Earth & Sky

Climate

JB: Bruce Wielicki, at NASA’s Langley Research Center, is one of thousands of scientists worldwide using satellites to measure climate change.

DB: We asked him why it’s been hard for people to believe that climate is changing. And he said the reason is that the biggest climate “noise” – the biggest variations from day to day or month to month – happen at the local level. That’s why scientists using satellites to observe trends over the whole globe, over time, can see that Earth is warming before most people notice a change.

Bruce Wielicki: People may look around and say, this hasn’t changed so much. This has got to be right, what I see in my backyard. It takes a longer time, unfortunately, for a warming trend to come out of the signal. So unless they’re willing to trust the science community to tell them what the bigger picture is, if they’re waiting for their own backyard to show it, unfortunately they’re not going to see it at that level until you’re well down this path.

JB: Wielicki said it wasn’t until the 1970s that people began using satellites in a serious way to study climate.

Bruce Wielicki: The problem with climate, though, with that data, is that it’s a relatively short record we have. Right? In other words, if we had satellite data over the last 200 years, over the whole globe , we could have convinced people a long time ago as to what is going on.

DB: More at earthsky.org. Our thanks today to NASA. We’re Block and Byrd for Earth & Sky.