Doing your school research paper on climate change sounds like a great idea! Let me see if I can get you started. I’ll even put a few references at the end in case you want to look those up for your school report. (hint hint!)
First, I totally agree, popular culture is becoming inundated with the buzz words, “green”, “ecofriendly”, and “global warming”, but I’m not sure society is explaining things to you very well. You have some really good questions about what global warming means. Even your pop idol, Miley Cyrus is singing “Everything I read is global warming, going green, I don’t know what all this means…” . And if she doesn’t get it, then why should the adults expect you to understand? The truth is, no one really knows all the answers about the problem. The climate is really complicated and scientists don’t always get things right the first try. It takes them a little while to figure something out, just like it takes you a little while to learn something new. (Remember all those cooking failures when you were young?) But we do know a LOT about climate change. And we do know that something needs to change or we may be in some serious trouble.
Okay, let’s talk about scientist lingo. The scientists who wrote the IPCC (or Intergovernmental Panel on Climate Change) say, “A global assessment of data since 1970 has shown it is likely that anthropogenic warming has had a discernible influence on many physical and biological systems” . So, what does that mean? The report is saying that it’s likely that humans are affecting the world around us. There is even a note that clarifies: ‘Likely’ means 66-90%. So we may -or may not- be affecting the global climate. Well, if that isn’t vague I don’t know what is! But, maybe, just maybe, the statement has to be vague. There were “more than 2500 scientific expert reviewers, more than 800 contributing authors, and more than 450 lead authors” who worked on writing the IPCC report . Okay, so you know how you and I can’t always agree? We are only 2 people. Now, imagine trying to get 800+ people to all agree on the same thing. It would be impossible! All of a sudden that range of 66-90% is looking a little more reasonable. No matter what, all the scientists think it’s more than 50% likely that we, humans, are changing the climate. We are affecting our planet. (Well, there are people who think climate change is not our fault- but if a person can’t believe 800 of the top scientists who all agree, then do we really want to believe them?) The real problem that we should be worrying about is that we don’t know what’s going to happen to Earth under our influence. This is what the scientists are currently arguing about. What can we expect from the climate? What should we do?
Now, imagine you are making pancakes. (It sounds random but just trust me for a minute, okay?) If you add too much salt, then your pancakes start to taste funny. But a couple extra grains aren’t going to make a difference. However, there is some critical mass of salt which ruins the pancakes. And you can’t just take the salt out once it’s mixed up! The pancakes are ruined and you have to start over. This is what we are doing to our atmosphere. Only, we are adding extra carbon and other GHGs (greenhouse gases) to the mix instead of salt. In our atmosphere carbon is measured in parts per million, or ppm, instead of teaspoons.
So how much salt in supposed to be in our climate pancakes? Pre-industrial levels of carbon were around 275 ppm. This is going to be our baseline recipe value. We know from this cool science which uses really old ice that Earth has had atmospheric carbon values between 180-280 ppm for the last 800,000 years. We also know that global temperature is closely correlated to carbon levels . The scientists from the IPCC think it’s “very likely” that GHGs, including carbon, are the cause of global warming (very likely means 90-99%) . We now have 400 ppm instead of the baseline of 275 ppm! Our batter is getting pretty salty. Eww! Salty enough that the scientists are starting to wish we could throw it out and start over. But we only have one planet and one atmosphere. We can’t throw it out and start over. How much more salt are we willing to dump in our mixing bowl and still eat the pancakes?
PS- Let me know if you have any further questions I can help with!
 Cyrus, Miley. “Wake up America.” Lyrics. Breakout. Hollywood Records, 2008.
 Soloman et al. “Summary for Policymakers”, IPCC, Fourth Assessment Report, Workgroup 2, 2007, pg 9.
 Press Flyer announcing IPPC AR4; http://www.ipcc.ch/pdf/press-ar4/ipcc-flyer-low.pdf
 Soloman et al. “Summary for Policymakers”, IPCC, Fourth Assessment Report, Workgroup 1, 2007, pg 3.
 Soloman et al. “Technical Summary”, IPCC, Fourth Assessment Report, Workgroup 1, 2007, pg 24.