Let’s look at climate change from a scientific perspective, but acknowledge lay public opinion. About 97% of scientists, based on published peer reviewed papers, and 75% of the lay public, based on opinion polls, believe the current trend in global warming is due to human activity, especially burning fossil fuels. Here are some salient facts:
- According to the Intergovernmental Panel on Climate Change (IPCC), a scientific intergovernmental body under the auspices of the United Nations, the Earth’s climate is warming, as discuss in Chapter 5. The IPCC estimates there is a 95% probability that humans are causing most of it by burning fossil fuels, engaging in deforestation, and using aerosol spray
- According to the United States Environmental Protection Agency, the number one cause of climate change comes from burning fossil fuels, with over 40% due to burning coal to generate electricity and 33% from vehicle emissions.
- Numerous other respected scientific organization, such as the Royal Society, American Geophysical Union, Joint Science Academies, American Meteorological Society, and American Association for the Advancement of Science, also attribute global warming to the human-caused increase in greenhouse gas concentrations
- About 3% of scientists disagree and the popular media have given them strong representation. This in turn has caused significant lay public and political debate, especially in the United States
- The scientific consensus in a “nutshell”: The rapid increase in carbon dioxide, which has almost doubled during the last century to the point it is becoming toxic to numerous species, is responsible for the “greenhouse effect.” {Note: Merriam-Webster.com defines the “greenhouse effect” as follows: warming of the surface and lower atmosphere of a planet (as Earth or Venus) that is caused by conversion of solar radiation into heat in a process involving selective transmission of short wave solar radiation by the atmosphere, its absorption by the planet’s surface, and reradiation as infrared which is absorbed and partly reradiated back to the surface by atmospheric gases}
- Dissenting scientific views: There is no consensus among dissenting scientists regarding the cause of climatic change. Dissenting debate has centered on two points:
- Climate sensitivity – how responsive the climate system might be to any given level of greenhouse gases
- Consequences of global warming – how the climate will respond locally and globally to greenhouse gases
The preponderance of scientific evidence makes a strong case that human activity, especially burning fossil fuels, is responsible for global warming. It points out no scientific body of national or international standing maintains a formal opinion dissenting from any of the main points put forward by the IPCC.