Let me see, I think it goes like this. Burning fossil fuels puts more carbon dioxide in the atmosphere. Carbon dioxide is the earth’s “thermostat”. When you increase carbon dioxide in the air, you increase the temperature, on a linear basis. Don’t worry about the actual mechanical underpinnings of how this occurs, just trust us, it happens. We are heating the earth up immensely, and all the ice on earth will melt, flooding and killing most of humanity. If that doesn’t do it, there will be fires everywhere, massive heat waves that kill people, the heat will cause the spread of disease and the rise of new diseases, there will be climate migration and so on and so on. The solution–make everything electric, which requires massive new sources of electricity–solar and wind primarily. So we will give already rich people massive subsidies to support the businesses that produce these new power sources. That is the climate hysteria/renewable energy scam in a nutshell.
The problem that the hysterics have is that the actual real data and science don’t support this nonsense–either the supposed problem, and certainly not the solution. Somehow the truth keeps leaking out, even in semi-prestigious scientific journals, which are typically fully bought in to the hysteria. So here we see an article in Geophysical Research Letters. Turns out that in our very complex climate system, clouds play a particularly important role in moderating temperature. Clouds affect the amount of radiation hitting the earth’s surface from the Sun and the amount bouncing back into space. Clouds and the rain they produce typically cools the surface below.
The biggest storm cloud zones are in the latitudes surrounding the equator, which also cover the largest portion of the earth’s surface. Those zones have decreased in size over the last 24 years, leading to less cloud cover and more sunlight hitting the earth’s surface, accounting for basically any and all recorded increase in temperatures in this time period, according to the authors’ research. Why they have decreased is not clear. Regulations on ship emissions, primarily sulfur-based compounds, appear to be a factor. It seems quite likely that this is merely a natural variation phenomenon. Climate models have completely failed to produce or predict what has occur, verifying again how useless they are. Of course, the hysterics, which includes most climate “scientists” since they otherwise couldn’t get funding, will attempt to tie this to CO2 increases, but there is simply no evidence to support that hypothesis. (GPU Study)
“When you increase carbon dioxide in the air, you increase the temperature, on a linear basis.”
It is logarithmic, not linear and the warming due to the effect of CO2 alone is a solid fact. That warming leads to changes in the water cycle that somewhat increase the warming (water vapor and lapse rate feedback); that also seems to have a sound foundation. The resulting warming is significant, but not catastrophic.
The thing that produces large warming in climate models is changes in cloud cover (cloud feedbacks) that are assumed to be a consequence of the modest warming produced by CO2 and water vapor changes. That has been entirely speculative, with no real observational support. Observed temperature increases suggest that clouds have little effect on warming.
The study cited would seem to provide observational support for significant cloud feedback. The observed change in forcing is 30-40% larger than the CO2 forcing. That would put climate sensitivity pretty much in the middle of what models predict. But that creates a mystery as to why observed temperature increases have not been larger.
Of course, the changes in cloud cover could be due to a cause other than the small temperature increase, so the cited study does not actually validate the models. But even if it is some other cause, that would not resolve the disconnect between increased forcing and increased temperature. There is still a lot we don’t know.
the hysterics generally claim it is linear–for every step up in CO2 you get a step up in temp
Oh. I just realized that the cited paper only looks at half the cloud effect. Clouds produce cooling by reflecting sunlight (which they measure) and also produce warming by absorbing IR (which they ignore). So the net effect is likely much smaller, or even in the opposite direction of what they report. And that would explain the discrepancy with the observed temperature increase. So the paper does not actually provide support for what is in the climate models. Nor does it undermine the models.
I think the authors considered the total effect of everything on temperature trends, including the totality of cloud effects