Influence of the Active Layer Thickness of Permafrost in Eastern Siberia on the River Discharge of Nutrients into the Arctic Ocean

Large rivers are important links between continents and oceans for material flows that have a global impact on marine biogeochemistry. Processes in the catchment areas of large rivers can affect the flow of solutes into the global ocean. The goal was to determine how the concentration of individual components of nutrients in the rivers of Eastern Siberia changes depending on the active layer thickness of the permafrost (ALT) and to elucidate whether the ALT is a factor that can control nutrient flux to the Arctic Ocean. The method of canonical correlation analysis was applied to the data on the concentration of nutrients in the 12 largest rivers of Eastern Siberia and the active layer thickness in their catchments. We found that the concentration of nutrients such as ammonium ion (NH4) and total phosphorus (Ptotal) in river waters is higher in catchments with a deeper active layer. The waters of the mountain rivers in the south of the region (the Chara and Vitim rivers) are the richest in nutrients. Arctic rivers such as the Indigirka and Anabar were low in nutrients. The permeability of soils also affects the discharge of nutrients into rivers with surface runoff. We conclude that in the future, in the context of global climatic changes and the projected deepening of the active layer throughout the permafrost zone of the Northern Hemisphere, an increase in the supply of nutrients to the Arctic Ocean is possible.

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The influence of climate and hydrological variables on opposite anomaly in active-layer thickness between Eurasian and North American watersheds

The Cryosphere ◽

10.5194/tc-7-631-2013 ◽

2013 ◽

Vol 7 (2) ◽

pp. 631-645 ◽

Cited By ~ 29

Author(s):

H. Park ◽

J. Walsh ◽

A. N. Fedorov ◽

A. B. Sherstiukov ◽

Y. Iijima ◽

...

Keyword(s):

Layer Thickness ◽

Active Layer ◽

North American ◽

Land Surface ◽

Snow Depth ◽

The Arctic ◽

Surface Model ◽

Active Layer Thickness ◽

Hydrological Variables ◽

Permafrost Regions

Abstract. This study not only examined the spatiotemporal variations of active-layer thickness (ALT) in permafrost regions during 1948–2006 over the terrestrial Arctic regions experiencing climate changes, but also identified the associated drivers based on observational data and a simulation conducted by a land surface model (CHANGE). The focus on the ALT extends previous studies that have emphasized ground temperatures in permafrost regions. The Ob, Yenisey, Lena, Yukon, and Mackenzie watersheds are foci of the study. Time series of ALT in Eurasian watersheds showed generally increasing trends, while the increase in ALT in North American watersheds was not significant. However, ALT in the North American watersheds has been negatively anomalous since 1990 when the Arctic air temperature entered into a warming phase. The warming temperatures were not simply expressed to increases in ALT. Since 1990 when the warming increased, the forcing of the ALT by the higher annual thawing index (ATI) in the Mackenzie and Yukon basins has been offset by the combined effects of less insulation caused by thinner snow depth and drier soil during summer. In contrast, the increasing ATI together with thicker snow depth and higher summer soil moisture in the Lena contributed to the increase in ALT. The results imply that the soil thermal and moisture regimes formed in the pre-thaw season(s) provide memory that manifests itself during the summer. The different ALT anomalies between Eurasian and North American watersheds highlight increased importance of the variability of hydrological variables.

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Active-Layer Thickness Measurements Using a Handheld Penetrometer at Boreal and Tundra Sites in Eastern Siberia

Permafrost and Periglacial Processes ◽

10.1002/ppp.1908 ◽

2016 ◽

Vol 28 (1) ◽

pp. 306-313 ◽

Cited By ~ 4

Author(s):

Yoshihiro Iijima ◽

Hotaek Park ◽

Pavel Ya. Konstantinov ◽

Grigory G. Pudov ◽

Alexander N. Fedorov

Keyword(s):

Layer Thickness ◽

Active Layer ◽

Active Layer Thickness ◽

Eastern Siberia ◽

Thickness Measurements

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Seasonal and Annual Fluxes of Nutrients and Organic Matter from Large Rivers to the Arctic Ocean and Surrounding Seas

Estuaries and Coasts ◽

10.1007/s12237-011-9386-6 ◽

2011 ◽

Vol 35 (2) ◽

pp. 369-382 ◽

Cited By ~ 325

Author(s):

Robert Max Holmes ◽

James W. McClelland ◽

Bruce J. Peterson ◽

Suzanne E. Tank ◽

Ekaterina Bulygina ◽

...

Keyword(s):

Organic Matter ◽

Arctic Ocean ◽

Large Rivers ◽

The Arctic ◽

The Arctic Ocean

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On available energy in the ocean and its application to the Barents Sea

Ocean Science Discussions ◽

10.5194/osd-4-897-2007 ◽

2007 ◽

Vol 4 (6) ◽

pp. 897-931

Author(s):

R. C. Levine ◽

D. J. Webb

Keyword(s):

Arctic Ocean ◽

Barents Sea ◽

Exact Expression ◽

The Arctic ◽

Global Ocean ◽

Boundary Current ◽

Available Energy ◽

The Barents Sea ◽

The Arctic Ocean ◽

Definition Of

Abstract. Following meteorological practice the definition of available potential energy in the ocean is conventionally defined in terms of the properties of the global ocean. However there is also a requirement for a localised definition, for example the energy released when shelf water cascades down a continental shelf in the Arctic and enters a boundary current. In this note we start from first principals to obtain an exact expression for the available energy (AE) in such a situation. We show that the available energy depends on enstrophy and gravity. We also show that it is exactly equal to the work done by the pressure gradient and by buoyancy. The results are used to investigate the distribution of AE in the Barents Sea and surrounding regions relative to the interior of the Arctic Ocean. We find that water entering the Barents Sea from the Atlantic already has a high AE, that it is increased by cooling but that much of the increase is lost overcoming turbulence during the passage through the region to the Arctic Ocean. However on entering the Arctic enough available energy remains to drive a significant current around the margin of the ocean. The core of raised available energy also acts as a tracer which can be followed along the continental slope beyond the dateline.

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The Russian Old-Settlers in the Arctic Coast of Eastern Siberia: Family Name Diversity in the Context of Their Origin

Sustainability ◽

10.3390/su131910895 ◽

2021 ◽

Vol 13 (19) ◽

pp. 10895

Author(s):

Aisen V. Solovyev ◽

Tuyara V. Borisova ◽

Aleksandra M. Cherdonova ◽

Georgii P. Romanov ◽

Fedor M. Teryutin ◽

...

Keyword(s):

Arctic Ocean ◽

The Arctic ◽

Eastern Siberia ◽

White Spots ◽

The Arctic Ocean ◽

Age Of Discovery ◽

Modern Family ◽

Colonization Period ◽

The Russian Empire ◽

Different Origins

The populations of the Arctic Ocean coast in Eastern Siberia (Russia) are represented by a multicultural conglomerate of peoples of different origins: Paleo-Asiatic (Chukchi), Uralic (Yukaghirs), Tungusic (Evenks, Evens), Turkic (Yakuts, Dolgans), and Slavic (Russian explorers), who inhabited this territory during various historical periods. However, among the modern Arctic populations there are still “white spots”, such as people of the small village of “Russkoe Ust’ye”, who still have not been thoroughly studied. The main population consists of so called Russian old-settlers—the Russkoustinians. They traditionally distinguish their lineages into three groups identified by their time of settlement. First are the “Pomors”—who according to their legends are considered as the descendants of the first European colonists of the Age of Discovery, who settled the eastern shores of the Arctic Ocean in the 16th century before the inclusion of this territory in the Russian Empire in the early 17th century. Second are the “Cossacks”—who reached the Arctic during explorations of Siberia. The last are the “Zashiversk”—who arrived after the abolition of their hometown. In order to test these hypotheses, we analyzed modern family name diversity based on information on 62 individuals from 36 questionnaires. The analysis revealed that the “Pomors” lineages were presented in five families (43.5%), the “Cossacks” in one family (6.5%), and the “Zashiversk” in 37.1% of families. This fact indicates a probability that this village was founded by Russian Pomors who arrived there by the Northern Sea Routes before the official East Siberian colonization period.

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Contrasting thermal responses of permafrost to winter warming events under different snow regimes in the subarctic

10.5194/egusphere-egu21-5788 ◽

2021 ◽

Author(s):

Didac Pascual Descarrega ◽

Margareta Johansson

Keyword(s):

Layer Thickness ◽

Active Layer ◽

Snow Depth ◽

Thermal Response ◽

Winter Precipitation ◽

The Arctic ◽

Active Layer Thickness ◽

Thermal Dynamics ◽

Winter Warming

Winter warming events (WWE) in the Swedish subarctic are abrupt and short-lasting (hours-to-days) events of positive air temperature that occur during wintertime, sometimes accompanied by rainfall (rain on snow; ROS). These events cause changes in snow properties, which affect the below-ground thermal regime that, in turn, controls a suite of ecosystem processes ranging from microbial activity to permafrost and vegetation dynamics. For instance, winter melting can cause ground warming due to the shortening of the snow cover season, or ground cooling as the reduced snow depth and the formation of refrozen layers of high thermal conductivity at the base of the snowpack facilitate the release of soil heat. Apart from these interacting processes, the overall impacts of WWE on ground temperatures may also depend on the timing of the events and the preceding snowpack characteristics. The frequency and intensity of these events in the Arctic, including the Swedish subarctic, has increased remarkably during the recent decades, and is expected to increase even further during the 21st Century. In addition, snow depth (not necessarily snow duration) is projected to increase in many parts of the Arctic, including the Swedish subarctic. In 2005, a manipulation experiment was set up on a lowland permafrost mire in the Swedish subarctic, to simulate projected future increases in winter precipitation. In this study, we analyse this 15-year record of ground temperature, active layer thickness, and meteorological variables, to evaluate the short- (days to weeks) and long-term (up to 1 year) impacts of WWE on the thermal dynamics of lowland permafrost, and provide new insights into the influence of the timing of WWE and the underlying snowpack conditions on the thermal response of permafrost. On the short-term, the thermal responses to WWE are faster and stronger in areas with a shallow snowpack (5-10 cm), although these responses are more persistent in areas with a thicker snowpack (>25 cm), especially after ROS events. On the long term, permafrost in areas with a thicker snowpack exhibit a more durable warming response to WWE that results in thicker active layers at the end of the season. On the contrary, we do not observe a correlation between WWE and end of season active layer thickness in areas with a shallow snowpack.&#160;

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A perfect bowl-like submesoscale vortex from seismic reflection transect in the Chukchi Sea, Arctic Ocean

10.5194/egusphere-egu21-4760 ◽

2021 ◽

Author(s):

Shun Yang ◽

Haibin Song ◽

Kun Zhang

Keyword(s):

Arctic Ocean ◽

Water Column ◽

Chukchi Sea ◽

The Arctic ◽

Global Ocean ◽

Physical Oceanography ◽

Depth Range ◽

Seismic Line ◽

The Arctic Ocean ◽

The Right

The eddies are ubiquitous in the ocean and play an important role in the transportation and redistribution of heat, salt, carbon, nutrients and other materials in the global ocean, thus can regulate global climate and affect the distribution of marine organism. Compared with mesoscale eddies, submesoscale vortices (SVs) have smaller spatial and temporal scales, which impose higher requirements on observation and simulation. The oceanic SVs have a strong vertical velocity, which provides an important supply of nutrients in the upper ocean.Many researchers have studied the SVs in the Arctic Ocean by physical oceanography methods (e.g., in-situ measurements and satellite observations). Here, we found a perfect bowl-like SV using a new method named seismic oceanography (SO). SO can use multichannel seismic (MCS) reflection data to produce surprisingly detailed images of water column. Compared with the traditional physical oceanography methods, SO has the advantages of high acquisition efficiency, high lateral resolution (~10 m) and full depth imaging of seawater.We used MCS data to image the water column in the in autumn Northeast Chukchi Sea, and captured a perfect bowl-like structure with a depth range of ~200-620m. The structure is almost bilaterally symmetric and has dip angles of 4.8&#176; and 5.5&#176; on the left and on the right, respectively. And it has a horizontal scale of about 12 km at the top and 4.5 km at the bottom, and both the top and bottom of it are near horizontal. The reflections are almost blank in its interior, but are intense and very narrow (~30 m thick) at the lateral boundaries. This indicated that the interior water is homogeneous and quite different from that around it. Fortunately, there is an XBT station near the seismic line and collected almost simultaneously (only one day apart) with the seismic line. The XBT station shows obvious high temperature anomaly over 2&#176;C at the depth of 210-700 m. Therefore, we concluded the structure is a subsurface warm SV, i.e. anticyclonic warm eddy, and may be a submesoscale coherent vortex (SCV). The anomalies from the surrounding water masses indicate that the SV was created at the edge of the Arctic Ocean and then advected here.In addition, we used Rossby number (Ro) and Okubo-Weiss (OW) parameter calculated from daily-averaged re-analysis hydrographic data (~3.5 km of grid spacing at 75&#176;N ) from Copernicus Marine Environment Monitoring Service (CMEMS) to analyze the SV. Result shows that the values of the Ro and OW parameter in the area of the SV are both negative. This also suggests that this SV is an anticyclone. This submesoscale anticyclonic vortex may be generated from the friction effect between the warm inflow from the North Pacific and the right wall of Barrow Canyon after passing through the Bering Strait, and then transported to the Northeast of Chukchi Sea by the Beaufort Gyre.

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Seasonal methane and carbon dioxide emissions from the coastal nearshore of the Kolyma river, Siberia.

10.5194/egusphere-egu21-9535 ◽

2021 ◽

Author(s):

Juri Palmtag ◽

Cara Manning ◽

Michael Bedington ◽

Matthias Fuchs ◽

Mathias Göckede ◽

...

Keyword(s):

Carbon Dioxide ◽

Arctic Ocean ◽

Carbon Dioxide Emissions ◽

Open Water ◽

The Arctic ◽

Global Ocean ◽

Nearshore Zone ◽

Terrestrial Organic Matter ◽

The Arctic Ocean ◽

Kolyma River

Arctic rivers deliver &#8776;11% of global river discharge into the Arctic Ocean, while this ocean represents only &#8776;1% of the global ocean volume. Ongoing climate warming across the Arctic, and specifically Siberia, has led to regional-scale changes in precipitation patterns, greater rates of permafrost thaw and active layer deepening, as well as enhanced riverbank and coastal erosion. Combined, these climatic and cryospheric perturbations have already resulted in increased freshwater discharge and changes to constituent loads (e.g. dissolved organic carbon - OC) supplied from land to the Arctic Ocean.To date, the majority of studies examining terrestrial organic matter (OM) delivery to the Arctic Ocean have focused almost entirely on freshwater (riverine) or fully-marine environments and been conducted during late summer seasons &#8211; often due to logistical constraints. Despite this, an improved understanding of how OC is transformed, mineralised and released during transit through the highly reactive nearshore estuarine environment is critical for examining the fate and influence of terrestrial OM on the Arctic Ocean. Capturing seasonality over the open water period is also necessary to identify current OM fluxes to the ocean vs the atmosphere, and aid in constraining how future changes may modify them.Here we focus upon carbon dioxide (CO2) and methane (CH4) measurements collected during six repeated transects of the Kolyma River and nearshore zone (covering ~120 km) from 2019. Transects spanned almost the entirety of the riverine open water season (June to September). We use these results, in parallel with gas concentrations derived from prior studies, to develop and validate a simple box-model of gas emissions from the nearshore zone.Observations and model&#8208;derived output data reveal that more than 50% of the cumulative gross delivery of CH4 and CO2 to the coastal ocean occurred during the freshet period with dissolved CH4 concentrations in surface water reaching 660 Nanomole per liter [nmol/l]. These results demonstrate the relevance of seasonal dynamics and its spatial variability which are needed in order to estimate greenhouse gas fluxes on an annual basis.More accurate understanding of land-ocean carbon fluxes in the Arctic is therefore crucial to mitigate the effects of climate change and to support the decisions of policy makers.

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A SPATIO-TEMPORAL FRAMEWORK FOR MODELING ACTIVE LAYER THICKNESS

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsannals-ii-4-w2-199-2015 ◽

2015 ◽

Vol II-4/W2 ◽

pp. 199-206

Author(s):

J. Touyz ◽

D. A. Streletskiy ◽

F. E. Nelson ◽

T. V. Apanasovich

Keyword(s):

Layer Thickness ◽

Active Layer ◽

Environmental Changes ◽

Predictive Accuracy ◽

The Arctic ◽

Active Layer Thickness ◽

Error Statistics ◽

Stochastic Component ◽

Spatio Temporal ◽

Naive Model

The Arctic is experiencing an unprecedented rate of environmental and climate change. The active layer (the uppermost layer of soil between the atmosphere and permafrost that freezes in winter and thaws in summer) is sensitive to both climatic and environmental changes, and plays an important role in the functioning, planning, and economic activities of Arctic human and natural ecosystems. This study develops a methodology for modeling and estimating spatial-temporal variations in active layer thickness (ALT) using data from several sites of the Circumpolar Active Layer Monitoring network, and demonstrates its use in spatial-temporal interpolation. The simplest model’s stochastic component exhibits no spatial or spatio-temporal dependency and is referred to as the naïve model, against which we evaluate the performance of the other models, which assume that the stochastic component exhibits either spatial or spatio-temporal dependency. The methods used to fit the models are then discussed, along with point forecasting. We compare the predicted fit of the various models at key study sites located in the North Slope of Alaska and demonstrate the advantages of space-time models through a series of error statistics such as mean squared error, mean absolute and percent deviance from observed data. We find the difference in performance between the spatio-temporal and remaining models is significant for all three error statistics. The best stochastic spatio-temporal model increases predictive accuracy, compared to the naïve model, of 33.3%, 36.2% and 32.5% on average across the three error metrics at the key sites for a one-year hold out period.

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Model constraints on the anthropogenic carbon budget of the Arctic Ocean

10.5194/bg-2018-283 ◽

2018 ◽

Cited By ~ 1

Author(s):

Jens Terhaar ◽

James C. Orr ◽

Marion Gehlen ◽

Christian Ethé ◽

Laurent Bopp

Keyword(s):

Ocean Acidification ◽

Arctic Ocean ◽

Ocean Circulation ◽

The Arctic ◽

Global Ocean ◽

Cmip5 Models ◽

Lateral Transport ◽

Coarse Resolution ◽

The Arctic Ocean ◽

Anthropogenic Carbon

Abstract. The Arctic Ocean is projected to experience not only amplified climate change but also amplified ocean acidification. Modeling future acidification depends on our ability to simulate baseline conditions and changes over the industrial era. Such centennial-scale changes require a global model to account for exchange between the Arctic and surrounding regions. Yet the coarse resolution of typical global models may poorly resolve that exchange as well as critical features of Arctic Ocean circulation. Here we assess how simulations of Arctic Ocean storage of anthropogenic carbon (Cant), the main driver of open- ocean acidification, differ when moving from coarse to eddy admitting resolution in a global ocean circulation-biogeochemistry model (NEMO-PISCES). The Arctic's regional storage of Cant is enhanced as model resolution increases. While the coarse- resolution model configuration ORCA2 (2°) stores 2.0 Pg C in the Arctic Ocean between 1765 and 2005, the eddy-admitting versions ORCA05 and ORCA025 (1/2° and 1/4°) store 2.4 and 2.6 Pg C. That result from ORCA025 falls within the uncertainty range from a previous data-based Cant storage estimate (2.5 to 3.3 Pg C). Yet those limits may each need to be reduced by about 10 % because data-based Cant concentrations in deep waters remain at ∼ 6 μmol kg−1, while they should be almost negligible by analogy to the near-zero observed CFC-12 concentrations from which they are calculated. Across the three resolutions, there was roughly three times as much anthropogenic carbon that entered the Arctic Ocean through lateral transport than via the flux of CO2 across the air-sea interface. Wider comparison to nine earth system models that participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5) reveals much larger diversity of stored anthropogenic carbon and lateral transport. Only the CMIP5 models with higher lateral transport obtain Cant inventories that are close to the data-based estimates. Increasing resolution also enhances acidification, e.g., with greater shoaling of the Arctic's average depth of the aragonite saturation horizon during 1960–2012, from 50 m in ORCA2 to 210 m in ORCA025. To assess the potential to further refine modeled estimates of the Arctic Ocean's Cant storage and acidification, sensitivity tests that adjust model parameters are needed given that century-scale global ocean biogeochemical simulations still cannot be run routinely at high resolution.

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