Lab 10: Impact of Sea Level Rise on Coastal Communities

TIM BRALOWER: Hi students. So, today we're going to be talking about the sea-level lab, and how to manipulate files and get the data you need. In the first part of this lab, you're going to be looking at tide gauge data to look at recent sea-level rise, since about 1940 or so. And this is a KMZ file that you will load into Google Earth. And what I recommend you do, is you load it, and then basically it's very, very straightforward. What you're going to want to do is zoom in. So, I've loaded it, and now you can see my dots appear on my map. This is just the U.S.; the data are global, though. And you can see the dots appear on the map. The different colors are the time intervals. So, the last reported year is, in green, is 2016.

Generally, we don't tend to use the older sites which stop recording in 1998, etc. So, we're gonna be looking mostly at these green dots, and I'm gonna give you the name of a station in this state. So, you're gonna have to cruise around a little bit to look for them. So, let me just pull up one of these records that look at the east coast of Florida. Let's zoom in a little bit. Let's say we're gonna look at the east coast of Florida, and I'm gonna click on this guy here. You can see that there are two dots that show up. It doesn't really matter which one you choose. I always tend to choose the one that's in the ocean. If you see two dots that have different colors, you're gonna want to choose the most recent one. So, generally choose the green one. If there's like a yellow one and a green one, choose the green one and click on it. And then, it says Trident Pier, Port Canaveral. And I'm gonna click on the PS MSL ID number, and it's gonna open like a little web window here in Google Earth for you, and you're gonna see down here. This curve is what you want to be looking at. It's the monthly data in millimeters.

Okay, these are millimeters, so seven thousand millimeters, seventy-two fifty millimeters. This is a 250 millimeter difference. Which 250 millimeters is 25 centimeters. Okay, so you can see 25 centimeter difference from here to here. And you're gonna be looking at trends. So, in this case, you can see that the sea level is rising. It's kind of slow. You're gonna want to be looking at the middle of this these annual variations, which are to do with tides and all sorts of other phenomena. Alright. So, you're gonna want to look at the averages, and you can see that it's averaging rising from about 7,000 here in 1995, which is the beginning of your time series. And up here, it's averaging somewhere in the middle maybe, up here, just about 7200 or so. So, sea level is going up, as shown by this tide gauge data. So, you can be looking at a bunch of stations from different places and answering questions about what the trends are. Is sea level going up or down? Remember, this is relative sea level, so it is sea level relative to the coastline. And, in some cases, just to tell you, the sea level (relative sea level) is actually going down, which means the land surface is rising up.

So, this is kind of a cool lab because you're gonna be looking at very powerful data set, the tide gauge data. All right, so, that's that. It's pretty straightforward. So, I'm gonna get out of Google Earth. I'm gonna quit Google Earth. And now, I'm gonna keep looking at the sea-level rise data set, which is a really cool data set because it shows you flooding maps for what happens when we raise sea level. And the first thing I want to do is I want to change feet to meters. Unfortunately, it's underneath my recording button, so I'm not sure I can actually do that. But you're gonna want to change it to meters. This is a foot scale and if you click down here on the bottom, you'll see that it allows you to click on the knob, which I can't do, and change it to meters. Okay, so you will be working in meters. There are several things you can do. You can change that, you can raise sea level 2 feet, 3 feet, 4 feet. It doesn't show a whole lot till you move close. So, let's let's look at Houston, Texas. I'm going to zoom in on Houston. It’s a pretty low-lying area. It's not one of the ones we deal with though. Look at the coastline in Houston and you can see it's a really nice Google Earth Map. You can actually go up here, and you can look at base map Street View. So, in some cases, I'm having you look at Street View, in some cases I'm having you look at satellite view.

So, it's kind of cool. If you live in a coastal area, you can see the street you live on. And now, you can see what happens when I start raising sea level 5 feet, 6 feet. You'll see that not much is happening over here. But if we move up here, you can see there's a lot of flooding right in this part of Houston. You can see if I go back to one foot, two foot, three foot, four foot, you can see the progressive flooding. So, that's one thing that you're gonna want to look at in this lab. The other thing that's really cool in this lab, and I'm gonna go back to Street, and I want to move out. Let's move over here. This should be my…Why is it not letting me move out? There should be a scale over here. I'm not quite sure why it's not letting me move out. That should stay here, okay. So, actually, you know what I can do? I can enter an address. So. this is a cool thing. I actually have you do this. So, Miami, Florida. Actually, let’s not go to Miami because that scenario you're gonna be dealing with. Let's go to another coastal city. Let's look at a flat coastal. Let’s go to Mobile Alabama. Mobile, Alabama and now it’s going to take me there. Okay, so here we are, Mobile. Obviously, very low-lying and there's five foot of sea level rise in Mobile. Go back down again, three foot, you can see the water goes out, but, boy, it's flooded this area pretty well. I'm gonna go back out to satellite view.

And what you can look at on the left side here, is you can look at flood frequency, which would give you an area in red. Very similar to that other map showing you how frequently that area floods. But you'll also notice areas around these creeks are flooding a lot as well in red. So, that's the flood frequency. And the other thing we have you look at is this vulnerability map, which I find really interesting. And you look at the vulnerability map, and it tells you a lot. So, there's not a lot of construction here, so that's why that's not that vulnerable. But if you look at Mobile, most vulnerable is in red and least vulnerable is in pink. And you can tell differences between different areas in terms of their vulnerability. What it means is the vulnerability is not just the susceptibility of an area to sea level rise, but it's also how vulnerable the population is. So, for example, if you're looking at the inner city where there's a lot of poor people who can't adapt to sea level because they don't have the resources, that's going to be an area that's more vulnerable to sea level rise, than if you're looking at downtown Manhattan where everybody's millionaires. Okay, and so that's just an example. This is sort of a sociological side of sea level change that I find so interesting, and I hope you will too. So, you're going to be looking at a combination of the sea level rise view, you're going to be looking at the flood frequency view, and you're also going to be looking at this vulnerability view. And to move around from area to area because… Oh yeah, here it is. Look at this, there it is. I just lost it. I'm thinking I'm in Google Earth, but here it is, down here. Just enter these addresses where you want a tool around to. So, enjoy yourselves. I think it's a lot of fun. It's a really interesting lab, and you can tell I'm really enthusiastic about it. So, I will talk to you later on.

TIM BRALOWER: Good morning, students. The lab is now up and running and I would like you to watch this video in addition to the first part of the other video on tide gages. Unfortunately, what happened is that NOAA changed their sea level rise viewer. So it doesn't perform now some of the functions that we used in the current in the previous version of the lab that one of these functions was the vulnerability of communities to sea level rise. And the vulnerability is a function of race and income.

And NOAA has unfortunately taken this off, which is a real shame. Okay, so what I'm going to do now is I'm going to demonstrate the functions that you will need to use in the second part of the lab. And so what I'm going to do now is you can enter a search for an area and let's look at Houston. Galveston. Galveston.

Galveston. Galveston, Texas. Okay, so I'm going to go to Galveston and what I'm going to do is show you a few things. Now, first of all, down here is the slider for sea level rise. You're going to need to use this.

And I like to convert this to meters. So I slide this over and why isn't it doing it? There we go. So this is in meters. So what you can do now is you can look at the flooding of coastal Texas as we raise sea level.

So you can go up and you can see the blue coming in there. That's the flooding. So you can see it flooding over here, flooding over here. As you raise sea level, go up to three meters, basically the whole of Galveston island and the whole of this marshy area on the mainland flood. So that's the first thing you need to do.

Be able to play with this slider. That's the first thing. There are several questions that are based on how much sea level rises and what floods and again in meters. Okay, so that's the first thing you need to do. Please always use this search bar.

When I mentioned different places in Miami and New York City in the graded lab, please always use this search bar to look for these places instead of searching forever. The other thing that you can do here, which I have you do in the lab, is to use the street view. So you click on this. Whoops. Not this and not that.

Street view. So you can actually put on the street view, so you can actually look for street locations. And we can zoom in using this button here so you can see detailed street views. And then like for example, if you raise sea level, you can see this area begin to flood. It's a really really cool tool.

I'm really glad they preserved at least some of it for you to play with and hopefully use down the down the road. Because if you're looking to ever, like buy a beachfront property, for example, you can use the sea level rise slide viewer to see what happens to your property over the next few decades as sea level rises. Okay, so the second function we're going to look at here is these local scenarios. And this is what happens as we raise sea level under different emissions scenarios. So, okay, so I'll show you what you're going to be doing with this.

So you click on one of these symbols here, and this is Galveston, Texas. Okay. In the year 2050 in this case. But what I want you to do is view by scenario. So click on this view by scenario and this gives you these different sort of emission scenario, low emissions, meaning low sea level rise to high emissions, meaning high sea level rise.

Okay, so what we do here is we look at these scenarios and we might want to just zoom in a little bit to this part of the island. Okay, so this is this location and what happens is you go to the high emissions scenario, for example, and it shows you in 2020, it's going to be 0.19 meters. In 2100 it's going to be 2.5 meters. So to see what happens under the high emissions scenario, you're going to take the slider and go all the way up to here. And that's what happens under the high emission scenario.

In 2100, you go 2.5. I can't quite get that slider at 2.5. It's not letting me do that. But anyway, you can see my point at 2.5 in this case, 2.6 meters of sea level rise, much of the island floods. If we go to the intermediate low emission scenario, then the 2100 would only be 1.05 meters of sea level rise and only this tip of the island floods.

So that is how to use the local scenario. And that's the second thing you will be doing in this lab is the local scenario. Okay, so just make sure that when I ask you what happens in the intermediate high scenario, for example, in 2080, you raise it to here and you can see 1.4 meters of sea level rise. It's starting to flood. Okay, so that's the second thing.

It's very straightforward so long as you're comfortable with these controls and there are questions in the practice lab which allow you to gain that comfort. Okay, Then the third thing you're going to use is what we're looking at is high tide flooding and that is today. Okay. These are parts of the coast which flood today at high tides. And remember in this lab, in this module, we've been talking about king tides and high tide flooding in places like Miami and Charleston, South Carolina and even New York City.

So here we are in Galveston and you can see in high tides you have flooding in these areas. Quite a lot of flooding in Galveston today at high tides, which is really, really important. So what I have you do in these questions is look at individual places and see which places flood at high tides today and which places don't flood at high tides today. Very straightforward. So again, you're going to have, you're going to be looking at sea level rise with the slider.

You're going to be looking at these local scenarios where you click on a symbol or a symbol here. These are different locations in Galveston. And then the third thing you're going to be doing is looking at high tidal flooding. And you should be good to go with the second part of the lab. Again, make sure you watch that first video for the first part of the lab, and we will get this up and running and let me know if you have any questions and good luck.