Last week the UN’s Intergovernmental Panel on Climate Change released its long-awaited Fifth Assessment Report, putting together the work of over 830 authors and editors, based on millions of measurements to again conclude that “it is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century.” The panel found that it is between 95 and 100 percent likely that the burning of fossil fuels and other human activities are the main cause of the earth’s warming since the 1950s. The panel increased their certainty by five percent from the last report in 2007.
Even with this high level of certainty, skeptics — including almost 58 percent of congressional Republicans — refuse to acknowledge the scientific evidence regarding man-made climate change. This is particularly puzzling considering the scientific consensus in other fields often goes unquestioned even when there is less certainty. As AP reported, 95 percent certainty is a lot more certainty than we have on many things that we simply take as fact. Here are some examples:
1. That reading in the dark is bad for your eyes
Many of us have been told by our parents not to read in dim light or the dark lest we harm our eyes. While there has been little evidence that the lack of light is directly responsible for loss of eyesight, the squinting and close-range reading often required can lead to myopia down the road. In any case, most people avoid the headache and simply leave their lamp on for a little bit longer.
2. That vitamins are a good form of nutritional supplements
Although most of us were always encouraged to take our vitamins, there are a variety of new claims disputing the effectiveness or even
safety of these nutritional supplements. They attempt to weigh the pros and cons of taking vitamins, pointing out that it always helps to read the label first. At the end of the day (or for most people, the beginning), however, if your doctor approves then you’re likely good to go.
3. That drinking while pregnant causes birth defects
While heavy drinking during pregnancy has been shown to have adverse effects on the baby’s health, there is not concrete evidence that the occasional glass of wine or beer will harm your unborn child. Still, most mothers (and doctors) see it as an unnecessary risk, and you would be hard pressed to find an expectant mother partaking in public given the social stigma attached to public drinking while pregnant.
We also are less certain about the dangers of smoking, or what happens from exposure to toxic chemicals.