Friday, March 21, 2014

Climate Change: Part 2 How Science Works

Note: This program first aired March 8, 2014.

It’s the nearing the end of winter (we hope), and most of us in North America are sick of the cold, I know I certainly am, and I love winter! Taken in this context, a warmer climate doesn’t sound that bad. Maybe you or some one you know has even questioned how “global warming” (as it is called in the popular literature) can be real if we are having such a cold, hard core winter. Actually, global warming is a misnomer. The warming part refers to the increase in mean or average global surface temperatures, but that is just an average. We can average both 0 plus 10, and 4 plus 6 and get 5 each time. The range between 0 and 10 is much greater than the range between 4 and 6 yet both data pairs tell us the same story when averaged together. Averages are necessary when looking at climate, because climate is a global phenomenon, the result of a global system. The Earth has warmed approximately 0.7 degrees C (or 1.25 degrees F) in the past 100 years. But don’t let the average warming lull you into the dream of the end of winter, while its likely that winters may be getting milder, more heat in the climate system ultimately means more instability, and more chaos in weather patterns. This instability can mean things like what happened this winter, with the polar vortex wandering south, are also likely.

At least if you are questioning the veracity of climate change this winter, you are doing so based on evidence, the evidence being its cold! How can this be a sign of global warming? I applaud you for looking around and actually observing what is happening in the world around you, and making connections to things you have heard are supposed to be happening. The problem is, climate isn’t quite that simple and as a result, we shouldn’t really be calling it global warming. The phenomenon is global in scale, and most of us operate on a human sized scale of observation. So where you are at any give moment (or many many moments this winter), may seem colder than usual, that doesn’t mean that on average, Earth isn’t warming up, it is.

The hardest conversations to have are those with people who don’t “believe” in climate change. Not believing in climate change is sort of like not believing in gravity. Its not believing in how science explains things in the world. Not believing in how science works is always a choice, but people need to understand the implications of that choice. Science seeks to explain natural phenomena through observing, collecting evidence, testing and establishing attribution or cause and effect.

Sometimes science misses the truth because it isn’t asking the right questions, or asking enough questions. That isn’t the case this time around. There are so many scientists working so hard on this issue, from so many different angles; we’re not missing any big picture components. There is so much evidence that has been documented, about how the climate system works, what makes is shift, how it shifts, how fast it shifts. There is a lot we don’t know in this exciting field of inquiry, but the big picture mechanisms of the climate system are well established.

So do me a favor, and when you want to have a conversation about climate change, don’t start it with anything having to do with belief. While there are philosophical discussions to be had about any topic, including climate change, whether or not it is happening and whether or not it is being caused by our carbon dioxide emissions is a question for science. If you want to deny climate change, you need to do so based on evidence, and good luck with that, because the evidence is pretty overwhelming! And by evidence I don’t mean what the talking heads on CNN or NPR or Fox News or some nutty lady on community radio says. Get as close as you can to the source, the people doing the investigating. They are the ones in the trenches, looking at this day in and day out. And I’ll tell you, they are pretty alarmed with what they are learning.

We’ll look more at the climate system and what scientists are finding so alarming in the coming weeks.

There is SO MUCH information out there on the web about climate change, but some of the nicest and most concise is from NASA’s Earth Observatory: