The Veritasium YouTube channel produced the following short video responding to 13 misconceptions about global warming in about 30 seconds each:
Click above for links to additional information.
The video is quite good, but it omits (presumably for brevity) a number of facts that would further underscore what’s being said. For just one example, there’s even clearer evidence than that provided by carbon isotope ratios that rising atmospheric carbon dioxide comes from burning fossil fuels: For decades we’ve been directly measuring the CO2 increase so we know how much is being added to the air. We also know how much fossil fuel is being burned and how much CO2 that releases. Put them together, and it’s obvious that fossil fuels account for every bit of the measured additional CO2 and a good bit more besides. (What happens to the rest? It’s taken up by the oceans, plants, and other things that for thousands of years have kept CO2 pretty much in balance until those natural mechanisms were overwhelmed by fossil fuel use.)
As I noted in a previous post, by the 1950s it was widely acknowledged that burning fossil fuels would predictably lead to global warming and resulting climate change, and a report from the National Academy of Sciences in the mid-1960s included a section on CO2 in an analysis of various forms of air pollution. The fact that some climate scientists in the 1970s were concerned about potential cooling might sound like a complete contradiction to what was said before and after, but there was much less disagreement than you might suppose.
The concern was that aerosol pollutants in the atmosphere might increase the Earth’s “albedo” (or reflectivity) enough to cause cooling. (“Aerosols” here refers not to spray cans but to droplets and particles suspended in air, such as smoke, haze, or clouds.) In fact, aerosols can and do reduce the amount of sunlight reaching the surface, as has been observed after large volcanic eruptions, for example. The question was whether this would overwhelm the warming caused by the increase in greenhouse gasses. Both effect are real, but it’s now clear that greenhouse warming dominates over the tiny albedo change. There has since been some discussion of whether it would be possible to increase the Earth’s albedo deliberately in order to offset global warming, but this could cause more harm than good.
Update (2016 May 30): Another thing worth noting is that the term “climate change” isn’t new or a replacement for “global warming.” Both terms have been in used for decades. The largest scientific body studying global warming (also the largest scientific collaboration in existence) is called the Intergovernmental on Climate Change, and it’s been around (with that same name) since the Reagan administration. Scientific articles referring to global warming as “climate change” go back at least to the 1950s. For more about that, see this post.