David Delene: Is our.
David Delene: Arms.
honestly.
David Delene: Welcome to Tuesday.
David Delene: may have a good Eastern.
David Delene: Yes.
David Delene: Easter.
David Delene: Egg.
David Delene: Egg on the third day.
David Delene: what's it about.
David Delene: chocolate.
Jesus.
David Delene: Okay.
David Delene: So I thought we would get to talking about radar day, so the current rate of damage and just to entertain do I went in my lab and and product couple things to look at for our radar system that I have to try to figure out what they are.
Max: So.
David Delene: As soon as possible.
David Delene: And groups and i'm going into the.
David Delene: table there so.
David Delene: And a.
David Delene: great idea my job and we're going to hopefully.
David Delene: Complete talking about radar.
David Delene: Day.
David Delene: And I got the chat up.
David Delene: People can hear me online with me know or chat I got my big mouse cursor here today, so.
David Delene: You can see the store moving up here.
David Delene: When I would have been a Klaus.
David Delene: and
David Delene: We are.
David Delene: supposed to have.
David Delene: His 19th.
David Delene: So next Thursday is our next exam, so I think it's going to be up to this week.
David Delene: and
David Delene: Try to give you another assignment on Thursday.
Okay.
David Delene: Okay, who is here on Thursday, can you remember, where we were we were talking about the different types of radars.
David Delene: yeah big thing that's yeah so that our sex bands, with the radars.
David Delene: And then the expand here but usually have.
David Delene: In the aircraft.
David Delene: So we got up to about here.
David Delene: So does anybody have any questions about radar and they uses a radar systems yeah.
David Delene: I uploaded a new version of the presentation.
David Delene: To the website, you can download.
David Delene: If I forget I got another question does anybody have been uploading the translations if I record the.
David Delene: zoom session to the cloud they do an automatic translation.
David Delene: Of what people say.
David Delene: But it doesn't seem to be the most accurate, because I have to talk clearer because it gets some of the words wrong is anybody ever look at that user think that would be useful.
David Delene: Okay, maybe check that out for me i've been putting it on the links with the.
David Delene: audio and.
David Delene: Video files.
David Delene: So let me know if that's useful otherwise or maybe stop doing that I don't know if it's useful to have that audio translation.
David Delene: And how good it is.
David Delene: So anybody have any idea what them or.
David Delene: What the big heavy one.
David Delene: For the show and tell today.
David Delene: Well yeah one says is an amplifier for what type of radar to catch me yeah so that's the type of data we have on prefer call.
David Delene: So the other one said some type of wave guide or splitter for a wave guides.
David Delene: So that's what would be inside of a.
David Delene: Wave guide, you have to both them together.
David Delene: So.
David Delene: We will continue if there's no questions comments.
David Delene: Questions about anything.
David Delene: So some terms terminology, we have targets and Eccles or to wait our terms, so targets are groups of objects that we affect greater energy.
David Delene: OK.
David Delene: And then, ECHO is the we affected rate of energy, so I got the widow similar say is coming back towards so especially fretted energy as opposed to what's transmitted and just go with out.
David Delene: So.
David Delene: You can use the echoes to have.
David Delene: A.
David Delene: To have a return.
David Delene: objects that are single objects.
David Delene: or multiple objects, they can rain.
David Delene: So what about.
David Delene: Aircraft we've heard about the stealth aircraft right, so you don't show up as much on the radar so anyway know how they do that was one of the secrets to making a stealth aircraft rain or.
David Delene: Material yeah one but what's The other thing sure.
David Delene: yeah it's how you do the angles and edges and stuff we're important as what I know it's so.
David Delene: i'm.
David Delene: So we want to talk about the amount of energy is echoed back or do we echo that we get speaker, because this is our detection of the objects.
David Delene: So what does that energy depend upon size number size and number of pockets composition of the target and distance we think of anything else, it might depend upon.
Their fears.
David Delene: And interference would be what's in the way.
David Delene: You know when we're talking about that at the end, which is kind of the attenuation you know what interferes with train.
David Delene: The ECHO coming back or to transmit energy going and all but the targets itself, I guess is this view first two targets, you know size of a target.
David Delene: Number composition and distance to the targets so we'll talk about each one of these in turn so size, this is pretty easy the bigger they are, the more effect bigger targets reflect more.
David Delene: um.
David Delene: And we are particularly interested in in Hydra meteors raindrops hail so and it's always this famous D to the six power.
David Delene: So what that means is that is very dependent on bigger sizes so it's not you return.
David Delene: You know if you get a doubling of the angles get a huge more return.
David Delene: Double of the diameter, you get a lot long term because it's a function not have diameter or damage to square one is damage to the six power.
David Delene: So the big drop is really turn a lot more.
David Delene: And that's my symbol here with the with a radar here with the domes sending out the energy hitting these targets and given an ECHO so smaller ECHO here and a larger ECHO.
David Delene: For the.
David Delene: Larger drop.
David Delene: The next is composition.
David Delene: Of the target, so we have again my radar and I have a goal.
David Delene: Before on here versus some water droplets so the water, where we turn more.
David Delene: With the ECHO returns here, then the snow So yes.
David Delene: Both.
David Delene: sides, so one big drop where.
David Delene: makes it a lot more than a lot of smalls so you really need a whole lot of them, so its size number of targets, the composition of targets and offer our way to targets are.
David Delene: But the size is is greatly important so.
David Delene: So if you double the size, you want low return that just have a few more targets.
David Delene: But the composition.
David Delene: is also important, but not as important as size, for example.
David Delene: So that's what's given here is, you know most effective to least reflect their so wet hair.
David Delene: would be most effective because it's a large target and, as we call it web because it be coated with water.
David Delene: So.
David Delene: Then you have rain because it's large you get some wet snow dry dry snow and ice crystals are the least effective.
David Delene: So we're looking at crystals that we turn off less energy.
David Delene: Why don't you be more.
David Delene: Because of well.
David Delene: The basics of it is.
David Delene: The kind of the refractive index the materials, basically, the way it works as a kind of absorb and we emit that energy.
David Delene: So it's not fundamentally, what happens on a very small scale, so you got to take that energy and transmitted back, and so the water has a higher refractive index then is it will reflect more um.
David Delene: It is this a property of the matter.
David Delene: In terms of them worker operators, yes.
sure.
David Delene: yeah It is because of the way that the atoms are, and I was doing some reading about this too it's like the objects.
David Delene: For some of the interactions with them because it's a lot of it happens on the surface, so it doesn't penetrate into the interior of the objects.
David Delene: So it's kind of like the objects, the energy goes around the Shell and kind of loops around the drop where it comes back and so with the ice crystals you really don't have a sabbatical nice conductive surface that you would have ice particles.
David Delene: Yes, so that's the difference, you know if you have water on it or wet snow so like the this last know store big breakthrough, Nice and wet compared to the dry.
David Delene: type of snow we get in January, or something so have enough water, and it was usually call it on the outside so called web snore went here.
David Delene: So that we fractal out more.
David Delene: On that and that coding doesn't have to be very thick.
David Delene: For that to happen so that's what we mean by wet hail snow is that it's coated with water.
David Delene: As various surface, not the.
David Delene: Not the interior doesn't penetrate in and it's not we're like a refractor it's more eco absorption and we transmission of the energy.
So it's.
David Delene: it's electromagnetic waves, so it doesn't really depend what way weeks, they are with their they come in so but that's assuming that the you know, in the same size so what's know what snow or drystone still have the same size is that really makes a lot more difference.
David Delene: But the composition, with two so.
David Delene: This remember water reflects more than ice.
Because of its composition.
David Delene: what's a good questions.
David Delene: um.
David Delene: The final one is distance to the target so send out the waves here if they're closer, they will reflect more back.
David Delene: Basically, more energy is get into the course of targets than the further ones, the energy has to spread out so, you said that beam all and it spreads.
David Delene: So if there are further away basically have less energy hitting your targets.
David Delene: So if they're closer they get more of a return.
David Delene: So rainbow effectively.
David Delene: And effect effectively as the mall of the actual that we mentioned when we get back.
David Delene: Usually the symbol for this is.
David Delene: BBC.
David Delene: And it's just the amount that is we turn at the sensor.
David Delene: You know, ECHO intensity or strength, the moment energy as we turn this is also we read it to Rachel Ray.
David Delene: and historically has been categorized and six different levels.
David Delene: With this Digital Video integrated processor.
David Delene: Basically, just characterize the amount of energy coming back.
David Delene: into different levels.
David Delene: very useful for working at middle article targets.
David Delene: So, think of these different levels kind of as of as an arbitrary value that someone gave it above a certain value so next slide here shows.
David Delene: What these levels are just numbering them.
David Delene: And then.
David Delene: You can kind of get a sense of.
David Delene: The reflectivity values again maybe going to BBC so it's a number and then.
David Delene: Look at their rainfall rate, so one of the things I remember is like 30 BBC when you look at your radar reflectivity values, you need about 30 db sea.
David Delene: level so that you have any rainfall if it's not up but 30 might have a lot of misc.
David Delene: or something, but you really don't have that even light green invests and then you can go off to 3536 get a higher margin rainfall.
David Delene: And then, of course, when you get to 5055 you get that heavy heavy rain.
David Delene: And so, if we do this in terms of rainfall, then we have the same composition.
David Delene: And approximately the same size, at least for 50 years.
David Delene: And then five times you also look at like 60 above 60 PVC might be an indication of this hell in the.
David Delene: store.
So.
David Delene: So kind of keep that, mind you know some of these numbers because you want to look at your returns and see you know, was it raining there is it snowing.
David Delene: Or are you just looking at a lot of clouds.
David Delene: So 30.
David Delene: And maybe 5052 effectively values.
David Delene: So light rain to very heavy rain.
David Delene: next thing we have talked about is the radiation and the speed of light, you know it's very fast.
David Delene: put this in meters per second.
David Delene: Number I remember it's three times 28 meters per second.
David Delene: You do it to a decimal point there and, of course, that makes a difference if you're in a vacuum of space or, if you have penetrated to.
David Delene: Material even the atmosphere.
David Delene: And so slows down speed of light so fastest in a vacuum, so one of the things with the wave guides that showed you when we do.
David Delene: The amount of.
David Delene: atmosphere in a wave guys, so we provide it, we also make sure that there's not a lot of water vapor that cases or.
David Delene: Four attenuate the signal.
David Delene: Because it depends on pressure temperature.
David Delene: Water vapor and.
David Delene: Give a the speed of right, if you think of.
David Delene: 1.00 is the speed of light in a vacuum, the name the atmosphere if it's a fraction of that so very close to it but it's very different.
David Delene: So the other thing is to consider.
David Delene: How the.
David Delene: Radiation travels in the atmosphere Okay, as opposed to.
David Delene: a straight line optics here we have this.
David Delene: Standard refractive condition, so we fraction is how the radiation bends so it changes from a straight line condition.
David Delene: And even illustrate this with this four thirds are this of how that radiation effects, so you want to find out what an object is.
David Delene: In the atmosphere you can't just assume it goes straight it actually does.
David Delene: riffraff.
David Delene: As it moves to the atmosphere so it's bent down.
David Delene: towards the surface.
David Delene: Actual gradient of the.
David Delene: You know, depends on temperature pressure humidity and these can all be calculated from if you saw any condition sound is of this vertical profiles of temperature humidity and pressure.
David Delene: And so you can do like a standard this standard reflection, but that can be have errors in it, so a lot of times that's what you do is you just say okay well what it's going to assume kind of standard atmosphere and get what it is, but there'll be some error to that.
David Delene: um.
David Delene: The other thing is, we can because of this error and some of the conditions, you can get super we fraction.
David Delene: get more of it coming down.
David Delene: To the surface, so this is important for like if you try to target or track an object.
David Delene: So that's called super reflection and it bends the radiation down towards the surface.
David Delene: And so the next one is.
David Delene: height of the radar of beam sort of bemis energy going out.
David Delene: as a function of distance, so what you do is you.
message.
David Delene: and sends out the signal.
David Delene: What height, so this is a this is range and miles, so what you typically do is you tilt your head up at different angles, like half a degree one degree above the horizon.
David Delene: Two three and so you get this till and that's how the radar operate they do, they look at one angle, and then it your scanner around, then they move up or do another one, so the actual radar returns that you get.
David Delene: On not just straight without a tilted angle.
David Delene: So.
David Delene: If you want them to actually get something at like 10 farmers, you have to work out a bunch of different tilting angles, and so you get one measurement here one here.
David Delene: So you have to look at a different tells independent how far away from the radar your.
David Delene: The other thing is raiders typically don't look straight up.
David Delene: So, having noticed when i've been showing you the the plots of our North Dakota radar area images, if you work this always this whole the different presets when we have the big snowstorms that's right above where the radar is.
David Delene: So the radios don't measure right above where they are.
David Delene: And then, as they go away.
David Delene: From the radar.
David Delene: You don't see the lower part of the atmosphere.
David Delene: So if you got some storms that i'm low you only see them when they come close to the radar.
David Delene: Because of this till so that's one of the things particularly go West we have waiters various spots in Pasco away from each other and snowstorms don't have followers that are very hot, so the raiders don't necessarily see them.
David Delene: So that's one reason why the north Dakota has their own radar and Bowman, is because the other radars and so far way they don't see them stones because of the social distance from the ground based readers.
David Delene: So question.
David Delene: So a lot of radars and have readers that like when 100 miles away you're working.
David Delene: In going to get distances to 300 miles away, but you missed that were part of the atmosphere, because the way that, let me fraction works.
David Delene: So targets.
David Delene: talked about this before, but he had clouds rain snow hail, and then we're going to talk about attenuation.
David Delene: So you can look at clouds you can work out rain.
David Delene: You could find the size distribution groups or teams to the on vacation.
David Delene: You know, get the rain rain, how much it's raining in the area.
David Delene: Look at the different levels of the reflectivity.
David Delene: And so, one of the things we do a lot is.
David Delene: Take.
David Delene: What we call Z our relationship so or as reflectivity.
David Delene: Sorry CSE for activity.
David Delene: Or is the rain rate.
David Delene: So we want a relationship between.
David Delene: What the reflectivity we get back is to what how fast it's raining.
David Delene: So there's no.
David Delene: direct way to derive this because that reflectivity depends upon.
David Delene: Size number of particles and so there's no unique relationship to how fast it's raining.
David Delene: But the distributions are pretty constant a lot of times at different storms, so we can have.
David Delene: A relationship, and then we have this what we call empirical You may know what empirical means and science.
David Delene: will be the opposite of pure evil.
David Delene: You heard the term before.
David Delene: It has to do aeration.
David Delene: So.
David Delene: If you read two variables two parameters right whatever it is, you know, in terms of you said mass and distance or something.
David Delene: So.
David Delene: You can have.
David Delene: What we would consider a theoretical relationship like.
David Delene: A ball or no hill you could theoretically use equations to predict that.
David Delene: i'm in physics of our time, so when empirical one says friction, you know how much energy you get from the different surfaces.
David Delene: So it's kind of out we don't understand everything that goes on underneath but we just kind of come up with a number that seems to work without understand all the details so empirical means measured it's a measured relationship.
David Delene: So what we basically do is we go measure the rainfall in area and see what the reflectivity is from the radar.
David Delene: So we can have a rain gauge measure it.
David Delene: And then we also measure that we for activity.
David Delene: And we just do a whole bunch of measurements and just reiterate the two and we don't know why they're you know the underlying.
David Delene: size and positions that are related but that's what we get so and we just come up with some type of relationship so one of the famous ones is the.
David Delene: Marshall Palmer relationship where you have the reflectivity goes 200 times rain rate to the 1.6 power, so these numbers 201.6 a kind of empirical fit Constance that just from a mansion.
David Delene: So you got to do this to a bunch of storms and you come up with this type of relationship.
David Delene: But this can depend on the type of storm, you have where it is, and you just change them around.
David Delene: So and that's where you can get.
David Delene: These relationships between the different levels and what the reflectivity values are.
David Delene: Between the rain rates and infertility.
David Delene: Someone should try to.
David Delene: Put in the.
David Delene: Rain way to Point one.
David Delene: And what Z value, you get out, I have a calculator.
David Delene: Take point one raises the 1.6 200.
David Delene: And then you get the.
29.
I shouldn't.
David Delene: Do that exponential on your radius.
David Delene: So it's like a square square there's not as much as squaring it.
David Delene: look at it, because you got to see.
David Delene: activity which is enough for units to because I mean, and this is logged in when it comes in there too.
David Delene: um.
David Delene: should check that.
David Delene: i'm.
David Delene: The last thing.
David Delene: To talk about.
David Delene: One another thing to talk about is attenuation of transmitted signal.
David Delene: So attenuation.
David Delene: Is.
David Delene: A reduction of the energy that goes out before hits a target.
David Delene: For a on the way back so it's what's it affair between the.
David Delene: sensor and your target.
David Delene: That kind of goes back to what's not a copy of your chocolate so atmosphere crowd rain snow hail.
David Delene: things in your hardware, they all can we do.
David Delene: The signal so it's all reduction.
David Delene: that's very tenuous 10s and reduces the energy.
David Delene: that's why I have this sign of soda wave that we do here.
David Delene: So we want to talk about each of these.
David Delene: out, you know types of attenuation started with happen spirit attenuation.
David Delene: So some gases cause know of what can you Asian Nigerian carbon dioxide have very small amounts of attenuation.
David Delene: But oxygenated particular water vapor can attenuate a walk a lot.
David Delene: so that we do says, the amount of.
David Delene: Energy.
David Delene: So next process by how much so on the y axis it's called the attenuation DVD so a lot of times you can get.
David Delene: You know 3040 we can be valued coming back it's called to way because it goes to the target and comes back for a distance, so if you're small close to the targets.
David Delene: Small attenuation.
David Delene: But as you get further away from the target attenuation gets bigger.
David Delene: Because, because you have more of an atmosphere.
David Delene: And then the other thing is that the attenuation.
David Delene: also depends on the wavelength.
David Delene: So one thing is that the sea ban attenuates more than the aspect.
David Delene: So dependent what frequency you use they can attenuate more or less.
So.
David Delene: So attenuation just going in through the atmosphere.
David Delene: Next, you have crowds.
David Delene: Calls can be made of water ice very thin very dense.
David Delene: And that attenuation depending on the temperature wavelength, and the amount and whether its water ice next fall so.
David Delene: So.
David Delene: It just depends again, you know on what what is there are you attenuate ever raindrops.
David Delene: brain and about driveway attenuation raindrops are much larger than crowd you're up with again it just goes by the size of the targets.
David Delene: When attenuates.
David Delene: is larger than crowds if you look at crowds and there's a range.
David Delene: between you and your target, you can reduce your signal so we're doing this in a study in 2015 is that we're working 6070 kilometers away, they seem to be a nice range chef in between.
David Delene: So we were worried about the attenuation the reduction of the properties there because we compared from what the rate of scenes to what we were trying to calculate directly from what was observing the crop.
David Delene: So that radar has a difference because it has to go through whatever in the middle.
David Delene: So they would have been chef here versus the.
David Delene: cloud particles.
David Delene: hail.
David Delene: I said before, attenuates.
David Delene: What exactly how much as part of measure.
David Delene: Because we do not have measurements of water ale quest on it to the radars.
David Delene: And then we hard to know where the kale is there, so.
David Delene: So they do attenuate but we don't really know how much.
David Delene: Is it would have to be appeared rematches.
David Delene: But we have this farmer called attenuation shadows.
David Delene: Where we can have a storm and you can see that it's reduced.
David Delene: airborne export raiders tip lot of times have shadows.
David Delene: For.
David Delene: attenuation.
David Delene: And I think we have an example here.
David Delene: So let's look at this kind of closely so i'm going to show a bunch of these setup older.
David Delene: Pictures of radars.
David Delene: So maybe someday this is 1989 I should maybe update these, but the principles of saying so on a lot of these you have wi fi activity values.
David Delene: On the X axis here with high ones, given a white and purple a high areas, right here, lower with red and blue, and then the green.
David Delene: Okay, and then this is the.
David Delene: velocity, so this is a docker velocity going away from work towards the radar so can someone tell me in this image where would your radar be okay.
David Delene: So it's the exact Center of the storm so it's right here, so this is the reflectivity.
David Delene: And so you can see a couple of things have this going here, and you have this mean area here but there's really nothing here.
David Delene: So, but there's green here, and we know around this.
David Delene: So why do you think this is what we have that shadow.
David Delene: So it's transmitted energy to the storm.
David Delene: And sometimes we threaten back, but not enough of it is penetrating through that heavy rain that heavy amount of targets so that you can illuminate stuff behind it.
David Delene: and get a return.
David Delene: So this is what we call shadow.
The image.
David Delene: So be careful, if there's a couple of storms one behind the other, you know we know what the other second storm would be.
David Delene: Okay, so any questions about any way she.
Is.
David Delene: Yes, so pressure high pressures would intend to eight more temperature again I think it's the higher temperatures with anyway more.
David Delene: But its fuel pressure.
David Delene: But you can have.
David Delene: Differences of the temperatures will make a difference to.
David Delene: For this, so.
David Delene: it's very a lot of times temperature differences and amount.
David Delene: Of the change.
David Delene: But pressure, of course, is more.
David Delene: You can hire attenuation with more pressure and then the concentration of gases, you know higher concentration of water vapor and wait for.
David Delene: I think in general is temperature ever attenuated yeah molecules are moving faster and more chance to accept that radiation.
David Delene: So.
David Delene: Anyway, he has his blockage of that that way that's going to war.
David Delene: attenuation questions they have to think of the concept, so you can understand that what you get with the returns, you know.
David Delene: If you're looking at a rate on your image or you're looking at it at the spray from a raid on an aircraft, you want to be with her, but.
David Delene: What it's showing you.
David Delene: So there's some problems with these.
David Delene: Okay, I want to try to keep going through this i'm being characteristics.
David Delene: What the beam is like how how wide it spreads out.
David Delene: So they all mean versus white beams.
David Delene: Long Range you know how far does have been travel.
David Delene: So the thing to remember here is that a target that fills the entire being will be taken.
David Delene: or illuminated more strongly and accurately, then when that does not so them nail beans versus white beans.
David Delene: were to compare them and in the wrong and struggling beings they kind of get this and this one we use like a aircraft, but notice radar sending out a a beam in front of the aircraft.
David Delene: You know, we want to see what's coming up in front of us as we're traveling.
David Delene: So, most of the time, want to avoid this, some of us like to go and find the targets to, but we want to see how 10 stay all before we get there.
David Delene: So here's a nail beam if we shot a nail been at the.
David Delene: At the target what you expect.
David Delene: And so what we have now is a have a display.
David Delene: So you have these range wins and using nautical miles 4550.
David Delene: So you have the reins and you just time and we sent out that paul's in his weight, but after we turn back, and we can tell the distance there.
David Delene: And then we can be spray spray.
David Delene: And we can have a target so once that target it's a little illuminated and it's above a certain return value we can paint it as a color.
David Delene: So, with the nail beam it fills it in a strong target back strong we.
David Delene: All like the same radar, this is the same radar same wavelength.
David Delene: Of think about this in terms of just like same type of radar on on an aircraft, so you really want to compare what you would be seeing from different ratios.
David Delene: Are certain retailers that were designed to shoot winder beach where Is this true for all.
David Delene: of you know, remember when we talked before about it, what what determines how much it spreads.
David Delene: Remember, we talked about.
David Delene: One feature of the radar was went through way back on Thursday we talked about the different components of the radar.
David Delene: So the dish remember the dish size, so if you got a big nose and you can put a big radar in there.
David Delene: You can get a smaller being.
David Delene: Okay, so.
David Delene: Bigger dishes better in a bigger.
David Delene: get a narrower being that you can paint the targets.
David Delene: But you know, as you said, when did you ask.
David Delene: This is one radar so we can't change the size of the fish or the size of the radar or type of radar.
David Delene: So now you're kind of stuck with one that you have an aircraft.
David Delene: So you say, like the Nairobi when it fills retirement will be repeated, is that, like we want that to happen, so that you get a better skin happening.
David Delene: Over exaggerated store well it kind of exaggerated my thing, but what we want.
David Delene: Is a target phil's entire bit being.
David Delene: will be painted more strongly and more accurately and one that does not.
David Delene: Okay, so a narrower.
David Delene: beam.
David Delene: is better, so it means a bigger dish.
David Delene: means bigger.
David Delene: But we were to set with what we have.
David Delene: been you know it's just like.
David Delene: figuring engines are better right.
David Delene: So.
David Delene: So narrow beam give us a stronger target if you have a wire beam with a smaller antenna.
David Delene: um what will happen another question.
Yes, sighs.
You explain it.
David Delene: You can you can move where you're scanning.
David Delene: But the beam size, you can be fixed by the radar.
David Delene: But antenna basically.
David Delene: So, or you can point at different ways the points in front of you, so it is a lot of times with.
David Delene: we're coming up to our target or something you know you can see, oh there's something off to your side or.
David Delene: You know, and then you can see how close it is you know if it's 2550 miles, all in all, fast to call it, OK, we get to this before that, so if you see a big.
David Delene: target in front of you may watch it for a while, so okay well I don't really want to go through this and then talk to, etc, can I deviate, for this is going on that's coming up.
David Delene: So we'll see this like when I was working in Florida we get audited convection a lot of times with the sea breeze and in the complexion person just inland at the coast.
David Delene: So on on days when you don't have these storms on these aircraft come down to a mammy they'll come down inland of the coast and then you get the stones develop any obvious gets shifted it would have been off shore.
David Delene: Right, so you could see this, they all want to go off shore.
David Delene: It so and then he would hate me when I try to if I go North and South, with the air traffic that's fine, but if I start going across all their fight pass, then it really messes them up right so.
David Delene: um but then move to avoid these particular because they just don't want to and it's just what a bit more distance that do don't fly off short of it, but if they have the choice right they just take the shortest distance to somebody in your way.
David Delene: So wider beam.
David Delene: That not failed as much so, you get a weaker ECHO.
David Delene: So if you compare the ECHO, you have more levels.
David Delene: Now it's weaker.
David Delene: Just because of the returns so.
David Delene: Again, this would be when you actually change the size of your radar.
David Delene: OK.
David Delene: The next thing that we look at is short and long range the short ones when it's posed by if he feels.
David Delene: The ECHO and you get a strong return, so this one's between 25 and 50 miles.
David Delene: Right, so we compare that to a oneness longer further way.
David Delene: You know you have your storm there it's longer range.
David Delene: Now, instead of being between 25 and 50 miles it's out there at 150 miles.
David Delene: Okay, so long range is not feel that, and you get a week to refer, so you can see, this and it will get stronger and stronger as you get closer to it.
David Delene: So get a big return fall away, you know it's very big store.
David Delene: So.
David Delene: So we get that.
David Delene: So this is where it would be the same way, or you know we just get closer to where we start pairing stronger that's why sometimes you might just take a distance and say oh we'll wait till it gets to about 50 miles.
David Delene: That point of time to decide to change.
David Delene: So the next thing to think about is being.
David Delene: smearing.
David Delene: Particularly at longer ranges you have two targets that are located, so that one's on the edge of the other or, at the same time, in a target of kind of smear together.
David Delene: You got actually two individual targets right and maybe.
David Delene: have two different storms next to each other when they're far away.
David Delene: They look like they're connected with smear together and you may want to just fly right through the middle, but what the.
David Delene: image and look like is instead of seeing the two targets, you would see want.
David Delene: So that's the same thing, like, how do you look at a store for any type of object, how do you distinguish two of them from one of them.
yeah.
David Delene: move away from it.
David Delene: easier to just.
David Delene: see what happens when the air traffic closer to the tower.
David Delene: She getting close to you can see that it takes on the shape, so instead of being out there hundred 50 miles.
David Delene: you wait to get to 50 miles, and you can get a CD to individual targets.
David Delene: to distinguish them.
David Delene: So that's the idea of having to target and smear them together.
David Delene: Okay.
it's questions.
David Delene: That.
David Delene: i'm talking a little bit about doppler radar is the car coherent, as opposed to a coherent.
David Delene: document, you can see the frequency shift, this is where you can see if the targets are moving towards you away from you and just a note that, due to this motion of target we have this what we call spectral with this is how much the the width between the different.
David Delene: peaks and gets compressed so you send out a pulse hits the target and that waves that come back changes so.
David Delene: that's another term you can hear sometimes people look at the spectrum with of the return signal.
For this.
David Delene: i'm so.
David Delene: Almost done.
David Delene: yeah I got another 11 slides that's the heart of the.
David Delene: The radar and we have a bunch of.
David Delene: Images of radar.
David Delene: To give you some examples of how to buy these concepts, so any questions on the concept.
David Delene: Okay.
David Delene: So.
David Delene: let's look at what we can get from various sources that you might encounter.
David Delene: and
David Delene: We again have the velocity.
David Delene: here.
David Delene: And the reflectivity so one of the things is the radar is always at the middle.
David Delene: Okay, and if you look at the velocity we can kind of see it is blue, and this is yellow so it changes once you pass to where the radar it's right, so if the store and winds are moving towards the radar once that gets applied a radar it's going to flip around.
David Delene: So you remember this velocity is relative to where we're located.
David Delene: Okay, we can't tell necessary anything more with just one radar.
David Delene: And then we have the reflectivity values here.
David Delene: and
David Delene: You can see this.
David Delene: wins I could kick off and give you some debris some dust that you can see it on the returns, we can even see what a box and stuff in the air.
David Delene: So you can get this returns and you can kind of see that does that movement here so much with the winds what the.
David Delene: The velocity values.
David Delene: So you see where's windy or not windy.
David Delene: um.
David Delene: So another example.
David Delene: Again velocity and reflectivity with the reds and Upper close with the higher refer activities, the White here highway for activity.
David Delene: And then the difference with the.
David Delene: reflectivity values.
David Delene: So here's a gust front.
David Delene: In terms of and then this one, you know you just have the section here so that's that's the observing velocity.
David Delene: So you have reds, then you have the blues So you see this line, right here, this would be an example about gosport.
David Delene: When you have these changes.
David Delene: Between.
David Delene: Nice.
David Delene: wins, that would be.
David Delene: going away.
David Delene: So, this would be like an example, the winds would be going away, but then you change it to going towards it.
David Delene: So you have these bigger.
David Delene: We effectively values, and when we can have the air come up and and why is in the storm, so you can have its air move in towards the storm.
David Delene: So one of the things I want to do this summer is try to get some balloons and mentioned turbulence in the velocity of this area going into starts with some.
David Delene: balloons into this door.
David Delene: So this is the.
David Delene: Oh, I forgot my I boy I.
David Delene: view so range height indicator, so I forgot my high so instead of the other one mean you're praying.
David Delene: We have north and south North would be up and you have the radar this would be like a.
David Delene: Wage hike so it's along the range of the radar and you know how how high it so it gives you the vertical structure.
David Delene: Of the data so.
David Delene: again.
David Delene: We activity values on the bottom was he's on the POP.
David Delene: And you can see, this transition with the blue line.
David Delene: Here, with the.
David Delene: With the.
David Delene: mean velocity.
David Delene: Where changes direction.
David Delene: Because you don't see that necessary in the reflectivity go use the correspond down here.
David Delene: But you see this change of direction.
David Delene: Have that i'm.
David Delene: So straight line winds, we have we effectively values we have this.
David Delene: One here, but you can see.
David Delene: way from storm you get these changes.
David Delene: From the blues to the orange.
David Delene: in the direction of the roster.
David Delene: So you can pick a lot of information about the winds.
David Delene: Again, another one with jive you were actually put in the eye.
David Delene: On these are trying to take too much time, you can take a closer look at these.
David Delene: and try to pick out the different colors and they're kind of not necessarily the sharpest is free, but this might be more what you get out of smaller radar system.
hoops.
David Delene: To put something on.
David Delene: The last couple of slides of my titan and the new version I got paid an hour always because ours is updated version of it when it is greater.
David Delene: ppi in parallel indicated each spray you know these are kind of what i've been shown at the beginning across as these titan.
David Delene: values, and this is actually the software that makes the images, so you can have the reflectivity values given in this color scale what high values here, and this one, I think, is you know you have the Montana border here, so you can see.
David Delene: Some of these sprayed, so this is what the meteorologist is looking at a lot of times, these two sprays, and then they can talk to the aircraft and say hey you need to go here watch this watch that.
David Delene: So they have these ways of looking at the data and they spraying it the other way is with your eyes, so this would be that.
David Delene: You know, high reflectivity values here with reds and yellows for this core of the storm, so you look at a cross section with distance seen it done distance and parameters.
David Delene: But you see the height here, you know you get up to 12 kilometers know up to 30,000 feet with somebody you get these cores darius obviously look at the usage rate on.
David Delene: The other thing they do a lot of times two is they use a forecast they watch how these storms, a move, and you can see them progress from one scan in another and then you can predict or this is going to move here.
David Delene: You can see how they're moving.
David Delene: With the main South so.
David Delene: We can have that make the prediction of the forecast.
David Delene: and
David Delene: So there's a couple of them, the difference between these two then to this is composite.
David Delene: reflectivity Okay, and these are the next one, is a quarter cappy so this one is that, like two kilometers.
David Delene: The composite.
David Delene: takes all the data and finds the highest value at that point throughout that layer
David Delene: Right, so they should pause it, but if you just want to look at one level.
David Delene: These cavities.
David Delene: And you make the display like that.
David Delene: And then, this is the final one.
David Delene: That we have for.
David Delene: how you can.
David Delene: You know, he gets sick of snow, we need one of these donuts cliff's notes everywhere around us step, where you are so that seems to happen.
David Delene: Okay, so there's more my knowledge about raiders.
David Delene: And we made it to my nice long continuous lecture finished.
David Delene: So thanks for your patience and I see you on Thursday.
David Delene: Any questions all right.
David Delene: Oh.