There’s a lot of conflict about climate
change.
Does eating beef hurt the environment?
How can global warming be real if we have
thicc ice and snowstorms?
If that sounds wild to you, that’s ok.
Those are just parts of the full, epic drama
that is climate change.
It sounds crazy until you get the full picture,
so let’s get started!
Our climate always changes.
Earth is here, the Sun is
here, when we move closer to the sun, we get hotter
But Earth is getting much hotter, so
Whose fault is that?
What?!
Yeah we are the biggest cause of global warming.
Don’t tell me it’s because you’re hot.
Benedict Cumberbatch is the only person who's allowed to say that.
Enter act 1 of this story!
The Sun keeps us warm by beaming short-wave
ultraviolet rays to Earth.
The Earth radiates it back out as heat, or, scientifically
speaking, long-wave infrared rays.
Some of it goes to space, and the rest are
trapped around our earth thanks to greenhouse gases.
Greenhouse gases are like a blanket around the earth.
The more greenhouse gases in the atmosphere,
the thicker this blanket, and the more heat
is trapped on Earth.
It's like how heat can't escape through the glass in a greenhouse... That’s the greenhouse effect.
So what are greenhouse gases?
Some common ones are carbon dioxide, methane,
water vapour, nitrous oxide, and chlorofluorocarbons
We emit a lot of GHGs, especially CO2.
What comes to mind when I say greenhouse?
Right, trees!
Trees do something really special called photosynthesis
where they take CO2 from the atmosphere and
convert it into chemical energy for themselves,
and release oxygen back into the atmosphere!
What do we do with this biological marvel?
We burn them.
You see, we need a lot of space to grow crops
and raise livestock.
According to the World Wildlife Fund, agriculture
is the largest single cause of deforestation.
As a result, we have much fewer trees to remove
carbon dioxide in the air.
At the same time, cows emit a huge amount
of greenhouse gases a year.
Obviously there's methane in farts, while the bacteria that feed on poop release carbon dioxide.
It's a simplified description -
Essentially, a lot of greenhouse gases are emitted by cows because they fart and poop a lot.
You can change that by eating less beef, or
none at all.
We also use a type of land called peatlands
for agriculture.
Peatlands are waterlogged and made up of decayed
organic matter, so they contain a lot of carbon.
When we drain peatlands to grow crops, the
organic matter is exposed to oxygen.
This speeds up decomposition, which we now
know releases CO2.
Worse still, when the peatlands dry up, there’s
a greater risk of peatland fire which releases
CO2 and N2O.
Now that we know how hot it’s getting, what
are the consequences?
TL;DR, here is a list.
Number one: polar ice caps melt.
It’s important to know the difference between
sea ice and land ice.
Sea ice is frozen sea water, so imagine freezing
a cup of water, then letting it melt.
The water level remains the same.
Now land ice is ice that comes from land,
like glaciers and ice sheets.
Sometimes the ice flows down, forming an ice
shelf that’s still connected to land.
Sometimes parts of the ice shelf break, forming
ice bergs.
Let's go back to our cup of water.
Land ice in the sea is like adding ice cubes
to water.
When land ice melts, the water level in the
cup rises.
Now more on the melting process: there’s
something called ice albedo feedback, which
is not the ice judging you for bad environmental
decisions, even though it should.
Ice albedo is the proportion of radiation
that’s reflected off the ice surface.
That sounds like jargon so here’s a simple
example:
Another name we give light that beams down from the Sun is radiation.
In the case of thick ice, the white surface
reflects 90% of radiation and absorbs 10%.
So the albedo is 0.9.
Let’s say the ice melts completely.
Now the dark ocean water absorbs 90% of light
and reflects 10%.
The albedo is 0.1.
This is a positive feedback mechanism, because
when more ice melts, more of the dark ocean
water is exposed.
That means more heat will be absorbed, warming
the ocean and causing even more melting.
So it’s a cycle that gets more and more
severe.
The opposite of this is cloud feedback, which
is a negative feedback mechanism.
When the ocean gets warmer, there’s more
evaporation, which forms more clouds which
prevent radiation from passing through to
Earth, which makes the ocean cooler.
As in, less warm.
So negative feedback is a cycle that leads
to an opposite effect.
Great! Or should I say... nICE =)
Now back to the ice.
We know that land ice melting causes sea levels
to rise.
What’s more, when the ocean gets warmer,
it expands.
So the sea level rises some more.
What happens is, shorelines get eroded because
the waves crash even further in.
For people who live along the coast, that
means more destruction and even displacement
caused by flooding.
Coastal ecosystems like mangrove forests are
also destroyed when the mangroves get uprooted
by waves.
Next, when temperatures rise, permafrost starts
to thaw.
As the name suggests, permafrost is a permanently
frozen layer of soil
It lies underneath the active layer, which is the layer that melts in summer.
The bad news is, when the permafrost thaws, organic matter start to decompose, releasing
CO2 and methane.
Here are two more interesting facts about permafrost.
You might have also heard of so-called zombie
pathogens.
In 2016, a heat wave thawed the permafrost
in the Arctic, revealing reindeer carcasses
that had died from anthrax bacteria.
The bacteria also thawed, spread across the arctic,
and infected dozens of people.
You can probably consider it a consolation that anthrax is basically known
for hibernating in soil and then springing back up.
Other viruses found in permafrost like smallpox
and pneumonia haven’t been able to survive,
mainly because they’re used to occupying
warm, cozy bodies and not freezing temperatures.
Another effect of melting permafrost that
made the news is the flooding of the Global
Seed Vault, also in 2016.
This vault is buried in a mountain deep within
the Arctic circle, and contains nearly a million
packets of seeds.
It’s meant to provide a failsafe protection
against disasters that could wipe out our
food sources.
Because of the heatwave, water flooded the
tunnel and nearly reached the vault, almost
Think about it: the global seed vault is supposed to last us for generations.
That's some food for thought.
Next we have extreme weather.
Not just heat waves, but also storms and hurricanes.
You know the drill.
Higher temperatures mean more evaporation,
which means more water vapour in the air,
which leads to more rain.
Theoretically, as a cycle, this is perfectly
balanced.
But nature is not Thanos.
What happens is rain clouds get blown to other parts of the world -
- so while water is evaporating from one place, another place keeps raining.
This leads to 2 extremes: drought and heavy
storms.
The same thing applies to heavy snow.
If the ocean gets warmer, that means more
evaporation, and when all this water vapour
meets cold air, you get more snow.
When you have heavy rainfall, there’s a
higher risk of flooding, especially in urban
areas because it’s harder for the water
to drain.
That could lead to pollution and waterborne diseases.
Global warming also stresses our freshwater
supplies.
Glaciers are our natural reservoirs, storing
water as ice in winter and melting in summer.
With global warming, the ice melts earlier,
so less water is left when summer actually
arrives, ie when we need it most.
Going back to flooding: the dirty water might
get flushed into our own reservoirs
contaminating our waters, again...
And with rising temperatures, bacteria can multiply in our reservoirs much more easily.
That's kinda gross.
Here's something a bit more colourful - corals!
First of all, corals are animals.
They have a hard protective limestone skeleton
called a calicle, and inside is their soft
squishy polyp.
Firstly, a polyp attaches to a rock on the
seafloor and buds into thousands of clones
connected by their calicles, forming a colony.
A reef is formed when colonies join to other
colonies.
Corals are colourful thanks to a micro algae
called zooxanthellae that lives in them.
Zooxanthellae undergo photosynthesis and provide
organic carbon for corals.
In return, corals provide zooxanthellae with
carbon dioxide and UV protection.
Warmer water causes zooxanthellae to leave
the coral, resulting in coral bleaching.
The corals then starve and become more vulnerable
to disease.
When you think about how much more carbon
dioxide there is in the air, naturally there’s
more that will dissolve in the ocean.
Carbon dioxide being an acidic gas leads to
the acidification of seawater, which prevents
corals from absorbing calcium carbonate to
maintain or grow their skeleton.
That’s bad news for sea animals that depend
on corals for survival, whether as a habitat
or part of the food web.
As for poikilotherms like fish and insects,
Warmer temperatures would trigger tropical
fishes for example to swim towards the earth’s
poles where the water is colder, and therefore
contains more oxygen.
For similar reasons, insects migrate to new
habitats
like the green stink bug which destroys crops for
a living.
It’s hard to blame them, because insects
have a narrow thermal safety margin, meaning
that anything too hot or too cold for them
will kill them.
Kinda like a grotesque Goldilocks.
That kind of applies to us too.
Heatwaves cause a lot of heat-related death
because we can’t survive beyond a narrow
range of temperatures.
Congratulations for making it this far, because now we're going on a trip - also known as a GUILT TRIP! ^_^
Allow me to bring your attention to this adorable
critter called the American Pika.
Global warming has forced it to higher and
higher altitudes, and it may soon run out
of places to go.
Migration is serious because it forces animals
to move to new habitats where they may face
native predators or competition they aren’t
adapted to face.
Even the timing of migration could matter.
Take for instance at the great tit. Don't laugh.
Because of global warming, they've kind of been knocked out of sync.
The mom migrates to
her nesting ground too early, so her chicks hatch
way before there are enough insects for them
to feed on.
It’s not a climate change video if we don’t
talk about polar bears.
In the Arctic, melting sea ice means less
ice algae for zooplankton to eat.
That leads to less zooplankton for Arctic
cod, and less cod for seals.
What eats seals?
Polar bears.
As you know, polar bears are BEARing the brunt
of our actions.
Melting sea ice means fewer and smaller platforms
for polar bears to rest or travel on.
They would also have to crowd together in
the same place, which makes disease spread
more easily.
Young polar bears might also get trampled
in such a small space.
It’s affecting their population as well.
Polar bears are spending more time on land
and hybridizing with grizzly bears, so there’s
a chance Grizzly and Ice Bear are actual brothers.
BUT to be scientifically accurate,
when grizzly bears mate with polar bears, their kids are actually hybrids called grolar bears.
Panda is still definitely adopted though.
In other Arctic news, the Arctic hare can
change its coat colours depending on the season.
Its white in winter and brown in summer.
When the snow thaws earlier due to higher
temperatures, the hare will still be white
when everything around it is brown.
If a wolf sees this, the hare doesn’t stand
a chance.
All that said and done,
let’s move to something a little bit more...
vegetative.
Plants.
They are pretty shady because there’s so
much going on with them, but we can't see it.
For example, they deal with climate change
by
1: closing the stomata to reduce water loss
during transpiration
2: Increasing their root to shoot ratio to
absorb more water
And 3: Reducing the number and size of leaves
Unfortunately, points 1 and 3 also affect
the plants’ ability to photosynthesize,
which hinders their growth.
Another side effect of climate change on plants
is that their reproduction is disrupted because
of synchronization issues.
Yes, just like Apple.
WRONG SPECIES I meant the early spider
orchid.
This orchid looks like a female miner bee
and even releases the same pheromones to seduce
male bees, into something called “pseudocopulation”
which pollinates the orchids.
Normally, female miner bees emerge later than
males.
But warmer temperatures are making female
bees emerge 15 days early, meaning that males
are less likely to visit the orchids.
Which is really sad for the orchids because
FIRST of all they deserve fun time too, and
SECOND of all they need to survive.
As populations, plants are also starting to
shift to cooler regions, albeit more slowly.
Plants, like most living organisms have an
ideal range of environmental conditions, so
when temperatures rise, the population shifts to higher altitudes, or higher latitudes towards the poles
Tropical forests however
may not do so well because climate change
is happening so fast, many species might not
be able to migrate in time.
That could lead to... *drumroll*...
extinction.
At this point there’s a slight possibility
that plants and polar bears aren’t really
your thing, in which case you’ve come to
the right section!
How does climate change affect us specifically?
Earlier we’ve talked about deforestation
and plants possibly going extinct.
Now tropical rainforests like the Amazon are
huge resources for pharmaceutical products,
and by driving them extinct we lose important
health discoveries.
For example, we take curare from the curare lianas..
We need curare from the curare lianas  plant in the Amazon to make muscle relaxants
for treating Parkinson’s
Disease and multiple sclerosis.
Similarly, coral reefs are known as the medicine
cabinets of the 21st century.
Being stationary, they have evolved chemical
defences to protect themselves from predators.
Even if you have no feelings for coral, you
can’t deny their incredible potential that
we are missing out on if we just let them bleach
and die for nothing.
Now, food!
We return to the rainforest, because surprise
surprise, that is where 80% of our food comes
from.
There is way more genetic variability in forest
plants compared to the crops we grow, which
all come from the same strain.
In the event that our crop strain gets wiped
out, we need the different genetic traits
from forest species to produce more resilient
crops.
On that note, climate change is a serious threat
to our food.
Higher temperatures allow pests and weeds
to thrive and kill our crops.
More rainfall could lead to flooding and kill
our crops.
When sea levels rise, salt water could intrude into groundwater,
and guess what?
Kill our crops.
When it comes to animals, our livestock are
more likely to experience heat stress
thanks to global warming.
And salmon!
When there’s less and less ice there's also less and less water, which means the
streams that salmon swim in will be more shallow,
which makes it easier for bears to eat them.
Less for you if you love salmon!
Warmer stream temperatures also make it easier
for them to fall sick.
Less salmon for you!
You know what, I’m just going to put a picture
here.
If you think you have it rough, the fish have
it rougher.
TL;DR.
Global warming is the enemy of anyone who
even vaguely likes food.
Now there’s a whole other section on climate
change causing diseases
but it also has stuff about viruses and the immune
system which are really full-fledged stories
on their own
and this video has gone on for long enough!
I promise the next
video will be a lot easier to handle - there
will be a giveaway!
Naturally, the video is going to be about
environmental friendliness, which I’ve been
paying more attention to recently since it’s
Plastic Free July and all.
So stay tuned for that, by subscribing, wink
wink, and leave a comment if there’s anything
you’d like to see next.
Thanks!
