rmnka447, on 2017-March-22, 14:54, said:
Geologic records clearly show the climate of the earth has naturally changed throughout its history. Throughout that history there have been periods of global warming and global cooling.
The controversy is over the effect of humans on those natural processes. The argument is that human use of fossil fuels is inordinately increasing CO2, a "greenhouse gas", which is causing accelerated warming of the earth. Based on this thesis, some climatologists have projected, through the use of complex computer models, predictions of the effects of this warming. The most widely reported and referenced model results are the "hockey stick" projections which predict rapid runaway global temperature after something like a 2-3 degree overall average temperature rise.
However, these model projections are not facts, but guesses. So they are only as good as their ability to reflect what is naturally occurring. The problem is that in order to develop these models of extremely complex natural processes, there are many assumptions about these processes that must be made. Some of these assumptions may have massive effects on what the models predict. So if these projections are to be taken as reasonably accurate, some assessment of how these assumptions affect the models is necessary. If a very small change in an assumption yields radically different results from the models, then that's a big red flag about the accuracy of the models. OTOH, if the assumption can have a wide range of values and still get essentially the same results, then one can have a much greater confidence in the models.
Finally, the underlying thesis has to be proven by scientific evidence. Einstein's theory of relativity was not confirmed until his predicted bending of light as it passed by the sun was observed during solar eclipses in the 1930s (I think that's the timeframe). So in the case of the theory of human caused global warming, the exact relationship between CO2 concentrations and global temperature needs to be confirmed.
Skeptics point to more recent global temperature data that is significantly lower than predicted at the given CO2 concentrations as an issue. Their contention is that CO2 may have less effect on global warming than is theorized. They also have concerns with the models assumptions. And in larger sense, they may have concerns about potential natural processes not reflected in the models or projections of the effects of temperature change. (For example, continental levels may rise ["float"] as sea levels rise. Also, the earth may naturally react to rising CO2 levels by increased plant activity which slow the rise in CO2 levels.)
Proponents usually aver "the science is settled" and seem to accept the model projections as dead certain fact. Anyone expressing concerns about those projections is ridiculed and delegitimized.
Perhaps the best we can hope for is some intersection and debate between the scientific skeptics and scientific proponents, so that we can come to a consensus about the most probable long term effect of global warming.
But beyond whatever those conclusions are, there needs to be some debate on how to change to help minimize global warming. Things like eliminating fossil fuels are likely to have a profound effect on our economy and society. So there needs to be some buy in by a super majority of society rather than imposition by governmental fiat. A key component of what we do has to be what impact our actions have overall global warming versus the displacement and change they force. If what we do has little or no impact on the overall result, then maybe the extent of any changes needs to be rethought.
I guess the bottom line is that if one is "right", one ought to be able to persuade those who think differently by the strength and eloquence of one's argument not by just insisting your right.
Take this post to the climate change thread.