Sentences with phrase «natural atmospheric emissions»

Not exact matches

Non-polar glacial ice holds a wealth of information about past changes in climate, the environment and especially atmospheric composition, such as variations in temperature, atmospheric concentrations of greenhouse gases and emissions of natural aerosols or human - made pollutants... The glaciers therefore hold the memory of former climates and help to predict future environmental changes.

«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.

Together, they confirm estimates from atmospheric chemists that natural tropical forests absorb about a fifth of our carbon 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.

In a printed statement, Pieter Tans of the agency's Earth System Research Laboratory in Boulder, Colo., said the only way to stop growth in the atmospheric concentration of the gases is to reduce emissions enough that natural processes can keep pace.

Combustion of coal, oil, and natural gas, and to a lesser extent deforestation, land - cover change, and emissions of halocarbons and other greenhouse gases, are rapidly increasing the atmospheric concentrations of climate - warming gases.

It is possible that the observed annual increases in atmospheric CO2 are almost entirely natural and that humanmade emissions are practically irrelevant.

Therefore, it is possible that all of the rise in atmospheric CO2 concentration and all of the change to the 13C: 12C atmospheric isotope change were caused by the anthropogenic emission that induced the unknown, natural (i.e. non-anthropogenic) effect that caused the observed change to the 12C: 13C isotope ratio of atmospheric CO2.

Simply, it is possible that none of the rise in atmospheric CO2 concentration and none of the change to the 13C: 12C atmospheric isotope change were caused by anthropogenic emission but were due to the unknown, natural (i.e. non-anthropogenic) effect that caused most of the change to the 12C: 13C isotope ratio of atmospheric CO2.

Jack Greer says: February 3, 2011 at 5:43 pm quote The current scientific understanding of Earth's carbon cycles that, at this time, natural carbon emission sources weighed against natural carbon sinks should result in a net reduction in atmospheric CO2 levels.

There is no way you can work out accurately natural emissions of CO2 and natural sinks from just knowing ACO2 emissions and the atmospheric increase.

Even in the unlikely event that we were to stop all emissions in the near future, this permafrost climate feedback would likely continue as a self - sustaining process, cancelling out any future natural draw - down in atmospheric carbon dioxide levels by the oceans or vegetation.

I think that even laymen can be made understand the natural law, according to which both all the CO2 sources and all the CO2 sinks together control the CO2 content in the atmosphere, and that the share of the anthropogenic CO2 emissions in the atmospheric CO2 content depends on how the quantity of anthropogenic CO2 emissions is in the proportion to the total CO2 emissions.

(atmospheric change — human emissions — natural sources = natural sinks)

The current scientific understanding of Earth's carbon cycles that, at this time, natural carbon emission sources weighed against natural carbon sinks should result in a net reduction in atmospheric CO2 levels.

Indeed the natural flows may well be as you describe (or one of the options you describe), and they may well be of interest, but one thing is certain, when atmospheric concs are rising, and rising at a rate that is less than ACO2 emissions, then without the ACO2 they would not be rising.

It seems to me that intuitively, they could not accept the hypothesis that human emissions may not be responsible for an apparent increase in atmospheric CO2, no matter how good the correlation to natural sources might be.

According to the IPCC's figures (as presented in 2007 AR4) anthropogenic emissions amount to 29gtons / year while natural CO2 emissions amount to 771gtons / year and the atmospheric mass currently stands at about 3000gtons.

I have no doubt that it is a greenhouse gas but, if the atmospheric content is a function of the integral of global temperature and unrelated to anthropogenic emissions, It seems these emissions are too insignificant in relation to natural CO2 variations to have any measurable effect.

The statement that only 55 % of human CO2 emissions have been removed by the biosphere / biosphere is something you'll have to prove, which is hard because as far as I'm aware human CO2 does not posses an isotopic signature that can be easily differentiated from natural sources — the arguments you often hear on Skeptical Science are measurements in changes of the C12 / C13 / C14 atmospheric mass, not individual CO2 molecules, which can be misleading.

36 Cut fossil fuel use (especially coal) Solutions Global Warming Prevention Cleanup Cut fossil fuel use (especially coal) Remove CO2 from smoke stack and vehicle emissions Shift from coal to natural gas Store (sequester) CO2 by planting trees Improve energy efficiency Sequester CO2 deep underground Shift to renewable energy resources Sequester CO2 in soil by using no - till cultivation and taking cropland out of production Transfer energy efficiency and renewable energy technologies to developing countries Reduce deforestation Figure 20.14 Solutions: methods for slowing atmospheric warming during this century.

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.

In the global aggregate, 21 gigatons of carbon dioxide emissions a year, more or less, is the sustainable global limit for natural cycles to keep atmospheric carbon dioxide levels level.

Simulations with natural forcings only suggest that atmospheric CO2 would have remained around the preindustrial concentration of 280 ppm without anthropogenic emissions.

Originally denoted «climate change skeptics» or «anthropogenic (human - induced) global warming skeptics», the term referred to those who are as yet unconvinced by evidence that emissions of man - made CO2 significantly enhance the natural atmospheric greenhouse effect.

Climate Change Deniers, also known as Anthropogenic Global Warming (AGW) Deniers, refers to individuals or groups who disagree with the global scientific consensus that emissions of man - made CO2 significantly enhance the natural atmospheric greenhouse effect.

Will the greenhouse gas emissions from expanded natural gas push the global concentrations of atmospheric GHGs beyond what is consistent with safe climate stabilization?

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».

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 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.

Given that this is a far from equilibrium system, it is far from clear that our modest human emissions and sinks (compared to the far greater natural emissions and sinks) are in fact causing the atmospheric increase.

Start with this nonsense «it is far from clear that our modest human emissions and sinks (compared to the far greater natural emissions and sinks) are in fact causing the atmospheric increase.»

David «Given that this is a far from equilibrium system, it is far from clear that our modest human emissions and sinks (compared to the far greater natural emissions and sinks) are in fact causing the atmospheric increase.

Though sources, sinks, and atmospheric burden are now well known, apportionment between the myriad sources and sinks, and forecasting natural emissions, remains a challenge.

We can not be emitting more CO2 than is staying in the atmosphere, have nature acting on the balance as a sink, and magically have the increase in atmospheric CO2 be attributable to natural rather than anthropogenic emissions.

Recent research on the mitigation potential of conservation, restoration, and improved land management demonstrates that natural solutions can reduce emissions and remove atmospheric CO2 while safeguarding food security and biodiversity.

Long - term Cenozoic temperature trends, the warming up to about 50 Myr before present (BP) and subsequent long - term cooling, are likely to be, at least in large part, a result of the changing natural source of atmospheric CO2, which is volcanic emissions that occur mainly at continental margins due to plate tectonics (popularly «continental drift»); tectonic activity also affects the weathering sink for CO2 by exposing fresh rock.

One can make this quite a bit more complicated, because as you correctly note the magnitude of the gross fluxes (e.g., natural sinks) isn't independent of the atmospheric concentration, so one can't just say that if we removed all human emissions the net natural flux would still be negative and atmospheric CO2 would be decreasing.

The possibility that natural variability explains the century - scale observed rise in atmospheric CO2 can easily be dismissed based on simple accounting (anthropogenic emissions are larger than the rise itself, and thus account for over 100 % of the observed rise).

To simplify the idea — if 95 % of atmospheric CO2 is natural but we do not know how much overall the natural emissions amounts change over time, but we do know they change, it is easy to see that a 10 % change in natural emissions would have potentially great change to total CO2.

If the oceans were the source of the recent atmospheric CO2 increase it would require some natural sink to have increased in recent years specifically to hide the human emission.

The strongest evidence yet that the rise in atmospheric CO2 emissions continues to outstrip the ability of the world's natural «sinks» to absorb carbon is published this week in the journal Nature Geoscience.

«We do know for certain that the natural environment is a net carbon sink, becuase the annual rise in atmospheric CO2 is always less than anthropogenic emissions is useless information.

It also alters the atmospheric circulation, which feeds back to dust emission from natural sources (see Section 7.5.4).

The natural environment takes up more than it emits, and it is the difference between emissions and uptake that governs the rise in atmospheric CO2.

Professor Murry Salby's lecture carries this two steps further in a) postulating an alternate hypothesis for natural changes in atmospheric CO2 levels and b) effectively falsifying the claim that C12 / C13 isotope measurements provide «smoking gun proof» for the postulation that increased CO2 levels are being caused by human emissions.

Professor Salby shows how natural factors correlate much more closely with the change in atmospheric CO2 than human emissions and effectively shoots down the C13 «smoking gun» postulation cited as «proof» that human emissions are the cause.