SOME RESULTS OF GREENHOUSE GAS ATMOSPHERIC CONCENTRATIONS MEASUREMENTS IN THE RUSSIAN ARCTIC IN JULY DECEMBER 2017

AbstractLakes and reservoirs contribute substantially to atmospheric concentrations of the potent greenhouse gas methane. Lacustrine sediments produce large amounts of methane, which accumulate in oxygen-depleted hypolimnia of stratified lakes. Due to climate change and progressing eutrophication, the number of lakes with hypolimnetic methane storage may increase in the future. However, whether stored methane eventually reaches the atmosphere during lake overturn is a matter of controversy and depends critically on the response of the methanotroph assemblage. We show that the methanotroph assemblage in a mixing lake underwent both a substantial bloom and ecological succession. As a result, the methane oxidation capacity of the mixed layer kept pace with the methane supplied from the hypolimnion and most of the stored methane was oxidized. This previously unknown aspect of freshwater methanotroph ecology represents an effective mechanism limiting methane transfer from lakes to the atmosphere.

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Greenhouse gas emissions (CO2, CH4 and N2O) from perialpine and alpine hydropower reservoirs

Biogeosciences Discussions ◽

10.5194/bgd-5-3699-2008 ◽

2008 ◽

Vol 5 (5) ◽

pp. 3699-3736 ◽

Cited By ~ 3

Author(s):

T. Diem ◽

S. Koch ◽

S. Schwarzenbach ◽

B. Wehrli ◽

C. J. Schubert

Keyword(s):

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Gas Emissions ◽

Wind Speeds ◽

Trace Gas Emissions ◽

Lowland Reservoirs ◽

Lowland Reservoir ◽

The Alps ◽

Ch4 And N2o ◽

Atmospheric Concentrations

Abstract. In eleven reservoirs located at different altitudes in Switzerland depth profiles of greenhouse gas (CO2, CH4, and N2O) concentrations were measured several times during spring and summer. Trace gas emissions were calculated using surface concentrations, wind speeds and transfer velocities. Additionally we assessed methane loss at the turbine and the methane input by inflowing water. All reservoirs were net emitters of CO2 with an average of 1030±780 mg m−2 d−1 and of methane with an average of 0.20±0.15 mg m−2 d−1. One reservoir (Lake Wohlen) emitted methane at a much higher rate (160±110 mg m−2 d−1), most of which (>98%) was due to ebullition. Only lowland reservoirs were sources for N2O (72±22 μg m−2 d−1), while the subalpine and alpine reservoirs seem to be in equilibrium with atmospheric concentrations. Methane loss at the turbine was as large as the diffusive flux from the surface for two subalpine reservoirs and around five times smaller for a lowland reservoir. The available data suggests greenhouse gas emissions from reservoirs in the Alps are minor contributors to the global greenhouse gas emissions.

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Emissions halted of the potent greenhouse gas SF5CF3

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-12-869-2012 ◽

2012 ◽

Vol 12 (1) ◽

pp. 869-885 ◽

Cited By ~ 1

Author(s):

W. T. Sturges ◽

D. E. Oram ◽

J. C. Laube ◽

C. E. Reeves ◽

M. J. Newland ◽

...

Keyword(s):

Greenhouse Gas ◽

Aircraft Measurements ◽

Long Lifetime ◽

The 1950S ◽

Atmospheric Concentrations ◽

Background Air ◽

Cape Grim

Abstract. Long term measurements in background air (Cape Grim, Tasmania) and firn air (NEEM, Greenland) of the "super" greenhouse gas SF5CF3 show that emissions declined after the late 1990s, having grown since the 1950s, and became indistinguishable from zero after 2003. It is concluded that this is due to the cessation of global production of perfluorooctyl sulfonate-based fluorochemicals. An earlier observation of closely correlated atmospheric abundances of SF5CF3 and SF6 are shown here to have likely been purely coincidental, as their respective trends diverged after 2002. Due to its long lifetime (ca. 900 yr), atmospheric concentrations of SF5CF3 have not declined, and it is now well mixed between hemispheres, as is also shown here from interhemispheric aircraft measurements. Total cumulative emissions of SF5CF3 amount to around 5 kT.

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Emissions halted of the potent greenhouse gas SF5CF3

Atmospheric Chemistry and Physics ◽

10.5194/acp-12-3653-2012 ◽

2012 ◽

Vol 12 (8) ◽

pp. 3653-3658 ◽

Cited By ~ 19

Author(s):

W. T. Sturges ◽

D. E. Oram ◽

J. C. Laube ◽

C. E. Reeves ◽

M. J. Newland ◽

...

Keyword(s):

Greenhouse Gas ◽

Aircraft Measurements ◽

Long Lifetime ◽

The 1950S ◽

Atmospheric Concentrations ◽

Background Air ◽

Cape Grim

Abstract. Long term measurements in background air (Cape Grim, Tasmania) and firn air (NEEM, Greenland) of the potent long-lived greenhouse gas SF5CF3 show that emissions declined after the late 1990s, having grown since the 1950s, and became indistinguishable from zero after 2003. The timing of this decline suggests that emissions of this gas may have been related to the production of certain fluorochemicals; production of which have been recently phased out. An earlier observation of closely correlated atmospheric abundances of SF5CF3 and SF6 are shown here to have likely been purely coincidental, as their respective trends diverged after 2002. Due to its long lifetime (ca. 900 yr), atmospheric concentrations of SF5CF3 have not declined, and it is now well mixed between hemispheres, as is also shown here from interhemispheric aircraft measurements. Total cumulative emissions of SF5CF3 amount to around 5 kT.

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