scholarly journals Detecting changes in Arctic methane emissions: limitations of the inter-polar difference of atmospheric mole fractions

2018 ◽  
Vol 18 (24) ◽  
pp. 17895-17907 ◽  
Author(s):  
Oscar B. Dimdore-Miles ◽  
Paul I. Palmer ◽  
Lori P. Bruhwiler
Keyword(s):  
Mole Fraction ◽  
Atmospheric Chemistry ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Random Noise ◽  
The Arctic ◽  
Polar Regions ◽  
Annual Growth Rate ◽  
Continuous Version ◽  
The Antarctic

Abstract. We consider the utility of the annual inter-polar difference (IPD) as a metric for changes in Arctic emissions of methane (CH4). The IPD has been previously defined as the difference between weighted annual means of CH4 mole fraction data collected at stations from the two polar regions (defined as latitudes poleward of 53∘ N and 53∘ S, respectively). This subtraction approach (IPD) implicitly assumes that extra-polar CH4 emissions arrive within the same calendar year at both poles. We show using a continuous version of the IPD that the metric includes not only changes in Arctic emissions but also terms that represent atmospheric transport of air masses from lower latitudes to the polar regions. We show the importance of these atmospheric transport terms in understanding the IPD using idealized numerical experiments with the TM5 global 3-D atmospheric chemistry transport model that is 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 mole fraction 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 IPD 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 approach would require data collected from all latitudes, emphasizing the importance of maintaining a global monitoring network to observe decadal changes in atmospheric greenhouse gases.

scholarly journals Detecting changes in Arctic methane emissions: limitations of the inter-polar difference of atmospheric mole fractions

2018 ◽  
Author(s):  
Oscar B. Dimdore-Miles ◽  
Paul I. Palmer ◽  
Lori P. Bruhwiler
Keyword(s):  
Atmospheric Chemistry ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Random Noise ◽  
Monitoring Network ◽  
The Arctic ◽  
Polar Regions ◽  
Annual Growth Rate ◽  
The Difference ◽  
The Antarctic

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.

scholarly journals A compilation of tropospheric measurements of gas-phase and aerosol chemistry in polar regions

2012 ◽  
Vol 5 (2) ◽  
pp. 585-705 ◽  
Author(s):  
R. Sander ◽  
J. Bottenheim
Keyword(s):  
Gas Phase ◽  
Atmospheric Chemistry ◽  
Temporal Trends ◽  
The Arctic ◽  
Polar Regions ◽  
Aerosol Chemistry ◽  
International Geophysical Year ◽  
Tropospheric Measurements ◽  
Spatial And Temporal Trends ◽  
The Antarctic

Abstract. Measurements of atmospheric chemistry in polar regions have been made for more than half a century. Probably the first Antarctic ozone data were recorded in 1958 during the International Geophysical Year. Since then, many measurement campaigns followed, and the results are now spread over many publications in several journals. Here, we have compiled measurements of tropospheric gas-phase and aerosol chemistry made in the Arctic and the Antarctic. It is hoped that this data collection is worth more than the sum of its components and serves as a basis for future analyses of spatial and temporal trends in polar atmospheric chemistry.

scholarly journals Mesosphere-to-stratosphere descent of odd nitrogen in February–March 2009 after sudden stratospheric warming

2011 ◽  
Vol 11 (10) ◽  
pp. 4645-4655 ◽  
Author(s):  
S.-M. Salmi ◽  
P. T. Verronen ◽  
L. Thölix ◽  
E. Kyrölä ◽  
L. Backman ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Polar Vortex ◽  
Polar Regions ◽  
Stratospheric Warming ◽  
Sudden Stratospheric Warming ◽  
Good Opportunity ◽  
Catalytic Ozone Destruction ◽  
Odd Nitrogen

Abstract. We use the 3-D FinROSE chemistry transport model (CTM) and Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) observations to study connections between atmospheric dynamics and middle atmospheric NOx (NOx = NO + NO2) distribution. Two cases are considered in the northern polar regions: (1) descent of mesospheric NOx in February–March 2009 after a major sudden stratospheric warming (SSW) and, for comparison, (2) early 2007 when no NOx descent occurred. The model uses the European Centre for Medium-Range Weather Forecasts (ECMWF) operational data for winds and temperature, and we force NOx at the model upper altitude boundary (80 km) with ACE-FTS observations. We then compare the model results with ACE-FTS observations at lower altitudes. For the periods studied, geomagnetic indices are low, which indicates absence of local NOx production by particle precipitation. This gives us a good opportunity to study effects of atmospheric transport on polar NOx. The model results show no NOx descent in 2007, in agreement with ACE-FTS. In contrast, a large amount of NOx descends in February–March 2009 from the upper to lower mesosphere at latitudes larger than 60° N, i.e. inside the polar vortex. Both observations and model results suggest NOx increases of 150–200 ppb (i.e. by factor of 50) at 65 km due to the descent. However, the model underestimates the amount of NOx around 55 km by 40–60 ppb. According to the model results, chemical loss of NOx is insignificant during the descent period, i.e. polar NOx is mainly controlled by dynamics. The descent is terminated and the polar NOx amounts return to pre-descent levels in mid-March, when the polar vortex breaks. The break-up prevents the descending NOx from reaching the upper stratosphere, where it could participate in catalytic ozone destruction. Both ACE-FTS observations and FinROSE show a decrease of ozone of 20–30 % at 30–50 km from mid-February to mid-March. In the model, these ozone changes are not related to the descent but are due to solar activation of halogen and NOx chemistry.

scholarly journals A compilation of tropospheric measurements of gas-phase and aerosol chemistry in polar regions

2012 ◽  
Vol 4 (1) ◽  
pp. 215-282 ◽  
Author(s):  
R. Sander ◽  
J. Bottenheim
Keyword(s):  
Gas Phase ◽  
Atmospheric Chemistry ◽  
Temporal Trends ◽  
The Arctic ◽  
Polar Regions ◽  
Aerosol Chemistry ◽  
International Geophysical Year ◽  
Tropospheric Measurements ◽  
Spatial And Temporal Trends ◽  
The Antarctic

Abstract. Measurements of atmospheric chemistry in polar regions have been made for more than half a century. Probably the first Antarctic ozone data were recorded in 1958 during the International Geophysical Year. Since then, many measurement campaigns followed, and the results are now spread over many publications in several journals. Here, we have compiled measurements of tropospheric gas-phase and aerosol chemistry made in the Arctic and the Antarctic. It is hoped that this data collection is worth more than the sum of its components and serves as a basis for future analyses of spatial and temporal trends in polar atmospheric chemistry.

scholarly journals Evolution in the cold

2000 ◽  
Vol 12 (3) ◽  
pp. 257-257 ◽  
Author(s):  
Andrew Clarke
Keyword(s):  
Evolutionary Biology ◽  
Antarctic Fish ◽  
The Arctic ◽  
Polar Regions ◽  
Evolutionary Studies ◽  
Adaptive Radiations ◽  
The Antarctic ◽  
The Impact ◽  
Insight Into

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.

scholarly journals BRICS in polar regions: Brazil’s interests and prospects

2020 ◽  
Vol 13 (3) ◽  
pp. 326-340
Author(s):  
Paulo Borba Casella ◽  
◽  
Maria Lagutina ◽  
Arthur Roberto Capella Giannattasio ◽  
◽  
...  
Keyword(s):  
Legal Regulation ◽  
The Arctic ◽  
Polar Regions ◽  
Arctic Council ◽  
Public Power ◽  
Promising Tool ◽  
Antarctic Treaty ◽  
International Power ◽  
Global Affairs ◽  
The Antarctic

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.

The Polar Regions and the Development of International Law: Contemporary Reflections and Twenty-First Century Challenges

2013 ◽  
Vol 5 (1) ◽  
pp. 233-251 ◽  
Author(s):  
Donald R. Rothwell
Keyword(s):  
International Law ◽  
First Century ◽  
The Arctic ◽  
Polar Regions ◽  
Foundational Research ◽  
Twenty First Century ◽  
Legal Frameworks ◽  
Global Affairs ◽  
The Antarctic ◽  
The Impact

Abstract The polar regions are increasingly coming to the forefront of global affairs in ways that are beginning to approach the prominence given to the polar regions during the ‘heroic era’ of exploration at the beginning of the twentieth century. This contemporary focus is, however, very much upon governance and the capacity of the existing and future legal frameworks to govern the Antarctic and Arctic effectively. This article revisits foundational research undertaken in 1992–1993 and reassesses the impact of the polar regions upon the development of international law. Particular attention is given to environmental management, living and nonliving resource management, the regulation and management of maritime areas, and governance mechanisms and frameworks. The article seeks to critically assess whether the existing legal frameworks that operate in Antarctica and the Arctic are capable of dealing with their increasing globalisation, or whether there will be a need for new legal and governance regimes to be developed to address twenty-first century challenges.

Polar tourism regulation strategies: controlling visitors through codes of conduct and legislation

Polar Record ◽  
1997 ◽  
Vol 33 (184) ◽  
pp. 13-20 ◽  
Author(s):  
Margaret E. Johnston
Keyword(s):  
Codes Of Conduct ◽  
Specific Area ◽  
Tourism Industry ◽  
The Arctic ◽  
Polar Regions ◽  
Regulation Strategies ◽  
Area Of Concern ◽  
Tourist Behaviour ◽  
The Antarctic ◽  
Further Development

AbstractControlling visitor impacts in polar regions continues to be important in both the Antarctic and Arctic. Concerns relate to impacts on the physical environment, cultural heritage, and host communities or scientific bases, as well as a recognition that safety and liability are major issues for governments, commercial operators, and local populations. Strategies for controlling tourists include visitor and operator codes and formal legislation. This paper summarises several approaches to visitor regulation in polar regions in order to illustrate the ways in which concerns about tourist impacts are being addressed. Similar issues arise throughout the polar regions, although in some places a particular emphasis might indicate a specific area of concern for a community, region, nation, or segment of the tourism industry. While a comprehensive strategy might be appropriate in many respects in the Arctic, it is also important to acknowledge the significance of more specific concerns. This paper first describes regulation of tourist behaviour and considers general issues of strategy effectiveness. Then it examines the approaches to visitor regulation used in the Antarctic and on S valbard as examples that may be of use in the further development of strategies in the Arctic. The paper then discusses an evolving strategy for control in the Northwest Territories, Canada. This strategy differs from these other approaches in that it targets a specific segment of the visitor population: those undertaking adventure expeditions.

scholarly journals Global emissions of HFC-143a (CH<sub>3</sub>CF<sub>3</sub>) and HFC-32 (CH<sub>2</sub>F<sub>2</sub>) from in situ and air archive atmospheric observations

2014 ◽  
Vol 14 (17) ◽  
pp. 9249-9258 ◽  
Author(s):  
S. O'Doherty ◽  
M. Rigby ◽  
J. Mühle ◽  
D. J. Ivy ◽  
B. R. Miller ◽  
...  
Keyword(s):  
Growth Rate ◽  
Mole Fraction ◽  
Radiative Forcing ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Lower Troposphere ◽  
Emission Rates ◽  
Global Emission ◽  
Atmospheric Observations

Abstract. High-frequency, in situ observations from the Advanced Global Atmospheric Gases Experiment (AGAGE), for the period 2003 to 2012, combined with archive flask measurements dating back to 1977, have been used to capture the rapid growth of HFC-143a (CH3CF3) and HFC-32 (CH2F2) mole fractions and emissions into the atmosphere. Here we report the first in situ global measurements of these two gases. HFC-143a and HFC-32 are the third and sixth most abundant hydrofluorocarbons (HFCs) respectively and they currently make an appreciable contribution to the HFCs in terms of atmospheric radiative forcing (1.7 ± 0.04 and 0.7 ± 0.02 mW m−2 in 2012 respectively). In 2012 the global average mole fraction of HFC-143a was 13.4 ± 0.3 ppt (1σ) in the lower troposphere and its growth rate was 1.4 ± 0.04 ppt yr−1; HFC-32 had a global mean mole fraction of 6.2 ± 0.2 ppt and a growth rate of 1.1 ± 0.04 ppt yr−1 in 2012. The extensive observations presented in this work have been combined with an atmospheric transport model to simulate global atmospheric abundances and derive global emission estimates. It is estimated that 23 ± 3 Gg yr−1 of HFC-143a and 21 ± 11 Gg yr−1 of HFC-32 were emitted globally in 2012, and the emission rates are estimated to be increasing by 7 ± 5% yr−1 for HFC-143a and 14 ± 11% yr−1 for HFC-32.

Arctic shipping guidelines: towards a legal regime for navigation safety and environmental protection?

Polar Record ◽  
2008 ◽  
Vol 44 (2) ◽  
pp. 107-114 ◽  
Author(s):  
Øystein Jensen
Keyword(s):  
The Arctic ◽  
Legal Issue ◽  
Polar Regions ◽  
International Polar Year ◽  
Safety Standards ◽  
International Polar ◽  
Key Issues ◽  
Arctic Ice ◽  
The Antarctic ◽  
Near Future

ABSTRACTWith the International Polar Year (IPY) having commenced in March 2007, key issues relating to the polar regions are again in focus. This article reviews one central legal issue re-emerging in the Arctic: global regulation of safety standards for international shipping. The ‘Guidelines for ships operating in Arctic ice-covered waters’ are examined, with a view to the probable expansion of shipping in the Arctic in near future. Following an introduction to navigational issues within the Arctic context, the article describes how the guidelines came into being, and then analyses key elements and structure of the regulations and shortfalls of today's arrangements. The possible relevance of the guidelines to the Antarctic is also discussed briefly. Finally, the article inquires into the key repercussions of introducing binding regulations.

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