Human impacts on coastal stability in the Pechora Sea

The geoecological situation in the regions of intense industrial exploitation on the Pechora Sea coast, particularly in the Varandei area, is dangerous. Human factors intensify eolian and slope processes and thermoerosion. Coastal stability decreases and coastal retreat rates are twice as high as in regions unaffected by human activity. Industrial exploitation results in the destruction of natural environments and considerable material losses. Several housing estates and industrial constructions have already been destroyed because of coastal erosion. Damage increases each year as the cliff retreats towards the center of the Varandei settlement. The oil terminal, airport and other industrial objects are also endangered

BARENTS SEA COASTS

Barents Sea is an area of great geopolitical and economical importance, as well as an indicator of sustainable development of the Russian Federation in Arctic region. The article presents generalization made for the Barents Sea coastline. For each area a brief description of distinct geomorphologic features and coastal dynamics is outlined. The environmental forcing factors and conditions, which determine the development and present coastal dynamics at Barents Sea, are examined

Evolution of the barrier beaches in the Pechora Sea

The article discusses the main results of the complex investigations of barrier beaches in the Pechora Sea including coastal dynamics and accompanying exogenous processes (eolian transportation), lithological and micropaleontological studies of the sediment sequence and radiocarbon dating. We were the first to reconstruct sedimentation conditions and evolution of these big accumulative forms in the Pechora Sea. Stationary observations on coastal dynamics and the rate of eolian sedimentation allowed estimating the rate of barrier retreat. The mechanism of formation and evolution of dune belts on these barriers is described. Composition of diatom associations and lithological data provide evidence for facial-genetic conditions of sedimentation during accumulation of barriers. Radiocarbon datings corroborate the "young" age of the modern avandune ridges of the barrier beaches

A pan-Arctic initiative on the spatial and temporal dynamics of Arctic coasts

Permafrost coasts make up roughly one third of all coasts worldwide. Their erosion leads to the release of previously locked organic carbon, changes in ecosystems and the destruction of cultural heritage, infrastructure and whole communities. Since rapid environmental changes lead to an intensification of Arctic coastal dynamics, it is of great importance to adequately quantify current and future coastal changes. However, the remoteness of the Arctic and scarcity of data limit our understanding of coastal dynamics at a pan-Arctic scale and prohibit us from getting a complete picture of the diversity of impacts on the human and natural environment. In a joint effort of the EU project NUNATARYUK and the NSF project PerCS-Net, we seek to close this knowledge gap by collecting and analyzing all accessible high-resolution shoreline position data for the Arctic coastline. These datasets include geographical coordinates combined with coastal positions derived from archived data, surveying data, air and space born remote sensing products, or LiDAR products. The compilation of this unique dataset will enable us to reach unprecedented data coverage and will allow us a first insight into the magnitude and trends of shoreline changes on a pan-Arctic scale with locally highly resolved temporal and spatial changes in shoreline dynamics. By comparing consistently derived shoreline change data from all over the Arctic we expect that the trajectory of coastal change in the Arctic becomes evident. A synthesis of some initial results will be presented in the 2020 Arctic Report Card on Arctic Coastal Dynamics. This initiative is an ongoing effort – new data contributions are welcome

HYDROMETEOROLOGICAL FORCING OF WESTERN RUSSIAN ARCTIC COASTAL DYNAMICS: XX-CENTURY HISTORY AND CURRENT STATE

The Arctic coasts in permafrost regions are currently quickly retreating, being extremely vulnerable to the ongoing environmental changes. While the spatial variability of their retreat rates is determined by local geomorphological and cryolithological aspects, their temporal evolution is governed mainly by hydrometeorological factors, namely, wave action coupled to thermoabrasion (thermodenudation), are active during ice- free period. We define the combined wave and thermal action as “hydrometeorological stress”, and analyze its components and evolution, confirming it by known natural and remote sensing observations of coastal retreat rates. We estimated changes in the main hydrometeorological factors in the XX and XXI centuries for several sites on the coasts of the Kara andBarentsSeasbasing on observation and ERA reanalysis data. The term of hydrometeorological forcing is intended as an increment of the hydrometeorological stress, occurring because of changes of the hydrometeorological factors. Our results show that the current thermodenudation forcing amounts 15-50% of the 1979-1988 mean level and thermoabrasion forcing is equal to 35-130%. We detected 1989 (1993) – 1997 and 2005 – 2013 as periods of extreme hydrometeorological stress, as far as both thermodenudation and thermoabrasion were in a positive phase. It was also revealed that the hydrometeorological stress of the recent 10 years was apparently unprecedentedly high at the Barents-Kara region: the previous Arctic warming of the 1930-40s caused high thermoabrasion rates due to longer ice-free period despite cold summer temperatures, while, the latest ongoing warming shows previously unseen simultaneous increase in both thermodenudation and thermoabrasion

Dynamics of Low-Lying Sandy Coast of the Gydan Peninsula, Kara Sea, Russia, Based on Multi-Temporal Remote Sensing Data

The retreat rates of Arctic coasts have increased in recent decades at many sites, and an essential part of coasts considered accumulative before have turned erosional due to global climate changes and construction in the coastal zone. In this paper, we study a 7 km long coastal section of the western Gydan Peninsula in a new construction area. Based on the interpretation of multi-temporal satellite imagery, we assessed coastal dynamics in distinct periods from 1972 to 2020. We analyzed the geological structure of the coast as well as changes in hydrometeorological parameters with time, and considering the human impact, we proposed the main drivers of spatial and temporal variations of coastal dynamics. The studied low-lying sandy accumulative marine terrace was more or less stable in the period before construction (1972–2014). However, with the area’s development, the coast dynamics changed drastically: in 2014–2017, three-quarters of the studied area experienced retreat, and the average retreat rate amounted to 5.8 m/yr, up to 28.5 m/yr near the construction sites. We relate this coastal erosion intensification to human impact combined with the growth of hydrometeorological forcing. Although coastal erosion slowed down after 2017, the retreat trend remained. In the coming years, with Arctic climate warming, erosion of the studied coast will continue

Ice-Gouging Topography of the Exposed Aral Sea Bed

Ice gouging, or scouring, i.e., ice impact on the seabed, is a well-studied phenomenon in high-latitude seas. In the mid-latitudes, it remains one of the major geomorphic processes in freezing seas and large lakes. Research efforts concerning its patterns, drivers and intensity are scarce, and include aerial and geophysical studies of ice scours in the Northern Caspian Sea. This study aims to explain the origin of the recently discovered linear landforms on the exposed former Aral Sea bottom using remotely sensed data. We suggest that they are relict ice gouges, analogous to the modern ice scours of the Northern Caspian, Kara and other seas and lakes, previously studied by side scan sonar (SSS) surveys. Their average dimensions, from 3 to 90 m in width and from hundreds to thousands of meters in length, and spatial distribution were derived from satellite imagery interpretation and structure from motion-processing of UAV (unmanned aerial vehicle) images. Ice scouring features are virtually omnipresent at certain seabed sections, evidencing high ice gouging intensity in mid-latitude climates. Their greatest density is observed in the central part of the former East Aral Sea. The majority of contemporary ice gouges appeared during the rapid Aral Sea level fall between 1980 and the mid-1990s. Since then, the lake has almost completely drained, providing a unique opportunity for direct studies of exposed ice gouges using both in situ and remote-sensing techniques. These data could add to our current understanding of the scales and drivers of ice impact on the bottom of shallow seas and lakes

Dynamics of Permafrost Coasts of Baydaratskaya Bay (Kara Sea) Based on Multi-Temporal Remote Sensing Data

Arctic coasts composed of frozen deposits are extremely sensitive to climate change and human impact. They retreat with average rates of 1–2 m per year, depending on climatic and permafrost conditions. In recent decades, retreat rates have shown a tendency to increase. In this paper, we studied the coastal dynamics of two key sites (Ural and Yamal coasts) of Baydaratskaya Bay, Kara Sea, where a gas pipeline had been constructed. Based on multi-temporal aerial and satellite imagery, we identified coastal erosion rates at several time lapses, in natural conditions and under human impact, and discussed their temporal variability. In addition to planimetric (m/yr), we calculated volumetric (m3/m/yr) retreat rates of erosional coasts using ArcticDEM. We also estimated the influence of geomorphology, lithology, and permafrost structure of the coasts on spatial variations of their dynamics. Erosional coasts of the Ural key site retreat with higher mean rates (1.2 m/yr and 8.7 m3/m/yr) as compared to the Yamal key site (0.3 m/yr and 3.7 m3/m/yr) due to their exposure to higher open sea waves, more complex lithology, higher ice content and lower coastal bluffs. Since the 1960s, coastal retreat rates have been growing on both coasts of Baydaratskaya Bay; we relate this effect with Arctic climate warming. From the 1960s to 2005, such growth was moderate, while in 2005–2016 it became rapid, which may be explained by the enhanced wave and thermal action or by the onset of industrial development. The adjacent coastal segments, originally accumulative, remained relatively stable from the 1960s to 2005. After 2005, a considerable part of them began to retreat as a result of changing weather conditions and/or increasing human impact

Ice Features Of The Northern Caspian Under Sea Level Fluctuations And Ice Coverage Variations

The  Caspian Seaseasonal ice cover develops  each  winter despite  of it being  in mid-latitudes.  Increasing development of oil and gas fields challenges researchers to ensure operational safety. TheCaspian Seahas seen significant water level fluctuations in its recent history. And in the same time, it is vulnerable to effects of climate change. Extensive studies on ice conditions conducted  in the region don’t provide insights on influence of these factors in combination to describe ice cover behavior and ice features distribution.  We classify winter seasons of theNorthern Caspianby their severity calculating the cumulative freezing-degree days (CFDD). Ice charts based on aerial reconnaissance with support of the OSI-450 reanalysis provided data on the ice coverage, the timing of ice formation and destruction, the duration of the ice seasons from 1979 to 2015. We analyzed the stamukhi distribution on theNorthern Caspianfrom aerial reconnaissance for 1973–1980 and satellite imagery deciphering for 2013–2019  periods along with sea level dynamics. We found out that the amount of severe and moderate winters reduces while mild winters number increases. This leads to a decrease in the mean ice area and ice duration at theNorthern Caspian. Comparison of two periods with different sea levels and ice coverage showed that both factors affect the distribution of stamukhi by depth and distance to coast in theNorthern Caspian. Comparison of stamukhi locations in moderate winter seasons showed that their distribution is determined by the area of ice cover. In case of similar ice conditions, the stamukhi distribution is determined by sea level. The zone of their highest concentration shifts along with the coastline offset

The ACD Classification of Arctic Coasts

An important outcome of Arctic Coastal Dynamics I was the segmentation and characterization of the entire circum-Arctic coastline by regional experts which is presented in this dataset. This dataset contains data on coastal morphology, composition, dominant processes, ground ice, and environmental forcing parameters such as wind speed, storm counts, melt season, and wave energy. A listing of the variables included in the coastal classification can be found in Appendix A of the ACD II Science and Implementation Plan (2006). This information is available for over 800 segments, covering the coastline of all eight regional seas of the Arctic Ocean. The length of individual segments is variable (median length is 38 km), and depends on classification parameters and data availability. The segmentation format is scalable, allowing the adoption of future digital coastlines and the integration of additional data at higher spatial resolution. An assessment of the data quality for the more important quantitative variables has just been completed and the data will be publicly released on an internet map server (IMS). The goal of the IMS will be to allow individual users to prepare their own maps displaying the region and variables of interest. The ACD Classification was conceived as a broad enough framework to encompass existing classification schemes while capturing fundamental information for the assessment of climate change impacts and coastal processes. The implementation of the classification was done by so-called "regional experts", who, based on digital and paper products and personal knowledge provided information which was subsequently gathered into a circum-Arctic coastal database. The classification was primarily geomorphological in nature and considered: (1) the shape or form of the subaerial part of the coastal tract, (2) the marine processes acting upon the coast, (3) the shape or the form of the subaqueous part of the coastal tract and (4) the lithofacies of the materials constituting the coastal zone The beta version of the classification is made of 1331 segments each characterized by a series of geomorphological quantitative and qualitative variables. The classification is stored as an ISO 19115-compliant personal geodatabase and is therefore mappable in off-the-shelf Geographical Information Systems (GIS