Sentences with phrase «direct effect of aerosols»

I know that aerosols are a complicated issue but frankly speaking, I think that the IPCC estimate for the direct effect of aerosols (+0.5 Wm2) is also too high.

Otherwise, changes in the direct effect of aerosols, for example, would be incorrectly aliased onto cloud forcing.

@Ed Hawkins, I agree that the direct effect of aerosols is good understood, but I have the impression that the models exaggerate their effect.

@FerdiEgb — the direct effect of aerosols is fairly well understood, and produces a cooling effect — it is not just a convenient way to explain the flat period.

So, the direct effect of aerosols is fairly well understood, and produces a cooling effect?

Another source of uncertainty comes from the direct effect of aerosols from human origins: How much do they reflect and absorb sunlight directly as particles?

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

A modeling study of the direct effect of aerosol over the Tropical Indian Ocean.

Not exact matches

This mis - representation and can have significant ramifications for estimating the direct and indirect effects of aerosols on climate.

Most studies consider a range of anthropogenic forcing factors, including greenhouse gases and sulphate aerosol forcing, sometimes directly including the indirect forcing effect, such as Knutti et al. (2002, 2003), and sometimes indirectly accounting for the indirect effect by using a wide range of direct forcing (e.g., Andronova and Schlesinger, 2001; Forest et al., 2002, 2006).

It is rather surprising that adding cloud lifetime effect forcing makes any difference, insofar as Aldrin is estimating indirect and direct aerosol forcings as part of his Bayesian procedure.

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.

Earth's measured energy imbalance has been used to infer the climate forcing by aerosols, with two independent analyses yielding a forcing in the past decade of about − 1.5 W / m2 [64], [72], including the direct aerosol forcing and indirect effects via induced cloud changes.

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).

Can any of the experts lurking here refer me to any updates to the anthropogenic direct effect aerosol radiative forcing digram — Figure 6.8 -(Figure 401) in the TAR?

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.

Thus the balance is that soot has more positive effect than the combined direct and indirect negative effects of sulphate (and other) aerosols.

The top panel shows the direct effects of the individual components, while the second panel attributes various indirect factors (associated with atmospheric chemistry, aerosol cloud interactions and albedo effects) and includes a model estimate of the «efficacy» of the forcing that depends on its spatial distribution.

In their calculations, the direct tropo - spheric aerosol effect does not play a large net role, because the moderately absorbing aerosol assumption leads to an offset between its sunlight reflecting and absorbing properties insofar as the top of the atmosphere irradiance change is concerned.

The direct and indirect radiative effects of biogenic secondary organic aerosol.

In addition, some models include the indirect effects of tropospheric sulphate aerosols on clouds (e.g., Tett et al., 2002), whereas others consider only the direct radiative effect (e.g., Meehl et al., 2004).

To evaluate the global effects of aerosols on the direct radiative balance, tropospheric chemistry, and cloud properties of the earth's atmosphere requires high - precision remote sensing that is sensitive to the aerosol optical thickness, size istribution, refractive index, and number density.

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.

Note, OA stands for Other Anthropogenic factors, primarilly the aerosol direct and indirect effects and Land Use Change, all of which are negative forcings.

As I have pointed out before, it seems to me that a fair evaluation of climate models is impossible when there remains vast uncertainty in aerosol forcing (direct and indirect), and substantial uncertainty in cloud effects.

Forcing estimates for the direct effect of sulphate aerosols and other trace gases included in the DDC models are given in Chapter 6.

This review paper outlines the rationale for long - term monitoring of the global distribution of natural and anthropogenic aerosols and clouds with specificity, accuracy, and coverage necessary for a reliable quantification of the direct and indirect aerosol effects on climate.

Earth's measured energy imbalance has been used to infer the climate forcing by aerosols, with two independent analyses yielding a forcing in the past decade of about − 1.5 W / m2 [64], [72], including the direct aerosol forcing and indirect effects via induced cloud changes.

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).

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.

The spatial patterns of RFs for non-LLGHGs (ozone, aerosol direct and cloud albedo effects, and land use changes) have considerable uncertainties, in contrast to the relatively high confidence in that of the LLGHGs.

In this paper we present results from various field experiments demonstrating the contribution that the multi-angle multi-spectral photopolarimetric remote sensing measurements of the NASA Glory mission will make to the determination of the direct and indirect radiative effects of aerosols.

Several studies have considered the response of a GCM with a mixed - layer ocean to indirect aerosol effects (Rotstayn et al., 2000; K. Williams et al., 2001; Rotstayn and Lohmann, 2002) or to a combination of direct and indirect aerosol effects (Feichter et al., 2004; Kristjansson et al., 2005; Takemura et al., 2005).

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 direct radiative effects of aerosols can be divided in reflection and absorption.

2) A considerable part of that effect (apparently larger than thought before, according to the SOD) is produced by the direct effect; aerosols scatter sunlight and cool the surface.

As it is now, temperature response to volcanic forcing leads events in some cases which is obviously wrong and volcanic (aerosols) forcing direct and indirect effects are the second largest source of model uncertainty.

4) If the temperature of the whole globe is being dragged down by the aerosols direct effect but most of the globe (the majority of the oceans, the polar regions, the deserts,...) is basically unaffected by this DE, it makes sense to look at the instrumental record to see the coolness in the affected industrialized regions that would compensate for the lack of aerosols on the rest of the globe.

A large number of modeling studies have been carried out to characterize the spatial variability in aerosol forcing due to direct, indirect, and semidirect effects (IPCC, 2001).

We refer to the direct and indirect effects of human - made aerosols.

It is rather surprising that adding cloud lifetime effect forcing makes any difference, insofar as Aldrin is estimating indirect and direct aerosol forcings as part of his Bayesian procedure.

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.

The direct and indirect effects of human - related aerosols on radiation, cloud, precipitation, and so on, might play an important role in generating the opposite signal in the weekend effect for different seasons.

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.

Myhre, G., N. Bellouin, T.F. Berglen, T.K. Berntsen, O. Boucher, A. Grini, I.S.A. Isaksen, M. Johnsrud, M.I. Mishchenko, F. Stordal, and D. Tanre, 2007: Comparison of the radiative properties and direct radiative effect of aerosols from a global aerosol model and remote sensing data over ocean.

Yu, H., Y.J. Kaufman, M. Chin, G. Feingold, L.A. Remer, T.L. Anderson, Y. Balkanski, N. Bellouin, O. Boucher, S. Christopher, P. DeCola, R. Kahn, D. Koch, N. Loeb, M.S. Reddy, M. Schulz, T. Takemura, and M. Zhou, 2006: A review of measurement - based assessment of aerosol direct radiative effect and forcing.

The most easily understood interaction between aerosols and climate is the direct effect (scattering and absorption of shortwave and thermal radiation), which is discussed in detail in Chapter 2.

In terms of sulphate aerosols, both the direct radiative effects and the indirect effects on clouds were acknowledged, but the importance of carbonaceous aerosols from fossil fuel and biomass combustion was not recognised (Chapters 2, 7 and 10).

This study will examine the current state of knowledge regarding the direct and indirect radiative forcing effects of gases, aerosols, land use, and solar variability on the climate of the Earth's surface and atmosphere and it will identify research needed to improve our understanding of these effects.

The direct and indirect radiative effects of aerosols suspended in the atmosphere above clouds (ACA) are a highly uncertain component of both regional and global climate.