Science has arrived at a powerful consensus about climate change and man's role in it. The statistic most often sighted is that 97% of scientists agree that man is the major element in moving the climate to a warmer state such that ecological disaster will ensue. Trump regards climate change as a hoax and those who understand the situation know what a joke that is. But Trump is catering to a broad base of climate change denial that spans the plectrum of the Republican party,.
The Trump supporters are trying to fight back against the resistance and one trick they have latched upon is to create confusion about the 97%. This tactic is used to its best advantage in an article by Alex Epstein in Forbes magazine:
What you'll find is that people don't want to define what 97% agree on--because there is nothing remotely in the literature saying 97% agree we should ban most fossil fuel use.It’s likely that 97% of people making the 97% claim have absolutely no idea where that number comes from. If you look at the literature, the specific meaning of the 97% claim is: 97 percent of climate scientists agree that there is a global warming trend and that human beings are the main cause--that is, that we are over 50% responsible. The warming is a whopping 0.8 degrees over the past 150 years, a warming that has tapered off to essentially nothing in the last decade and a half.
The evidence is quite clear about what is agreed upon, Before getting into that, we really should observe that this is a straw man argument. He says climate changers are not being specific because there is no quote that says 97% agree we should ban fossil flue.Most people are just not conversant with the literature. Most policy makes don't agree with such an immediate ban, not even the most liberal. Most thinkers will support some kind of phase in so as to allow the market to replace fossils fuel. This radical issue which no one argues for indicates a straw man argumnet that is being used to create a hermeneutic of suspicion and cast a poll over the 97% quote.
The argument that spreads the warming averaged over 150 years is totally bogus because the high end is within the last few decades. In other words if you average it then it spreads out and is only 0.8 but if you look at where the increases come year by year a very significant tend toward major warming develops. We can see from this graph presented by NASSA that this is the case. "Temperature data from four international science institutions. All show rapid warming in the past few decades and that the last decade has been the warmest on record. Data sources: NASA's Goddard Institute for Space Studies, NOAA National Climatic Data Center, Met Office Hadley Centre/Climatic Research Unit and the Japanese Meteorological Agency."
Chart from NASSA article.
Multiple studies published in peer-reviewed scientific journals show that 97 percent or more of actively publishing climate scientists agree: Climate-warming trends over the past century are extremely likely due to human activities. In addition, most of the leading scientific organizations worldwide have issued public statements endorsing this position. The following is a partial list of these organizations, along with links to their published statements and a selection of related resources.
The academies of science from 80 contrives plus many scientific organizations that study climate agree that man is the crucial factor in climate change and global warming. Naomi Oreskes, Peter Doran, William Anderegg, Bart Verheggen, Ed Maibach, J. Stuart Carlton, and John Cook have authored their own climate comsen sus studies a nd came o the sameconslusiomn which they discuss in a paper they co aiuthoried,Their findkgs:
1) Depending on exactly how you measure the expert consensus, it’s somewhere between 90% and 100% that agree humans are responsible for, with most of our studies finding 97% consensus among publishing scientists.
2) The greater the expertise among those surveyed, the higher the consensus on human-caused global warming.
John Cook Backs this up in an article in Bulletin of the Atomic Scientists:
Now, we have a new resource to dispel the myth that there is a lack of scientific consensus on climate change. While a number of past studies have measured the level of scientific consensus on climate change, no one has published a summary of the many consensus estimates—until now. In a paper published in Environmental Research Letters on April 13, I collaborated with the authors of seven of the leading consensus studies to perform a meta-study of meta-studies synthesising the research into scientific consensus on climate change. (A meta-study combines the findings from multiple studies.) Among climate scientists, the estimates of consensus varied from 90 to 100 percent, with a number of studies converging on 97 percent, the very figure derided by Cruz, Santorum, and others opposed to action on global warming.
A key finding from our meta-study was that scientific agreement was highest among scientists with the most expertise in climate science. This meant that groups with lower climate expertise showed lower agreement on climate change. The group with the lowest level of agreement—at only 47 percent—were economic geologists, who study metals and minerals that can be used for industrial and economic purposes. Conversely, the group with the highest level of agreement—at 97 percent—were climate scientists who were actively publishing climate research.Notice that all of these opinions are tied to research, They are based upon studies they are the opinions of the researchers, Notice that the higher the level of expertise the srtronger the agreemrny with the thesis. What is being agreed with is clear, that humans are the catylist in excellerating global warming,
 Alex Epstein, "97% of Climate Change Scientists Agree is 100% Wrong," Forbes (Jan 6, 2015)
http://www.forbes.com/sites/alexepstein/2015/01/06/97-of-climate-scientists-agree-is-100-wrong/#78f02c557187 (accessed 2/7/17)
 NASSA, "Scientific Consensus: Earth's Climate is Warming," Global Climate Change:Vital Signs of The planet. website published by NASSA Holly Shaftler site ediotor, last updated (Jan 31,2017)
http://climate.nasa.gov/scientific-consensus/ (accessed 2/7/17)
 John Cook, "The 97% Consensus on Global Warming, " Skeptical Sciece Website (2017)
 John Cook, "Yes there Really is Scientific Consensus On Climate Change." The Bulletin of The Atomic Scientists (April 13,2016) on line version URL: