Impacts of Greenland freshwater discharge on fjord productivity: a long-term perspective

2020 ◽  
Author(s):  
Mimmi Oksman ◽  
Anna Bang Kvorning ◽  
Sofia Ribeiro
Keyword(s):  
Marine Ecosystem ◽  
Sediment Cores ◽  
Greenland Ice Sheet ◽  
Arctic Region ◽  
Freshwater Discharge ◽  
The Arctic ◽  
Medieval Climate Anomaly ◽  
Marine Productivity ◽  
The Arctic Region

<p>In the past few decades, warming of the Arctic region has resulted in an abrupt increase of freshwater discharge from the Greenland Ice Sheet into its surrounding ocean. Greenland fjords are modulated by ice-ocean interactions and are very productive ecosystems that sustain important fisheries and other societal ecosystem services. While many studies are ongoing to understand seasonal and inter-annual changes, very little is known about the long-term impacts of freshwater discharge on primary producers and overall Arctic marine ecosystem functioning and structure. This long-term perspective is particularly important because freshwater runoff is expected to increase in the future along with rising atmospheric temperatures. Here, we present records from three marine sediment cores from the Godthåbsfjord that were used to reconstruct past marine productivity and freshwater discharge. The results based on diatom assemblages, BSi and TOC indicate marked fluctuations in past fjord productivity since the end of the Medieval Climate Anomaly, and periodical bursts of freshwater into the fjord resulting in a lowered productivity.</p>

scholarly journals Recent summer Arctic atmospheric circulation anomalies in a historical perspective

2015 ◽  
Vol 9 (1) ◽  
pp. 53-64 ◽  
Author(s):  
A. Belleflamme ◽  
X. Fettweis ◽  
M. Erpicum
Keyword(s):  
Atmospheric Circulation ◽  
Greenland Ice Sheet ◽  
Arctic Region ◽  
Reanalysis Data ◽  
Circulation Type ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Pressure Area ◽  
Circulation Anomalies ◽  
The Arctic Region

Abstract. A significant increase in the summertime occurrence of a high pressure area over the Beaufort Sea, the Canadian Arctic Archipelago, and Greenland has been observed since the beginning of the 2000s, and particularly between 2007 and 2012. These circulation anomalies are likely partly responsible for the enhanced Greenland ice sheet melt as well as the Arctic sea ice loss observed since 2007. Therefore, it is interesting to analyse whether similar conditions might have happened since the late 19th century over the Arctic region. We have used an atmospheric circulation type classification based on daily mean sea level pressure and 500 hPa geopotential height data from five reanalysis data sets (ERA-Interim, ERA-40, NCEP/NCAR, ERA-20C, and 20CRv2) to put the recent circulation anomalies in perspective with the atmospheric circulation variability since 1871. We found that circulation conditions similar to 2007–2012 have occurred in the past, despite a higher uncertainty of the reconstructed circulation before 1940. For example, only ERA-20C shows circulation anomalies that could explain the 1920–1930 summertime Greenland warming, in contrast to 20CRv2. While the recent anomalies exceed by a factor of 2 the interannual variability of the atmospheric circulation of the Arctic region, their origin (natural variability or global warming) remains debatable.

scholarly journals U.S. Arctic policy: the agenda of 2019

2020 ◽  
pp. 25-37
Author(s):  
Andrei Andreevich Kovalev
Keyword(s):  
United States ◽  
Arctic Region ◽  
The United States ◽  
Climatic Changes ◽  
The Arctic ◽  
Arctic Policy ◽  
Defense Cooperation ◽  
Relevant Consideration ◽  
The Arctic Region

This article explores the key stages of the development of U.S. policy with regards to Arctic Region. The goal is set to outline the fundamental interests of the United States in the Arctic, as well as analyze the actions aimed at their achievement. The article examines the main priorities in U.S. Arctic policy, namely the protection and preservation of resources and ecosystem in the Arctic Region, scientific study of climatic changes, peculiarities of economic development of Alaska, and national security interests of the state. The questions of interaction of Arctic states with regards to defense cooperation become increasingly relevant. Consideration of the mid-term and long-term prospects of U.S. Arctic policy allowed the author focusing attention on the news aspects of U.S. government actions. Maritime capabilities of the United States in the Arctic waters are views in the context of modern tendencies. The author attempted to trace the prospects for expansion of U.S. influence in the Arctic Region based on the current agenda of 2019.

scholarly journals China’s Arctic Policy: Challenges to Regional Security (1990s – 2020s)

2021 ◽  
pp. 377-388
Author(s):  
Oleksandr Horobets ◽  
Keyword(s):  
United States ◽  
Large Scale ◽  
Arctic Region ◽  
The United States ◽  
The Arctic ◽  
Regional Security ◽  
The World ◽  
Arctic Policy ◽  
The Arctic Region

The article analyzes the evolution of China's Arctic policy, which has expanded over three decades from individual polar research to observer status in the Arctic Council and the existence of a state Arctic strategy. China and Russia have established mutually beneficial cooperation in the Arctic region in such conditions, when in many areas there are fundamental contradictions between the countries. The West did not have a long-term strategy capable of responding to current security challenges, including in the Arctic. When Russia tried to regain lost positions on the world stage in 2007-2008, China became an increasingly influential player in the world. If before the Arctic had been outside the lines of rivalry for decades, the question of the Far North as an arena of military competition began to take first place. China has become a long-term threat to both the United States and Russia. In previous years, with the help of the China, Moscow had the opportunity to receive the necessary investments and technologies for large-scale Arctic projects. The more Beijing attempts to establish itself as an influential player in the Arctic, the more the threat to other Arctic countries will grow. The Russian Federation has positioned itself as a leader in the region. The country's policy was aimed at strengthening this status through regional control and expansion of the military presence. This led to a response from the United States and NATO countries. In Russia it was assessed as a threat. The question arises as to what the strategy of the United States should be, and whether it will be possible to resist the costly arms race. If not, then the competition will be concentrated in the political and economic spheres. A particular aspect is the rapid militarization of the Arctic region after 2014, primarily due to changes in Russia's military strategy, which extends to the North. This has led to the tensions between the United States and Russia. China has not yet resorted to expand its military power in the Arctic. China's policy of economic and infrastructural influence is opposed to military methods. The effectiveness of Chinese non-military methods of influence is assessed

scholarly journals Recent summer Arctic atmospheric circulation anomalies in a historical perspective

2014 ◽  
Vol 8 (5) ◽  
pp. 4823-4847 ◽  
Author(s):  
A. Belleflamme ◽  
X. Fettweis ◽  
M. Erpicum
Keyword(s):  
Sea Ice ◽  
Atmospheric Circulation ◽  
Greenland Ice Sheet ◽  
Arctic Region ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Arctic Sea ◽  
Circulation Anomalies ◽  
Arctic Sea Ice Loss ◽  
The Arctic Region

Abstract. A significant increase in the summertime occurrence of a high pressure area over the Beaufort Sea and Greenland has been observed from the beginning of the 2000's, and particularly between 2007 and 2012. These circulation anomalies are likely partly responsible for the enhanced Greenland ice sheet melt as well as the Arctic sea ice loss observed since 2007. Therefore, it is interesting to analyse whether similar conditions might have happened since the late 19th century over the Arctic region. We have used an atmospheric circulation type classification based on daily mean sea level pressure and 500 hPa geopotential height data from four reanalysis datasets (ERA-Interim, ERA-40, NCEP/NCAR, and 20CRv2) to put the recent circulation anomalies in perspective with the atmospheric circulation variability since 1871. We found that circulation conditions similar to 2007–2012 have occurred in the past, despite a higher uncertainty of the reconstructed circulation before 1940. But the recent anomalies largely exceed the interannual variability of the atmospheric circulation of the Arctic region. These circulation anomalies are linked with the North Atlantic Oscillation suggesting that they are not limited to the Arctic. Finally, they favour summertime Arctic sea ice loss.

Archaeology of the Eastern Aleut Region

2016 ◽  
Author(s):  
Herbert Maschner
Keyword(s):  
Bering Sea ◽  
North Pacific ◽  
Arctic Region ◽  
The Arctic ◽  
Human Populations ◽  
Key Factors ◽  
The Pacific ◽  
Marine Productivity ◽  
The One ◽  
The Arctic Region

The prehistory of the eastern Aleut region is one of the most convoluted and dynamic cultural trajectories in the Arctic region. Situated on the one of the world’s most productive fisheries, it is on the hinge point between the often-violent North Pacific and Bering Sea climate regimes. The richest marinescapes in the Pacific region gave rise to the largest human populations, the largest villages, and the most socially complex organizations in the Eskimo-Aleut world. But these villages rose and fell, and even the largest were subject to periodic cultural collapse. Climate, marine productivity, and boating technology are the key factors in understanding the archaeology of this part of Alaska.

scholarly journals Possible Effects of Sea Ice on Concrete Used in Arctic Conditions

Proceedings ◽  
2019 ◽  
Vol 34 (1) ◽  
pp. 13
Author(s):  
Vasiola Zhaka ◽  
Ankit Kothari ◽  
Andrzej Cwirzen
Keyword(s):  
Sea Ice ◽  
Freezing Point ◽  
Construction Material ◽  
Arctic Region ◽  
Weather Conditions ◽  
The Arctic ◽  
Arctic Conditions ◽  
Characterization Of Properties ◽  
The Arctic Region

The Arctic region is receiving an increasing attention due to the diminishing area of the permanent ice and easing access to various natural resources including especially oil, gas and rare metals. The nearest future will require building a significant number of new harbors and other structures related to sea operations and exploration. Harsh weather conditions including especially extreme freezing temperatures, snowfall and ice formation impose demanding requirements, which must be taken into account while designing, building and maintaining those structures. Concrete is the main construction material used for harbor structures. Unfortunately, the usage of Portland cement, which is the main cementitious binder used for concrete, it involves hardening processes, which are controlled by the hydration reactions. The hydration needs water and temperatures above freezing point, which impose serious limitations in the arctic environment. Furthermore, later exposure to the arctic conditions and especially to ice may impair its long-term durability and thus the sustainability of built structures. The present work focuses on characterization of properties of sea ice forming in harbors located in the Arctic region and on identification of possible implications on concrete material during the construction phase but also in long-term exploitation.

scholarly journals Cost-Effective Technologies to Study the Arctic Ocean Environment †

Sensors ◽  
2018 ◽  
Vol 18 (7) ◽  
pp. 2257 ◽  
Author(s):  
Viviana Piermattei ◽  
Alice Madonia ◽  
Simone Bonamano ◽  
Riccardo Martellucci ◽  
Gabriele Bruzzone ◽  
...  
Keyword(s):  
Arctic Ocean ◽  
Low Cost ◽  
Marine Ecosystem ◽  
Arctic Region ◽  
Extreme Environment ◽  
The Arctic ◽  
Svalbard Archipelago ◽  
The Arctic Ocean ◽  
The Impact ◽  
The Arctic Region

The Arctic region is known to be severely affected by climate change, with evident alterations in both physical and biological processes. Monitoring the Arctic Ocean ecosystem is key to understanding the impact of natural and human-induced change on the environment. Large data sets are required to monitor the Arctic marine ecosystem and validate high-resolution satellite observations (e.g., Sentinel), which are necessary to feed climatic and biogeochemical forecasting models. However, the Global Observing System needs to complete its geographic coverage, particularly for the harsh, extreme environment of the Arctic Region. In this scenario, autonomous systems are proving to be valuable tools for increasing the resolution of existing data. To this end, a low-cost, miniaturized and flexible probe, ArLoC (Arctic Low-Cost probe), was designed, built and installed on an innovative unmanned marine vehicle, the PROTEUS (Portable RObotic TEchnology for Unmanned Surveys), during a preliminary scientific campaign in the Svalbard Archipelago within the UVASS project. This study outlines the instrumentation used and its design features, its preliminary integration on PROTEUS and its test results.

Nuclear icebreaker fleet and power supply on the basis of floating power units

2018 ◽  
Vol 35 (4) ◽  
pp. 110-113
Author(s):  
V. A. Tupchienko ◽  
H. G. Imanova
Keyword(s):  
Foreign Policy ◽  
Power Supply ◽  
Nuclear Power ◽  
Arctic Region ◽  
Nuclear Industry ◽  
The Arctic ◽  
Far North ◽  
The Arctic Region

The article deals with the problem of the development of the domestic nuclear icebreaker fleet in the context of the implementation of nuclear logistics in the Arctic. The paper analyzes the key achievements of the Russian nuclear industry, highlights the key areas of development of the nuclear sector in the Far North, and identifies aspects of the development of mechanisms to ensure access to energy on the basis of floating nuclear power units. It is found that Russia is currently a leader in the implementation of the nuclear aspect of foreign policy and in providing energy to the Arctic region.

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