 Hello everybody, and I hope you're enjoying Super Science Saturday, so the next, our next demo is called What's Up with the Weather, and in it I'll be talking about upward moving air in the atmosphere, so with that we can go ahead and roll the video. Hello everybody, and welcome to the demo What's Up with the Weather. I'm Christina Kalb, and I'm a scientist at NCAR. I've been there since 2009, and I've been part of the Weather Wizard since 2018. My area of research is thunderstorms, lightning, and computer weather models. Today, we're going to talk about upward moving air in the atmosphere, why it's important, and some of the reasons how it's caused. To do that, I need to bring in my assistant, Wizard Brian Vander Wynne. Brian also works at NCAR, and he works in the computer division, so he helps us set up programs and helps install software that we need to do our work. So, let's talk about upward moving air. Why is it important? Well, our air has a number of different molecules floating around. Some of them are water, some of them are other materials. And when we get upward moving air, and those water molecules turn to either a liquid, like the water that you drink, or a solid, such as ice, it forms clouds that we see, or precipitation. So, how do we get upward moving air in the atmosphere? Well, one way is that we can just have something at the surface pushing the air upward, or forcing the air upward, such as a weather front or a mountain. To demonstrate this, we are going to have our leaf blower here, and then we're going to see if we can suspend some ping pong balls in the upward moving air of the leaf blower. I'm going to turn this over to my assistant, ping pong ball, upward moving air. Ping pong balls move upward until they move outside of the upward flowing air, and then they fall back down to the leaf blower. Flows this air upwards, but it doesn't just disappear into space. It comes back down outside of the stream forming circulation. So, what happens if we try to lift something that's too heavy, such as the tennis ball? Too heavy for the upward flowing motion, so it fell out or wasn't able to be suspended. This is one of the ways rain can come down. How heavy does something have to be before it falls out? Well, it depends on how strong your upward moving air is. How is the ping pong ball suspended in the air? Well, Bernoulli's principle states that faster moving air exerts less pressure, and so when we put the ping pong ball in the upward moving air, it's suspended upwards. This slide shows an example of what happens when air flows upward from the leaf blower to the ping pong ball. You can see the red and blue arrows bounded by vertical lines. As air flows upward from the leaf blower, it can't go through the ping pong ball so it's deflected around, causing it to speed up. This creates low pressure immediately adjacent to the ping pong ball. In the atmosphere, low pressure is associated with clouds and precipitation. We just saw what happens when we use a leaf blower to suspend balls, but now what about a different type of object, such as toilet paper? What happens when we blow from below? The toilet paper goes up, but now we blow on top. You'll notice that this causes the toilet paper to lift upwards as well, and in this case, faster moving air horizontally across the top of the toilet paper creates low pressure, which causes it to rise. This is the same way in which airplanes get their lift and are able to fly up into the sky to take you various different places. So let's try blowing the toilet paper with a much stronger tumor there coming from the leaf blower. To do this, I need my super special magic rod placing this toilet paper on the rod so that it stays in place while the air is moving towards it. I'm going to start by placing this below the airflow in much the same way that I just did while blowing on it, and then moving it around slightly so you can see the effects of changing the orientation. Alright, Ryan, are you ready? We just saw that air moving upwards from the surface creates the clouds and thunderstorms and rising motion in our atmosphere, and also something faster moving that's over the top creates lower pressure above and we get rising motion. So I hope you enjoyed this what's up with the weather demo here Super Science Saturday. The next one is infrared is out there starting at 230. And I would like to give a special thanks to my assistant who has helped demonstrate upward moving air. Hey Tina, that was awesome to see. What a fun experiment. Thanks. We can take some questions that are starting to come in in just a second. And one thing that I was thinking of when I was watching this is that this is something that kids could try at home right if they have a leaf blower or maybe even do you think it would work with like a hair dryer. I would you just would probably need a smaller ball or, you know, even like a beach ball looks, looks larger but because it's filled with Eric can be lighter. And so that would be another thing that a lot of people may have at home that they could try themselves. Cool that might be fun of course people have toilet paper to although we may be having a shortage so be careful with your toilet paper. We actually have an interesting question that has come in about low and high pressure. Why do we need low pressure and high pressure to lift things up. So high pressure is generally not associated with lifting things up it's usually sinking motion in the atmosphere so it's the reverse and in this case you can think of higher pressure as being, you know, more dense or a lot more molecules at the surface. So the air tends to flow from high pressure to low pressure, and it doesn't just disappear off into space. So the low pressure is generally associated with the rising motion, as it flows from the sinking motion with high pressure. Okay, great thank you. There's another question. How come all of the toilet paper came off Griffin is wondering. If I hadn't locked it down on the rod, then the thing would have just blown the toilet paper off into off however far it went so it came off because I held it I held the role in place. And then the air pressure blowing at it causes it to unwind itself. It was almost kind of pushing the role to unwind huh. Exactly what I was doing like when you take your hand and you go like this but in that case you're pulling, whereas in this case, you know it's like if you put your hand on the back of the roll and go like this it's going to, it's going to unroll itself and so it's it's the pressure of the air flowing. So this makes me think of something Tina, I don't, I don't know how many of the folks that are joining us right now have joined us for the last couple but air pressure has come up, especially as Jeff was talking about extreme cloud formation. What is air pressure, what do changes in pressure have to do with weather or with clouds. So changes in pressure, low pressure is generally like I said earlier in the video associated with clouds and thunderstorms, but low pressure also tends to be associated with weather fronts, and you get different kind of clouds around different fronts. So a warm front tends to be more your flat kind of stratus based clouds in and to high sea risk whereas your cold front tends to be cumulus more clouds that are more developed they're taller in the vertical and longer. And so the cold front is usually stronger precipitation whereas the warm front is kind of more light rain like your drizzle type of precipitation. Okay, so it makes a lot of difference. And here's another question about high versus low pressure to planes fly differently in high pressure versus low pressure. So I don't know the answer to this because I have never flown a plane, but what I can say is the majority of the time the plane is in the upper atmosphere where the pressure is always just less. Really it would really be only during like landing and take off where differences in surface pressure affect the plane. But certainly the jet stream and the faster moving air above can affect the time it takes to fly somewhere. So yeah. Definitely. Danny has a couple things. Danny mentions just this is a really cool experiment. So you should try it at home to Danny. You mentioned drizzle and Danny's wondering what is drizzle. So drizzle is very light rain. When you kind of think of, you know, it's just kind of almost a mist, but it's a little bit more than a mist. That's that's what your drizzle is. Right now we don't seem to have any more questions. We'll give it another minute in case anybody wants to enter in any more questions. I have a question for you in general. Tina, how did you get into this kind of research the stuff that you study? What did you do in school? So I went to school for atmospheric science that was my degree, both my undergrad and my master's degree, and, and then I went into research after school. So atmospheric science, some places call it like meteorology program, but mine was specifically atmospheric science. Okay, interesting because we had Mike Nelson on earlier and he's a meteorologist. It's all really great, but it's all related and oftentimes what they say is atmospheric sciences is a little bit more broad, whereas meteorology is a little bit more focused just on the weather aspect of it. Although in my field, it's, it's pretty much the same. Great. And speaking of that, Danny is now wondering how many years did you study? Well, so I went to college in four, I went to college for four years and then I was in grad school for two and a half. So that's, I have six and a half years. It's a good number of years. One more question has come in while we're chatting. Nigel's wondering how is mist created. So mist is, is, can be often just thought of as like the same thing as precipitation. Well, I guess it depends on what you're referring to as mist, whether it's light precipitation or some people refer to mist as like spray off a sea. And they're, they would be created in different ways, but mist in the atmosphere is, you know, similar to precipitation, it's just a smaller particle. And just like fog is a cloud, but it's a cloud at the ground. And so mist just tends to be associated with lower clouds and very, very small rain droplets. So not a lot of upward motion. Great. It's cool. We've learned a lot about all different kinds of clouds in the last few presentations. That's been super fun. Well, it doesn't look like we have any more questions. So I'd like to just say thanks so much Tina for joining us today and, and sharing your fun experiment and I hope some of the folks who watched can go out in your yard they're on your streets, safely. A hair dryer might work. Yeah, I'll be curious. Maybe I'll try it with a hair dryer too. Yeah. Well thanks so much for joining us and thanks everybody for joining us for this session, and we are going to have another one coming up at 230 about infrared heat and radiation. So join us back then we're going to take a short break and thanks for thanks for coming today.