The number of times heads comes up when you toss a coin, number of students present in class, number of times a person has attended therapy sessions-these are all discrete variables. To help see the difference between continuous and discrete variables, imagine a really tall mountain with a trail leading up to the top.
Climate changes resulting from greenhouse gas increases could also significantly affect water supply and demand. For example, a local increase in temperature of several degrees Celsius could decrease runoff in the Colorado River Basin by tens of percent (25, 48).
And scientists say that unless we curb global-warming emissions, average U.S. temperatures could increase by up to 10 degrees Fahrenheit over the next century. Q: What causes global warming? A: Global warming occurs when carbon dioxide (CO2) and other air pollutants and greenhouse gases collect in the atmosphere and absorb sunlight and solar radiation that have bounced off the earthâs surface.