Assessment of CH4 sources in the Arctic using regional atmospheric measurements and their link to surface emissions

The Arctic is a critical area in terms of global warming. Not only are the rising temperatures already causing changes in the natural conditions of this region, but the high potential of increased methane (CH4) regional emissions are also likely to intensify global warming even stronger in the near term.This future effect consists in the thawing and destabilization of inland and sub-sea permafrost that enhance the release of methane into the atmosphere from extensive CH4 and organic carbon pools which have so far been shielded by ice and frozen soil. Moreover, the high latitude regions are already playing a key role in the global CH4-budget because of such large sources as wetlands and freshwater lakes in addition to human activities, predominantly the fossil fuel industry of the Arctic nations.However, the level of scientific understanding of the actual contribution of Arctic methane emissions to the global CH4-budget is still relatively immature. Besides the difficulties in carrying out measurements in such remote areas, this is due to a high inhomogeneity in the spatial distribution of methane sources and sinks as well as to ongoing changes in hydrology, vegetation and carbon decomposition.Therefore, the aim of this work is to reduce the uncertainties about methane sources and sinks in the Arctic region during the most recent years by using an atmospheric approach, in order to improve the quality of the assessment of the local and global impacts.To do so, the data of atmospheric CH4 concentrations measured at about 30 stations located in different Arctic nations have been analysed in regard to the trends, seasonal fluctuations and spatial patterns that they demonstrate as well as their link to regional emissions.

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Detectability of Arctic methane sources at six sites performing continuous atmospheric measurements

10.5194/acp-2017-169 ◽

2017 ◽

Cited By ~ 1

Author(s):

Thibaud Thonat ◽

Marielle Saunois ◽

Philippe Bousquet ◽

Isabelle Pison ◽

Zeli Tan ◽

...

Keyword(s):

Land Surface ◽

Transport Model ◽

Land Surface Model ◽

Arctic Region ◽

The Arctic ◽

Surface Model ◽

Multiple Sources ◽

Atmospheric Measurements ◽

Methane Cycle ◽

Methane Budget

Abstract. Understanding the recent evolution of methane emissions in the Arctic is necessary to interpret the global methane cycle. Emissions are affected by significant uncertainties and are sensitive to climate change, leading to potential feedbacks. A polar version of the CHIMERE chemistry-transport model is used to simulate the evolution of tropospheric methane in the Arctic during 2012, including all known regional anthropogenic and natural sources. CHIMERE simulations are compared to atmospheric continuous observations at six measurement sites in the Arctic region. In winter, the Arctic is dominated by anthropogenic emissions; emissions from continental seepages and oceans, including from the East Siberian Arctic Shelf, can contribute significantly in more limited areas. In summer, emissions from wetland and freshwater sources dominate across the whole region. The model is able to reproduce the seasonality and synoptic variations of methane measured at the different sites. We find that all methane sources significantly affect the measurements at all stations at least at the synoptic scale, except for biomass burning; this indicates the relevance of continuous observations to gain a mechanistic understanding of Arctic methane sources. Sensitivity tests reveal that the choice of the land surface model used to prescribe wetland emissions can be critical in correctly representing methane concentrations. Also testing different freshwater emission inventories leads to large differences in modelled methane. Attempts to include methane sinks (OH oxidation and soil uptake) reduced the model bias relative to observed atmospheric CH4. The study illustrates how multiple sources, having different spatiotemporal dynamics and magnitudes, jointly influence the overall Arctic methane budget, and highlights ways towards further improved assessments.

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Detectability of Arctic methane sources at six sites performing continuous atmospheric measurements

Atmospheric Chemistry and Physics ◽

10.5194/acp-17-8371-2017 ◽

2017 ◽

Vol 17 (13) ◽

pp. 8371-8394 ◽

Cited By ~ 11

Author(s):

Thibaud Thonat ◽

Marielle Saunois ◽

Philippe Bousquet ◽

Isabelle Pison ◽

Zeli Tan ◽

...

Keyword(s):

Land Surface ◽

Transport Model ◽

Land Surface Model ◽

Arctic Region ◽

The Arctic ◽

Surface Model ◽

Atmospheric Methane ◽

Multiple Sources ◽

Atmospheric Measurements ◽

Methane Cycle

Abstract. Understanding the recent evolution of methane emissions in the Arctic is necessary to interpret the global methane cycle. Emissions are affected by significant uncertainties and are sensitive to climate change, leading to potential feedbacks. A polar version of the CHIMERE chemistry-transport model is used to simulate the evolution of tropospheric methane in the Arctic during 2012, including all known regional anthropogenic and natural sources, in particular freshwater emissions which are often overlooked in methane modelling. CHIMERE simulations are compared to atmospheric continuous observations at six measurement sites in the Arctic region. In winter, the Arctic is dominated by anthropogenic emissions; emissions from continental seepages and oceans, including from the East Siberian Arctic Shelf, can contribute significantly in more limited areas. In summer, emissions from wetland and freshwater sources dominate across the whole region. The model is able to reproduce the seasonality and synoptic variations of methane measured at the different sites. We find that all methane sources significantly affect the measurements at all stations at least at the synoptic scale, except for biomass burning. In particular, freshwater systems play a decisive part in summer, representing on average between 11 and 26 % of the simulated Arctic methane signal at the sites. This indicates the relevance of continuous observations to gain a mechanistic understanding of Arctic methane sources. Sensitivity tests reveal that the choice of the land-surface model used to prescribe wetland emissions can be critical in correctly representing methane mixing ratios. The closest agreement with the observations is reached when using the two wetland models which have emissions peaking in August–September, while all others reach their maximum in June–July. Such phasing provides an interesting constraint on wetland models which still have large uncertainties at present. Also testing different freshwater emission inventories leads to large differences in modelled methane. Attempts to include methane sinks (OH oxidation and soil uptake) reduced the model bias relative to observed atmospheric methane. The study illustrates how multiple sources, having different spatiotemporal dynamics and magnitudes, jointly influence the overall Arctic methane budget, and highlights ways towards further improved assessments.

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Increased functional diversity warns of ecological transition in the Arctic

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2021.0054 ◽

2021 ◽

Vol 288 (1948) ◽

Author(s):

André Frainer ◽

Raul Primicerio ◽

Andrey Dolgov ◽

Maria Fossheim ◽

Edda Johannesen ◽

...

Keyword(s):

Global Warming ◽

Functional Diversity ◽

Barents Sea ◽

Arctic Region ◽

The Arctic ◽

Ecosystem Functions ◽

Arctic Species ◽

Increasing Trend ◽

Motile Species ◽

Ecological Transition

As temperatures rise, motile species start to redistribute to more suitable areas, potentially affecting the persistence of several resident species and altering biodiversity and ecosystem functions. In the Barents Sea, a hotspot for global warming, marine fish from boreal regions have been increasingly found in the more exclusive Arctic region. Here, we show that this shift in species distribution is increasing species richness and evenness, and even more so, the functional diversity of the Arctic. Higher diversity is often interpreted as being positive for ecosystem health and is a target for conservation. However, the increasing trend observed here may be transitory as the traits involved threaten Arctic species via predation and competition. If the pressure from global warming continues to rise, the ensuing loss of Arctic species will result in a reduction in functional diversity.

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Spatio-temporal variations of the atmospheric greenhouse gases and their sources and sinks in the Arctic region

Polar Science ◽

10.1016/j.polar.2020.100553 ◽

2020 ◽

pp. 100553

Author(s):

Shinji Morimoto ◽

Daisuke Goto ◽

Shohei Murayama ◽

Ryo Fujita ◽

Yasunori Tohjima ◽

...

Keyword(s):

Greenhouse Gases ◽

Arctic Region ◽

Temporal Variations ◽

The Arctic ◽

Sources And Sinks ◽

Spatio Temporal ◽

The Arctic Region

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Reconciling reported and unreported HFC emissions with atmospheric observations

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1420247112 ◽

2015 ◽

Vol 112 (19) ◽

pp. 5927-5931 ◽

Cited By ~ 33

Author(s):

Mark F. Lunt ◽

Matthew Rigby ◽

Anita L. Ganesan ◽

Alistair J. Manning ◽

Ronald G. Prinn ◽

...

Keyword(s):

Climate Change ◽

Global Warming ◽

United Nations ◽

Global Warming Potential ◽

Annual Reports ◽

Atmospheric Gases ◽

Atmospheric Measurements ◽

Hfc 134A ◽

Atmospheric Observations ◽

Regional Emissions

We infer global and regional emissions of five of the most abundant hydrofluorocarbons (HFCs) using atmospheric measurements from the Advanced Global Atmospheric Gases Experiment and the National Institute for Environmental Studies, Japan, networks. We find that the total CO2-equivalent emissions of the five HFCs from countries that are required to provide detailed, annual reports to the United Nations Framework Convention on Climate Change (UNFCCC) increased from 198 (175–221) Tg-CO2-eq⋅y–1 in 2007 to 275 (246–304) Tg-CO2-eq⋅y–1 in 2012. These global warming potential-weighted aggregated emissions agree well with those reported to the UNFCCC throughout this period and indicate that the gap between reported emissions and global HFC emissions derived from atmospheric trends is almost entirely due to emissions from nonreporting countries. However, our measurement-based estimates of individual HFC species suggest that emissions, from reporting countries, of the most abundant HFC, HFC-134a, were only 79% (63–95%) of the UNFCCC inventory total, while other HFC emissions were significantly greater than the reported values. These results suggest that there are inaccuracies in the reporting methods for individual HFCs, which appear to cancel when aggregated together.

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The imprint of stratospheric transport on column-averaged methane

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-15-20395-2015 ◽

2015 ◽

Vol 15 (14) ◽

pp. 20395-20447 ◽

Cited By ~ 3

Author(s):

A. Ostler ◽

R. Sussmann ◽

P. K. Patra ◽

P. O. Wennberg ◽

N. M. Deutscher ◽

...

Keyword(s):

Arctic Region ◽

Correction Method ◽

Total Carbon ◽

The Arctic ◽

Model Errors ◽

Atmospheric Measurements ◽

Model Simulations ◽

Mixing Ratios ◽

The Difference ◽

The Impact

Abstract. Model simulations of column-averaged methane mixing ratios (XCH4) are extensively used for inverse estimates of methane (CH4) emissions from atmospheric measurements. Our study shows that virtually all chemical transport models (CTM) used for this purpose are affected by stratospheric model-transport errors. We quantify the impact of such model transport errors on the simulation of stratospheric CH4 concentrations via an a posteriori correction method. This approach compares measurements of the mean age of air with modeled age and expresses the difference in terms of a correction to modeled stratospheric CH4 mixing ratios. We find age differences up to ~ 3 years yield to a bias in simulated CH4 of up to 250 parts per billion (ppb). Comparisons between model simulations and ground-based XCH4 observations from the Total Carbon Column Network (TCCON) reveal that stratospheric model-transport errors cause biases in XCH4 of ~ 20 ppb in the midlatitudes and ~ 27 ppb in the arctic region. Improved overall as well as seasonal model-observation agreement in XCH4 suggests that the proposed, age-of-air-based stratospheric correction is reasonable. The latitudinal model bias in XCH4 is supposed to reduce the accuracy of inverse estimates using satellite-derived XCH4 data. Therefore, we provide an estimate of the impact of stratospheric model-transport errors in terms of CH4 flux errors. Using a one-box approximation, we show that average model errors in stratospheric transport correspond to an overestimation of CH4 emissions by ~ 40 % (~ 7 Tg yr&minus;1) for the arctic, ~ 5 % (~ 7 Tg yr&minus;1) for the northern, and ~ 60 % (~ 7 Tg yr&minus;1) for the southern hemispheric mid-latitude region. We conclude that an improved modeling of stratospheric transport is highly desirable for the joint use with atmospheric XCH4 observations in atmospheric inversions.

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STORM ICE OIL WIND WAVE WATCH SYSTEM (SIOWS): WEB GIS APPLICATION FOR MONITORING THE ARCTIC

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.31519/conferencearticle_5b1b93852689d4.28131112 ◽

2017 ◽

Author(s):

Alexander Myasoedov ◽

Sergey Azarov ◽

Ekaterina Balashova ◽

...

Keyword(s):

Satellite Data ◽

Wind Wave ◽

Arctic Region ◽

Web Gis ◽

The Arctic ◽

Flexible Tool ◽

In Situ Data ◽

Current State ◽

Watch System

Working with satellite data, has long been an issue for users which has often prevented from a wider use of these data because of Volume, Access, Format and Data Combination. The purpose of the Storm Ice Oil Wind Wave Watch System (SIOWS) developed at Satellite Oceanography Laboratory (SOLab) is to solve the main issues encountered with satellite data and to provide users with a fast and flexible tool to select and extract data within massive archives that match exactly its needs or interest improving the efficiency of the monitoring system of geophysical conditions in the Arctic. SIOWS - is a Web GIS, designed to display various satellite, model and in situ data, it uses developed at SOLab storing, processing and visualization technologies for operational and archived data. It allows synergistic analysis of both historical data and monitoring of the current state and dynamics of the "ocean-atmosphere-cryosphere" system in the Arctic region, as well as Arctic system forecasting based on thermodynamic models with satellite data assimilation.

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Prévoir les variations saisonnières de la glace de mer arctique et leurs impacts sur le climat

La Météorologie ◽

10.37053/lameteorologie-2020-0089 ◽

2020 ◽

pp. 024

Author(s):

Rym Msadek ◽

Gilles Garric ◽

Sara Fleury ◽

Florent Garnier ◽

Lauriane Batté ◽

...

Keyword(s):

Sea Ice ◽

Arctic Region ◽

Arctic Sea Ice ◽

Climate Impacts ◽

The Arctic ◽

Recent Effort ◽

Sea Ice Thickness ◽

Arctic Sea ◽

Ice Conditions ◽

Upper Level

L'Arctique est la région du globe qui s'est réchauffée le plus vite au cours des trente dernières années, avec une augmentation de la température de surface environ deux fois plus rapide que pour la moyenne globale. Le déclin de la banquise arctique observé depuis le début de l'ère satellitaire et attribué principalement à l'augmentation de la concentration des gaz à effet de serre aurait joué un rôle important dans cette amplification des températures au pôle. Cette fonte importante des glaces arctiques, qui devrait s'accélérer dans les décennies à venir, pourrait modifier les vents en haute altitude et potentiellement avoir un impact sur le climat des moyennes latitudes. L'étendue de la banquise arctique varie considérablement d'une saison à l'autre, d'une année à l'autre, d'une décennie à l'autre. Améliorer notre capacité à prévoir ces variations nécessite de comprendre, observer et modéliser les interactions entre la banquise et les autres composantes du système Terre, telles que l'océan, l'atmosphère ou la biosphère, à différentes échelles de temps. La réalisation de prévisions saisonnières de la banquise arctique est très récente comparée aux prévisions du temps ou aux prévisions saisonnières de paramètres météorologiques (température, précipitation). Les résultats ayant émergé au cours des dix dernières années mettent en évidence l'importance des observations de l'épaisseur de la glace de mer pour prévoir l'évolution de la banquise estivale plusieurs mois à l'avance. Surface temperatures over the Arctic region have been increasing twice as fast as global mean temperatures, a phenomenon known as arctic amplification. One main contributor to this polar warming is the large decline of Arctic sea ice observed since the beginning of satellite observations, which has been attributed to the increase of greenhouse gases. The acceleration of Arctic sea ice loss that is projected for the coming decades could modify the upper level atmospheric circulation yielding climate impacts up to the mid-latitudes. There is considerable variability in the spatial extent of ice cover on seasonal, interannual and decadal time scales. Better understanding, observing and modelling the interactions between sea ice and the other components of the climate system is key for improved predictions of Arctic sea ice in the future. Running operational-like seasonal predictions of Arctic sea ice is a quite recent effort compared to weather predictions or seasonal predictions of atmospheric fields like temperature or precipitation. Recent results stress the importance of sea ice thickness observations to improve seasonal predictions of Arctic sea ice conditions during summer.

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

Voprosy regionalnoj ekonomiki ◽

10.21499/2078-4023-2018--4-110-113 ◽

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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