Sentences with phrase «anthropogenic aerosol emissions»

The sections below give a systematic overview of the major natural aerosol sources and their relations to climate parameters while anthropogenic aerosol emissions and combined aerosols are the subject of Chapter 2.

The current approach that is generally pursued assumes essentially that past climate variability is indistinguishable from a stochastic red - noise process... Given such a null hypothesis, the official consensus of IPCC (1995) tilts towards a global warming effect of recent trace - gas emissions, which exceeds the cooling effect of anthropogenic aerosol emissions.»

Karsten / Mikel, As far as the mid-century northern hemisphere cooling goes, attributed usually to anthropogenic aerosol emissions as you are saying, I wonder what became of the highly publicised Thompson et al. 2010 Nature article - Thompson, D. W. J., Wallace, J. M., Kennedy, J. J. & Jones, P. D., (2010): «An abrupt drop in Northern Hemisphere sea surface temperature around 1970», Nature 467, 444 - 447.

This is problematic for the previous estimate because anthropogenic aerosol emissions existed prior to 1750.

These scenarios presume that there are no major volcanic eruptions and that anthropogenic aerosol emissions are rapidly reduced during the near term.

We have seen a combination of the solar minimum, anthropogenic aerosol emissions and back - to - back La Niñas.»

Here we show the climate impacts from removing present - day anthropogenic aerosol emissions and compare them to the impacts from moderate GHG - dominated global warming.

«Our findings,» write the authors, «suggest that anthropogenic aerosol emissions influenced a range of societally important historical climate events such as peaks in hurricane activity and Sahel drought.»

Not exact matches

Overall, the new measures would lower global anthropogenic emissions of methane by 50 % and of black carbon aerosols, also known as soot, by 80 %.

The study also showed that the effect was much larger on a regional scale, counteracting possibly up to 30 % of warming in more rural, forested areas where anthropogenic emissions of aerosols were much lower in comparison to the natural aerosols.

Aerosols are solid or liquid particles suspended in the atmosphere, consisting of (in rough order of abundance): sea salt, mineral dust, inorganic salts such as ammonium sulfate (which has natural as well as anthropogenic sources from e.g. coal burning), and carbonaceous aerosol such as soot, plant emissions, and incompletely combusted fossil fuel.

Historical (1850 - 2000) gridded anthropogenic and biomass burning emissions of reactive gases and aerosols: Methodology and application.

c) anthropogenic aerosols — mainly sulfate and nitrate (from emissions of SO2 and NOx / NH3) have a strong direct effect and undoubted liquid cloud nucleation impacts (the indirect effects).

Has anyone modeled and published the effects of anthropogenic Chinese / Indian aerosol emissions on monsoonal / SE Asian climate?

The declining signal over India shown by the GPCP decadal mode is broadly consistent with gauge measurements since the 1950s — that several research groups including my own are trying to understand, perhaps relating to emissions of anthropogenic aerosol — although there are discrepancies between these gauge - based data sets themselves (see our recent review in Nature Climate Change, for example).

Such is the case for the explanation — popular with the press when it was first proposed — that an increase in aerosol emissions, particularly from China, was acting to help offset the warming influence of anthropogenic carbon dioxide emissions.

Stratospheric ozone in models is erroneously being driven CFC emissions rather than ozone destroying sulphuric acid aerosols for stratospheric volcanic eruptions, and thus also providing a spurious anthropogenic post-2000 forcing.

So now we have a new (anthropogenic, of course) explanation: «unexpected» Chinese aerosol emissions.

The future concentrations of LLGHGs and the anthropogenic emissions of sulphur dioxide (SO2), a chemical precursor of sulphate aerosol, are obtained from several scenarios considered representative of low, medium and high emission trajectories.

Scientists found that emissions of tiny air particles from human - made sources — known as anthropogenic aerosols — were the cause.

Effects of anthropogenic emissions on aerosol formation from isoprene and monoterpenes in the southeastern United States

The most important factors are anthropogenic emissions of greenhouse gases, land use changes and emissions of aerosols.

If there were a deficit of CCN that is augmented by anthropogenic emissions of aerosols — then this would be a positive feedback rather than a negative one.

It depends on the relative quantities of anthropogenic or natural aerosol emissions — 25 - 50 % in some estimates.

Primary emphasis is placed on investigation of climate sensitivity — globally and regionally, including the climate system's response to diverse forcings such as solar variability, volcanoes, anthropogenic and natural emissions of greenhouse gases and aerosols, paleo - climate changes, etc..

As an example, anthropogenic SO2 aerosol emissions totaled 131 Megatonnes in 1975, and by 2011 they had dropped to 101 Megatonnes, a drop of 30 Megatonnes..

First, the complicated models that develop emissions scenarios don't seem to be necessary for forcing the climate models; simply specifying a value of CO2 concentration (with the other greenhouse gases and anthropogenic aerosol) at 2100 along with a simple time trajectory is sufficient to force the climate model.

All of the warming since 1972 has been due to the removal of strongly dimming anthropogenic SO2 aerosol emissions from the atmosphere (more than 30 Megatonnes)

It is self evident that anthropogenic greenhouse gas emissions, aerosols, and land use changes are candidates for this type of application.

Surely, it does not all hang on the fact that Europle cleaned up its aerosol emissions and therefore anthropogenic warming very likely slightly or moderately outedges natural warming compared with 200 years ago, and if Europe had not cleaned up its act a little and temperatures were 0.2 C lower today, global warming would be a non issue.

«since the mid 1980s a significant increase in visibility has been noted in western Europe (e.g. Doyle and Dorling, 2002), and there are strong indications that a reduction in aerosol load from anthropogenic emissions (in other words, air pollution) has been the dominant contributor to this effect, which is also referred to as «brightening».»

Real Climate defines «aerosols» as ``... solid or liquid particles suspended in the atmosphere, consisting of (in rough order of abundance): sea salt, mineral dust, inorganic salts such as ammonium sulfate (which has natural as well as anthropogenic sources from e.g. coal burning), and carbonaceous aerosol such as soot, plant emissions, and incompletely combusted fossil fuel.»

• More than 100 % (i.e. GHG warming has been partly offset by aerosol cooling) • Between 76 % and 100 % • Between 51 % and 76 % • Between 26 % and 50 % • Between 0 and 25 % • Less than 0 % (i.e. anthropogenic GHG emissions have caused cooling) • There has been no warming • Unknown due to lack of knowledge • I do not know • Other (please specify)

Aerosol concentrations eventually decrease in all RCPs, following the strong decrease in emissions, especially those of anthropogenic SO2.

The 2007 report focussed on greenhouse gasses, he said, whereas the 2013 report included all «anthropogenic forcings», including «the cooling effect from human aerosol emissions».

In order to better understand the causes of the Arctic's changing climate, the authors used observational data and nine CMIP5 global climate models to tease apart the effects of anthropogenic greenhouse gas emissions, natural forcings and other anthropogenic forcings (aerosols, ozone and land use changes).

The first sentence of the opening paragraph reads, «The time history of observed twentieth - century global - mean surface temperature reflects the combined influences of naturally occurring climate variations and anthropogenic emissions of greenhouse gases and sulfate aerosols.»

To slow the rate of anthropogenic - induced climate change in the 21st century and to minimize its eventual magnitude, societies will need to manage the climate forcing factors that are directly influenced by human activities, in particular greenhouse gas and aerosol emissions.

I'm only saying this to note I know the anthropogenic aerosols from this period can't be directly compared to the emission rate per fossil fuel input as later in the 20th century.

«This study has demonstrated for the first time, using in - situ PM measurements, that reducing aerosol pollution is driving the Insolation Brightening phenomenon and that the trends in aerosol pollution, particularly for sulphate aerosol, is directly linked to anthropogenic emissions.

Furthermore, estimating the direct and indirect aerosol effects (29) through 2008 as a residual from the Earth's energy balance (as was done for 1954 — 2000) would generate results that either support or contradict the increased importance of anthropogenic sulfur emissions discussed above.

Hmmm... don't suppose it occurred to anyone to check the amount of anthropogenic aerosols that were emitted during this time frame 1940 - 1970, or the fact that aerosols have an immediate cooling effect on troposphere temperatures that can mask the underlying warming caused by the CO2 emissions that also accompany the aerosols.

Anthropogenic emissions include many types of GHG's as well as particulates such as black carbon and sulfate aerosols, each of which has a different effect on the atmosphere, and a different atmospheric lifetime.

The study also showed that the effect was much larger on a regional scale, counteracting possibly up to 30 % of warming in more rural, forested areas where anthropogenic emissions of aerosols were much lower in comparison to the natural aerosols.

The climate feedbacks involved with these changes, which are key in understanding the climate system as a whole, include: + the importance of aerosol absorption on climate + the impact of aerosol deposition which affects biology and, hence, emissions of aerosols and aerosol precursors via organic nitrogen, organic phosphorus and iron fertilization + the importance of land use and land use changes on natural and anthropogenic aerosol sources + the SOA sources and impact on climate, with special attention on the impact human activities have on natural SOA formation In order to quantitatively answer such questions I perform simulations of the past, present and future atmospheres, and make comparisons with measurements and remote sensing data, all of which help understand, evaluate and improve the model's parameterizations and performance, and our understanding of the Earth system.

Google «historic SO2 emissions» (an important precursor to anthropogenic aerosol) and the first document to come up is this one.

Finally, the last argument that climate hawks would employ is that anthropogenic effects, specifically emission of SO2 aerosols and carbon black, have been reflecting sunlight and offsetting the global warming effect.