For an expanded list of misconceptions about climate change see http://www.c2es.org/publications/realities-vs-misconceptions-about-science-climate-change and http://brynnevans.com/Climate-Change-Part1.pdf..
Anticipating Student Questions
(answers to questions students might ask in class)
“What is the difference between climate change, global warming and the greenhouse effect?”According to the EPA: “Global warmingrefers to the recent and ongoing rise in global average temperature near Earth's surface. It is caused mostly by increasing concentrations of greenhouse gases in the atmosphere. Global warming is causing climate patterns to change. However, global warming itself represents only one aspect of climate change. Climate changerefers to any significant change in the measures of climate lasting for an extended period of time. In other words, climate change includes major changes in temperature, precipitation, or wind patterns, among other effects, that occur over several decades or longer.” (http://www.epa.gov/climatechange/basics/)
“How do they decide the temperature of the Earth? Where do they measure it”The most obvious problem is that there is not a single temperature for the Earth but an enormous number of local temperatures that span the range from the Antarctic to the tropics and deserts of Africa. In response to this problem, three groups, two in the U.S. and one in Great Britain, analyze thousands of temperature data sets from all over the Earth and determine average temperatures. Other scientists, paleoclimatologists, examine what is called proxy data including ice core samples to determine historical temperatures.
“How is it possible to keep carbon dioxide gas sequestered underground—won’t it escape to the surface?”One example of carbon dioxide sequestering is in Norway where the captured CO2 is injected into sandstone formations under the ocean—which formerly housed natural gas formations. An 800-foot (250-meter) thick band of sandstone—porous, crumbly rock that traps the gas in the minute spaces between its particles—is covered by a relatively impermeable 650-foot (200-meter) thick layer of shale and mudstone. See “More on climate change solutions” for additional information on sequestering.
“How can climate change produce both droughts and floods—sometimes in the same region?”In general, climatologists are predicting greater extremes in weather due to the changing climate. In addition, if average temperatures increase that could produce two different effects. The first would be more droughts since the higher temperature would mean that water would evaporate more quickly leaving the ground dry. At the same time the warmer atmosphere can “hold” more water which could translate to more severe storms and heavier rainfall. And both could happen in the same region.
“What makes some gases greenhouse gases and others not?”It’s a matter of how bonds are configured in the molecule. If bonds in a molecule allow a temporary dipole to form then the gas may be a greenhouse gas. As the reflected long-wavelength infrared radiation from the Earth strikes the molecule it may cause the bond electrons to shift for just an instant creating a temporary dipole in the molecule and causing the molecule to vibrate excessively. This vibrational motion is the added energy that creates the greenhouse effect in the atmosphere. See ”More on greenhouse gases” above for a little more detail.