As we mark this Earth Day here at WAMC, NASA is doing the same. While the agency’s missions going to and studying space may be flashier and more exciting for some, NASA scientists have been studying this planet for decades. WAMC's Jim Levulis spoke with Dr. Matt Rodell, a NASA earth scientist, about some of his work.
Rodell: People think of NASA is looking out at the stars and other planets. But in fact, one of NASA's important objectives, as it was originally defined by Congress is, looking down at Earth and making measurements of the earth we can use for various things, weather, climate, you know, agriculture, etc. So it's really one of our very important types of observations we make. We currently have about 20 satellites in orbit around the Earth, looking down. And I'll give you an example. If you're interested in something like the water in the soil, and this is important for things like growing crops and plants, etc, or monitoring drought, you couldn't possibly put a soil moisture probe everywhere on earth to make measurements everywhere all the time. But from space, there are basically no limitations. And we have a satellite called SMAP, which is making measurements of the water in the soil, everywhere on Earth, it produces a new map about once every three days. And it's critical for agriculture and drought monitoring, and many other things.
Levulis: And since the launch of NASA's first satellite, Explorer 1 in 1958, what key trends, what major trends has NASA observed here on Earth?
Rodell: Yeah, so we see a lot of things related to both climate change and the direct human impact. So we see things like cities growing, for example, that's an obvious one. But we can also look and see where glaciers are melting. And, for example, the Greenland and Antarctic ice sheets are slowly melting and slipping into the ocean, as you've probably seen on the news. And this is important, because it contributes to sea level rise. And as the climate warms, the rate of this melting has been increasing, it's something that we can measure using NASA satellites. We measure both the melting of those ice sheets, and then also the sea level rise itself. But there are other you know, think of more positive things, you know, some of the satellite measurements we make are useful for predicting agricultural productivity, which then in turn, improves our ability to feed the world. We can monitor fires, and help to extinguish them. So we're doing a lot of amazing things.
Levulis: And speaking of climate change there, you know, I'm speaking to you from Albany, New York. And in the matter of a week here in New York's Capital Region, temperatures hit 80 degrees, and then a storm system dropped more than a foot of snow in some places. Is this variation in weather in such a short time span, is that a result of climate change? Or has that been happening even before?
Rodell: Well, you're always going to find examples going back when they were there's crazy weather even, you know, 100-200 years ago, but it does seem like it's happening more frequently. And one of the reasons you might see this, as people talk about the polar vortex, what that means is that you have this flow of air around the poles, and with climate change, that flow has become less direct. Less of a circle, in fact it starts to get these sorts of waves in it. And when a wave comes down, it can bring cold air and when a wave goes up, you might have warm air coming up from the south. And this is gonna be happening more frequently as the climate warms.
Levulis: And you mentioned a bunch of NASA's work as it pertains to the earth. I understand there's a number of Earth science missions planned for this year. Can you detail some of them?
Rodell: Yeah, so I'm a hydrologist, which means I study the water cycle. So the one that's really most interesting to me is called SWOT. And what SWOT is going to do is make measurements of surface water and river flow. So surface water is in lakes and rivers and, etc, are of course super valuable as a resource for agriculture and for drinking water and, etc. But, but we can't make measurements around the world all the time right now of the river flows. In the US, we have great observations that the USGS makes, and they make those publicly available, but many countries around the world won't share their data. For example, the Nile River in Africa is a hugely important river. And we don't have data from the Nile since 1983. But once SWOT launches later on this year, it will be able to measure the river flows of all the rivers around the world and provide really important data for both scientists and for applied users. Farmers in the US need to know whether they should plant soybeans or corn or something else this year and part of that depends on what's growing around the world and measurements from SWOT and other satellites like the SMAP satellite, these are hugely valuable for understanding and predicting agricultural productivity around the world.
