence of three Holocene glacial stages when glaciers were larger than modem ones. Obtained data was also correlated with the periods of soils and peats formation as well as intensifications of slope processes. The resulted chronology of glacier fluctuations refutes the traditional concept of the Russian Altai Holocene glaciations as a consecutive retreat of the late Wiinn (Sartan according to the local stratigraphic scheme) glaciers and argues their complete degradation at the head of trough valleys by the beginning of the Holocene. Moraine complexes of three Holocene glacial stages are morphologically expressed in topography of the SE Altai. They correlate with three identified periods of glacial advances in the second half of the Holocene: from 4900 to 4200 cal. years BP (Akkem stage), from 2300 to 1700 cal. years BP (Historical stage) and in the 13th - 19th centuries (Little Ice Age (LIA) or Aktru stage). Repeated forest regrowth in the presently glaciated area indicates significant retreat or even complete glacier degradation during interstage warming. Numerical simulation of the ice movement in the mountain-valley glacier and its interaction with the glacier bed allows estimating the glacial erosion rate which characterizes the contribution of glaciers to the topography denudation in mountain provinces affected by glaciations. One-dimensional numerical model of idealized glacier describes the ice flow along central flow line. Physical constants, hypsometric data and other parameters of model glacier are closely corresponded to that ones of the real SE Altai modem glaciers as well as to climatic, geological and geomorphological conditions of this region. Absolute glacier erosion rate due to numerical simulation is about 1.0· 10-3 m·a-1 with the peak value 2.0·10-3 m·a-1 near the equilibrium line. The reaction time to a stepwise change of the glacier mass balance was calculated as about 102 years. Applying this model we have also qualitatively analyzed the evolution of the glacial-valley longitudinal profile. Obtained numerical estimates were compared to available regional data which allowed outlining the range of possible values of regional glacial erosion rates. These estimates also correspond with the results obtained for other glaciated areas of Central- Asia. [ABSTRACT FROM AUTHOR]