- I'm Dr. Peter Kalmus.
I'm a climate scientist, and today I'll be
answering questions from Twitter about our planet.
This is Earth Support.
[upbeat music]
@_Ruthhyyy
asks, "I'm so over this planet.
Are there any planets out there we can live on yet?
'Cause this some bull."
No, there are no planets out there
that we can live on and that we can currently get to.
And Mars totally sucks.
It's cold, it's a desert.
There's no water.
You're bombarded by radiation that would give you cancer.
It's just basically a cold, awful hellscape of a planet
and I love this place.
I love earth and I'm here for life.
@amandajpanda asks, "Hurricane season starts June 1st.
So do they just wait until that day or how does it work?"
Hurricanes are powered by hot ocean water
and you get hotter water in the summertime and in the fall.
So that's why late summer,
fall is the prime hurricane season.
@AB_LSOC
asks, "How do satellites monitor the weather?"
Excellent question.
So there are two main kinds of weather satellites.
You got polar orbiting satellites,
which stay in the same position relative to the sun
as the earth rotates underneath them.
So they'll sample the planet two times per day,
once in the daytime,
and then once in the nighttime descending.
And then you also have geostationary satellites,
which are looking at the earth
and rotating along with earth.
So they're always seeing the same thing.
Then there are four main kinds
of sensors on these satellites.
You've got optical imagers, which can see clouds,
how high the clouds are.
You have infrared and microwave sounders,
which together can give you information about
how much moisture there is
in the air columns from the surface of the planet
all the way to the top of the atmosphere.
And then finally you have radars, which can seek rain
and snow and other kinds of water that's falling
from the clouds to the earth.
Satellites are indispensable
for studying the weather and the climate.
@Paul_McGuire asks, "Cloud physics?
Um, what?
Me no understand, professor."
Yeah, so is one of the most complicated parts
of the earth system in my opinion.
And I'm saying that as somebody
who used to study cloud physics.
We understand them at multiple levels
using different kinds of models.
If you're looking at them with a radar,
you'll define it in one way.
If you're looking at it with optical imagery,
you might define the edges of clouds another way.
You've got clouds at different layers.
The physics works both on the very smallest scale,
the tiny water vapor particles and aerosols
that can nucleate the clouds,
to the very largest scales of atmospheric circulation
and these, you know, huge weather patterns.
There's a whole universe of science just in clouds.
@ngsscience asks, "How do global winds
and ocean currents work?
How does density play a role?"
So the ultimate driver of both the ocean currents
and the air currents is the sun.
So the sun hits the equator, it's hotter at the equator,
much colder at the poles.
Air goes up from the equator and it heads towards the poles,
and it comes down right around California or Spain.
So you have westerly winds in the subtropics.
and then in the equator you have the trade winds,
which are coming from the east and going to the west.
And the same thing again, remember, is happening
in the Southern Hemisphere in the opposite direction.
The ocean works in a similar way.
In the Atlantic, you have the gulf stream
going up the coast of North America.
It gets colder as it gets closer to the poles.
Colder air is denser.
It gets saltier as some of that water
on the surface freezes.
And that also makes it denser.
And that denser water sinks down
into the depths of the ocean
and then goes along the ocean floor
back towards the equator.
Melting water from the Greenland ice sheet,
by adding fresh water to the ocean water,
the fresh water is less dense so it doesn't wanna sink down.
And that could cause, potentially,
that overturning circulation
to change or maybe even to stop.
@KevinBurke14 asks, "What is polar amplification again?"
So very simply,
when you have ice sheets covering the Arctic Ocean,
they're white, they're very bright.
You look at them from space and they reflect
a lot of sunlight.
When that ice melting goes away,
you're left with dark ocean water,
which absorbs a lot of sunlight,
which makes the planet get even hotter and more ice melt.
@MGRYouth asks, "Why is climate change happening?"
80% of the global heating that we're experiencing
on the planet today comes from burning fossil fuels,
which are buried carbon, coal, oil,
fossil gas that's locked under our ground.
We burn that stuff and each carbon atom
combines with two atoms of oxygen from our atmosphere
to make carbon dioxide, CO2.
The other 20% comes from methane.
And this is another molecule created by animal agriculture.
So cows breaking down grasses in their stomach
and then burping out this methane,
and nitrous oxide which comes from fertilizers.
So this stuff in our air actually acts like a blanket
and means that more energy from the sun is coming in
than is escaping right now from space
and that makes our planet hotter.
@vijaygajera asks, "What is the difference between
global warming and climate change?"
Global warming, I prefer the term global heating.
And that is the whole planet getting hotter every year
on average because of burning fossil fuels.
That planetary heat causes all of this chaotic change,
which we could call climate change.
The things like the fires and the flooding, the heat waves.
And I prefer the term climate breakdown
because that's what it really feels like to me.
It's not just innocuous, innocent change.
It's all kind of heading towards world that's very different
than the world we're used to,
and that our civilization is adapted to.
@coffeejelly44 asks, "Why is the coral reef dying bad?
Maybe earth is on to bigger and better things."
I love coral reefs.
They're these crazy, colorful alien animals
that have solar panels embedded right in their flesh.
And coral reefs are dying around the planet
because of ocean heatwaves.
So just like on land, we're experiencing worse and worse
heat waves as the planet gets hotter.
Ocean animals and plants are also experiencing
worse and worse heat waves as the oceans heat up.
Scientists who study the fossil record have found
that there have been five previous,
what we call mass extinctions,
on planet earth where you just have a huge dip
in biodiversity because so many species died.
One of them was when the dinosaurs died
when a giant asteroid hit the earth.
We're in the sixth mass extinction right now
and a big part of that extinction pressure
is the planet heating up because of burning fossil fuels.
And it's true that after about 10 million years,
the biodiversity will recover from this.
But there's a whole lot of death and suffering
between now and 10 million years from now.
And I firmly believe that we should do everything
we can right now to stop that death and suffering.
@USNA_73 asks, "Carbon cycle?
Explain please."
Carbon.
This black atom with 12 protons and 12 electrons.
The main component of coal and oil and fossil gas.
Our bodies are made out of it.
It's in the atmosphere.
It's in trees.
It's in the food that we eat.
We eat the food, it goes in our body,
our body breaks the food down, turns it into energy.
We breathe it out as carbon dioxide,
which goes into that atmosphere,
goes into trees again, the cycle continues.
There are several reservoirs in the carbon cycle.
You've got land plants, you've got fossil fuels,
you've got the ocean, which dissolves carbon into the water,
and then you've got the atmosphere,
which is like the Grand Central Station
that helps carbon move between these different reservoirs.
All of the transfer of carbon between these reservoirs
was roughly in balance until quite recently
when one species on this planet decided to dredge up
huge amounts of fossil fuels,
so carbon from that fossil fuel reservoir,
burn it and put it into the air reservoir,
which is another way of understanding
why the planet is heating up right now.
@furaidisaw asks, "Just learned that NASA scientists
were arrested for protesting about climate change,
and that climate change is so bad
that we only have three years left to save our planet.
Why am I not seeing this more?"
Well, I know of one NASA climate scientist
who got arrested protesting climate in action
and that's this guy.
A lot more should do it though.
Now, we do not have just three years to save the planet.
How it works is the longer we burn fossil fuels
the worse it will get.
This is a planet-wide emergency,
but so far world leaders aren't acting like it.
The media is not reporting like it.
We have to heat our homes,
we have to get around on the surface of this planet.
But we now have alternatives to do all that
without fossil fuel industry.
What we have to do is sever the influence of that industry
over our politicians and our media
so that we can actually implement these alternatives.
And in my opinion,
that's gonna take a really strong grassroots movement,
which is why I chose to engage
in non-violent civil disobedience.
@ATomalty asks, "When a climate alarmist says that AGW,"
anthropogenic global warming,
"is causing storms to become more violent,
ask them what is the actual cause of this?"
A hotter atmosphere holds more water.
That's basic physics.
Every degrees centigrade that the atmosphere gets hotter,
it's 7% more water, which is actually quite a lot.
And that means stronger rainstorms, more flooding,
more rain.
He goes on, "When they say that CO2 is causing the planet
to heat up, ask them why does the satellite data show
no net warming in 33 years?"
The satellite data, absolutely, and all the other data sets,
by the way, absolutely show that the planet is heating up.
So this shows the global average surface temperature
reconstruction from all the thermometers on the planet
and proxies going back to 1880 to the present day.
And it is a clear trend.
That should be flat.
That should not be going up.
Now if you look at this next plot,
which shows the global ocean heat content
and 93% of the excess energy coming into our earth
is getting absorbed by the ocean.
This is perhaps the fastest global heating the earth
has ever experienced
@PorkFriedSpice asks, "How much longer
until Florida is underwater?
I've heard that very few property insurers
dare to offer services there
because of problematic climate forecasting."
So it depends on what part of Florida you're talking about.
The highest point in Florida is about 350 feet
above sea level.
But there are some parts of Florida,
and some of the most valuable parts like Miami Beach,
that are just a little bit above sea level.
They're already seeing what's called sunny-day flooding,
which is when there's a high tide.
You get water in the streets, water in the buildings.
By 2300, we could expect between maybe 10 feet
and 50 feet of sea level rise depending on how much
of this CO2 we continue to emit.
But there's huge uncertainties in those estimates.
It could be much worse than that.
And it's gonna keep getting worse after 2300.
@40dargus asks, "How can air travel be decarbonized?
Is there an alternative to fossil fuel to fly planes?
Just wondering."
Not at this time.
We can fly planes with batteries,
but they only go a couple hundred miles
because you can't store enough energy in those batteries
to lift it up on planes.
The batteries are just too heavy.
The batteries would have to improve about a factor of 10
in terms of their energy density
in order to be useful for planes crossing oceans.
Another thing you hear about is biofuels,
which is basically running the airplanes on vegetable oil.
And that works, but there's simply not enough of it.
So we can't run commercial aviation at its current scale
without fossil fuels.
@pphnarg asks, "I'm genuinely wondering what can I do
to reduce climate change?
Toodles."
This is a great question,
and I think of it in two categories.
So first is direct action and second is,
what we call, individual action.
Direct action is more important.
And by this I mean get really noisy
about how much you want world leaders
to act on climate change.
And when I say, "Really noisy,"
I am also talking about nonviolent civil disobedience.
The second category is using less fossil fuels yourself.
The main thing I did was to end flying.
So I haven't flown on a plane since 2012.
I don't wanna get on a plane because it feels
really gross to me knowing how much emissions
that plane causes.
@logging_on_web asks, "Realistically, is there any way
we are going to reverse climate change?
Like, are there any inventions or solutions in the works
to do this?
Trying to find something positive
in regards to the future of the planet?"
Unfortunately, no, there is no way
to reverse global heating.
Now, there is one technology,
which I think has gotten over-hyped called carbon capture.
Last year the world's biggest carbon capture plant,
ClimateWorks, went online in Iceland.
With much fanfare, they announced that they could take
4,000 tons of CO2 out of the atmosphere every year.
If you do the math, that's just three seconds worth
of humanities' emissions in one year from one plant.
You would need 10 million such plants
at huge expense to actually deal with
all of humanities' emissions.
To me, it's not realistic at all
to think that we're going to reverse this.
We need to stop it.
One of the big takeaways here
is that when we stop burning fossil fuels,
the damage will stop.
@ElevenOneThree asks, "When will climate change stop?!"
Question mark, exclamation mark.
Great question and it has a very easy answer.
When we end the fossil fuel industry
and the animal agriculture industries.
@KristinSmistin asks, "Whoa.
Chemically, how does methane react in our atmosphere
and how does it affect our climate?"
That's a great question.
So methane is the second biggest cause
of global heating in terms of the different molecules
in our atmosphere after CO2.
It's an interesting molecule.
One carbon with four hydrogens.
Once this goes into the atmosphere
it's an extremely powerful greenhouse gas,
around 50 times more powerful than CO2,
but it only lasts roughly 10 years.
Whereas CO2 stays in the atmosphere
for hundreds or thousands of years.
Two main ways excess methane is getting into our atmosphere.
Number one from drilling and mining of fossil fuels.
So when you're getting this stuff out of the ground,
you get some of this stuff escaping
and leaking into the atmosphere as well.
And second, from various forms of agriculture
and food waste decomposition.
@jazzyjazzhill asks, "Why can't Cali be normal for a moment?
What's up with this heat?"
Upside down smiley face.
We have not reached a new normal.
We are on an escalator towards hotter
and hotter temperatures, worse and worse heat waves.
But then you have this extreme drought
which is at least partially caused by climate change
and that's causing, you know, water shortages,
massive wildfires,
so the trees don't have enough water to drink
and so they die, and then forest burn very easily.
So when you have multiple impacts in one place
it just feels, it can feel like Armageddon.
And that's exactly what we're seeing in California
and frankly all over the entire planet.
On average, this is the hottest summer
you've ever experienced.
It's also the coolest summer for the rest of your life.
So those are all the questions for today.
Great questions.
Thanks for your interest in our planet.
It's the only one we got
and I think it's pretty important to save it.
This is a climate emergency and this was Earth Support.