scholarly journals Arctic and Antarctic scleractinian сorals. Comparisons, the similarities and differences

2019 ◽  
Vol 59 (3) ◽  
pp. 413-420
Author(s):  
N. B. Keller ◽  
N. S. Oskina ◽  
T. А. Savilova

A comparison of the fauna of coldwater Scleractinia corals inhabiting the Polar regions of the Arctic and Antarctic revealed that in similar sub-zero temperatures of the surrounding waters, not only the character of the distribution of corals but also the number of species and their morphological characteristics in the Arctic and in the Antarctic radically different (in the sub-Antarctic region 17 coral species occure including 6 species endemic in the region, whereas the Arctic and high latitudes are inhabited by 2 species). We believe that the difference between these two faunas is due to the difference in geological history of these regions. In the southern hemisphere the formation of Circum-Antarctic currents ended the Neogene and in the sub-Antarctic region of stable conditions that existed millions of years that led to the formation of well-developed fauna scleractinia and the appearance of species endemic to this area. whereas in the Northern hemisphere hydrological stable conditions in high latitudes and the Arctic have existed since the beginning of the Holocene, approximately 11–12 thousand years, and when the colonization of corals by species of wide distribution.

2009 ◽  
Vol 1 (1) ◽  
pp. 145-174
Author(s):  
David Leary

Abstract Bioprospecting is occurring in the Arctic and Antarctica. This paper considers evidence on the nature and scale of bioprospecting in the Polar Regions. The paper then aims to draw out some of the critical issues in this debate by examining recent developments in the context of the Antarctic Treaty System. After an introduction to the history of the debate on bioprospecting in the Antarctic context it examines the recent Report of the Antarctic Treaty Consultative Meeting (‘ATCM’) Intersessional Contact Group to examine the issue of Biologocal Prospecting in the Antarctic Treaty Area tabled at ATCM XVII in Kiev in June 2008. The paper then concludes with some brief thoughts on the relevance of the Arctic experience to the debate in relation to Antarctica and whether or not there is an ‘Arctic Model’ for a response to the bioprospecting question in Antarctica. It is argued that rather than there being one Arctic model there is in fact a spectrum of models and experiences to choose from.


Polar Record ◽  
2003 ◽  
Vol 39 (4) ◽  
pp. 369-383 ◽  
Author(s):  
John S. Poland ◽  
Martin J. Riddle ◽  
Barbara A. Zeeb

Contaminants, in freezing ground or elsewhere in the world, are of concern not simply because of their presence but because of their potential for detrimental effects on human health, the biota, or other valued aspects of the environment. Understanding these effects is central to any attempt to manage or remediate contaminated land. The polar regions are different from other parts of the world, and it would be naïve to assume that the mass of information developed in temperate regions can be applied without modification to the polar regions. Despite their obvious environmental similarities, there are important differences between the Arctic and Antarctic. The landmass of the Arctic is much warmer than that of the Antarctic and as a result has a much greater diversity and abundance of flora. Because of its proximity to industrial areas in the Northern Hemisphere, the Arctic also experiences a higher input of contaminants via long-range aerial transport. In addition, the Arctic, with its indigenous population and generally undisputed territorial claims, has long been the subject of resource utilisation, including harvesting of living resources, mineral extraction, and the construction of military infrastructure. The history of human activity in Antarctica is relatively brief, but in this time there has been a series of quite distinct phases, culminating in the Antarctic now holding a unique position in the world. Activities in the Antarctic are governed by the Antarctic Treaty, which contains provisions dealing with environmental matters. The differences between the polar regions and the rest of the world, and between the Arctic and the Antarctic, significantly affect scientific and engineering approaches to the remediation of contamination in polar regions. This paper compares and contrasts the Arctic and Antarctic with respect to geography, configuration, habitation, logistics, environmental guidelines, regulations, and remediation protocols. Chemical contamination is also discussed in terms of its origin and major concerns and interests, particularly with reference to current remediation activities and site-restoration methodology.


2018 ◽  
Author(s):  
Oscar B. Dimdore-Miles ◽  
Paul I. Palmer ◽  
Lori P. Bruhwiler

Abstract. We consider the utility of the annual inter-polar difference (IPD) as a metric for changes in Arctic emission of methane (CH4). The IPD has been previously defined as the difference between weighted annual means of CH4 mole fraction data collected at polar stations (−53° > latitude > 53°). This subtraction approach (IPDΔ) implicitly assumes that extra-polar CH4 emissions arrive within the same calendar year at both poles. Using an analytic approach we show that a comprehensive description of the IPD includes terms corresponding to the atmospheric transport of air masses from lower latitudes to the polar regions. We show the importance of these transport flux terms in understanding the IPD using idealized numerical experiments with the TM5 global 3-D atmospheric chemistry transport model run from 1980 to 2010. A northern mid-latitude pulse in January 1990, which increases prior emission distributions, arrives at the Arctic with a higher mixing ratio and ≃ 12 months earlier than at the Antarctic. The perturbation at the poles subsequently decays with an e-folding lifetime of ≃ 4 years. A similarly timed pulse emitted from the tropics arrives with a higher value at the Antarctic ≃ 11 months earlier than at the Arctic. This perturbation decays with an e-folding lifetime of ≃ 7 years. These simulations demonstrate that the assumption of symmetric transport of extra-polar emissions to the poles is not realistic, resulting in considerable IPDΔ variations due to variations in emissions and atmospheric transport. We assess how well the annual IPD can detect a constant annual growth rate of Arctic emissions for three scenarios, 0.5 %, 1 %, and 2 %, superimposed on signals from lower latitudes, including random noise. We find that it can take up to 16 years to detect the smallest prescribed trend in Arctic emissions at the 95 % confidence level. Scenarios with higher, but likely unrealistic, growth in Arctic emissions are detected in less than a decade. We argue that a more reliable measurement-driven IPD metric would include data collected from all latitudes, emphasizing the importance of maintaining a global monitoring network to observe decadal changes in atmospheric greenhouse gases.


2015 ◽  
Vol 7 (1) ◽  
pp. 1-54
Author(s):  
Akiho Shibata

This paper examines whether core foundational principles can be distilled from the 100 years of history of the legal order-making in the polar regions. Despite differences in geo-physical, socio-historical, and legal circumstances conditioning the Antarctic and the Arctic regions, the examination of the processes of legal order-making in both polar regions demonstrates that there are some foundational principles being assessed and applied in designing their respective legal regimes. The identification of those core foundational principles would not necessarily lead to similar end products, nor would such examination necessarily advocate, for example, an Arctic Treaty System. This paper, instead, submits that between the Antarctic and the Arctic there are mutual learning processes already discernible at the foundational level of process legitimacy in international legal order-making. This examination also provides a broader framework to assess the existing literature that sees certain interactions between the two regimes at the level of substantive principles and rules.


2019 ◽  
Vol 32 (13) ◽  
pp. 3941-3956 ◽  
Author(s):  
Rune G. Graversen ◽  
Peter L. Langen

AbstractA doubling of the atmospheric CO2 content leads to global warming that is amplified in the polar regions. The CO2 forcing also leads to a change of the atmospheric energy transport. This transport change affects the local warming induced by the CO2 forcing. Using the Community Earth System Model (CESM), the direct response to the transport change is investigated. Divergences of the transport change associated with a CO2 doubling are implemented as a forcing in the 1 × CO2 preindustrial control climate. This forcing is zero in the global mean. In response to a CO2 increase in CESM, the northward atmospheric energy transport decreases at the Arctic boundary. However, the transport change still leads to a warming of the Arctic. This is due to a shift between dry static and latent transport components, so that although the dry static transport decreases, the latent transport increases at the Arctic boundary, which is consistent with other model studies. Because of a greenhouse effect associated with the latent transport, the cooling caused by a change of the dry static component is more than compensated for by the warming induced by the change of the latent transport. Similar results are found for the Antarctic region, but the transport change is larger in the Southern Hemisphere than in its northern counterpart. As a consequence, the Antarctic region warms to the extent that this warming leads to global warming that is likely enhanced by the surface albedo feedback associated with considerable ice retreat in the Southern Hemisphere.


2000 ◽  
Vol 12 (3) ◽  
pp. 257-257 ◽  
Author(s):  
Andrew Clarke

Theodosius Dobzhansky once remarked that nothing in biology makes sense other than in the light of evolution, thereby emphasising the central role of evolutionary studies in providing the theoretical context for all of biology. It is perhaps surprising then that evolutionary biology has played such a small role to date in Antarctic science. This is particularly so when it is recognised that the polar regions provide us with an unrivalled laboratory within which to undertake evolutionary studies. The Antarctic exhibits one of the classic examples of a resistance adaptation (antifreeze peptides and glycopeptides, first described from Antarctic fish), and provides textbook examples of adaptive radiations (for example amphipod crustaceans and notothenioid fish). The land is still largely in the grip of major glaciation, and the once rich terrestrial floras and faunas of Cenozoic Gondwana are now highly depauperate and confined to relatively small patches of habitat, often extremely isolated from other such patches. Unlike the Arctic, where organisms are returning to newly deglaciated land from refugia on the continental landmasses to the south, recolonization of Antarctica has had to take place by the dispersal of propagules over vast distances. Antarctica thus offers an insight into the evolutionary responses of terrestrial floras and faunas to extreme climatic change unrivalled in the world. The sea forms a strong contrast to the land in that here the impact of climate appears to have been less severe, at least in as much as few elements of the fauna show convincing signs of having been completely eradicated.


Atmosphere ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1494
Author(s):  
Fernanda Casagrande ◽  
Francisco A. B. Neto ◽  
Ronald B. de Souza ◽  
Paulo Nobre

One of the most visible signs of global warming is the fast change in the polar regions. The increase in Arctic temperatures, for instance, is almost twice as large as the global average in recent decades. This phenomenon is known as the Arctic Amplification and reflects several mutually supporting processes. An equivalent albeit less studied phenomenon occurs in Antarctica. Here, we used numerical climate simulations obtained from CMIP5 and CMIP6 to investigate the effects of +1.5, 2 and 3 °C warming thresholds for sea ice changes and polar amplification. Our results show robust patterns of near-surface air-temperature response to global warming at high latitudes. The year in which the average air temperatures brought from CMIP5 and CMIP6 models rises by 1.5 °C is 2024. An average rise of 2 °C (3 °C) global warming occurs in 2042 (2063). The equivalent warming at northern (southern) high latitudes under scenarios of 1.5 °C global warming is about 3 °C (1.8 °C). In scenarios of 3 °C global warming, the equivalent warming in the Arctic (Antarctica) is close to 7 °C (3.5 °C). Ice-free conditions are found in all warming thresholds for both the Arctic and Antarctica, especially from the year 2030 onwards.


2020 ◽  
Vol 13 (3) ◽  
pp. 326-340
Author(s):  
Paulo Borba Casella ◽  
◽  
Maria Lagutina ◽  
Arthur Roberto Capella Giannattasio ◽  
◽  
...  

The current international legal regulation of the Arctic and Antarctica was organized during the second half of the XX century to establish an international public power over the two regions, the Arctic Council (AC) and the Antarctic Treaty System (ATS), which is characterized by Euro-American dominance. However, the rise of emerging countries at the beginning of the XXI century suggests a progressive redefinition of the structural balance of international power in favor of states not traditionally perceived as European and Western. This article examines the role of Brazil within the AC and the ATS to address various polar issues, even institutional ones. As a responsible country in the area of cooperation in science and technology in the oceans and polar regions in BRICS, Brazil appeals to its rich experience in Antarctica and declares its interest in joining the Arctic cooperation. For Brazil, participation in polar cooperation is a way to increase its role in global affairs and BRICS as a negotiating platform. It is seen in this context as a promising tool to achieve this goal. This article highlights new paths in the research agenda concerning interests and prospects of Brazilian agency in the polar regions.


2007 ◽  
Vol 7 (4) ◽  
pp. 10837-10931 ◽  
Author(s):  
A. Steffen ◽  
T. Douglas ◽  
M. Amyot ◽  
P. Ariya ◽  
K. Aspmo ◽  
...  

Abstract. It was discovered in 1995 that, during the spring time, unexpectedly low concentrations of gaseous elemental mercury (GEM) occurred in the Arctic air. This was surprising for a pollutant known to have a long residence time in the atmosphere; however conditions appeared to exist in the Arctic that promoted this depletion of mercury (Hg). This phenomenon is termed atmospheric mercury depletion events (AMDEs) and its discovery has revolutionized our understanding of the cycling of Hg in Polar Regions while stimulating a significant amount of research to understand its impact to this fragile ecosystem. Shortly after the discovery was made in Canada, AMDEs were confirmed to occur throughout the Arctic, sub-Artic and Antarctic coasts. It is now known that, through a series of photochemically initiated reactions involving halogens, GEM is converted to a more reactive species and is subsequently associated to particles in the air and/or deposited to the polar environment. AMDEs are a means by which Hg is transferred from the atmosphere to the environment that was previously unknown. In this article we review the history of Hg in Polar Regions, the methods used to collect Hg in different environmental media, research results of the current understanding of AMDEs from field, laboratory and modeling work, how Hg cycles around the environment after AMDEs, gaps in our current knowledge and the future impacts that AMDEs may have on polar environments. The research presented has shown that while considerable improvements in methodology to measure Hg have been made the main limitation remains knowing the speciation of Hg in the various media. The processes that drive AMDEs and how they occur are discussed. As well, the roles that the snow pack, oceans, fresh water and the sea ice play in the cycling of Hg are presented. It has been found that deposition of Hg from AMDEs occurs at marine coasts and not far inland and that a fraction of the deposited Hg does not remain in the same form in the snow. Kinetic studies undertaken have demonstrated that bromine is the major oxidant depleting Hg in the atmosphere. Modeling results demonstrate that there is a significant deposition of Hg to Polar Regions as a result of AMDEs. Models have also shown that Hg is readily transported to the Arctic from source regions, at times during springtime when this environment is actively transforming Hg from the atmosphere to the snow and ice surfaces. The presence of significant amounts of methyl Hg in snow in the Arctic surrounding AMDEs is important because this species is the link between the environment and impacts to wildlife and humans. Further, much work on methylation and demethylation processes have occurred but are not yet fully understood. Recent changes in the climate and sea ice cover in Polar Regions are likely to have strong effects on the cycling of Hg in this environment; however more research is needed to understand Hg processes in order to formulate meaningful predictions of these changes. Mercury, Atmospheric mercury depletion events (AMDE), Polar, Arctic, Antarctic, Ice


Author(s):  
E. W. Sexton

Gammarus zaddachi is perhaps the most prolific and widespread of all the estuarine amphipods known to occur in northern Europe, and inhabiting, as it does, the low-salinity estuarine zone and adjacent coasts, it has come to be recognized in recent ecological work as a ‘salinity indicator’.Unfortunately, there has been constant confusion with the other common species of Gammarus, G. locusta, pulex, and duebeni, which has been greatly complicated by the difference in the appearance of zaddachi according as it lives in a freshwater or a saline habitat. It is shown that this difference is entirely due to the sensory equipment, the greater production of hairs in freshwater conditions, and that the structure of the two ‘forms’ is identical.The history of the species has been carried back as far as I have been able to trace it (1836) with the actual specimens, described in the different papers, and the more important of these papers are discussed. It will be seen that the material examined was derived from every country of northern Europe; from Russia, the White Sea, Crimea, and the Baltic, the coasts of Scandinavia, Germany, including the Hamburg water-supply, Denmark, the Netherlands, Great Britain and Ireland, and France as far up the Loire as Nantes.Detailed descriptions and figures of both forms of G. zaddachi are given; and finally, a comparison is made between the species most commonly confused with it, the Arctic species G. wilkitzkii being included because of a suggestion recently made that it might be, not a distinct species, but merely the Arctic form of zaddachi.


Sign in / Sign up

Export Citation Format

Share Document