The vote of the majority may say more about the convincing power of the ideas than provide an good understanding of the reality. But what do we think?
If CO2 is not the cause of the recently observed warming then what is?
I'll stick with CO2, causing a net increase in global energy balance and amplified by water vapour.
Temporal variability of daily time series for total solar irradiance at the top of the atmosphere, the Microwave Sounding Unit (MSU) based global, hemispherical and zonal average temperature for the lower troposphere and stratosphere together with5 surface air temperature data, measured at various meteorological stations have been studied by means of the structure function. From the growth rate of the structure function in the time interval between 32 and 4096 days it follows that the variability of the series
represents an anti-persistent (AP) behavior. This property in turn shows a domination of negative feedback in the physical system generating the lower tropospheric temperature variability. Distribution of the increments over various ranges and correlations between them are calculated in order to determine the quantitative characteristics describing temporal variability.
CW said:f H2O does not amplify the small CO2 warming then the models must be wrong. In that case how do you account for http://www.gfdl.noaa.gov/reference/bibliography/2002/soden0201.pdf [Broken]
Although it is possible that other processes, such as clouds, could act in place of water vapor to provide the strong positive feedback necessary to amplify the cooling,...
...Although it is possible that other processes, such as clouds, could act in place of water vapor to provide the strong positive feedback necessary to amplify the cooling...etc..."
Andre said:Century-millenium scale oceanic oscillations?
Decadal atmospheric oscillations?
Interacting oscillations all in warm phase currently?
Solar activity, influencing cosmogenic condensing nucei?
land albedo changes due to changed land use?
Oceanic albedo changes (algae) due to anthropogenic disturbing of the food chains?
Airliner water vapour emission in the stratosphere?
I found http://segovia.mit.edu/publications/2002/sretoc.pdf [Broken] interesting.
CobblyWorlds said:land albedo changes due to changed land use? - Warming from gound up, so how can this explain the strato cooling. And would it account for polar amplification? Most of the Earth is ocean, and were such massive albedo to blame then it should be apparent from sattelite measurements.
Oceanic albedo changes (algae) due to anthropogenic disturbing of the food chains? - Again from the surface up heating, stratospheric cooling should not be an indicator. How massive would this need to be for even a 0.5 degC global temp increase? I've never heard of evidence for this. Once again albedo should be apparent with the technology available.
Thanks Andre, I'll stick with CO2, causing a net increase in global energy balance and amplified by water vapour. Off now, will reply tomorrow.
You left out the terracalories of heat generated by human activity
...no major ongoing trend... [cosmic rays seeding clouds]
CobblyWorlds said:Hi Andre,
If H2O does not amplify the small CO2 warming then the models must be wrong. In that case how do you account for http://www.gfdl.noaa.gov/reference/bibliography/2002/soden0201.pdf [Broken]
To the best of my knowledge there is no major ongoing trend in cosmic rays that would account for the observed warming trend. Do you have such infor?
Again I refer you to my point regarding the 11 year solar cycle. Why, if the sun is causing the recent warming does the climate not exihibit an 11 year cycle. After all the 11 year cycle is far greater than and +/- trend in solar radiation (agin to the best of my knowledge - but I could be wrong!)
CobblyWorlds said:Hi Reasonmclaus,
"If one area, of the atmosphere or surface areas, is warming and another cooling it would be likely that changes in heat distribution rather than net warming is occurring. "
I don't quite get what you're getting at here. The global average temp is increasing. CO2 will increase the net energy of the Earth and then this minimal net energy increase (warming) will increase humdity (water vapour concentration) thus increasing the 'greenhouse' capture of heat. Thus the globe warms on average.
CobblyWorlds said:"I have yet to see any numbers indicating that it is possible for CO2 to generate the necessary 500 to 700 calories per gram necessary to heat the atmosphere. CO2 only absorbs a narrow band of IR that is not widely produced."
See IPCC Third Assesment Report Part 6 (I think), there's a table which contains the equations used to account for the increasing saturation of absorption bands as CO2 concentration increases. CO2 increases from current atmospheric concentrations are still able to increase absorbed energy.
PS http://www.gfdl.noaa.gov/reference/...2/soden0201.pdf [Broken] demonstrates the ability of models to correctly reproduce water vapour levels under changes of forcing. Thus the models can be viewed as more robust in their projections of water vapour amplification of CO2 driven warming.
CobblyWorlds said:Hi Reasonmclucus, (got the name right this time)
"The global average temp is mathematically worthless. " Do you mean mathematically or realistically? I really don't know where to start here. Obviously the temperature of an object can be determined by taking mean temperatures and averaging. As to the time of day issue, I don't know how exactly met stations do their work. But we have sondes, ground stations, and satelite all showing a warming. Furthermore this warming appears to be backed up by the pattern of glacial retreat at altitude in the tropics and temperate lattitudes, for just one observation. So that suggests that the measured increase is, at least in trend real.
"the amount of water vapor in the air exists independently of the amount of CO2. " Correct, but CO2 in the atmosphere increases temperature and THAT is what increases water vapour level. In Soden et al, it is shown that the models correctly account for changes in water vapour due to the reduction in solar forcing by aerosol driven albedo changes from Mt Pinatubo.
PS the 2 first links you post to appear to support my contention that Solar activity does not account for the current warming. I can't access the 3rd one, does that stand against what I'm saying?
CW said:PS http://www.gfdl.noaa.gov/reference/bibliography/2002/soden0201.pdf [Broken] demonstrates the ability of models to correctly reproduce water vapour levels under changes of forcing. Thus the models can be viewed as more robust in their projections of water vapour amplification of CO2 driven warming.
The magnitude of this cooling is documented by satellite measurements of lower tropospheric temperature from the microwave sounding unit (MSU). The MSU data indicate a peak global cooling of ~0.5 K nearly 18 months after the eruption, after which the temperature slowly returns to pre-Pinatubo levels.....
The observed anomalies are computed using a 1979 to 1990 base climatology and expressed relative to the pre-eruption value, defined here as the mean anomaly for January 1991 to May 1991.
Indeed, noIs there an increase in strato temps associated with "1982, 1984, 1989." No?
I stand by what I state.
there are three incidents of vulcanism that produced a strato injection leading to strato warming.
The tropo cooling periods you state in 1984 and 1989 do not have a strato warming, therefore they were not due to stratospheric injection of volcanic plumes. So my point stands, citing them does not in any way undermine the conclusions of Soden et al.
The contamination is only a minor fraction, hardly enough to change anything in the trends. I would concur that this contamination introduces some larger error bars in the spikes but it would not remove the spikes and shape them into nicely reproducing aerosol effects.MSU-2 is contaminated by the stratosphere, as stated above. So without the analytical techniques needed to remove that contamination your conclusion is specious.
Yet again I assert: Soden et al's paper supports the model’s ability to model water vapour reaction to a change in forcing.
“There are several sudden lower troposphere cooling events not associated with major volcano aerosol injections.” Yes, and so what?
Not every cooling is due to vulcanism and sometimes the signature of vulcanism is lost because of other factors in the climatic system
I am only concerned with Pinatubo
According to the graph I have always been relying on, http://www.metoffice.gov.uk/researc...r_air_temps.gif , there is a CLEAR drop associated with Agung.
As is seen in the El-Chichon eruption where, as I point out above, the cooling period was already underway thus undermining it’s utility as a scenario for this study