The cumulative impacts of climate change on Fraser River sockeye salmon (Oncorhynchus nerka) and implications for management

2011 ◽  
Vol 68 (4) ◽  
pp. 718-737 ◽  
Author(s):  
Michael Healey
Keyword(s):  
Climate Change ◽  
Sockeye Salmon ◽  
Pacific Salmon ◽  
Oncorhynchus Nerka ◽  
The Arctic ◽  
Fraser River ◽  
Life Stages ◽  
Cumulative Impact ◽  
Marine Habitats ◽  
The Impact

Anadromous Pacific salmon ( Oncorhynchus spp.) are vulnerable to climate change in both freshwater and marine habitats. I use a qualitative model to assess the cumulative effects of climate change across life stages and generations of Fraser River sockeye salmon ( Oncorhynchus nerka ) and other salmon species. The effects of climate change most relevant to Fraser River sockeye include warming of freshwater and marine habitats, altered hydrology in spawning rivers, reduced productivity in nursery habitats, and changed distribution and phenology of predator and prey species. The weight of evidence indicates that these changes will negatively affect growth and survival of Fraser River sockeye at all life stages. Effects on one life stage will also carry forward to heighten adverse effects at subsequent life stages and across generations so that the cumulative impact is greater than the impact on individual stages. Salmon can adapt to climate change but probably not enough to sustain productivity. In the south, focus of policy and management on conserving and enhancing resilience is needed to retain some salmon production. At the same time, Arctic habitats are becoming accessible to salmon. Management in the Arctic should protect potentially productive habitats from development and facilitate their colonization by Pacific salmon.

A MODELING SYSTEM FOR CLIMATE CHANGE RISK ASSESSMENT, MANAGEMENT AND HEDGING IN COASTAL AREAS

2017 ◽  
Author(s):  
Sergei Soldatenko ◽  
Sergei Soldatenko ◽  
Genrikh Alekseev ◽  
Genrikh Alekseev ◽  
Alexander Danilov ◽  
...  
Keyword(s):  
Climate Change ◽  
Risk Assessment ◽  
Coastal Areas ◽  
Mitigation Strategies ◽  
System Structure ◽  
The Arctic ◽  
Risk Modeling ◽  
Wide Range ◽  
Adverse Weather ◽  
The Impact

Every aspect of human operations faces a wide range of risks, some of which can cause serious consequences. By the start of 21st century, mankind has recognized a new class of risks posed by climate change. It is obvious, that the global climate is changing, and will continue to change, in ways that affect the planning and day to day operations of businesses, government agencies and other organizations and institutions. The manifestations of climate change include but not limited to rising sea levels, increasing temperature, flooding, melting polar sea ice, adverse weather events (e.g. heatwaves, drought, and storms) and a rise in related problems (e.g. health and environmental). Assessing and managing climate risks represent one of the most challenging issues of today and for the future. The purpose of the risk modeling system discussed in this paper is to provide a framework and methodology to quantify risks caused by climate change, to facilitate estimates of the impact of climate change on various spheres of human activities and to compare eventual adaptation and risk mitigation strategies. The system integrates both physical climate system and economic models together with knowledge-based subsystem, which can help support proactive risk management. System structure and its main components are considered. Special attention is paid to climate risk assessment, management and hedging in the Arctic coastal areas.

scholarly journals Thirty-Nine-Year Wave Hindcast, Storm Activity, and Probability Analysis of Storm Waves in the Kara Sea, Russia

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 648
Author(s):  
Stanislav Myslenkov ◽  
Vladimir Platonov ◽  
Alexander Kislov ◽  
Ksenia Silvestrova ◽  
Igor Medvedev
Keyword(s):  
Climate Change ◽  
Pareto Distribution ◽  
Linear Trend ◽  
Wind Waves ◽  
Kara Sea ◽  
The Arctic ◽  
Storm Events ◽  
Storm Activity ◽  
Significant Linear Trend ◽  
The Impact

The recurrence of extreme wind waves in the Kara Sea strongly influences the Arctic climate change. The period 2000–2010 is characterized by significant climate warming, a reduction of the sea ice in the Arctic. The main motivation of this research to assess the impact of climate change on storm activity over the past 39 years in the Kara Sea. The paper presents the analysis of wave climate and storm activity in the Kara Sea based on the results of numerical modeling. A wave model WAVEWATCH III is used to reconstruct wind wave fields for the period from 1979 to 2017. The maximum significant wave height (SWH) for the whole period amounts to 9.9 m. The average long-term SWH for the ice-free period does not exceed 1.3 m. A significant linear trend shows an increase in the storm wave frequency for the period from 1979 to 2017. It is shown that trends in the storm activity of the Kara Sea are primarily regulated by the ice. Analysis of the extreme storm events showed that the Pareto distribution is in the best agreement with the data. However, the extreme events with an SWH more than 6‒7 m deviate from the Pareto distribution.

Early Holocene ocean conditions off the Zachariæ Isstrøm, Northeast Greenland

2021 ◽  
Author(s):  
Joanna Davies ◽  
Anders Møller Mathiasen ◽  
Kristiane Kristensen ◽  
Christof Pearce ◽  
Marit-Solveig Seidenkrantz
Keyword(s):  
Climate Change ◽  
Ice Sheet ◽  
Greenland Ice Sheet ◽  
Atlantic Water ◽  
The Arctic ◽  
Future Climate Change ◽  
Polar Regions ◽  
Ice Shelf ◽  
Outlet Glacier ◽  
The Impact

<p>The polar regions exhibit some of the most visible signs of climate change globally; annual mass loss from the Greenland Ice Sheet (GrIS) has quadrupled in recent decades, from 51 ± 65 Gt yr<sup>−1</sup> (1992-2001) to 211 ± 37 Gt yr<sup>−1</sup> (2002-2011). This can partly be attributed to the widespread retreat and speed-up of marine-terminating glaciers. The Zachariae Isstrøm (ZI) is an outlet glacier of the Northeast Greenland Ice Steam (NEGIS), one of the largest ice streams of the GrIS (700km), draining approximately 12% of the ice sheet interior. Observations show that the ZI began accelerating in 2000, resulting in the collapse of the floating ice shelf between 2002 and 2003. By 2014, the ice shelf extended over an area of 52km<sup>2</sup>, a 95% decrease in area since 2002, where it extended over 1040km<sup>2</sup>. Paleo-reconstructions provide an opportunity to extend observational records in order to understand the oceanic and climatic processes governing the position of the grounding zone of marine terminating glaciers and the extent of floating ice shelves. Such datasets are thus necessary if we are to constrain the impact of future climate change projections on the Arctic cryosphere.</p><p>A multi-proxy approach, involving grain size, geochemical, foraminiferal and sedimentary analysis was applied to marine sediment core DA17-NG-ST8-92G, collected offshore of the ZI, on  the Northeast Greenland Shelf. The aim was to reconstruct changes in the extent of the ZI and the palaeoceanographic conditions throughout the Early to Mid Holocene (c.a. 12,500-5,000 cal. yrs. BP). Evidence from the analysis of these datasets indicates that whilst there has been no grounded ice at the site over the last 12,500 years, the ice shelf of the ZI extended as a floating ice shelf over the site between 12,500 and 9,200 cal. yrs. BP, with the grounding line further inland from our study site. This was followed by a retreat in the ice shelf extent during the Holocene Thermal Maximum; this was likely to have been governed, in part, by basal melting driven by Atlantic Water (AW) recirculated from Svalbard or from the Arctic Ocean. Evidence from benthic foraminifera suggest that there was a shift from the dominance of AW to Polar Water at around 7,500 cal. yrs. BP, although the ice shelf did not expand again despite of this cooling of subsurface waters.</p>

scholarly journals Regional variability of acidification in the Arctic: a sea of contrasts

2014 ◽  
Vol 11 (2) ◽  
pp. 293-308 ◽  
Author(s):  
E. E. Popova ◽  
A. Yool ◽  
Y. Aksenov ◽  
A. C. Coward ◽  
T. R. Anderson
Keyword(s):  
Climate Change ◽  
Primary Production ◽  
Arctic Ocean ◽  
Canadian Arctic ◽  
Atmospheric Co2 ◽  
The Arctic ◽  
Canadian Arctic Archipelago ◽  
Regional Variability ◽  
The Arctic Ocean ◽  
The Impact

Abstract. The Arctic Ocean is a region that is particularly vulnerable to the impact of ocean acidification driven by rising atmospheric CO2, with potentially negative consequences for calcifying organisms such as coccolithophorids and foraminiferans. In this study, we use an ocean-only general circulation model, with embedded biogeochemistry and a comprehensive description of the ocean carbon cycle, to study the response of pH and saturation states of calcite and aragonite to rising atmospheric pCO2 and changing climate in the Arctic Ocean. Particular attention is paid to the strong regional variability within the Arctic, and, for comparison, simulation results are contrasted with those for the global ocean. Simulations were run to year 2099 using the RCP8.5 (an Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) scenario with the highest concentrations of atmospheric CO2). The separate impacts of the direct increase in atmospheric CO2 and indirect effects via impact of climate change (changing temperature, stratification, primary production and freshwater fluxes) were examined by undertaking two simulations, one with the full system and the other in which atmospheric CO2 was prevented from increasing beyond its preindustrial level (year 1860). Results indicate that the impact of climate change, and spatial heterogeneity thereof, plays a strong role in the declines in pH and carbonate saturation (Ω) seen in the Arctic. The central Arctic, Canadian Arctic Archipelago and Baffin Bay show greatest rates of acidification and Ω decline as a result of melting sea ice. In contrast, areas affected by Atlantic inflow including the Greenland Sea and outer shelves of the Barents, Kara and Laptev seas, had minimal decreases in pH and Ω because diminishing ice cover led to greater vertical mixing and primary production. As a consequence, the projected onset of undersaturation in respect to aragonite is highly variable regionally within the Arctic, occurring during the decade of 2000–2010 in the Siberian shelves and Canadian Arctic Archipelago, but as late as the 2080s in the Barents and Norwegian seas. We conclude that, for future projections of acidification and carbonate saturation state in the Arctic, regional variability is significant and needs to be adequately resolved, with particular emphasis on reliable projections of the rates of retreat of the sea ice, which are a major source of uncertainty.

Biochemical Studies on Sockeye Salmon During Spawning Migration: XI. The Free Histidine Content of the Tissues

1960 ◽  
Vol 17 (3) ◽  
pp. 347-351 ◽  
Author(s):  
J. D. Wood ◽  
D. W. Duncan ◽  
M. Jackson
Keyword(s):  
Amino Acid ◽  
Sockeye Salmon ◽  
Alimentary Tract ◽  
Oncorhynchus Nerka ◽  
The Other ◽  
Spawning Migration ◽  
Fraser River ◽  
Initial Value ◽  
Spawning Grounds ◽  
Biochemical Studies

During the first 250 miles (400 km) of spawning migration of Fraser River sockeye salmon (Oncorhynchus nerka) the free histidine content of the muscle, alimentary tract, and head+skin+bones+tail decreased to a small fraction of the initial value. A further decrease occurred in the levels of this amino acid in the alimentary tract during the subsequent 415-mile (657-km) migration to the spawning grounds, no change being observed with the other tissues. Comparatively small changes in free histidine were found with heart, spleen, liver, kidney and gonads during migration.

A widespread decrease in productivity of sockeye salmon (Oncorhynchus nerka) populations in western North America

2012 ◽  
Vol 69 (8) ◽  
pp. 1255-1260 ◽  
Author(s):  
Randall M. Peterman ◽  
Brigitte Dorner
Keyword(s):  
Sockeye Salmon ◽  
Spatial Scales ◽  
Oncorhynchus Nerka ◽  
Geographic Area ◽  
Fraser River ◽  
Western North America ◽  
Southeast Alaska ◽  
The Past ◽  
Large Geographic Area ◽  
Marine Areas

We used data on 64 stocks of sockeye salmon ( Oncorhynchus nerka ) from British Columbia (B.C.), Washington, and Alaska to determine whether recent decreases in abundance and productivity observed for Fraser River, B.C., sockeye have occurred more widely. We found that decreasing time trends in productivity have occurred across a large geographic area ranging from Washington, B.C., southeast Alaska, and up through the Yakutat peninsula, Alaska, but not in central and western Alaska. Furthermore, a pattern of predominantly shared trends across southern stocks and opposite trends between them and stocks from western Alaska was present in the past (1950–1985), but correlations have intensified since then. The spatial extent of declining productivity of sockeye salmon has important implications for management as well as research into potential causes of the declines. Further research should focus on mechanisms that operate at large, multiregional spatial scales, and (or) in marine areas where numerous correlated sockeye stocks overlap.

Physiological and Growth Differences in Three Stocks of Underyearling Sockeye Salmon (Oncorhynchus nerka) on Early Entry into Seawater

1994 ◽  
Vol 51 (4) ◽  
pp. 974-980 ◽  
Author(s):  
Stanley D. Rice ◽  
Robert E. Thomas ◽  
Adam Moles
Keyword(s):  
Life History ◽  
Sockeye Salmon ◽  
Salt Water ◽  
Oncorhynchus Nerka ◽  
Early Life History ◽  
Life History Strategies ◽  
Growth Differences ◽  
The Impact ◽  
Lake Type ◽  
River Type

We compared the impact of exposure to seawater on three sockeye salmon (Oncorhynchus nerka) stocks: one that normally migrates to sea as underyearlings (sea-type) and two with the more common life history strategies of 1 (river-type) or 2 (lake-type) yr of freshwater residence prior to seaward migration. Innate differences in survival, ability to regulate tissue chlorides, and oxygen consumption when first introduced into salt water were more evident in April and May when fish were less than 50 mm in length. In fish longer than 50 mm, the only significant differences among the stocks were in saltwater growth. Between June and August, sea-type fish showed faster growth than river-type fish which in turn grew faster than lake-type fish. When introduced into salt water in October, virtually no growth occurred in any stock, regardless of fish size. River-type and lake-type sockeye, which normally overwinter 1 and 2 yr, respectively, in freshwater, can be reared in seawater if underyearlings are raised to a length of 50 mm before release into salt water, similar to the normal life history of sea-type underyearlings. Early life history appears to be influenced more by habitat than by genetics.

scholarly journals Pacific salmon abundance trends and climate change

2011 ◽  
Vol 68 (6) ◽  
pp. 1122-1130 ◽  
Author(s):  
James R. Irvine ◽  
Masa-aki Fukuwaka
Keyword(s):  
Climate Change ◽  
Pacific Ocean ◽  
North Pacific ◽  
Sockeye Salmon ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
North Pacific Ocean ◽  
Pink Salmon ◽  
The North ◽  
Abundance Trends

Abstract Irvine, J. R., and Fukuwaka, M. 2011. Pacific salmon abundance trends and climate change. – ICES Journal of Marine Science, 68: 1122–1130. Understanding reasons for historical patterns in salmon abundance could help anticipate future climate-related changes. Recent salmon abundance in the northern North Pacific Ocean, as indexed by commercial catches, has been among the highest on record, with no indication of decline; the 2009 catch was the highest to date. Although the North Pacific Ocean continues to produce large quantities of Pacific salmon, temporal abundance patterns vary among species and areas. Currently, pink and chum salmon are very abundant overall and Chinook and coho salmon are less abundant than they were previously, whereas sockeye salmon abundance varies among areas. Analyses confirm climate-related shifts in abundance, associated with reported ecosystem regime shifts in approximately 1947, 1977, and 1989. We found little evidence to support a major shift after 1989. From 1990, generally favourable climate-related marine conditions in the western North Pacific Ocean, as well as expanding hatchery operations and improving hatchery technologies, are increasing abundances of chum and pink salmon. In the eastern North Pacific Ocean, climate-related changes are apparently playing a role in increasing chum and pink salmon abundances and declining numbers of coho and Chinook salmon.

Arctic Plant Responses to Climate Warming: It’s Not all about Nitrogen

2018 ◽  
Author(s):  
Sanna Masud
Keyword(s):  
Climate Change ◽  
The Arctic ◽  
Plant Responses ◽  
Experimental Warming ◽  
Nutrient Pools ◽  
Research Attention ◽  
Low Arctic ◽  
Total Plant ◽  
The Impact ◽  
Deciduous Shrub

Climate change is increasing air and soil temperatures in the Arctic, likely enhancing microbial activity. Consequently, increased decomposition rates of soil organic matter and increasing nutrient supply to tundra vegetation can be expected. The impacts of experimental warming and fertilization on growth have been investigated by studying the availability of macronutrients such as N, P and C. However, other   macronutrients such as S, Ca, Mg, K, and micronutrients such as Fe, Mn, Cu, and Zn have received little research attention to determine their function, biogeochemical cycling, and effect on vegetation growth in response to warming. This study investigated the impact of experimental warming responses on availability and accumulation of the latter nutrients in the principal plant species located in mesic birch hummock tundra near Daring Lake, Northwest Territories in the Canadian Low Arctic Tundra. Plants were sampled in 2011 from the replicated summer greenhouse treatment that was established in 2004. In response to warming, the principal evergreen shrub (Rhododendron) had the most enhanced growth, followed by the deciduous shrub (Birch). Since the total plant pools of these nutrients were also enhanced in the evergreen, my results strongly suggest that availability of these nutrients was not limiting growth. By contrast, the birch total plant nutrient pools were not enhanced and significant decreases in Mg, S, and K leaf concentrations were observed, suggesting that these elements may be limiting birch growth. Together, our results suggest that plant growth response to climate change in the low Arctic may depend on previously overlooked nutrient elements, and that deciduous shrub growth may be constrained relative to the evergreen response as the arctic climate warms.

scholarly journals Variations in snowpack melt on the Greenland ice sheet based on passive-microwave measurements

1995 ◽  
Vol 41 (137) ◽  
pp. 51-60 ◽  
Author(s):  
Thomas L. Mote ◽  
Mark R. Anderson
Keyword(s):  
Climate Change ◽  
Ice Sheet ◽  
Greenland Ice Sheet ◽  
Ablation Rate ◽  
Passive Microwave ◽  
Microwave Emission ◽  
The Arctic ◽  
Emission Model ◽  
The Impact ◽  
Microwave Data

AbstractA simple microwave-emission model is used to simulate 37 GHz brightness temperatures associated with snowpack-melt conditions for locations across the Greenland ice sheet. The simulated values are utilized as threshold values and compared to daily, gridded SMMR and SSM/I passive-microwave data, in order to reveal regions experiencing melt. The spatial extent of the area classified as melting is examined on a daily, monthly and seasonal (May-August) basis for 1979–91. The typical seasonal cycle of melt coverage shows melt beginning in late April, a rapid increase in the melting area from mid-May to mid-July, a rapid decrease in melt extent from late July through mid-August, and cessation of melt in late September. Seasonal averages of the daily melt extents demonstrate an apparent increase in melt coverage over the 13 year period of approximately 3.8% annually (significant at the 95% confidence interval). This increase is dominated by statistically significant positive trends in melt coverage during July and August in the west and southwest of the ice sheet. We find that a linear correlation between microwave-derived melt extent and a surface measure of ablation rate is significant in June and July but not August, so caution must be exercised in using the microwave-derived melt extents in August. Nevertheless, knowledge of the variability of snowpack melt on the Greenland ice sheet as derived from microwave data should prove useful in detecting climate change in the Arctic and examining the impact of climate change on the ice sheet.

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