Hey, I'm
Kal Penn, and this is Getting Warmer.
Look, I'm a natural optimist, okay?
Like, I've never bought an extended warranty in my life,
and I genuinely think it's possible for humanity to pull together
and avoid the worst impacts of climate change.
But even if every country reached the net zero targets committed to in the Paris
Agreement, we're still on track for several decades of warming.
And that's got a lot of people who are less optimistic than me,
considering some very extreme plan B's.
Could blocking out the sun actually help reduce the temperature?
China says it will try
to protect its grain harvest from intense drought by using chemicals
to generate rain.
Creating a massive chemical cloud that could cool the earth.
Reflecting sunlight to cool the planet, such as with space based mirrors.
Now, maybe you find it easier to imagine quitting fossil fuels
than to imagine surrounding the earth with giant space mirrors.
But it's worth getting familiar with some of these last resorts
so that you can decide for yourself whether they belong in the world
of science fiction or science nonfiction.
So let's start with one of the biggest ideas.
It's called stratospheric aerosol injection.
This is where we replicate volcanic eruptions by shooting sulfur dioxide
into the stratosphere to reflect sunlight, cooling the planet.
So basically, we would counteract the pollution in our lower atmosphere
by injecting a different kind of pollution into the upper atmosphere.
As you probably guessed, because you're not an idiot, there is a downside.
First, you'd need to keep this up indefinitely.
And second, studies show that it could cause severe droughts in the Global South,
which has some pretty serious humanitarian ramifications.
And political ones.
Because if one country shoots chemicals into the sky
and it ends up killing a bunch of people in another country,
that might technically make it a bioweapon?
Feels problematic. Moving on.
A more grounded backup plan is to recover the fossil fuels
that we burn and literally bury them underground.
This is called carbon removal.
We're already doing this actually on a small scale.
And there are two kinds.
One is carbon capture and storage.
Think of this as like a giant Roomba duct taped to the top of a smokestack.
It collects CO2 as it's emitted and then it sends it for further processing
or it stores it underground.
Currently, only about 0.1% of global emissions are captured with this method.
But America's landmark climate law, which zero Republican senators voted for,
has provisions to increase its use 13 fold by 2030.
The other carbon removal
method, slightly more science fictiony, is called direct air capture.
If carbon capture and storage is like a Roomba duct taped to a smokestack,
then direct air capture is like a Roomba for the whole sky.
A sky-ba? This is the world's largest
direct air capture plant in Iceland.
It takes 4000 tons of CO2 from the air each year.
Unfortunately, that only covers the emissions of about 250 Americans.
Ramping up carbon capture and storage to a meaningful scale
would require tens of thousands of these things running for decades,
using a massive amount of energy and storing all that
captured carbon underground forever.
But in spite of those challenges, investment is ramping up from private
companies and the American government, which is spending three
and a half billion dollars to develop four direct air capture hubs.
But if these giant life support machines for the Earth are a little too desert
planet of Arrakis for your taste, there are more natural options.
The world's oceans are natural carbon sinks, and some scientists
have experimented with ways to get the oceans to absorb
more CO2 - like ocean fertilization.
The idea here is to stimulate the growth of plankton which soaks up carbon.
And you do that by dumping huge amounts of iron into the ocean.
Look, I said it was an idea.
I didn't say it was a good idea.
Another ocean experiment under investigation is deacidification,
where we make the ocean less acidic by, again, dumping stuff into it.
In this case, rocks.
Scientists in Norway are currently researching what impact
changing water levels would have on oceans ecosystems.
So we traveled there to get a closer look at their operation.
We also checked in on a company growing carbon-sucking algae in Morocco.
Are these viable ideas to combat climate change or will messing
with the oceans get us all into hot water? Hot, salty water?
Let's take a look.