Sentences with phrase «if aerosol levels»

Not exact matches

Even if the concentrations of all greenhouse gases and aerosols had been kept constant at year 2000 levels, a further warming of about 0.1 °C per decade would be expected.

does fit the temperature trend to an acceptable level, if one should reduce the sensitivity for CO2 / aerosols far enough... Current models also can reproduce other transitions (LGM - Holocene) with a reasonable accuracy, but this is mainly in periods where there is a huge overlap between temperature (as initiator) and CO2 / CH4 levels (as feedback).

There's the complication that if CO ₂ stays level the amount of human - created aerosols would presumably reduce.

If the influence of aerosols is less than expected, then the influence of CO2 must be decreased too, or it is impossible to explain the cooling period 1945 - 1975 with increasing CO2 levels.

Firstly you don't know what else outside the aerosol system might have happened while aerosols were present, if the other factors (CO2 / sun / El Nino / etc) were rising while the aerosol even occurred of course temps can rise above «that level.

Even if the concentrations of all greenhouse gases and aerosols had been kept constant at year 2000 levels, a further warming of about 0.1 °C per decade would be expected.

does fit the temperature trend to an acceptable level, if one should reduce the sensitivity for CO2 / aerosols far enough... Current models also can reproduce other transitions (LGM - Holocene) with a reasonable accuracy, but this is mainly in periods where there is a huge overlap between temperature (as initiator) and CO2 / CH4 levels (as feedback).

I'm pretty sure you can get the grey version of that into a strat - cooling / trop - warming situation if you pick the strat absorbers right, but Andy is certainly right that non-grey effects play a crucial role in explaining quantitatively what is going on in the real atmosphere (that's connected with the non-grey explanation for the anomalously cold tropopause which I have in Chapter 4, and also with the reason that aerosols do not produce stratospheric cooling, and everything depends a lot on what level you are looking at).

At least with a model like the MIT one used in Forest 2006 one can (if the descriptions of it are correct) set the key climate sensitivity, effective ocean diffusivity and aerosol forcing levels independently and with some confidence (I'm not the person to ask how much) that the simulated results reflect those settings.

Even if the concentrations of all GHGs and aerosols had been kept constant at year 2000 levels, a further warming of about casino 0.1 °C per decade would be expected.

If I'm reading the chart correctly, aerosol forcing (the non-volcanic kind) did not level off until 1991.

2) IPCC: «Even if the concentrations of all greenhouse gases and aerosols had been kept constant at year 2000 levels, a further warming of about 0.1 °C per decade would be expected.»

If analysis of historical data on GHG rise and net effects of aerosols establishes beta = 0.5, then TCR = 1.2 C. But, beta is uncertain and might be as low as 0.4, in which case TCR = 1.3 C. But, TCR (1 + beta) = 1.8 C and only has uncertainty introduced by uncertainty in the historical GMST and CO2 level rise.

«warming in the pipeline» usually assumes constant concentrations, not zero emissions (though if CO2 emissions were dropped to zero tomorrow, and all other emissions were held constant, I'd probably expect a little bit of warming before it turned over and started dropping) 2) Don't forget aerosols: they are following the Level 1 scenario from Wigley et al. 2009, and may actually dominate short - term temperature trends.

I would be happier if they compared what they believe the relative effects of CO2 and aerosols to be, then run these values through the known CO2 / Dust levels in the ice cores.The higher the value that aerosols cool, the less sensitive the planet is to CO2.

Even if the concentrations of all greenhouse gases and aerosols had been kept constant at 2000 levels, a further warming of about 0.1 °C per decade would be expected.

Even if the concentrations of all greenhouse gases and aerosols had been kept constant at year 2000 levels, a further warming of about 0.1 °C per decade would be expected» (AR4 WG1 SPM p12)

Even if the concentrations of all greenhouse gases and aerosols had been kept constant at year 2000 levels, a further warming of about 0.1 °C per decade would be expected» (p12)

well, if it turns out to be useful for weather forecasting and dynamics at that level, perhaps it would prove useful in reducing the rather large uncertainty the GCM have with clouds and aerosols?

Hi Karsten, If you're still reading this, I'm still trying to get my head around the notion that we don't need to see much cooling under the most aerosol - laden areas for the direct effect to be strongly negative at the global level.

Atmospheric carbon dioxide equivalent levels were around 455 ppm CO2 - e in 2005 if you ignore the cooling effects of aerosols but around 375 ppm CO2 - e in 2005 if you include the cooling effects of aerosols and landuse changes: see the IPCC (2007) Working Group III report at page 102, available at http://www.ipcc.ch/pdf/assessment-report/ar4/wg3/ar4-wg3-chapter1.pdf.

If there indeed was this slowdown in sea level rise, aerosols and ENSO would seem to possibly account for everything, including Figure 1 above.

If the low level aerosols act to actually warm, then it would be a highly regional warming, since the plumes would not have altitude sufficient to hold them aloft for long.

That seems the clearest statement yet of the real problem == is there anything that can replace current levels of air pollution, if high sulfur coal and oil are phased out for respiratory health reasons, that would make up for the loss of the aerosols» negative forcing on global temperature?

IPCC: Even if the concentrations of all greenhouse gases and aerosols had been kept constant at year 2000 levels, a further warming of about 0.1 °C per decade would be expected http://bit.ly/caEC9b

The estimated warming of 2.4 °C is the equilibrium warming above preindustrial temperatures that the world will observe even if GHG concentrations are held fixed at their 2005 concentration levels but without any other anthropogenic forcing such as the cooling effect of aerosols.

But one thing all aerosols have in common is that if you are going to balance the greenhouse effect due to increasing levels of carbon dioxide, you must keep increasing the amount of aerosols — which will then increase the negative effects associated with them — including diminished agricultural output and climatic side - effects — as they will not evenly counteract the effects of increased carbon dioxide and its water vapor feedback due to evaporation.