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We analysed dinoflagellate cyst assemblages in four short sediment cores, two of them dated by radionuclides, taken in the south basin of the Caspian Sea. The interpretation of the four sequences is supported by a collection of 27 lagoonal or marine surface sediment samples. A sharp increase in the biomass of the dinocyst occurs after 1967, especially owing to Lingulodinium machaerophorum. Considering nine other cores covering parts or the whole of Holocene, this species started to develop in the Caspian Sea only during the last three millennia. By analysing instrumental data and collating existing reconstructions of sea level changes over the last few millennia, we show that the main forcing of the increase of L. machaerophorum percentages and of the recent dinocyst abundance is global climate change, especially sea surface temperature increase. Sea level fluctuations likely have a minor impact. We argue that the Caspian Sea has entered the Anthropocene. [ABSTRACT FROM AUTHOR]

At present time two main problems for Caspian Sea are: level fluctuations and its ecological condition. Historically, the transgressions and regressions of the Caspian Sea influenced the regional living and production. Based on the geological, historical and archeological data, as well as the measured data, the geological and historical variability, yearly and seasonal changes, and short-term fluctuations are studied in this paper. In addition, this paper reviews two different methodologies that explain the reasons for the level fluctuations of the Caspian Sea. The results indicate that the Caspian Sea level changes should be considered as a multistage process, which is affected by geological factors, hydro-climatic factors and water balance, as well as anthropogenic factors, and the hydro-climatic changes are the dominant influence on the Caspian Sea level. [ABSTRACT FROM AUTHOR]

The results of wind wave hindcast for the Caspian Sea for the period of 1979-2017 are presented. The WAVEWATCHIII wave model and wind forcing from the NCEP/CFSR reanalysis are used. The modeling is performed on the unstructured grid with the spacing to 1 km in the coastal zone. Mean and extreme values of wave height, length, and period are provided. It is shown that the maximum height of waves of 3% probability of exceedance is 11.7 m. The interannual variability of wave parameters is analyzed. No unambiguous trend towards increase or decrease in the storm activity was revealed over the hindcasting period. [ABSTRACT FROM AUTHOR]

Tourism industry growth in many regions of the world, along with the positive and negative economic and social consequences, has environmental impacts leading to irreversible damage. The present study aimed to investigate the impact of the tourism industry on municipal solid waste amounts especially plastics in Nowshahr City, Northern Iran. The physical components of solid waste were determined based on a simple random sampling method. The samples were collected during a one-year study period (from spring 2015 to winter 2016). The Kolmogorov-Smirnov test was performed to determine the normality of data distribution. Also, the One-Way ANOVA and Tukey tests were implemented to investigate significant differences between the seasons. The Delphi-AHP method was used to find the main criteria of solid waste increasing or the tourism effects reducing. The result showed that plastic (15.98%) and polyethylene terephthalate (PET) bottles (11.42%) constituted the highest physical components of solid wastes in the study period. The highest amounts of PET and plastic wastes were observed in the summer, exhibiting significant difference than in the winter (p < 0.05). The results showed that amount of waste in Nowshahr is completely influenced by the number of tourists, irregular presence of tourists throughout the year and season. Also, the lack of environmental awareness in the region has led to the accumulation of significant amounts of recyclable waste such as plastic. The result indicated that the importance of knowledge about the amount of produced wastes in managing and reducing environmental effects in tourism areas. Therefore, special attention should be paid to the public education and culture regarding to the separation of wstes from the source and also recycling the solid wastes as well as the public participation in study area. [ABSTRACT FROM AUTHOR]

The Caspian Sea is the largest enclosed body of water on earth, covering approximately 4×105 km2 and sharing its coast with five countries (Iran, Azerbaijan, Kazakhstan, Russia and Turkmenistan). Because it has no outlet to the ocean the Caspian Sea level (CSL) has undergone rapid shifts in response to climatic forcings, and these have been devastating for the surrounding countries. In this paper we present the initial results of a modeling effort aimed at building a regional climate model for the Caspian Sea basin suitable to study the response of the CSL to interdecadal climate variability and anthropogenic climate change. Simulations are performed using the International Centre for Theoretical Physics (ICTP) regional climate model RegCM at a 50 km grid spacing for the period 1948–1990. During this period an abrupt shift occurred in the sea level after 1977, when the CSL rose about two meters until the early 1990s. Using a simple equation of hydrologic balance for the Caspian Sea basin to predict the CSL, we show that the model is able to reproduce the observed CSL changes at interannual to multidecadal scales. The correlation coefficient between the simulated and observed annual CSL changes is 0.91 and the model is able to reproduce the abrupt shift in CSL which occurred after 1977. Analysis of the climatologies before and after 1977 indicate that the CSL rise was mostly due to an increase in precipitation over the northern basin and a decrease in evaporation over the sea, primarily during the warm season. We plan to apply our model to the investigation of the response of the CSL to anthropogenic climate forcings. [ABSTRACT FROM AUTHOR]

Abstract: This study presents combined mineralogical, chemical, isotopic (87Sr/86Sr and U–Th disequilibria series) and palynological analyses on bulk sediments and on distinct mineral phases (carbonates and clays) from a 10-m-long core drilled in the southern Caspian Sea and containing a Late Pleistocene and Early Holocene record. The data allowed identifying 1) the main variations in sedimentation, 2) the processes causing these variations, 3) the modification of erosion vs weathering, and 4) the influence of climatic and/or Caspian Sea level changes in the region since the Late Pleistocene. The chemical and mineralogical results allowed the division of the sedimentary sequence into three main units and a transition zone. The lower unit (unit U1) primarily consists of silicate and carbonate-rich detritus. Sedimentation characteristics, including observation of detritus in secular equilibrium, are relatively constant within this unit and reflect mechanical erosion in a cold climate. Unit U1 probably corresponds to a glacial period when the vegetation cover was sparse and wind and river transport of pollen were strong. Subsequently, global increase in temperatures has greatly modified the sedimentation in the Caspian Sea south basin. Biogenic sedimentation is higher in units U2 and U3, and detrital inputs varied from unit U1. Variations in detrital input are likely to be caused by decreasing aeolian contribution and by relative changes in river volumes and origins. The study of the bulk sediments, clays and carbonates reflects an increase in chemical weathering since about 10 14C ka BP ago (base of unit U2), in line with an increase in the vegetation cover. Our results suggest an evolution of continental weathering conditions in the catchment area of the Caspian Sea, from dominantly mechanical/physical erosion during the cold period to a continuous increase in weathering since the Lateglacial period, as climate improved, which illustrates the strong relation between climate, vegetation cover and weathering processes. This paper also highlights how the U–Th disequilibrium series proxy, combined with other geochemical and palynological studies, could be a useful tool to record and constrain the modification of weathering regime in response to climatic and environmental changes at regional scale. [Copyright &y& Elsevier]

Influence of North Atlantic sea surface temperature (SST) anomalies on tropical Pacific SST anomalies is examined. Both summer and winter North Atlantic SST anomalies are negatively related to central-eastern tropical Pacific SST anomalies in the subsequent months varying from 5 to 13 months. In particular, when the North Atlantic is colder than normal in the summer, an El Niño event is likely to be initiated in the subsequent spring in the tropical Pacific. Associated with summer cold North Atlantic SST anomalies is an anomalous cyclonic circulation at low-level over the North Atlantic from subsequent October to April. Corresponded to this local response, an SST-induced heating over the North Atlantic produces a teleconnected pattern, similar to the East Atlantic/West Russia teleconnection. The pattern features two anticyclonic circulations near England and Lake Baikal, and two cyclonic circulations over the North Atlantic and near the Caspian Sea. The anticyclonic circulation near Lake Baikal enhances the continent northerlies, and strengthens the East-Asian winter monsoon. These are also associated with an off-equatorial cyclonic circulation in the western Pacific during the subsequent winter and spring, which produces equatorial westerly wind anomalies in the western Pacific. The equatorial westerly wind anomalies in the winter and spring can help initiate a Pacific El Niño event following a cold North Atlantic in the summer. [ABSTRACT FROM AUTHOR]

This article analyzes Ursula Biemann’s video essay Black Sea Files as an experiment in training the viewer to perceive large-scale, transnational networks of capital, human displacement, and ecological destruction. Reacting against the norms of Western media, Biemann constructs a regime of pity that motivates the viewer to act on the suffering of distant others by shifting the mode of presentation between the local and the global, exposing and interrogating Western space-time mediations of the Baku-Tbilisi-Ceyhan oil pipeline project, and figuring agency within the project as diffuse. These mediation techniques train the viewer to engage more deeply with the content being presented, expose transnational networks of agency and responsibility within human displacement and ecological destruction, and render visible new participatory positions within those systems that offer more potential for meaningful action and resistance. The subject of a transnational oil pipeline proves fertile ground for the interrogation of the transnational networks that impact the planet and its various ecologies, and the video essay proves a powerful tool in rendering those networks visible. [ABSTRACT FROM AUTHOR]

The main components ofthe Caspian Sea water balance and water level are assessed. Stochastic models of time series of the water balance components are proposed ustng morphometric dependences specified by creating and processing digital elevation models for the flooded areas. The sea level forecast is obtained by the method of simulation modeling based on algorithms for the generation of Markovian random sequences with non-Gaussian marginal distributions. [ABSTRACT FROM AUTHOR]

An eddy-resolving model of the thermohydrodynamics of the Caspian Sea is presented. The model reproduces the climatic (decadal) variability of the sea level. Numerical experiments were performed to reconstruct the sea circulation and the evolution of its level in the second half of the 20th century. We also investigate how variations in some natural and anthropogenic factors influencing the Caspian Sea water balance impact the long-term trends of its level. [ABSTRACT FROM AUTHOR]

ABSTRACT Climate data from the southwest coast of the Caspian Sea ( CS) were statistically analysed to find connections with large-scale atmospheric variabilities and regional impacts. The study area is characterized by a subtropical humid climate. This enclave of high precipitation is extremely important for Iranian food production and is recognized for its high biodiversity. The data sets were investigated for inconsistencies before carrying out the main investigations, and several problems have been identified. The results show three distinct climatic periods in the temperature time series since 1956: 1956 to 1975 with values near to the overall mean, 1977 to 1995 with values lower by 0.5 °C and from 1996 to 2010 with values higher by 0.5 °C. These periods can be positively correlated with rapid sea level changes of the CS. Moreover, an agreement exists between the three climatic periods and the North Atlantic Oscillation ( NAO) variability. The sea surface temperature of the southern CS is shown to be the driving force of the 2 m temperatures in the study area. While temperature changes are in accordance with NAO variability, the precipitation variations show connections with ENSO and less with NAO. The trends of precipitation during the period are diverse but display mostly a weak decrease, while the trends of temperature display a clear increase, larger than that for global mean temperatures, overlaid with inter-decadal variations. [ABSTRACT FROM AUTHOR]

Long-term variations of the Caspian Sea level occur mainly due to river runoff variations (the variations of the Volga River runoff is of primary importance here). In this case, the observed and reconstructed variations of the Caspian Sea level can serve as a standard for assessing the quality of the model runoff simulated by climate models. To solve this problem, a number of detailed maps of the Caspian Sea are prepared for the series of regression and transgression stages. These data are used for verifying the results of some numerical experiments carried out within the framework of CMIP5/PMIP3. It is demonstrated that the model data can be verified depending on how well the models simulate the present-day (instrumentally observed) variations of the decadal scale reconstructed in recent 1000 years of variations: the transition from the Derbent regression to the New Caspian transgression (the 5th phase) with the insignificant sea level drop in the late 19th century and under conditions of large regression during the period of the late Pleistocene glaciation maximum. [ABSTRACT FROM AUTHOR]

We present a validation analysis of a regional climate model coupled to a distributed one dimensional (1D) lake model for the Caspian Sea Basin. Two model grid spacings are tested, 50 and 20 km, the simulation period is 1989-2008 and the lateral boundary conditions are from the ERA-Interim reanalysis of observations. The model is validated against atmospheric as well as lake variables. The model performance in reproducing precipitation and temperature mean seasonal climatology, seasonal cycles and interannual variability is generally good, with the model results being mostly within the observational uncertainty range. The model appears to overestimate cloudiness and underestimate surface radiation, although a large observational uncertainty is found in these variables. The 1D distributed lake model (run at each grid point of the lake area) reproduces the observed lake-average sea surface temperature (SST), although differences compared to observations are found in the spatial structure of the SST, most likely as a result of the absence of 3 dimensional lake water circulations. The evolution of lake ice cover and near surface wind over the lake area is also reproduced by the model reasonably well. Improvements resulting from the increase of resolution from 50 to 20 km are most significant in the lake model. Overall the performance of the coupled regional climate-1D lake model system appears to be of sufficient quality for application to climate change scenario simulations over the Caspian Sea Basin. [ABSTRACT FROM AUTHOR]

Miankaleh coastal barrier system has about 71 km length with an average of 3 km width in southeast of Caspian Sea. Forty sandy samples, collected from 5 coastal dune zones, in Miankaleh were analyzed compositionally, texturally and chemically and 31 samples from 4 nebkha field zones were analyzed for textural and geomorphological interpretation. Samples from stoss and lee sides of coastal dunes and nebkha dune field are mainly composed of medium to fine grains of sand that are well sorted, fine skewed and leptokurtic. Modal analyses of coastal dune sands show that they comprise 61% quartz, 14.74% feldspar and 24.26% rock fragments. The chemical index of alteration (CIA) value in coastal dune samples is high because of relatively warm and humid climatic condition with high amount of feldspar and rock fragments. Sedimentary and plutonic rock fragments are more than the other lithic fragments in sand samples. Nekaroud is the main source of sediments supply and as move to the east, the amount of FeO, TiO, MgO and heavy minerals in coastal dune sands decreases. The changes of the ratios of AlO/NaO and Rb/Sr can be used to evaluate the CIA value in the study area. High Zr value is another evidence of high zircon content and recycled sedimentary rocks in the source area. From west to the east, sand moving power index (M) decreases and active coastal dunes change to dormant coastal dunes. There is no coastal dune in the eastern and southern parts of the study area. Based on concentration, stabilization, height and biological cover, nebkha dune fields are classified into 4 zones. There is a meaningful relationship between different morphometrical parameters. [ABSTRACT FROM AUTHOR]

The results are analyzed of numerical experiments obtained using a one-dimensional thermodynamic model of the sea ice developed by the authors. The computations of the level-ice (fast-ice) evolution and ice hummock consolidation layer formation in different climatic situations (anomalously cold and anomalously warm winters) are carried out within the frameworks of the proposed model for the conditions being typical of the Northern Caspian Sea. The results of model computations are compared with the data of field researches carried out by the specialists of the Arctic and Antarctic Research Institute in 2003-2008. A good correspondence is demonstrated between the model computations and expeditionary data. A conclusion is made on the prospectivity of using the model for design engineering. [ABSTRACT FROM AUTHOR]

In this article, we describe physical parameters structures and different water masses using CTD measurements in southwestern part of the Caspian Sea (CS) in adjacent to Anzali Port (AP). CTD profilings were conducted along a transect perpendicular to the coastline over 13 stations from the coast down to 720m in winter 2008. According to the results the continental shelf waters are located in surface mixed layer. Surface mixed layer extends itself down to almost 100m in outer areas of the continental shelf with a weak seasonal thermocline layer between 80 to 140 m. Freshwaters inflow of local rivers is clearly seen outside continental shelf at the surface layers. Investigating the dissolved oxygen reveals that winter convection is traceable down to 500m in the lateral waters over the shelf break. Among the deeper stations that are located in continental rise and abyssal plain, 350m seems to be threshold for penetration of seasonal changes; therefore deeper waters tend to be impermeable against seasonal variances. Despite to the small variations, stability is positive in most region of the study area and temperature plays an important role in static stability and in triggering the lateral mixing. In view of both temperature-salinity and temperature-oxygen distributions in the southwestern part of the CS, three different water masses are separable in cold phase. Snapshot observation of physical properties in the early winter 2008, to some extent revealed that a mixing was triggered at least in the lateral waters of the study area. [ABSTRACT FROM AUTHOR]

The article presents developments of the environmental policy in Tehran and in European. It includes the Conference of the Parties to the Framework Convention for the Protection of the Marine Environment of the Caspian Sea which tackles several issues including the adoption of the Strategic Convention Action Programme and the development of priority Protocols to the Tehran Convention which includes the area of conservation and rational use of the aquatic resources. Another is the agreed climate package by the European Union (EU) which aims to lower carbon emission that contributes to climate change. Also, is the developments of environmental protection in the EU.

The regularities in present-day variations in the wind speed vector are examined at 18 stations along the section from Kola Peninsula to the Caspian Sea. Data on long-term variations in the major climate-forming factors and climatic parameters are generalized. The statistically significant tendency toward a considerable decline in the wind speed with a maximum module and the most frequent wind speeds of zonal, mostly western, directions (this tendency has been revealed earlier for the eastern coast of the middle and southern Caspian Sea) was found to hold for the greater part of the European Russia. Possible causes of present-day climate changes and their manifestations at the regional level are analyzed. A possible mechanism of present-day climate changes is proposed [ABSTRACT FROM AUTHOR]