SciTech Now Episode 305

In this episode of SciTech Now, solar power at the famous Daytona International Speedway; the physics of ketchup; a proposed tax on carbon, a surprising discovery of over 600 miles of coral reef; and using fire to learn about the declining giant oak population in North Carolina.


Coming up... Racing towards renewable energy.

For us to have actually solar power on the property, I think that's just another commitment that we're trying to do things a little bit different than in years past.

The physics of helping ketchup hurry up.

Yield stress means that it needs a force in order for it to move.


And the thixotropic means that it has a memory.

A tropical reef at the mouth of the Amazon River.

I mean, we're all hanging over the side, and he's bringing this thing up, and, oh, my gosh.

He brings up this huge collection of very colorful, beautiful animals.

And we were just really amazed.

And finally, starting fires in service of science.

Prior to the burn and then again after the burn, our research technicians come in and do a sample of the overstory, as well as the understory or regeneration layer.

It's all ahead.

Funding for this program is made possible by... The Corporation for Public Broadcasting.

Sue and Edgar Wachenheim III.

And contributions to this station.

Hello. I'm Hari Sreenivasan.

Welcome to 'SciTech Now,' our weekly program bringing you the latest breakthroughs in science, technology, and innovation.

Let's get started.

The famous Daytona International Speedway in Florida is home to more than 7,000 solar panels, creating energy for the community and an educational opportunity for people to learn about clean solar power.

Here's the story.

Say 'Auto racing,' and several things come to mind -- loud engines, fast cars, big crowds.

'Renewable energy,' on the other hand, is not a term usually associated with the sport.

But at the Daytona International Speedway, home of the iconic Daytona 500 NASCAR Race, a recent renovation included an innovative installation.

Behind us is the Solar Pavilion.

It'll make us the fifth-largest solar panel install among sport stadiums across the country.

7,000 solar panels here at the pavilion, inside the track, and then on the back of the track, as well.

This is enough power for about 400 homes.

Solar power has a bright future.

No pun intended.

Technology has gotten better.

The prices have come down.

This produces no emissions, uses no water.

It's a terrific technology to have as part of a portfolio.

This will serve the track very well during the day when the track is operating.

And the rest of the time during the year, when the track is not in full operations and stands aren't packed, this will go in and actually serve all of FPL's customers' homes and businesses and help them with being efficient and affordable.

Besides generating clean energy, the installation will also serve other purposes.

For one, it gives the speedway a chance to show another side of racing.

When people think about motorsports, they think about gasoline and they think about all those elements.

But for us to have actually solar power on the property, I think that's just another commitment that we're trying to do things a little bit different than in years past.

It also presents an opportunity to educate fans.

What's unique about this is that we've actually put the solar panel pavilion in a place that's really is accessible to our fans.

There's going to be educational material below the solar panels in the pavilion.

And we're going to take the opportunity to give people more information about what are the benefits of solar power and what are the challenges, 'cause it's important to know the pros, the cons, what works, what doesn't work.

These solar panels will provide clean electricity for years to come.

And hopefully, this installation will be generating an even more valuable commodity in future years.

We now have an opportunity here to reach out and touch fans and, really, the children that come with them.

This is such a family-friendly sport, and to have an opportunity for kids to come in here, to see how solar works, to learn about it...

Car number 2 takes the lead.

Hopefully, it'll spark their imagination.

They'll see why it's important to get a great education, to focus on STEM, and to make sure they get mathematics, engineering, you know, science, technology, engineering, mathematics, to study those hard, and then they can go out and, frankly, change the world, make a difference day in and day out.

Ainissa Ramirez is a scientist, author, and self-proclaimed science evangelist.

She's calling for big changes in science education and is a creator of a podcast series called 'Science Underground.'

Here to discuss one of her latest podcast episodes, called 'Helping Ketchup Hurry Up,' is Ainissa Ramirez.


So, yeah.

The science of ketchup.


[ Laughs ]

It takes so long to come out of the bottle, right?

I mean, they've even had songs, like 'Anticipation.'

Why does it take so long?

Well, if we understand what makes up the ketchup, we'll know why.

Ketchup is made of vinegar, sugar, spices, and pulverized tomato pieces.

And they can't get past each other, so they need help.

And the way that we can help it is the first thing we can do is we can shake it up.

Right. Everybody does that.

Everybody does that, but the other thing we can do is that we can force it.

So if we get the ketchup, put it at 45 degrees, and use our hand and do this chopping form, comes right out.

I've always heard -- hit at a 45 on the 57.

On the 57 -- That's right.

And the reason why we do that, the science behind it is because ketchup is what they call a yield stress thixotropic fluid.

Wow, that sounds so nerdy.

[ Laughs ] And all that means is that yield stress means that it needs a force in order for it to move.

And the thixotropic means that it has a memory.

The particles are arranged in a random way.

And if someone uses it and another person uses it, it will be easier for the second person, because they're no longer in that random structure.

They kind of are able to flow past each other, like a school of fish.

So, really, they did do the work for you.

They did do the work for you.

[ Laughs ]

Always be the second person when you get the ketchup bottle, and it will flow right out.

What are other fluids like this?

So, thixotropic materials are kind of rare.

Like, the ink inside of a space pen is thixotropic.

It's solid, and then it's a fluid.

But yield stress materials -- Mayonnaise is a yield stress material.

If you get mayonnaise and you scoop it out, you put it in the refrigerator, you come back, that scoop is still there.

If it were a liquid, like honey, it would flow, it would recover.

You would never see that divot.

But mayonnaise, you see that scoop, and it'll stay there for a long time.

So there are other materials -- and blood is also a yield stress material.

How do they think about this kind of effect and this kind of -- just, really, the science behind this when you think about medical research or when you think about any kind of scientific research?

Well, actually, it's still very much an open question about how ketchup behaves.

There are a lot of mathematicians still working on it -- how the particles, the tomato particles, are being moved.

But if they can figure it out, it gives us a better way to process foods -- like, large-scale vats of foods.

How do we make sure that it moves through nozzles in a uniform way?

Also, it could be used to control if we have an oil spill.

If we have special, smart liquids that can thicken in certain ways, we can control where these spills go.

So that's why scientists are working on these crazy yield stress thixotropic materials.

What's happening on a granular level?

I mean, if we took a microscope or even something more powerful, how would we see all these chunks of tomato and vinegar and whatever else -- the special 57 ingredients in there?

[ Both laugh ]

57 varieties.

Well, the tomato pieces are randomly arranged.

They're all over the place.

And if I -- When I shake it, the tomato pieces elongate a little bit, but then they also form this kind of channel, if you will, where they all kind of are in one direction.

So when I turn it over and hit them, then they all can go in this place where it's easier for them to flow.

So, the tomato pieces are randomly arranged, and then by moving it, by shaking it, we give them some kind of order.

And that helps it moving -- to move out of the bottle.

And I'm assuming the difference between this and one of those red things that you see in every restaurant is that there's air pressure inside, and when we squeeze, shove it out.

The reason why it's hard to get a glass bottle of ketchup is that people -- They hardly manufacture these things.

You can only see them in restaurants.

It's because when they switched to the squeeze bottles, the sale of ketchup went up tremendously, 'cause people are really sick of waiting for ketchup to come out.

But when you squeeze it, you can totally control how it comes out.

All right, Ainissa Ramirez.

The science of ketchup explained.

Thank you.


Washington State has proposed a tax on carbon emissions for both residents and big business, following the lead of roughly 20 countries worldwide already taxing citizens on their carbon footprint.

British Columbia has seen a 13% decrease in fossil fuel consumption since their tax took effect.

Next, we take a look at the Washington proposal, including alternative energy options.

[ Chicken cheeps ]

This is Sally.

She's like most chickens her age.

She'll grow up in a place like this.

And that means Sally's hiding something -- a carbon footprint.

[ Roosters crow ] Sally's farm uses electricity from a coal-fired power plant, her farmer drives a diesel pickup, and her feed comes from a factory that consumes its own electricity and fuel.

Now meet Colin.

Colin was raised on a solar-powered farm eating locally sourced feed.

Today, raising Colin is more expensive than raising Sally, because carbon-free energy is currently more expensive than fossil fuels.

But someday soon, Sally's carbon footprint could tip the scales.


If we want to keep a livable climate, we have to put way less carbon dioxide into the atmosphere.

You've got two basic options.

You could make a law that limits how much fossil fuels a person or company can burn and penalize them if they break the law.

Sort of like a speeding ticket.

Laws like that aren't always popular, though.

That's where the second option comes in -- putting a price on carbon emissions.

Right now, you can put as much carbon dioxide into the air as you like without paying a dime.

But what if people had to pay?

Almost 20 countries around the world have adopted a carbon tax.

Here's how it works -- Companies pay a tax when they buy fossil fuels, like coal or natural gas.

The price is based on how much carbon is in the fuel.

And then they try to pass those costs on to customers.

That means with a carbon tax, the cost of raising Sally goes up.

And ultimately, when it's time for Sally to go to the great chicken afterlife... should be easier for consumers to pick Colin for dinner.

But a carbon tax isn't the only way to make carbon more expensive.

Enter cap and trade.

A bunch of countries have tried this, too, and so has California.

Under cap and trade, Sally's farmer can put as much carbon into the air as he wants, but if it goes above a certain amount -- the cap -- he'll need a permit.

The government only hands out so many of these permits.

So if you don't have enough permits for all the carbon you want to put in the air, you can buy or trade for them.

Cap and trade supporters say the law gives us more control over emissions.

With a carbon tax, we don't know what exactly will happen to emissions, but we have a better idea how much it will cost to try to curb them.

Either way, both laws ultimately make carbon more expensive to emit, with the hope that people and companies will change their buying habits.

So, how much more will Sally ultimately cost?

It all depends on the details, like where Sally left her carbon footprint.

In Mexico, burning carbon costs an extra dollar a ton.

In California, that same ton costs $13, and in Sweden, $130.

In any case, the more pricy we make carbon, the more competitive solar, wind, and other non-carbon-based energy sources become.

The question is, who's willing to stomach the cost?

A team of Brazilian and American researchers recently discovered 600 miles of coral reef at the muddy mouth of the Amazon River, calling into question the belief that these reefs need clear water to thrive.

Reporter Andrea Vasquez catches up with the expedition's lead American scientist, Patricia Yager, via Google Hangout.

Patricia Yager, thanks for joining us.

Thanks, Andrea.

It's nice to be here.

So, you did not set out to find this specifically when you went to the Amazon to do research.

So what did you find and how?

That's a really good point to start with.

So, this is a good illustration of the serendipity of science.

We went to study the Amazon River plume, which is a very large effect on the tropical ocean, and we needed to get to the mouth of the river.

And one of the scientists that came on board that cruise, his name is Rodrigo Moura.

I asked him what he wanted to do on this cruise, knowing that it was so muddy, and he handed me a paper from the 1970s, and it suggested in this paper that you could find reef fish on this part of the continental shelf of Brazil, and I kind of looked at him funny.

It was a hand-drawn map.

It's a very old paper from a kind of obscure journal.

And I looked at it, and I was like, 'Huh. Wow.

That would be really cool.'

[ Both laugh ] So, how do we do this?

And he thought that he could find them using the multibeam, which is a sonar-type instrument that's on the ship.

So he was watching the multibeam the whole time as we sailed over the shelf.

And he thought he saw things that might indicate the reefs were there, so he knew where we might want to go back to.

What do you know? He found them.

The multibeam is really high-resolution, so you can tell when something is just a few meters taller than the rest of the seafloor, and it also tells you if it's harder.

So the multibeam is able to -- Actually, it's the other sonar instrument that can tell how hard the reflection is up off the bottom.

The sound goes into the mud and kind of comes back with less of a firm signal, and in this case, it bounces much harder.

So you can tell kind of the hardness, and you can tell how high up.

And he was able to see little bumps on the seafloor, and that's where we put the dredge in the water.

I mean, we're all hanging over the side, and he's bringing this thing up, and, oh, my gosh.

He brings up this huge collection of very colorful, beautiful animals and dumps it out on the deck and then proceeds to sort through it.

And everybody's just hanging over looking at all of this amazing stuff, and so, we were just really amazed.

This muddy area where the mouth of the Amazon reaches and the fresh water reaches the ocean's salt water -- is that right?

So you get sort of a unique mix and ecosystem?

In most rivers, there's an estuary, right?

So, the river meets the sea, and the tides carry the ocean in and out of this sort of enclosed body.

But the Amazon is so huge.

Even though it's many, many -- 40 miles wide.

I mean, you feel like you're in the middle of the ocean when you're sitting at the mouth of the river, 'cause you can't see either shoreline.

And yet, the water's fresh.

The velocity is so fast -- the discharge is so high that it comes all the way out to the ocean and just hits the ocean like a wall.

And it's only about 30 feet deep right at the mouth.

In fact, it was a little tricky getting the ship in there and not [laughing] grounding the ship.

Oh, okay.

We had to sail really carefully up sort of a channel during the high tide so we could get to the mouth.

It's less dense, so as the seafloor kind of falls away, it lifts up away from the seafloor and forms about a 30-foot-thick layer of fresher water as it mixes.

So it gets salty quickly.

It doesn't stay zero salinity for a long time.

Maybe 3 or 4 miles away, it's now a little bit salty.

But it's very muddy.

But it's lifted up above the seafloor, so these reefs are actually underneath that layer.

They're not living in the muddy outflow from the river.

They're living 50 meters, or 150 feet, below the surface.

But the trick is that the plume is over the top of it, blocking all the light.

And when you think about reefs, you think about needing light, and this plume is clearly blocking the light.

So, does that mean that you found different types of plant and animal life because of this different environment?

This is the coast of Brazil.

And here's the Amazon River mouth.

And the plume is heading offshore.

It's quite large.

And so you can see in the south, the species are different from the species in the north.

And we found true corals -- reef-building corals -- and other kinds of corals -- the non-reef-building corals -- in the south.

'Cause they need the light.

But they're able to survive some of the year in the dark.

That's what's kind of interesting, is that they're able to tolerate the low-light conditions.

As you go further north, there were no more reef-building corals.

There were lots of reef animals, like brittle stars and sponges.

There was a lot of just beautiful, beautiful, colorful sponges.

They don't need the photosynthesis from the sunlight.

They're just able to feed on -- My hypothesis is that they're feeding on all the food that's coming from the plume.

From here, what are some of the questions that you and other researchers are trying to use this discovery to answer?

Because at this time, we're also seeing other reefs around the world being threatened by warming waters and changes that's making on their ecosystem.

These reefs may serve to tell us something about how marginal reefs are doing on the planet.

Marginal reefs?

Marginal reefs in the sense of that they're not in optimal conditions.

They're living in sub-optimal conditions, so they may be a little bit more resilient, maybe, to some of the conditions.

Because they're so deep, the tendency is to think that they're kind of immune from human impacts, but in fact, they're not.

They're sitting in the same warming water.

I mean, they're in the surface layer, so they're sitting in the same warming water and the hot acidity water that the other reefs around the world are experiencing, so they're not immune from that human impact.

And they're also being fished pretty heavily, it turns out.

There's a large artisanal fishery on the Brazil coast.

They're also still really important for the larger fish.

So lots of reef serve as nursery grounds for fisheries -- large fish.

So they were finding little baby fishes that were juveniles of big open water, blue water fish that, you know, they spend their time growing up in this sort of safe place.

So they're still really important for that.

Well, we can't wait to see what else comes from this accidental discovery.

Patricia Yager, thanks for joining us.

My pleasure.

Forest Service scientists in Asheville, North Carolina, are intentionally setting fires.

By comparing growth in the burn zones to the health of untouched areas, they hope to learn more about the declining giant oak population.

Here's the story.

All right, we got our quercus coccinea under 3 -- under .3 We got a quercus prinus 3 to 6.

We got an acer rubrum under 3.

You've got to know your forest to take an inventory of it.

We got a quercus alba under.

And these U.S. Forest Service technicians know what lives in this oak-dominated hardwood ecosystem.

It's part of the Bent Creek Experimental Forest in Asheville.

Amelanchier arborea under.

We have permanent research plots scattered throughout the burn unit, and so, prior to the burn and then again after the burn, our research technicians come in and do a sample of the overstory, as well as the understory or regeneration layer.

So you're going in and counting what's on the ground in that area?

Yes, within a certain area, we are getting information on the species, as well as how they respond in terms of height growth to the treatment.

We got two more quercus coccinea under.

The U.S. Forest Service is experimenting with the reintroduction of a totally natural technique to help manage the oak forests of the southern Appalachian Mountains.

Mother Nature used it extensively before and during the early European settlement of the area.

It's called fire.

We are looking at how prescribed fire affects the hardwood regeneration layer, as well as the overstory layer in these forests.

Forest Service personnel used a controlled burn to clear this area in 2013 and again in 2014.

Technicians made an inventory of what was growing in controlled survey plots before the fire and then at regular intervals after the burn.

They will continue to inventory what is growing in the same survey plots for the next three years.

We are looking at how the oaks respond to the fire, yes.

Yeah, if you look over here, is this a sign of success?

It looks like there are things growing in the forest.

Well, it's way too early to say if fire has benefited oak right now.

This is a red oak.

This has been top-killed by fire, so trees are susceptible to mortality following fire.

But all the hardwood tree species in this forest ecosystem sprout back.

So this oak, which is a red oak, has been top-killed by fire but has sprouted back.


Now, why don't all of the trees burn, I guess?

Is oak a little more able to withstand fire?

Yeah, so some tree species, such as oak, are able to tolerate fire a lot better than some of the other species, like red maple, with a really thin bark.

You can tell the oaks -- they have a thicker bark and they're able to just tolerate the heat better.

Hike through areas of the Bent Creek Forest, and you'll get a better understanding of the Forest Service study.

The area that was burned is more open.

You can spot the burn marks on the oak tree bark.

But that openness means sunlight can reach the ground, encouraging more trees to grow.

It's also a more open area for wildlife.

The reintroduction of fire into these oak-dominating ecosystems is a goal and objective associated with forest management across the southern Appalachians.

Contrast that with the forest area that's been left to grow untouched.

The understory between the tall trees is filled with smaller trees and bushes.

It's very dense.

And while the forest needs both types of habitat, the Forest Service is focusing on oak because the once-dominant species is in decline.

It's got a DBH of 14.5 centimeters.

Oak trees were overharvested for timber and to clear land for farming.

Fire suppression is one possible reason why the oaks haven't bounced back.

Oak trees need fire to clear out the forest floor.

Other possibilities include pests, climate change, which favors other types of trees, and even the increased consumption of acorns and seedlings by growing mammal populations.

In these oak-dominated systems, we're often managing for the oak component, so we're trying to sustain that oak component across the landscape and over time.

We have a variety of tools to accomplish our management objectives.

We can use prescribed fire.

We can use timber harvesting and herbicide.

So we have a variety of tools that we can use to accomplish those specific management objectives.

And that wraps it up for this time.

For more on science, technology, and innovation, visit our website, check us out on Facebook and Instagram, and join the conversation on Twitter.

You can also subscribe to our YouTube channel.

Until next time, I'm Hari Sreenivasan.

Thanks for watching.

Funding for this program is made possible by... The Corporation for Public Broadcasting.

Sue and Edgar Wachenheim III.

And contributions to this station.