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Episode Five 205 – Weather (Earth Science)

>> Rick Crosslin: On the next earth science edition of Indiana Expeditions, we’ll be investigating Indiana weather. We’ll stop in to talk with Steve Bray from the Forecast 8 Weather Team. We’ll spend some time in the clouds. And we’ll take a look at some of the effects our climate can have on the planet itself. All in the name of earth science.

(Music)

>> Rick Crosslin: Try it yourself! Let’s go check it out. Come on!

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>> Announcer: Indiana Expeditions with Rick Crosslin is made possible through the generous support of the Dr. Laura Hare Charitable Trust: enhancing Indiana’s natural environment through preservation and protection of ecologically significant natural areas and promoting environmental education, stewardship, and awareness. The Center for Student Learning, Indiana Department of Education. And Veolia Water Indianapolis: As the operator of Indianapolis water, Veolia is dedicated to providing billions of gallons of clean, safe, drinking water to nearly one million customers in central Indiana every year.

>> Rick Crosslin: When you talk about weather, you’re really talking about water and the water cycle, because weather is influenced by the water that evaporates and goes up into the sky and then comes down, much like this water going up in the air. There’s an electric pump that pushes it up. But you might ask: What pushes the water up in the sky? It’s a much larger force. In fact, it’s the sun. The sun’s heat comes down, heats the water that’s in the lakes and streams and even in the forests, and it evaporates up into the sky. And then those small droplets of water vapor come together, and they condense, and they fall back as rain, snow, ice and other precipitation. In fact, that’s the whole cycle, and the power behind the cycle is the sun. Weather: it’s not that hard if you learn a little bit of science.

(Music)

>> Rick Crosslin: Today I got a weather break. I’m on top of the One America Tower in downtown Indianapolis. In fact, we’re pretty high up. We’re actually in the clouds. A cloud is nothing more than water vapor that is condensed into this big body of floating water up in the sky. And when they come together in just the right circumstances, they start to come down. Now actually some of those water drops will actually evaporate on their way down, but most of them hit the earth in a form of precipitation. Water vapor goes up into the sky, condenses into droplets, and falls back down. This process can take on many forms: rain, ice, hail, or even snow.

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These conditions can be very hazardous. Another aspect of the weather cycle is the air itself. Things can get really interesting when cold air from a cold front meets the warm air in a warm front. Our atmosphere is one big mixture of high and low pressure, hot and cold air, and it’s all mixing together. Sometimes it mixes together in just such a way that it starts to build with more and more energy, and we get a thunderstorm out of it. But occasionally, the cycle of warm air and cold air can become extreme and turn into something called a tornado, a very dangerous wind storm. A tornado can have winds rotating at speeds of up to 110 miles an hour. The United States has more tornadoes than any other country in the world. Tornadoes are definitely terrifying, and they cause a lot of damage. But there’s another form of extreme weather that causes even more damage: floods. When an area is faced with heavy precipitation, our waterways can become saturated. The result is the most dangerous weather phenomenon of all. The thing is that water will always go where it wants to, and it tends to take things with it, especially when it’s off its normal course.

>> Helicopter pilot: Three kids in there it looks like. They’re pretty much just going with it. They can’t control it. Get the rope over! Get the rope over! Throw it! Get it over! See if they can grab it.

>> Rick Crosslin: Thanks to first responders, these kids were rescued. They learned a hands-on lesson about the power of flooding.

In our world today, understanding the weather is very important. Weather scientists are always working to better understand and even predict weather conditions. But when faced with extreme weather, the best thing you can do is be prepared.

In Indiana, the weather may change everyday, but one thing it doesn’t change is scientists like my friend Steve Bray here at the Forecast 8 Weather Center. Steve, we’re here to learn about weather today.

>> Steve Bray: Great to see you. Great to see you.

>> Rick Crosslin: Well, I’m kind of new at this, but it looks like you have quite a bit of tools here, and your job basically is to keep us safe from weather.

>> Steve Bray: Yeah, using the technology that we have, it’s very important obviously to be safe here in central Indiana where we do get quite a few storms around and a lot of those tornadic storms and severe thunderstorms and even winter storms. And we use all the tools that we have to give people as much notice as possible to keep them safe.

>> Rick Crosslin: A scientist that studies weather is called a meteorologist, and they have their own special instruments.

>> Steve Bray: World War II technology gave us a radar that could pick up where it was raining and how big the raindrops were. And then eventually we got into color, and we were able to indicate by colors which were the bigger raindrops.

>> Rick Crosslin: Is that from the Doppler Effect?

>> Steve Bray: It is from the Doppler Effect. It’s like an ambulance that comes by you when you’re down the road. You hear the siren, and it sounds different coming toward you than it does going away. So using that technology or that theory, we apply it to radar, and so the frequency of a raindrop that’s falling towards you or moving towards you or moving away is different, and so the calculation of that can tell us which way the raindrops are moving.

With the ability to do mapping, everything from aerial photography to land/sat imagery and things like that, but just the technology of mapping. You know everybody’s gone to the computer and dialed up Google maps or some other form of mapping, Mapquest, to show where their house is or something along those lines. Well, with radar, we can plot that radar data on top of those maps and be able to show you on that street by street basis where we may be seeing something.

>> Rick Crosslin: Well, I’d like to see some of your radar in action here.

>> Steve Bray: You bet. You bet.

>> Rick Crosslin: Show us VIPER.

>> Steve Bray: Yeah, this is WISH-TV Forecast 8 VIPER. And what this is, is a computer system, display system that takes in radars from around the country, radars from right here in Indiana, satellite pictures, temperatures. We can display it all here. This is an example of that. What we’re showing is rainfall that’s going on in Illinois and just barely into southern Indiana. And we were talking about the mapping. We can use this to zoom in on these storms, show where it’s raining right now. We can actually tilt it, show where the rain is underneath it. We can actually put on the lightning too, which is obviously very important in these kinds of storms.

>> Rick Crosslin: A tool like this is pretty amazing technology when you think of the information, and how we almost take it for granted. This is space-age stuff right here.

>> Steve Bray: I’ve been doing this for a little over twenty years, and it’s amazing in that time span what we’ve come from. The displays that we can do now are what I once dreamed of being able to do. This kind of thing to where if there’s a storm in Indianapolis, I can zoom right down here to Indianapolis. If there’s a storm that’s out by the airport on the west side, we can zoom down here. We can show our land/sat imagery where we’re actually looking at what it looks like on the ground at that point.

>> Rick Crosslin: I always watch the loop, how the weather comes through here, and for me it almost lets me be a weatherman. I can see it coming and I make predictions. Oh, I see what’s going on here.

>> Steve Bray: It’s very important to be able to show the animation or the time lapse of the radar. Weather, in any kind of weather, satellites, radar, because you can really get a feel for the movement. And that’s one of the things that people want to know the most. When is it going to hit my house? So we can lapse this, and we can show you the motion of the rainfall to show which way it’s moving, and how it’s moving over time.

>> Rick Crosslin: So you’ve showed me some of the tools and science behind this. Now you have all this information in your head, Steve. How do you get it out to people?

>> Steve Bray: Well, this is where it gets fun, because this is one of the things that I like about it a lot is the ability for us to draw the graphics, put together the presentation of it to where we can show you where that hurricane is going to go, where this lightning storm is, things along those lines. But then we put it on TV and that’s the green screen. You want to try it?

>> Rick Crosslin: I’d like to try it.

>> Steve Bray: Let’s give it a go!

Alright, so Rick, this is the green screen. This is where we do the weather. It’s the magic of television. Because the TV screen that you see at home is the picture that I see here on the sides, and this green wall is blanked out by anything that has the map. So you only see the map, but it’s actually just a big, old green wall that I have to point to.

>> Rick Crosslin: Can I come in?

>> Steve Bray: Yeah, come on! Come on! Give it a try. What happened to your head?

>> Rick Crosslin: Well, I brought my green notebook, so this is something you probably don’t want to–

>> Steve Bray: That’s exactly right. If I had a green tie the same color as this book, the map would show up there. So that’s why we can’t wear anything that has the same green color as this wall. Some people think the map is somehow on the wall or we get used to a point, where this is Minnesota. But the maps change so much in where we’re looking and moving around the maps, but it’s not like that. You have to look at those side monitors or the monitor in front of you.

>> Rick Crosslin: Thanks, Steve. This has just been awesome, and you helped us a lot to learn more about weather.

>> Announcer: Did you know the Doppler Effect is named after Christian Doppler, an Austrian scientist? In 1842, he observed that the frequency of a noisy object changes as the object moves toward or away from you.

>> Rick Crosslin: Today, I have an alarm clock, and let’s see what it sounds like when it’s just standing still.

(Alarm clock rings with a steady frequency)

However, at the race track, those cars are moving around at tremendous speeds, and what does it sound like when an object that is moving makes sound? Let’s investigate.

(Frequency of alarm clock changes)

When an object makes noise and it’s not moving, you get a steady frequency. That same object, if it’s moving towards you, it comes towards you and the sound is also compressed, so you hear a higher pitch. As the object moves past you, it’s moving farther away, and the waves seem to be pulled out at a lower frequency.

Well, I’ll tell you one thing about Indiana weather: you just wait a while, and it will change. This is one of the deepest snows of the whole year which made a lot of kids happy and a few teachers happy, too. But this is a form of precipitation. And it’s a very unique form, because every little part, every little snowflake is a totally different design. Indiana has a temperate climate. We have everything from snow to rain to heat waves. Our weather changes a lot. And while that’s true, something bigger may be changing as well: our climate. But what is the difference between climate and weather? We caught up with Dr. Niyogi, the state climatologist at Purdue University, to find out a little more.

>> Dr. Dev Niyogi: Weather is something that you’re experiencing now. And today’s weather will become tomorrow’s climate. So one way we look at it is we have a period of say about thirty years or so that we use as a measure of what is going to be the climate of the region. What you’re seeing here is nearly 150 years of observations across the globe. So imagine that every observation that has been made across the globe has been averaged and you get one point for that one year. Every black dot you see is an average temperature for that year. And what you’re seeing here are a number of lines. This red line is the average trend that we’ve seen over the last 150 years. So it shows you that about 150 years back, our temperature on an average was somewhere around 13.5 degrees Celsius. But today, it is on an average 14.4 degrees Celsius. So it has increased about one degree Celsius. In fact, there is a well known phenomenon called the urban heat island. That means that the urban area is warmer than the surrounding non-urban area. Now when you have a larger area becoming warmer, there is a tremendous amount of heat that can be stored in that region. So we in fact now see for places like Indiana and central Indiana, places like Indianapolis, where if you have snowstorms or winter storms or any kind of storm moving over the Indianapolis region, as it approaches the Indianapolis region it starts splitting and goes around it. This could all lead to changes in our rainfall. It could lead to changes in where we have thunderstorms. Now thunderstorms are dangerous, but at the same time, they are very important, because they give us rain that we need.