Sentences with phrase «effect of the aerosol increase»

If the direct effect of the aerosol increase is considered, surface temperatures will not get as warm because the aerosols reflect solar radiation.

Not exact matches

A 2013 computer simulation of this process found increased aerosols alone did result in more lightning due to ice crystal collisions, although at very large aerosol volumes the effect was muted.

Possible reasons include increased oceanic circulation leading to increased subduction of heat into the ocean, higher than normal levels of stratospheric aerosols due to volcanoes during the past decade, incorrect ozone levels used as input to the models, lower than expected solar output during the last few years, or poorly modeled cloud feedback effects.

The potential risks around sulfate aerosol solar geoengineering include alteration of regional precipitation patterns, its effects on human health, and the potential damage to Earth's ozone layer by increased stratospheric sulfate particles.

When Aldrin adds a fixed cloud lifetime effect of -0.25 W / m ^ 2 forcing on top of his variable parameter direct and (1st) indirect aerosol forcing, the mode of the sensitivity PDF increases from 1.6 to 1.8.

For example, they predicted the expansion of the Hadley cells, the poleward movement of storm tracks, the rising of the tropopause, the rising of the effective radiating altitude, the circulation of aerosols in the atmosphere, the modelling of the transmission of radiation through the atmosphere, the clear sky super greenhouse effect that results from increased water vapor in the tropics, the near constancy of relative humidity, and polar amplification, the cooling of the stratosphere while the troposphere warmed.

From the Physical Science Basis: «Shindell et al. (2009) estimated the impact of reactive species emissions on both gaseous and aerosol forcing species and found that ozone precursors, including methane, had an additional substantial climate effect because they increased or decreased the rate of oxidation of SO2 to sulphate aerosol.

Let me try to be more explicit: if you want to assume (or, if you prefer, conclude) that aerosols produced by the increased burning of fossil fuels after WWII had a cooling effect that essentially cancelled out the warming that would be expected as a result of the release of CO2 produced by that burning, then it's only logical to conclude that there exists a certain ratio between the warming and cooling effects produced by that same burning.

There are an ever increasing number of these «indirect effects», but the two most discussed are the aerosol / cloud opacity interaction (more aerosols provide more sites for water to condense in clouds, thus cloud droplets are smaller and clouds become more opaque), and the cloud lifetime effect (smaller droplets make it more difficult to make drops big enough to rain, and so clouds live longer).

The fraction of the light that scatters back out to space is responsible for the increased albedo and the cooling effect from sulfate aerosols.

However, simulations using the relatively straightforward «direct effect» of aerosols (the increase in albedo of the planet due to the particle brightness) do not match the inferred changes.

Moreover, the heat content of the oceans increased more in the NH than in the SH (again, if corrected for area), while 90 % of the aerosols are emitted and have their effect in the NH.

In this case, the vast preponderance of evidence and theory (such as long established basic physics) is on the side of AGW, so there would have to be a serious paradigm shift based on some new physics, a cooling trend (with increasing GHG levels and decreasing aerosol effect), and that they had failed to detect the extreme increase in solar irradiance to dislodge AGW theory.

In other words, if we are after a cause (or causes) for the temperature increase during the period in question, the presence or absence of aerosols from volcanic eruptions is beside the point, because they can not explain any increase in temperatures that occurred prior to any cooling effect they might have had.

SW fails to mention effects that may counter-act warming trends, such as irrigation, better shielding of the thermometers, and increased aerosol loadings, in addition to forgetting the fact that forests were cut down on a large scale in both Europe and North America in the earlier centuries.

Considering also that Northern Hemispheric cooling in 1940 — 70 is attributable to the «global dimming» effect of increasing sulfate aerosols, the sulfate cooling effect is, again, felt more strongly in Greenland, and indirectly via altered atmospheric dynamics not via local radiation budget modification.

Increased numbers of aerosols provide additional locations for droplet nucleation and, all else being equal, result in clouds with more and smaller droplets hence being more reflective to solar radiation (a cooling effect).

Basic physical science considerations, exploratory climate modeling, and the impacts of volcanic aerosols on climate all suggest that SWCE could partially compensate for some effects — particularly net global warming — of increased atmospheric CO2.

Barrett also predicted that this increase in CO2 «should increase the temperature by 0.3 °C; this trend might be detectable by careful analysis unless it is offset by other effects, such as those of aerosols».

As you say, implicit in this is that «the aerosol forcing is strongly negative introduces a fudge - factor that has the effect of artificially increasing climate sensitivity».

An increased greenhouse effect due to humidity, CO2, aerosols or clouds is expected to produce a relative increase of the minima with respect to the maxima and a decrease of the diurnal range.

However, I am not a «warmista» by any means — we do not know how to properly quantify the albedo of aerosols, including clouds, with their consequent negative feedback effects in any of the climate sensitivity models as yet — and all models in the ensemble used by the «warmistas» are indicating the sensitivities (to atmospheric CO2 increase) are too high, by factors ranging from 2 to 4: which could indicate that climate sensitivity to a doubling of current CO2 concentrations will be of the order of 1 degree C or less outside the equatorial regions (none or very little in the equatorial regions)- i.e. an outcome which will likely be beneficial to all of us.

Richard Courtney rightly reminds us that the models» assumption that the aerosol forcing is strongly negative introduces a fudge - factor that has the effect of artificially increasing climate sensitivity.

A few locations over land exhibit weak cooling over this time, perhaps a signature of the effects of increasing aerosol particles due to combustion and biomass burning, or a result of changes in land use.

The prominent upward trend in the GM precipitation occurring in the last century and the notable strengthening of the global monsoon in the last 30 yr (1961 — 90) appear unprecedented and are due possibly in part to the increase of atmospheric carbon dioxide concentration, though the authors» simulations of the effects from recent warming may be overestimated without considering the negative feedbacks from aerosols.

Note that while the BEST approach is based on correlations, they are correlations of variables with known causal relationships (i.e. an increased greenhouse effect is known to cause global warming), although they do not appear to have considered some important influences like human aerosol emissions or the El Niño Southern Oscillation.

In particular, increases in the number of small particles (called aerosols) in the atmosphere regionally offset and mask the greenhouse effect, and stratospheric ozone depletion contributes to cooling of the upper troposphere and stratosphere.fr2], fr3]

Figure 9.5 shows that simulations that incorporate anthropogenic forcings, including increasing greenhouse gas concentrations and the effects of aerosols, and that also incorporate natural external forcings provide a consistent explanation of the observed temperature record, whereas simulations that include only natural forcings do not simulate the warming observed over the last three decades.

Let's also say the contribution from aerosols is zero (it should be some small negative number since they were increasing, and the net effect of aerosols is cooling, but we'll ignore for this analysis).

Model simulations of the Asian monsoon project that the sulphate aerosols» direct effect reduces the magnitude of precipitation change compared with the case of only greenhouse gas increases (Emori et al., 1999; Roeckner et al., 1999; Lal and Singh, 2001).

[note] In this context it intrigues me that those who advocate for stratospheric aerosol injection (SAI) tend to ignore the possibility that the possible termination effect would increase net risk from greenhouse gas emissions, and the deployment of SAI should therefore (in risk adjustment terms) justify accelerated mitigation rather than reduced mitigation.

However, the relative cooling effect of sulphate aerosols is dominated by the effects of increasing greenhouse gases by the end of the 21st century in the SRES marker scenarios (Figure 10.26), leading to the increased monsoon precipitation at the end of the 21st century in these scenarios (see Section 10.3.2.3).

However, if one converts the total effects of all greenhouse gases, aerosols, etc. into an equivalent increase in CO2 concentration (by reference to their effective radiative forcing RF, that from a doubling of CO2 being F2xCO2), then what you suggest would be pretty much in line with the generic definition of TCR in Section 10.8.1 of AR5 WGI:

The situation we have here is that the cooling effect of man - made aerosols has declined appreciably [since 1951] as CO2 emissions and other GHGs have increased, so we would expect even greater warming, which hasn't happened.

A) a better temperature record (C&W or berkeley) both of which will increase the numerator (that thing on the top) B) a better OHC record (see the recent paper on sea level which will effect their estimates of OHC (the denominator thing) C) revised forcing due to aerosols from small volcanos.

The indirect aerosol effect may include increased cloud brightness, as aerosols lead to a larger number of smaller cloud droplets (the so - called Twomey effect), and increased cloud cover, as smaller droplets inhibit rainfall and increase cloud lifetime.

For aerosols, however, the net effect of increase in density is to reduce the surface temperature of Earth.

So far, the initial effect is still relatively small for two reasons: (i) part of that effect has been canceled temporarily by increases in sulfate aerosol, and (ii) the warming has been delayed because it takes a long time for the vast mass of the ocean to heat up.

The latter effect acts to reduce CO2 sensitivity by increasing the aerosol - sensitive SW tau, increasing both cloud density and cover, decreasing upper tropospheric specific humidity and INCREASING SW albedo and will increasingly do so as the atmospheric level of increasing the aerosol - sensitive SW tau, increasing both cloud density and cover, decreasing upper tropospheric specific humidity and INCREASING SW albedo and will increasingly do so as the atmospheric level of increasing both cloud density and cover, decreasing upper tropospheric specific humidity and INCREASING SW albedo and will increasingly do so as the atmospheric level of INCREASING SW albedo and will increasingly do so as the atmospheric level of CO2 rises!

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.

The latter effect acts to reduce CO2 sensitivity by increasing the aerosol - sensitive SW tau, increasing both cloud density and cover, decreasing upper tropospheric specific humidity and SW albedo and will increasingly do so as the atmospheric level of CO2 rises!

This was likely an aerosol increase from the increased refining of oil in Texas and more local emissions from cars, whose effect on dimming is enhanced by the humid environment in the SE, and perhaps land - use change -LRB-?).

IPCC2013 SPM - 10 admitted there may be «in some models, an overestimate of the response to increasing greenhouse gas and other anthropogenic forcing (dominated by the effects of aerosols)», but retained the alarming upper limit of 4.5 º C from IPCC2007.

This suggests that the aerosol indirect effect and in particular the increase of cloud cover can serve as a possible explanation to the observed changes in surface illumination.

Yes, it seems huge compared effects of increasing CO2 Abstract: «The 340 nm LER is highly correlated with cloud and aerosol cover becauseof the low surface reflectivity of the land and oceans (typically 2 to 6RU, where 1RU = 0.01 = 1.0 %) relative to the much higher reflectivity of clouds plus aerosols (typically 10 to 90RU).

The scope of the treatments of aerosol effects in AOGCMs has increased markedly since the TAR.

The resulting simulations show the cooling contribution of aerosols offset the ongoing warming effect of increasing greenhouse gases over the mid-twentieth century in that part of the Arctic.

Main problem is that if you expect a huge cooling impact of aerosols, the warming effect of CO2 must be increased too and opposite the other way out.

In the United States, new research from the City College of New York on the effects of particle pollution on weather patterns around Manhattan has shown that aerosols can either increase or decrease local rainfall, sometimes creating situations where one area will be deluged while a neighboring town will remain dry.

Read more: Stanford University Aerosols Also Implicated in Glacier Melting, Changing Weather Patterns Other research examining the effects of soot on melting glaciers and changing weather pattens in South Asia has reached similar conclusions: Beyond increasing atmospheric warming, because the soot coats the surface of the snow and ice it changes the albedo of the surface, allowing it to absorb more sunlight and thereby accelerating melting.