Sentences with phrase «total aerosol effect»

... «I argue that the current agreement of model simulated and observed warming (given the other forcings) points towards a relatively small total aerosol effect.»

Five years ago he noted, «First, the most likely and obvious (although not the only) interpretation... is that the total aerosol effect is smaller than suggested by most aerosol models.»

Not exact matches

We don't know the total forcing that well, primarily because we don't know the aerosol (direct or indirect) effects.

The total of -0.7 W / m ^ 2 is the same as the best observational (satellite) total aerosol adjusted forcing estimate given in the leaked Second Order Draft of AR5 WG1, which includes cloud lifetime (2nd indirect) and other effects.

In addressing the question of the effects of greenhouse gases on Atlantic tropical storms, it might clarify (and even partially defuse) the controversy to lump internal variability together with other forced responses (particularly aerosols), rather than to focus on internal variability vs the total forced response.

Given the total irrelevance of volcanic aerosols during the period in question, the only very modest effect of fossil fuel emissions and the many inconsistencies governing the data pertaining to solar irradiance, it seems clear that climate science has no meaningful explanation for the considerable warming trend we see in the earlier part of the 20th century — and if that's the case, then there is no reason to assume that the warming we see in the latter part of that century could not also be due to either some as yet unknown natural force, or perhaps simply random drift.

The NIPCC report makes the * opposite * claim as Lindzen does, namely that «The IPCC dramatically underestimates the total cooling effect of aerosols.»

The contribution of greenhouse gases is greater than the observed warming, while the total anthropogenic contribution is thought to be around 0.7 °C because of the cooling effect of aerosols.

In the very long term, a warming limit of 1.5 C requires total greenhouse - gas concentrations — plus the effects of aerosols — to be below a level of 400ppm CO2eq.

Given our very short and spotty data on the relative abundance (or importance) of the majority of these aerosols, and given our very poor understanding of the direct, indirect, and side effects of the majority of these aerosols, any numbers that anyone generates about their abundance, importance, or total radiative forcing are going to be a SWAG.

CO2 doubles its 1850 value of 285 ppm), then the total AGW temperature rise due to a doubling of CO2 levels and cumulative effects of all other GHG and aerosols is TCR (1 + beta).

Your comment that the total effect of aerosols since the industrial revolution has been negative is largely true only up to 1972.

The total effect of aerosols since the industrial revolution has been negative.

From the IPCC AR4 report, FAQ2.1, Figure 2, the net effect of anthropogenic aerosols is clearly negative (cooling), totalling about -1.2 W / m2 since the dawn of the industrial era in 1750 to 2005.

However, the total influence on monsoon precipitation of temporally varying direct and indirect effects of various aerosol species is still not resolved and the subject of active research.

However the CMIP5 models show no particular correlation between ECS and total forcing or effective aerosol forcing (which includes the indirect effect).

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:

They get > 100 % because they argue that the anthropogenic warming effects have to overcome the aerosol cooling (and therefore give the same net warming as the total warming since 1950), though most people count aerosols as part of the anthropogenic effect, which causes the confusion.

The total CO2 equivalent (CO2 - eq) concentration of all long - lived GHGs is currently estimated to be about 455 ppm CO2 - eq, although the effect of aerosols, other air pollutants and land - use change reduces the net effect to levels ranging from 311 to 435 ppm CO2 - eq (high agreement, much evidence).

This is AF, not RF, since the observed NH and SH temperatures on which it is based reflect all effects of aerosols - they can not and do not distinguish the main RF component from the total AF.

In fact, most of the GCM studies of the indirect aerosol effect used sulphate as a surrogate for the total anthropogenic fraction of the aerosol (e.g., Boucher and Lohmann, 1995; Feichter et al., 1997; Lohmann and Feichter, 1997).

In any event, all of these calcs are B S because we don't really understand the sum total of past / present and future aerosol effects nor of CO2 feedbacks nor of the combo of CO2 feedbacks with changing aerosols nor of natural low frequency climatic variation.

(The total anthropogenic forcing includes other GHGs and aerosols; the net effect happens to be (with significant error bars) similar to that from CO2 alone.)

shows that natural VOC induced aerosols above the boundary layer are mostly of natural origin (7:1), and comprise a 2:1 up to > 10:1 amount, compared to SOx (SO2 + sulfate) aerosols in the 0.5 - 10 km free troposphere, or 10 % of the total aerosol optical depth measured by satellites... Add to that the effect below the boundary layer and the effect of other natural aerosols (natural fires, sea salt, sand dust, DMS, NOx), good for some 38 % of the < 1 micron fraction of total aerosols (according to IPCC estimates)...

During a dry winter, the reduction of aerosol concentrations in weekend days may overwhelmingly impact on the DTR through a direct effect, i.e. by increasing total solar irradiance near the surface and raising the daytime temperature and maximum temperature, and lowering relative humidity.

There are only a handful of published estimates for total anthropogenic aerosol forcing, including first indirect and cloud lifetime effects.

To calculate total warming and cooling potentials, the total effect of aerosols and greenhouse gases (GHG's) needs to be calculated.