Sentences with phrase «atmospheric emissions of methane»

Not exact matches

However, newer research has shown that GHG emissions such as atmospheric methane have risen rapidly since 2007, according to a 2016 study published in the International Journal of Science.
«These studies are a wake - up call ahead of U.N. Climate Week — we must not only zero out CO2 emissions by 2050, but also rapidly limit superpollutants like HFCs and methane, and even undertake atmospheric carbon removal,» said Bledsoe, a former Clinton White House climate adviser.
During the early 2000s, environmental scientists studying methane emissions noticed something unexpected: the global concentrations of atmospheric methane (CH4)-- which had increased for decades, driven by methane emissions from fossil fuels and agriculture — inexplicably leveled off.
A surprising recent rise in atmospheric methane likely stems from wetland emissions, suggesting that much more of the potent greenhouse gas will be pumped into the atmosphere as northern wetlands continue to thaw and tropical ones to warm, according to a new international study led by a University of Guelph researcher.
In the new paper, published in the journal Environmental Research Letters, Höglund - Isaksson estimated global methane emissions from oil and gas systems in over 100 countries over a 32 - year period, using a variety of country - specific data ranging from reported volumes of associated gas to satellite imagery that can show flaring, as well as atmospheric measurements of ethane, a gas which is released along with methane and easier to link more directly to oil and gas activities.
«If we want natural gas to be the cleanest fossil fuel source, methane emissions have to be reduced,» says Gabrielle Pétron, an atmospheric scientist at NOAA and at the University of Colorado in Boulder, and first author on the study, currently in press at the Journal of Geophysical Research.
Although the emission remains a mystery, it may arise from the fluorescence of atmospheric methane, a phenomenon witnessed in our own solar system.
It's correct that an extra methane molecule is something like 25 times more influential than an extra CO2 molecule, although that ratio is primarily determined by the background atmospheric concentration of either gas, and GWP typically assumes that forcing is linear in emission pulse, which is not valid for very large perturbations.
The Arctic Monitoring and Assessment Program (AMAP) carbon assessment published in 2009 highlighted the disparity in methane emissions estimated by extrapolating data from wetlands, lakes, and coastal waters underlain by permafrost (32 to 112 Tg CH4 yr - 1) and estimates based on spatial and temporal variability of atmospheric methane concentrations (15 to 50 Tg CH4 yr - 1).
Bruhwiler, L., et al. (2014), CarbonTracker - CH4: An assimilation system for estimating emissions of atmospheric methane, Atmos.
There is an urgent need to better reconcile bottom - up estimates with atmospheric estimates of methane emissions.
Raymond Pierrehumbert, an Oxford University atmospheric physics professor who believes cutting carbon dioxide emissions is more urgent than cutting methane emissions, said Howarth's research offers little new information about the role of natural gas production in global warming.
The study shows that during drilling, as much as 34 grams of methane per second were spewing into the air from seven natural gas well pads in southwest Pennsylvania — up to 1,000 times the EPA estimate for methane emissions during drilling, Purdue atmospheric chemistry professor and study lead author Paul Shepson said in a statement.
We find (i) measurements at all scales show that official inventories consistently underestimate actual CH4 [methane] emissions, with the natural gas and oil sectors as important contributors; (ii) many independent experiments suggest that a small number of «super-emitters» could be responsible for a large fraction of leakage; (iii) recent regional atmospheric studies with very high emissions rates are unlikely to be representative of typical natural gas system leakage rates; and (iv) assessments using 100 - year impact indicators show system - wide leakage is unlikely to be large enough to negate climate benefits of coal - to - natural gas substitution.
• The methanetrack.org website has shown significant increases in atmospheric methane concentrations over Antarctica this austral winter (which I believe are due to increases in methane emissions from the Southern Ocean seafloor due to increases in the temperature of bottom water temperatures), and if this trend continues, then the Southern Hemisphere could be a significant source of additional atmospheric methane (this century).
First estimates of ESAS methane emissions indicated the current atmospheric budget, which arises from gradual diffusion and ebullition, was on par with estimates of methane emissions from the entire World Ocean (≈ 8 Tg - CH4).
As NOAA's Mauna Loa measurement of atmospheric methane concentrations are only currently increasing at a rate of approximately 0.25 % per year (or 12.5 % change in 50 - years); how could anyone be concerned that the change in atmospheric methane burden in 50 - years could be 300 % (as per Isaken et al (2011) case 4XCH4; which would require an additional 0.80 GtCH4 / yr of methane emissions on top of the current rate of methane emissions of 0.54 GtCH4 / yr)?
As an example of the possible extreme change in radiative forcing in a 50 - year time horizon for Isaken et al (2011)'s 4 x CH4 (i.e. quadrupling the current atmospheric methane burden) case of additional emission of 0.80 GtCH4 / yr is 2.2 Wm - 2, and as the radiative forcing for the current methane emissions of 0.54 GtCH4 / yr is 0.48 Wm - 2, this give an updated GWP for methane, assuming the occurrence of Isaksen et al's 4 x CH4 case in 2040, would be: 33 (per Shindell et al 2009, note that AR5 gives a value of 34) times (2.2 / [0.8 + 0.48]-RRB- divided by (0.54 / 0.48) = 50.
2011) of the present atmospheric methane burden by 2100, or a 50 % increase fifty years primarily due to increase emissions from marshlands and conventional anthropogenic sources.
Ed Dlugokencky of NOAA, who confirmed a couple of weeks ago that recent increases in atmospheric methane were continuing, tells me that the emissions estimates are reasonable, but that the global data is not yet consistent with a large and growing source of Arctic methane....»
The IPCC Third Assessment Report's (TAR's) projections for methane atmospheric concentrations, carbon dioxide emissions and atmospheric concentrations, and resultant temperature increases constitute the greatest fraud in the history of environmental science.
More importantly, the atmospheric methane flux from the Arctic Ocean is really small (extrapolating estimates from Kort et al 2012), even compared with emissions from the Arctic land surface, which is itself only a few percent of global emissions (dominated by human sources and tropical wetlands).
In the short - term, a key issue that needs resolving is the mismatch between global methane budgets from top - down (derived from atmospheric measurements) and bottom - up (derived from measurements of methane emissions at the land surface from different methane producing environments) approaches.
Bruhwiler, L., et al. (2014), CarbonTracker - CH4: An assimilation system for estimating emissions of atmospheric methane, Atmos.
This presupposes that all of the atmospheric CO2 increase is of anthropogenic origin without regard to increases from non-anthropogenic sources such as changes in phytoplankton, volcanic eruptions, breakdown of methane emissions, deep ocean turnover, etc..
Using SCIAMACHY satellite data as well as ground - based measurements from 2003 to 2009, researchers found that the region where Arizona, New Mexico, Colorado, and Utah intersect had atmospheric methane concentrations equivalent to about 1.3 million pounds of emissions a year.
The IPCC Third Assessment Report projections for atmospheric methane concentrations, CO2 emissions and atmospheric concentrations, and resultant temperature increases (i.e. 1.4 to 5.8 degrees Celsius from 1990 to 2100) constitute the greatest fraud in the history of environmental science:
Instead atmospheric physics uses the fundamental equations (the radiative transfer equations) which determine absorption and emission of radiation by water vapor, CO2, methane, and other trace gases.
The study found that U.S. methane emissions could account for 30 to 60 percent of the global growth of atmospheric methane over the past decade.
Industry, with the full support of the administration, continues the fait accompli of radically expanded natural gas fracking across the country, with serious unresolved issues about fugitive atmospheric methane emissions and the potential for contamination of drinking water aquifers — and with no adequate federal regulatory structure in place.
Methane and nitrous oxide emissions from agriculture and other human activities add to the atmospheric burden of heat - trapping gases.
Reductions in some short - lived human - induced emissions that contribute to warming, such as black carbon (soot) and methane, could reduce some of the projected warming over the next couple of decades, because, unlike carbon dioxide, these gases and particles have relatively short atmospheric lifetimes.The amount of warming projected beyond the next few decades is directly linked to the cumulative global emissions of heat - trapping gases and particles.
«According to the Clathrate Gun Hypothesis (Kennett et al., submitted) episodic atmospheric CH4 emissions resulting from instability of the marine sedimentary methane hydrate (clathrate) reservoir contributed significantly to the distinctive behavior of late Quaternary climate on orbital (Milankovitch) and millennial time scales.
AER scientists contributed atmospheric transport modeling and research expertise to the new study by Harvard University, which is «the first of its kind to quantify methane emissions from natural gas leaks in an urban area».
Any loss of permafrost would increase atmospheric emissions of carbon dioxide and methane, fuelling further warming.
Simultaneous observations of atmospheric ethane, compared with the ethane - to - methane ratio in the pipeline gas delivered to the region, demonstrate that natural gas accounted for ∼ 60 — 100 % of methane emissions, depending on season.
Methane is an important part of the anthropogenic radiative forcing Methane emissions have a direct GHG effect, and they effect atmospheric chemistry and stratospheric water vapour which have additional impacts natural feedbacks involving methane likely to be important in future — via wetland response to temperature / rain change, atmospheric chemistry and, yes, arctic sources There are large stores of carbon in the Arctic, some stored as hydrates, some potentially convertible to CH4 by anaerobic resporation [from wikianswers: Without Methane is an important part of the anthropogenic radiative forcing Methane emissions have a direct GHG effect, and they effect atmospheric chemistry and stratospheric water vapour which have additional impacts natural feedbacks involving methane likely to be important in future — via wetland response to temperature / rain change, atmospheric chemistry and, yes, arctic sources There are large stores of carbon in the Arctic, some stored as hydrates, some potentially convertible to CH4 by anaerobic resporation [from wikianswers: Without Methane emissions have a direct GHG effect, and they effect atmospheric chemistry and stratospheric water vapour which have additional impacts natural feedbacks involving methane likely to be important in future — via wetland response to temperature / rain change, atmospheric chemistry and, yes, arctic sources There are large stores of carbon in the Arctic, some stored as hydrates, some potentially convertible to CH4 by anaerobic resporation [from wikianswers: Without methane likely to be important in future — via wetland response to temperature / rain change, atmospheric chemistry and, yes, arctic sources There are large stores of carbon in the Arctic, some stored as hydrates, some potentially convertible to CH4 by anaerobic resporation [from wikianswers: Without oxygen.
This parallels a recent NOAA study of atmospheric methane measurements that found that «methane emissions from natural gas as a fraction of production have declined from approximately 8 per cent to approximately 2 per cent over the past three decades» — with production soaring in recent years.
Not only is the atmospheric impact of the current leak considerable (in three months the well had already released «more greenhouse gases than any other facility in California,» and already «more than doubled the methane emissions of the entire Los Angeles Basin and surpassed what is released by all industrial activity in the state.»)
Translating across discipline - specific vocabularies was essential to understanding mismatches in estimates of methane emissions from permafrost based on field measurements and on atmospheric data.
The effect of this increase on the growth rate of atmospheric methane has been masked by a coincident decrease in wetland emissions, but atmospheric methane levels may increase in the near future if wetland emissions return to their mean 1990s levels.
So any of the IPCC projections of future emissions that include ANY increase in atmospheric methane are in very serious error.
Two studies published in April 2017 suggest that recent increases in atmospheric concentrations of methane may not be caused by increasing emissions.
Here we quantify the processes that controlled variations in methane emissions between 1984 and 2003 using an inversion model of atmospheric transport and chemistry.
the atmospheric methane flux from the Arctic Ocean is really small (extrapolating estimates from Kort et al 2012), even compared with emissions from the Arctic land surface, which is itself only a few percent of global emissions (dominated by human sources and tropical wetlands).
Research published in Science shows that up to 7 million tons of methane is released annually from the East Siberian Arctic Shelf — a small percentage of total greenhouse gas emissions, but potentially enough to account for recent increases in atmospheric methane levels.
It's correct that an extra methane molecule is something like 25 times more influential than an extra CO2 molecule, although that ratio is primarily determined by the background atmospheric concentration of either gas, and GWP typically assumes that forcing is linear in emission pulse, which is not valid for very large perturbations.
The most significant is that the UT Austin study looked only at the production stage of natural gas, while the Harvard study used atmospheric measurements to estimate methane emissions from all sources.
The identification of other, sometimes more powerful, greenhouse gases such as methane, the contributions to atmospheric carbon dioxide from other human activities such as deforestation and cement manufacture, better understanding of the temperature - changing properties of atmospheric pollution such as sulphur emissions, aerosols and their importance in the post-1940s northern hemisphere cooling: the knowledge - base was increasing year by year.
Once permafrost starts melting, there are feedbacks from changes in albedo, methane emissions, the thermal properties of surface water, and increases in atmospheric water vapor.
a b c d e f g h i j k l m n o p q r s t u v w x y z