A Summary About Man-Made Global Warming and Use of Fossil Fuels By Donald Rapp Ph.D. Chemical Physics Full Professor of Physics and Environmental Engineering, 1973 – 1979 University of Texas Full bio, publications, books, click here Presented to ASME - Energy Committee, March 2014 1. The climate of the 19th century wasn’t all that great. It was particularly cold in mid-northern latitudes. Climates always change regardless of human activity. 2. The earth has warmed in the past 120 years, mostly at high northern latitudes; far less in the tropics or southern hemisphere. In many ways, the climate today is “better” than it was in 1850. 3. We cannot pin down how much of this warming was due to rising greenhouse gas concentrations but it seems likely that some of the warming was due to rising CO2, while some seems to be due to natural variations. 4. As we go forward in the 21st century, world population will increase from 7 billion to over 9 billion, and world energy consumption will increase five-fold. Presently about 80% of world energy is generated from fossil fuels. 5. If we continue to depend mainly on fossil fuels for energy, CO2 will rise further in the 21st century, and will undoubtedly lead to more global warming. Climate scientists have shown themselves to be completely unable to predict how much warming. 6. Potential impacts on the world of further warming in the 21st century due to continued heavy use of fossil fuels have been estimated by a number of scientists, but these range over a wide spectrum ranging from catastrophe to benign. I have studied this at length, and I have tentatively concluded that the most probable outcome is a variety of moderate problems (mainly a rise in sea level) but no catastrophe. Nevertheless, we cannot be sure. 7. Because there is some non-negligible probability of severe impacts from future global warming, it behooves us (us being the world) to try to reduce use of fossil fuels as much as possible in the upcoming years, while still supplying the people of the world with needed energy.
8. Presently, China emits nearly twice as much CO2 as the US, and China continues to accelerate its use of coal. The US emits only about 15% of world emissions. Developing nations (including China) emit more than 50% and they are expanding emissions while US, EU and other developed nations are slowly reducing emissions. 9. Reducing use of fossil fuels while world energy consumption is growing rapidly is a difficult challenge. The potential for solar and wind has been greatly exaggerated by wild-eyed visionaries. Use of nuclear energy may have to be expanded. But no matter how you slice and dice it, there doesn’t seem to be any way to severely cut world emissions of CO2. 10. The real issue in global warming is not whether humans produced warming in the 20th century, or how much further warming we might expect in the 21st century. The real issue is: “What can we do about it?”
Comment by Stephan Savarese, Member AEPN, Association des Ecologistes Pour le Nuclaire, (English: Environmentalists for Nuclear Energy – International), Houilles, France, July 4, 2015. Some have already transitioned into a low-carbon economy and use much less fossil fuels (less than 2 tons per year per person), thanks to fossil-free electricity (15% hydraulic and 80% nuclear in France in 2014) and electricity-powered buildings, vehicles and industrial processes. Comment by John Shanahan, Member EFN-USA, Environmentalists for Nuclear Energy – USA, Denver, Colorado, July 6, 2015. Like it or not, the world will continue to use fossil fuels at the same level or higher for the coming centuries, until there is sufficient additional nuclear power or some other source. It is unproductive, even counter-productive, to use not fully valid reasons for trying to force reduction of use of fossil fuels.
Comment by Donald Rapp, Former Full Professor of Physics and Environmental Engineering, University of Texas 1973 – 1979, July 7, 2015.
While I think that climate models leave much to be desired, and global understanding of the quantitative relationship between greenhouse gas concentrations and global climate is also quite fragile, there is enough evidence to suggest that continued business as usual emission of greenhouse gases in the 21st century raises the possibility of some serious consequences for the world. Therefore, it would be prudent for the world to take action to reduce greenhouse gas emissions to the degree possible in the remainder of this century, subject to the constraints: (1) that the world needs energy, and energy consumption will probably rise by a factor of five from 2000 to 2100, and (2) the methods used to reduce emissions must not be so costly as to bring on economic depression. Unfortunately, developing nations need fossil fuels to expand their economies, and coal is particularly appealing to China, India and others. Were it not for China, and to a lesser extent India, I would hope that indeed, we could gradually reduce world CO2 emissions in the decades ahead. The phrase you used above suggests that we should not reduce dependence on fossil fuels without valid reasons. I think we do have valid reasons. Not cast in stone. Not certain by any means. No smoking gun. But enough circumstantial evidence exists that if we have the means to reduce emissions, and can still supply the people with needed energy, we should certainly do that, even if the danger is not proven 100%.
Donald Rapp