Sentences with phrase «aerosol changes on»

Not exact matches

And by carefully measuring and modeling the resulting changes in atmospheric composition, scientists could improve their estimate of how sensitive Earth's climate is to CO2, said lead author Joyce Penner, a professor of atmospheric science at the University of Michigan whose work focuses on improving global climate models and their ability to model the interplay between clouds and aerosol particles.

The computer model determines how the average surface temperature responds to changing natural factors, such as volcanoes and the sun, and human factors — greenhouse gases, aerosol pollutants, and so on.

The theory of dangerous climate change is based not just on carbon dioxide warming but on positive and negative feedback effects from water vapor and phenomena such as clouds and airborne aerosols from coal burning.

In the tug of war, aerosols don't necessarily counter the impacts of climate change on sea ice (or the planet as a whole for that matter).

But there are a lot of lingering questions, says Stevens, who also was a lead author on the «Clouds and Aerosols» chapter of the Intergovernmental Panel on Climate Change's Fifth Assessment Report.

Two important aerosol species, sulfate and organic particles, have large natural biogenic sources that depend in a highly complex fashion on environmental and ecological parameters and therefore are prone to influence by global change.

Aerosols in the tropopause also complicate climate projections; they are not taken into account in the latest assessment released in 2013 by the Intergovernmental Panel on Climate Change, says Yu Gu, a climate scientist at the University of California, Los Angeles.

Indeed the estimate of aerosol forcing used in the calculation of transient climate response (TCR) in the paper does not come directly from climate models, but instead incorporates an adjustment to those models so that the forcing better matches the assessed estimates from the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC).

The particle soot absorption photometer collects aerosol particles on a substrate and measures the change in light transmission relative to a reference filter.

A multidisciplinary team led by Pacific Northwest National Laboratory's Dr. Chuck Long found that, at least in the continental United States, changes in clouds and cloudiness have a greater influence on brightening than any decrease in aerosol amounts alone.

I guess I am surprised that with better understanding of the importance of water vapor feedback, sulfate aerosols, black carbon aerosols, more rapid than expected declines in sea ice and attendant decreases in albedo, effects of the deposition of soot and dust on snow and ice decreasing albedo, and a recognition of the importance of GHGs that were probably not considered 30 years ago, that the sensitivity has changed so little over time.

Sally, who was nominated by Dr. Beat Schmid, Associate Director, Atmospheric Sciences and Global Change Division, was honored for her exceptional contribution in the field of atmospheric science, particularly in her efforts to improve understanding of the radiative effect of clouds and aerosols on the Earth's atmosphere and their representation in climate models.

Results: Predicting future climate change hangs on understanding aerosols, considered the fine details in the atmosphere.

These programs focus on climate, aerosol and cloud physics; global and regional scale modeling; integrated assessment of global change; and complex regional meteorology and chemistry.

And finally, current theories based on greenhouse gas increases, changes in solar, volcanic, ozone, land use and aerosol forcing do a pretty good job of explaining the temperature changes over the 20th Century.

The Intergovernmental Panel on Climate Change (IPCC) considers that the increase in aerosols and clouds since pre-industrial times represents one of the largest sources of uncertainty in climate change5.

In addition, researchers calculated the changes in the shortwave and longwave and net radiation between the pre-industrial simulation and the present - day simulations to estimate the radiative forcing resulting from the aerosol effects on cirrus clouds.

These changes made China a unique region to investigate the impact of aerosols on regional climate and the hydrological cycle.

Stratospheric heating by potential geoengineering aerosols Geoengineering aerosols change stratospheric radiative heating rates Heating rates depend on aerosol species and size

The top priorities should be reducing uncertainties in climate sensitivity, getting a better understanding of the effect of climate change on atmospheric circulation (critical for understanding of regional climate change, changes in extremes) and reducing uncertainties in radiative forcing — particularly those associated with aerosols.

While not authoritative, this USGS page on volcanoes and climate change discusses sulfate aerosols and CO2 and also links to the Gerlach EOS paper.

Forster and Gregory (2006) estimate ECS based on radiation budget data from the ERBE combined with surface temperature observations based on a regression approach, using the observation that there was little change in aerosol forcing over that time.

For the sake of interpreting on - going and future climate change it is highly desirable to obtain precise monitoring of the global aerosol forcing [73].

I guess I am surprised that with better understanding of the importance of water vapor feedback, sulfate aerosols, black carbon aerosols, more rapid than expected declines in sea ice and attendant decreases in albedo, effects of the deposition of soot and dust on snow and ice decreasing albedo, and a recognition of the importance of GHGs that were probably not considered 30 years ago, that the sensitivity has changed so little over time.

If «The most extreme scenario postulated in TAR» is almost solely dependent on GHG emissions, why would the introduction of aerosol effects not change the results?

Also, due to the multiplicity of anthropogenic and natural effects on the climate over this time (i.e. aerosols, land - use change, greenhouse gases, ozone changes, solar, volcanic etc.) it is difficult to accurately define the forcings.

Among those choices as well as the rest including reducing fossil fuel combustion, deforestation, etc., one would want to find the cheapest / easiest, but also the most effective (the firmest grasp on that knob) and the safest / least negative side - effects - such as those you'd get from non - spatially / temporally - discrimating solar shades / cooling aerosols (precipitation changes, and?

On the one hand it repeats the oft argued claim that the cooling after 1940 was largely due to sulfate aerosols produced by «industrial activities,» but on the other hand, she is honest enough to admit that «the situation is complicated» by factors rarely addressed by cli - change advocateOn the one hand it repeats the oft argued claim that the cooling after 1940 was largely due to sulfate aerosols produced by «industrial activities,» but on the other hand, she is honest enough to admit that «the situation is complicated» by factors rarely addressed by cli - change advocateon the other hand, she is honest enough to admit that «the situation is complicated» by factors rarely addressed by cli - change advocates:

It hardly takes imagination to posit that while initial aerosol dimming might depress temperatures, the aerosols and atmosphere might react in ways that change heat balance in other directions as they disperse, through stratospheric chemistry, and the fact that, unsurprisingly, there is a difference in aerosol behaviour depending on day vs night (you can't reduce the sunlight that reaches the south pole on June 23rd....).

But that was within the constraints of the model (no change in aerosol influence, lack of solar stratospheric influences, no influence of solar on cloud cover...).

It is conceivable that aerosol effects (which includes «smoke») could also affect the lapse rate, but the aerosols tend to warm where they are located and depending on the composition, cool below — this gives an impact that — if it was a large factor in the tropical mean — would produce changes even larger than predicted from the moist adiabatic theory.

First, for changing just CO2 forcing (or CH4, etc, or for a non-GHE forcing, such as a change in incident solar radiation, volcanic aerosols, etc.), there will be other GHE radiative «forcings» (feedbacks, though in the context of measuring their radiative effect, they can be described as having radiative forcings of x W / m2 per change in surface T), such as water vapor feedback, LW cloud feedback, and also, because GHE depends on the vertical temperature distribution, the lapse rate feedback (this generally refers to the tropospheric lapse rate, though changes in the position of the tropopause and changes in the stratospheric temperature could also be considered lapse - rate feedbacks for forcing at TOA; forcing at the tropopause with stratospheric adjustment takes some of that into account; sensitivity to forcing at the tropopause with stratospheric adjustment will generally be different from sensitivity to forcing without stratospheric adjustment and both will generally be different from forcing at TOA before stratospheric adjustment; forcing at TOA after stratospehric adjustment is identical to forcing at the tropopause after stratospheric adjustment).

So, I know that CO2 fertilization has been considered in terms of its effects on 20th century trees used in reconstructions — has there been considerations of changes in diffuse light due to aerosol emissions?

These forcings are spatially heterogeneous and include the effect of aerosols on clouds and associated precipitation [e.g., Rosenfeld et al., 2008], the influence of aerosol deposition (e.g., black carbon (soot)[Flanner et al. 2007] and reactive nitrogen [Galloway et al., 2004]-RRB-, and the role of changes in land use / land cover [e.g., Takata et al., 2009].

In addition there is still clear evidence in my view for aerosols having played a significant role in holding back that warming, which acts on top of the effects of internal variability which play an important role in fluctuations about the forced changes.

The continent's policies most likely have the biggest effect on aerosol - related climate change.

Better understanding of the effect of aerosols on Earth's climate in the past can help climate scientist make better predictions of climate change trends in the future, the researchers said.

In models that include indirect effects, different treatments of the indirect effect are used, including changing the albedo of clouds according to an off - line calculation (e.g., Tett et al., 2002) and a fully interactive treatment of the effects of aerosols on clouds (e.g., Stott et al., 2006b).

This is the portion of temperature change that is imposed on the ocean - atmosphere - land system from the outside and it includes contributions from anthropogenic increases in greenhouse gasses, aerosols, and land - use change as well as changes in solar radiation and volcanic aerosols.

Our model suggests that the effect of changes in cosmic ray intensity on CCN is small and unlikely to be comparable to the large variations in natural primary aerosol emissions.

On the question of hurricanes, the theoretical arguments that more energy and water vapor in the atmosphere should lead to stronger storms are really sound (after all, storm intensity increases going from pole toward equator), but determining precisely how human influences (so including GHGs [greenhouse gases] and aerosols, and land cover change) should be changing hurricanes in a system where there are natural external (solar and volcanoes) and internal (e.g., ENSO, NAO [El Nino - Southern Oscillation, North Atlantic Oscillation]-RRB- influences is quite problematic — our climate models are just not good enough yet to carry out the types of sensitivity tests that have been done using limited area hurricane models run for relatively short times.

Based on evidence from Earth's history, we suggest here that the relevant form of climate sensitivity in the Anthropocene (e.g. from which to base future greenhouse gas (GHG) stabilization targets) is the Earth system sensitivity including fast feedbacks from changes in water vapour, natural aerosols, clouds and sea ice, slower surface albedo feedbacks from changes in continental ice sheets and vegetation, and climate — GHG feedbacks from changes in natural (land and ocean) carbon sinks.

Future emails will include: the difference between contrails / vapour trails and Stratospheric Aerosol Injection observations on covert atmospheric spraying (their tactics have changed in the last few weeks — this has been noticed globally) who is controlling the spraying — who are «they» much of the northern hemisphere is burning — California, Canada, Siberia (2,000 mile smoke clouds), Sweden etc..

The models used the Intergovernmental Panel on Climate Change's «A1B» mid-range projected emission scenarios for ozone and aerosol precursors, independently calculated the resulting composition change, and then performed transient simulations to 2050 examining the response to projected changes in the short - lived species and to changes in both long - lived and short - lived species togChange's «A1B» mid-range projected emission scenarios for ozone and aerosol precursors, independently calculated the resulting composition change, and then performed transient simulations to 2050 examining the response to projected changes in the short - lived species and to changes in both long - lived and short - lived species togchange, and then performed transient simulations to 2050 examining the response to projected changes in the short - lived species and to changes in both long - lived and short - lived species together.

Contribution from working group I to the fifth assessment report by IPCC TS.5.4.1 Projected Near - term Changes in Climate Projections of near - term climate show small sensitivity to Green House Gas scenarios compared to model spread, but substantial sensitivity to uncertainties in aerosol emissions, especially on regional scales and for hydrological cycle variables.

This relationship between cumulative emissions and warming is not perfect, as it will change based on what happens to non-CO2 greenhouse gases, such as methane and nitrous oxide, as well as how quickly climate - cooling aerosols are reduced.

Additionally, changes in anthropogenic sulfate aerosol forcing have been proposed as the dominant cause of the AMV and the historical multidecadal variations in Atlantic tropical storm frequency, based on some model simulations including aerosol indirect effects.

When Gort first visited in 1951, it spent little effort on climate change issues, focusing on other aspects of our planet instead: Gort returned in 2012 to answer puny human climatologist questions about whether climate change caused particular weather phenomena by making an obvious point: rather than struggle with theoretical analysis, you can simply use your Climate Changeometer to remove all the excess greenhouse gases and aerosols above natural levels and then measure the outcome.

Urban heat island - The relative warmth of a city compared with surrounding rural areas, associated with changes in runoff, the concrete jungle effects on heat retention, changes in surface albedo, changes in pollution and aerosols, and so on.

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..