NASA Podcasts

› Download Vodcast (362MB)


The DUST Project
- Paul Adams
- Chip Trepte
- Rich Ferrare
- Olga Kalashnikova
- Paul Jones


ANNOUNCER: Does the co-host have what it takes to collect and analyze dust data? NASA EDGE travels from coast to coast talking with NASA atmospheric scientists and educators from Project Dust to explore the unique connection between aerosols and climate change.


CHRIS: Franklin, you know I really think we’re wasting time out here. Why is Blair calling us to the beach today?

FRANKLIN: He seems to think he can do his own dust study.

CHRIS: Dust study?

FRANKLIN: Yeah. You know they say dust can travel from Africa and China all the way around the world. So, he thinks he’ll find some out here on the beach.

CHRIS: Yeah, but that’s why we have satellites and special equipment for that.


CHRIS: Wow. What’s he got?

FRANKLIN: I think that’s an air filter.


CHRIS: Is he trying to collect dust with an air filter?

FRANKLIN: Hey look, I’m going to go down here and help him out.

CHRIS: I’ll tell you what I’m going to do. I’m going to go back to NASA, get on the phone and get someone out here and show him how to really collect some dust.

FRANKLIN: Do that.

CHRIS: All right. Hey, tell your boy to wear some sunscreen.

FRANKLIN: Will do. Hey man, what’s going on?

BLAIR: Oh hey, Franklin. Wait, wait. I just want to make sure if any dust particles I’m collecting, I don’t want them to get in your eye.

FRANKLIN: That’s cool.

BLAIR: Ah man, I’m not doing too well.

FRANKLIN: That’s just a regular household filter.

BLAIR: Household, dust collecting air filter, that’s what they collect, right?

FRANKLIN: That’s true.

BLAIR: Yeah, I’m just not getting anything. I’m starting to doubt whether this whole African dust thing and Chinese dust thing is even real. Nothing.

FRANKLIN: Let me check your technique again.

BLAIR: Up here in the air collecting…do you think that will make a difference? I can’t tell if you’re getting anything or not. Bring it down. Bring it down. Oh snap, pay dirt. Oh, that’s awesome! That’s great! Oh, hang on. I’ve got to get data on this. Incredible. All that from altitude, huh? Interesting. The only thing now is whether that’s African, Chinese, or straight Virginia dust. [lips smacking]


BLAIR: Inconclusive.

BLAIR: Now Paul, I understand you had a very successful workshop this week.

PAUL: Yes, we did. We’ve been spending the week with teachers helping them understand the role of dust and climate change. Or are the fact that climates are changing and the amount of dust changing? Helping them learn some things, get some ideas and prepare them to go into the academic school year to develop lessons and video casts for their students to use and helping them learn about this.

BLAIR: We’re here in the wild, let’s say, and this is pretty far from the industrial complex. Is there any dust that the teachers can actually study?

PAUL: You know what? It’s like that song from Kansas, Dust in the Wind, there’s always dust in the wind. Myself, I’m from Kansas. We see dust storms all the time.

BLAIR: Wait. You’re from the band, Kansas?

PAUL: Well, not quite, not quite. From the state, the great state of Kansas, as we say.

BLAIR: Oh. Gotcha.

PAUL: But there we have dust a lot. But that dust gets blown up in the air travels around the world. One of the things the teachers were looking at, were studying the dust from China can actually go all the way around the world. And drop material everywhere across the way, even right here in Syria, Virginia.

BLAIR: That’s just mind-boggling. I still can’t comprehend that.

CHRIS: It’s hard to fathom sometimes that weather that may be on the opposite side of the Earth affects us here at home.

CHIP: One of the things that’s interesting when we think about climate is that it operates on different scales, like different organs in the body.

CHRIS: Right.

CHIP: But they’ve got to work together. So, sometimes something occurs on a small scale but it can actually feed the larger scale, larger weather systems. And those larger weather systems control the smaller scale systems. Like today, will we have thunderstorms or not? They all interact across these different vast scales and we can’t think about things in isolation. We can’t think just about Virginia but we have to think about our surrounding areas and actually the oceans. The ocean temperatures actually influence our weather here in the winter or the summer. We need to understand how they feed across these differences, out to the oceans and back to the land.

BLAIR: Richard, this really kind of odd to me. A lot of people when they think of dust, it’s something you want to avoid, or try to get rid of, but you actually study it. Why are you studying dust?

RICHARD: We trying to study dust to look at its impact it has on atmospheric radiation and climate. Dust has a large impact on climate because it scatters and absorbs light. We here at NASA Langley design instruments, both aircraft as well as space-based instruments, to take measurements of the properties of dust and how it impacts climate. For example, in this aircraft behind us we have a LIDAR system, laser radar, where we send pulses of light. We look at the light that gets scattered by the aerosols and we provide detailed measurements of the altitude of the aerosols, as well as their optical properties. How much of the aerosol is there; how much they scatter and so on.

BLAIR: Aerosols?

RICHARD: Are small particles, either solid particles or liquid drops. If you look out on a hazy day in the summer time, it looks very hazy. Those are all little, small aerosol particle. Dust is another big type of aerosol particle. There’s a lot of dust globally.

FRANKLIN: Dust is also an aerosol.

OLGA: Yes.

FRANKLIN: But what makes dust different from other aerosols?

OLGA: Dust is a different particle. It has a variety of shapes and it can also be made out of different materials. Dust is actually the only aerosol that absorbs sunlight at all the range of the spectrum, from UV to infrared and in that way it could effect our climate differently from other aerosols. Because dust is non-spherical and made out of different material, it scatters sunlight very differently. With a satellite, we are actually able to see that scattering process. By interpreting satellite signal back, we can interpret what that is made out of or basically three important terms; size, shape, and composition.

FRANKLIN: Now you say dust is non-spherical. Spherical aerosols actually have moisture or water in them?

OLGA: Yes, most of the particles, but for dust they are not hydrated. They are made out of little cell particles or little minerals. And minerals by definition are silicas. They are not hydrated. So when dust gets in the atmosphere, it doesn’t matter if there is some humidity, it remains non-spherical. That’s why you have to worry about dust and interpreting our satellite signal.

BLAIR: What are some examples of natural aerosols?

RICHARD: Dust you get from the Sahara or the Gobi Desert in China or sea salt. When you look out over the waves at the beach and you see all the foamy bubbles, there’s a lot of that produced globally.

BLAIR: So, you’re literally getting dust out of the ocean?

RICHARD: You’re getting aerosol particles called sea salt particles out of the ocean, correct.

BLAIR: We can’t catch a break on dust. It’s everywhere.

RICHARD: That’s correct.

PAUL: What we’re trying to understand is if something happens in Africa in terms of farm practices or agriculture or if there’s a drought in the area, how does that change the amount of dust that gets picked up by the winds and transported around the world and comes here? Because there are things even here we might do differently that can effect what happens to different parts of the world. We are getting more droughts. Droughts are coming up in Arizona, places like Texas, Kansas, where we’re having less rainfall. The land is drying. It’s beginning to become more desertfied, more like a desert, and we’re getting more dust in the continental United States, which will have a large impact.

BLAIR: Now you mentioned the desert. In your studies, here at NASA, you’re actually seeing dust or aerosols from the Sahara desert?

RICHARD: That’s correct. We’ve been in missioins, particularly over the Caribbean Sea as well as over the Atlantic Ocean, where we’re seeing large amounts of dust come from the Sahara Desert. These are transported typically in the summertime or early fall every year. In fact, this dust can have impacts on hurricanes and tropical storms that affect this area but we also see a lot of dust that comes from China. In fact, even this time of year, typically March and April there’s a large amount of dust that comes from the Gobi Desert that’s transported globally.

BLAIR: All right, how in the world are we getting dust from the Sahara and China here? How is that even possible?

RICHARD: If the winds are strong enough, dust can get pretty high in the atmosphere and with the large wind speeds that we have, they can be transported long distances. When you fly a jetliner, you often run into winds that are 100 miles an hour. The dust typically stays in the atmosphere for several days or up to a week. So, with winds that strong, they can travel large distances.

FRANKLIN: When we talk about dust, we’re actually speaking about dust storms and how dust is kicked up into the atmosphere. That’s where MISR takes over, right?

OLGA: Yeah, because MISR can actually track dust transport. It can ?? close to source, close to the dust event and it can track it during transport. And normally, for example, over the Atlantic, dust gets transported over about five days. MISR can see that dust over five days and say how the dust changes. And what we are able to establish right now with MISR looking at case studies is that dust doesn’t change very much. And it only changes when that air gets cold and dust falls down and mixes with other aerosols in the boundary layer that’s when properties change dramatically. MISR allowed us to actually study that.

BLAIR: When you talk about these storms, obviously, if there’s a big storm in a desert because that’s a good source of dust, do you look at that in advance and try to plan your missions accordingly to get in the thick of it, so to speak?

RICHARD: In some cases, yes, we try to look at forecasts. Instead of just looking at weather forecasts, which are important, because we need to know whether there’s going to be clouds around. But there are other specific forecasts that try to predict when these aerosols are going to be in a particular region or when they’re going to be generated. We do try to plan our research flights to try to look at episodes where the dust maybe higher, more of it or there may be something in particular that may be interacting with something else with clouds. We try to consult these different weather models as well as chemical transport models. They try to figure out specifically what kind of aerosols we’re looking at. And we try to tailor our flights to match up and see if we can evaluate how well these models predict that.

BLAIR: And which satellites do you use mostly in your studies?

RICHARD: You may have heard of the NASA A Train.

BLAIR: Of course, the A Train.


RICHARD: There are several satellites, like ?, MISR and CALIPSO. CALIPSO is one we work with a lot because it’s a LIDAR system, somewhat similar to what we fly here in this aircraft. They’re flying continuously using a laser to measure the amount and type of aerosols that we see. We actually fly a lot right underneath the CALIPSO tracks to provide data to help them assess whether their measurements are representing the dust correctly and give them some evaluation data.

BLAIR: You get the data but you can also help them calibrate their sensors as well.

RICHARD: That’s right. We try to help evaluate their data or provide them more information about the aerosols they’re seeing that helps them understand how to better analyze their data as well.

BLAIR: You’re looking at the dust in all kinds of ways, from the Sahara, from China, from sea salt and you’ve got all this stuff. How is all this data going to help us understand more about climate change?

RICHARD: What we try to do is work closely with the modeling community to figure out what are the greatest uncertainties in trying to predict the current impacts of aerosols on climate as well as their future impacts. Some of the biggest things they want to know are where are the aerosols located in the atmosphere? The models try to say are they close to the surface or are they farther away from the surface. The farther away they are from the surface, the larger distances they can travel and the longer times they can stay up. Our LIDAR data provides a very detailed measure of that.

FRANKLIN: When you track dust with MISR, it can also act as a predictor for health issues that might arise from dust events. Can you tell us a little bit more about that?

OLGA: Yes. Actually, I was involved in project called Maurice? project. The goal of this project was to link vast outbreaks of meningitis in the region. One theory was that dust is actually hard and dry plus it could carry viruses. A few papers actually show that after major dust outbreaks is related to outbreaks of meningitis. I participated in the project to use satellite data, model data and create a predictive system to provide early warning for the World Health Organization and for people to get a vaccination. It’s still a work in progress. I think that’s very interesting and it’s contribution to our understanding of how dust affects health.

BLAIR: What we need is some kind of industrial Pledge that we can apply to the atmosphere and wipe it away.

PAUL: Yeah, it would be nice to do that but we need dust too.

BLAIR: What would be an example of good dust?

PAUL: A really nice example of good dust, some of that dust that actually blows off of Africa will transport all the way across the Atlantic. Sometimes, depending on the season, will actually end up in the canopies of the Amazon rain forests. The Amazon rain forests, if you think about it, there’s not much dirt. The only place it’s going to get it is it’s got to come down from the sky. That’s actually part of the minerals that are needed there. Another benefit, if there’s not an overwhelming amount, but some of the iron content in that dust can trigger some plant growth and plankton growth which then is great for fisherman.

BLAIR: Like vitamin dust.

PAUL: Like vitamin dust. It’s a good way to think about it. But on the other hand, if you get too much, you get too much algae, then you get a red tide and that’s bad for everything. It’s kind of a mixed bag. It’s been there all the history of the Earth and we’re just now beginning to understand its importance. It has, just like anything, a good side and a bad side.

BLAIR: The most important thing is we need to know more about it and that’s what you guys are doing.

PAUL: And that’s what we’ve been doing. One of the projects the teachers worked on was how to use the Giovanni, which is developed by NASA. It’s a way to pull data down and look at what’s actually happening, taking the satellite data and trying to translate that into the classroom. That’s one of the things we’ll see the teachers, during the academic year, developing some problem based learning modules, some webcasts for the kids. They’re going to deal with data collected by NASA and begin to say, what does this mean? And what can we do? Because some of it is good, some of it is not so good but is there a way to find that right balance.

CHRIS: What’s your role in this particular workshop? Are you instructing teachers?

PAUL: Yes, but we have many, many brilliant scientists here. I take the information they’re giving the teachers and create some worthwhile classroom instruction that the kids can understand.

CHRIS: What do you hope the teachers will do when they get back into the classroom?

PAUL: We definitely want them to take that information into their class. We want them to give the students something practical where they can make a connection between all the high-level science stuff and bring it back home.

CHRIS: What are some the types of activities that you’re thinking of developing or in the process of developing for the teachers?

PAUL: In the beginning, because we are talking about dust and the affect it has on climate, one of the first activities was to insure that the teachers could distinguish between weather and climate. We did an activity this morning where the teachers created some nonlinguistic representations of both weather and climate. It’s an activity they can take into their classroom as well.

FRANKLIN: So this is a sunphotometer?

OLGA: Yes, this is a sunphotometer. I showed it to you yesterday.

FRANKLIN: Can I use it?

OLGA: Yeah, you can use it.


OLGA: You push the on button.

FRANKLIN: All right.

OLGA: You have to wait for a minute. Now you can open it and push scan. Now you point to the sun.

BLAIR: Hey, Franklin, look dust.

FRANKLIN: [sighs] All right, did I find it.

OLGA: Yeah, you found sun. Now, you wait.

BLAIR: Perfect for storms. You got that, Franklin?

OLGA: Okay, you’ve got data.

FRANKLIN: Okay, we’ve got data. Hey, you need to do it over this way.

BLAIR: Oh, all right, one dust storm coming up.

FRANKLIN: This is nice. We can take this data back and compare it to satellite data?

OLGA: Yeah.


BLAIR: Hey Franklin, is this far enough?

FRANKLIN: Farther. Don’t pay him any mind. He does this all the time.

OLGA: Okay.

BLAIR: Hey Franklin, far enough?

FRANKLIN: Go farther. Well, since we’ve got our data we can get on out of here. Let’s go.

OLGA: Okay.

BLAIR: And I guess Olga and Franklin got all the data they needed without my help.

BLAIR: Now, if I could only catch a ride back to NASA JPL.

[Car engine running]

BLAIR: I could help analyze the data. Well, until that happens, you’re watching NASA EDGE an inside and very outside look at all things NASA.

› Download Vodcast (362MB)