How Will Climate Change Continue to Affect Us? (13:08)
Think about the following questions as you watch the video
- Why are small amounts of warming significant when it comes to climate?
- How are extreme weather events like heatwaves and wildfires connected to climate change?
- How do climate models contribute to our understanding of climate impacts?
- According to this video, what are the “ripple effects” of climate change? What’s one example of a ripple effect?
- What’s a feedback loop and how do they contribute to the impacts of climate change?
: Many of us have grown up with the knowledge that the threat of climate change is looming.
: But it’s not some far-off danger anymore. Climate change has already shown up at our doors,
: busted into our living rooms, and is now on our couch eating our mac ‘n’ cheese.
: It’s happening; it’s been happening; it will keep happening.
: No matter how many polite hints we drop — and even if we throw everything we’ve got at decarbonizing our lifestyles —
: this unwanted guest isn’t going to see itself out right away.
: It takes time for our changes to kick in, and, real talk: we can’t fully undo the damage that has already been done.
: But. It's not time to hand over the keys and surrender.
: There are ways to slow and solve this before it reaches a number of worst-case scenarios.
: But we will have to deal with the current effects of climate change along the way.
: Hi hi! I’m M Jackson, and this is Crash Course Climate and Energy.
: [INTRO]
: So far, average global temperatures have already risen a full degree Celsius since before the Industrial Revolution,
: about 260 years ago.
: One degree. Dramatic pause.
: Alright, I get it: that might sound a bit melodramatic. All that leadup for just one degree?
: Sure, one degree outside doesn’t change whether you’re wearing sweatpants or shorts to go jogging.
: But when the entire planet warms by one degree on average,
: that’s a lot of energy added to the system. A lot of change.
: Also, this is an average global temperature, which means some places have warmed less than one degree,
: while others have warmed more.
: For example, the average temperature in the Pacific Northwest of the United States has risen about 0.7 degrees Celsius.
: Meanwhile, in the Arctic, the average temperature has gone up by about three degrees.
: Depending on where you live, you might have already noticed some changes.
: The weird, warm days in winter, or the heat waves that won’t quit in the summer.
: But local warming can have effects way beyond you wearing shorts on your ski trip to Alberta.
: For example, in Spring 2022, India and Pakistan experienced a record-breaking heatwave,
: with temperatures in India consistently three to eight degrees Celsius above average.
: Add in a lack of rainfall, and this led to failed crops and at least 90 fatalities.
: And scientists believe an event like this was 30 times more likely as a result of climate change.
: Similarly, the 2021 Dixie Fire in California was among the largest and most destructive in the state’s history.
: It swept through more than 3,800 square kilometers of land and damaged or destroyed more than 1,400 buildings.
: The fire itself was started by a power line, which isn’t climate change’s fault.
: But before that came two years of below-average rainfall and drought, which were exacerbated by climate change.
: Meanwhile, places that aren’t being baked, are being flooded.
: As glaciers and ice sheets melt, the average global sea level has already risen by around 20 centimeters in the last 150 years.
: 20 centimeters doesn’t sound super dangerous on its own — kiddie pools are deeper than that.
: But this has already been enough to drown a number of low-lying Solomon Islands in the South Pacific.
: And in the U.S., high-tide flooding is happening up to eleven times more often around the Gulf Coast than it was in 2000.
: The United Nations Refugee Agency estimates that on average,
: more than 20 million people are displaced every year by sudden, extreme weather events like flooding, fire, and storms.
: Now, when extreme storms happen, it’s hard to point a finger and say,
: "That single weather event was for sure caused by climate change."
: Instead, what we can say is, "Hey, that storm — the one we all just hid under our desks from —
: that storm was accelerated, made worse, by climate change."
: What’s happening is this: all that extra heat that’s become trapped in the atmosphere
: has increased the frequency and intensity of extreme weather events.
: Basically, climate change has taken your local weather and fueled it up,
: making whatever weather you’re experiencing, bigger:
: bigger droughts, bigger rain events, bigger cold snaps, bigger everything.
: All this is from the average global temperature going up just one degree Celsius.
: Unfortunately, climate and weather scientists have been predicting how conditions are going to
: keep changing in the coming years and decades, and they’ve found that one extra degree
: probably won’t be our stopping point.
: One of the most powerful tools scientists have for making predictions like this are climate models.
: Basically, they take an area of interest — like, a country, or the entire globe —
: and split it into thousands of three-dimensional grid cells that represent the land, ocean, and atmosphere.
: Then, they apply equations based on the laws of physics to those cells to represent how energy and matter
: — like heat and water — transfer between them. So, if you have an extra hot cell near the equator,
: the math will describe how that heat will dissipate into the surrounding cells up into the higher latitudes.
: Then, researchers run millions of calculations, and in the end, the models show how these cells
: — or different regions — will change and interact over time.
: To check how accurate these models are, scientists do something known as hind-casting, where they run
: simulations into the past, and compare the results against historical measurements.
: If predictions for the past are found accurate, it’s likely future predictions will be, too.
: After being tested and refined over and over again, these climate models don’t have the most cheerful news for us.
: Various models forecast that if we keep emitting greenhouse gases at the rate we’ve been going,
: the average global temperature will increase by two degrees Celsius over pre-industrial levels by 2100.
: And because of the way heat is moved around by wind and waves, some places will end up even hotter.
: In the Persian Gulf, where it can already reach 40 degrees Celsius in the summer,
: scientists predict that temperatures will get even higher,
: becoming flat-out intolerable to the tens of millions of people who live there.
: People literally wouldn’t survive outside in the heat.
: The models also forecast melting tundra ecosystems, sea level rise, disrupted ocean and atmospheric circulation,
: and more frequent and intense weather disasters.
: And because of the tricky interconnection of weather across the globe,
: we can also expect extreme cold weather events to become more common —
: more blizzards, more cold snaps, more ice storms.
: And as time goes on, each of these changes will have ripple effects.
: If the planet warms by two degrees Celsius by 2100, average sea surface temperatures
: are expected to rise by a similar amount.
: For as nice as warm water feels when you’re swimming at the beach,
: warmer oceans make it tough for some organisms to survive.
: And while some animals can just try to swim somewhere else, tropical coral reefs can’t move to escape the heat.
: So, they’re predicted to die in huge numbers.
: Scientists think that more than 99% of them could be gone by the end of the century.
: This also means the fish and other animals that call reefs home will die,
: and we would have massive –but preventable– loss in biodiversity on our hands.
: Which isn’t trouble just for the oceans.
: It’s also trouble for the many low-income, coastal communities in places like Kenya and the Seychelles
: that rely on coral habitats for food and income.
: So, if they disappear, these communities will be at risk of becoming more impoverished.
: Where will they get their food?
: And this is just one example of the ripple effects caused by a warming climate.
: You push over one domino, and the impacts are felt way down the line.
: Unfortunately, it doesn’t take a big leap of imagination to see how economic and humanitarian impacts can add up,
: and how they’ll change millions of lives around the world.
: Experts estimate that the global GDP — that’s the total value of the goods and services made by everyone on Earth
: — will actually be lower in 2050 than it is today, even though the population is growing and becoming more developed.
: It’s thought that global productivity will drop by more than 10%, thanks to everything from lower crop yields
: to the loss of infrastructure due to rising sea levels.
: And once that domino falls, so do the standards of living for many people, often worsening pre-existing inequities.
: It’s expected that in South Asia alone — which is an area particularly vulnerable to climate change
: — up to 800 million people will experience a significant drop in their standard of living,
: as higher temperatures affect everything from agriculture to how diseases spread.
: These effects could leave some people unable to afford nutritious food,
: and others with serious illnesses like malaria, in areas that didn’t used to be susceptible to such diseases.
: Similarly, if we keep heading toward a two-degree-warmer world,
: by 2100, sea levels are expected to rise by as much as one meter.
: And because of this, it’s expected that around 630 million people worldwide
: will have to decide whether or not to leave their house, community, state, or even country
: as their homes are drowned or otherwise affected by high tide flooding.
: This will be a decision that people will have to make on an individual, and family, basis —
: a choice between fleeing toward an uncertain future elsewhere… or trying to stay and weather the storm.
: Like we’ve mentioned before, these effects won’t be felt equally everywhere, either:
: Lower-income communities and parts of the world are expected to be the most affected by a warming planet.
: Underscoring the inequity, these areas are often the least responsible for carbon emissions.
: And their systems are the least equipped to deal with the heat, sea level rise, or extreme weather events —
: a.k.a. everything those emissions bring with them. And it gets messier still.
: You see, the Earth and individual climate systems are connected,
: so changes to one affect and exacerbate the other, and vice versa.
: This causes what’s known as a feedback loop.
: For example, as global temperatures increase, they’re melting ice and permafrost in the Arctic.
: And as the ice disappears, it’s releasing huge amounts of the greenhouse gas methane that’s been underground for millennia.
: If all that methane gets out, it’ll mean even faster warming, catastrophic ice melt, and even more methane escaping.
: Basically, if the methane gets out, more methane gets out. A feedback loop.
: Scientists estimate there’s twice as much carbon currently locked away in permafrost
: as there already is in the atmosphere.
: So, the more we release, the faster we zoom toward two degrees and beyond.
: Now, all of this is… well, it’s a tough pill to swallow.
: But it’s not too late to put some brakes on this climate train.
: Some of these effects will be unavoidable, but it doesn’t have to be full-steam ahead to that two-degree-warmer world.
: Climate scientists have evidence that if we pull the emergency brake
: and take major steps to reduce emissions, we could limit warming to just 1.5 degrees Celsius.
: And that half a degree matters a lot. It could help us avoid many of the worst effects of climate change.
: Seas wouldn’t warm as much, saving some coral reefs and the communities that rely on them.
: Dry areas would have fewer issues with water scarcity, and heat waves would be shorter and less deadly.
: And the push for carbon-neutral solutions will help in many other ways.
: Like with climate change itself, cleaning up our act also has ripple effects.
: In countries without reliable access to electricity, the introduction of equitable, renewable energy
: like solar and wind power would help improve healthcare, education, and job opportunities.
: And low-carbon sources of electricity for power and transport also tend to emit fewer pollutants,
: so would help improve air quality in growing urban areas, too.
: It’s the most beautiful, satisfying chain of falling dominos ever.
: And who knows what solutions future generations will bring?
: So, there’s strong evidence that the planet will continue to warm.
: But if you shake your Magic 8 ball and ask it exactly what the future holds,
: it’s probably gonna say something like,
: “It’s up to us.” And we all have a role to play.
: That’s pretty wise stuff from a Magic 8 ball.
: Reducing greenhouse gas emissions now will help reduce some of the worst impacts in the future —
: which is literally life-saving work, for you, for me, for future us.
: And climate action isn’t all or nothing, either. It’s going to be a big task to reach carbon-neutrality by 2050.
: But even if we don’t make it all the way, we can still keep working to limit how much the temperature rises.
: Every half a degree matters and every little bit we can do will improve things for future generations —
: But it’s not some far-off danger anymore. Climate change has already shown up at our doors,
: busted into our living rooms, and is now on our couch eating our mac ‘n’ cheese.
: It’s happening; it’s been happening; it will keep happening.
: No matter how many polite hints we drop — and even if we throw everything we’ve got at decarbonizing our lifestyles —
: this unwanted guest isn’t going to see itself out right away.
: It takes time for our changes to kick in, and, real talk: we can’t fully undo the damage that has already been done.
: But. It's not time to hand over the keys and surrender.
: There are ways to slow and solve this before it reaches a number of worst-case scenarios.
: But we will have to deal with the current effects of climate change along the way.
: Hi hi! I’m M Jackson, and this is Crash Course Climate and Energy.
: [INTRO]
: So far, average global temperatures have already risen a full degree Celsius since before the Industrial Revolution,
: about 260 years ago.
: One degree. Dramatic pause.
: Alright, I get it: that might sound a bit melodramatic. All that leadup for just one degree?
: Sure, one degree outside doesn’t change whether you’re wearing sweatpants or shorts to go jogging.
: But when the entire planet warms by one degree on average,
: that’s a lot of energy added to the system. A lot of change.
: Also, this is an average global temperature, which means some places have warmed less than one degree,
: while others have warmed more.
: For example, the average temperature in the Pacific Northwest of the United States has risen about 0.7 degrees Celsius.
: Meanwhile, in the Arctic, the average temperature has gone up by about three degrees.
: Depending on where you live, you might have already noticed some changes.
: The weird, warm days in winter, or the heat waves that won’t quit in the summer.
: But local warming can have effects way beyond you wearing shorts on your ski trip to Alberta.
: For example, in Spring 2022, India and Pakistan experienced a record-breaking heatwave,
: with temperatures in India consistently three to eight degrees Celsius above average.
: Add in a lack of rainfall, and this led to failed crops and at least 90 fatalities.
: And scientists believe an event like this was 30 times more likely as a result of climate change.
: Similarly, the 2021 Dixie Fire in California was among the largest and most destructive in the state’s history.
: It swept through more than 3,800 square kilometers of land and damaged or destroyed more than 1,400 buildings.
: The fire itself was started by a power line, which isn’t climate change’s fault.
: But before that came two years of below-average rainfall and drought, which were exacerbated by climate change.
: Meanwhile, places that aren’t being baked, are being flooded.
: As glaciers and ice sheets melt, the average global sea level has already risen by around 20 centimeters in the last 150 years.
: 20 centimeters doesn’t sound super dangerous on its own — kiddie pools are deeper than that.
: But this has already been enough to drown a number of low-lying Solomon Islands in the South Pacific.
: And in the U.S., high-tide flooding is happening up to eleven times more often around the Gulf Coast than it was in 2000.
: The United Nations Refugee Agency estimates that on average,
: more than 20 million people are displaced every year by sudden, extreme weather events like flooding, fire, and storms.
: Now, when extreme storms happen, it’s hard to point a finger and say,
: "That single weather event was for sure caused by climate change."
: Instead, what we can say is, "Hey, that storm — the one we all just hid under our desks from —
: that storm was accelerated, made worse, by climate change."
: What’s happening is this: all that extra heat that’s become trapped in the atmosphere
: has increased the frequency and intensity of extreme weather events.
: Basically, climate change has taken your local weather and fueled it up,
: making whatever weather you’re experiencing, bigger:
: bigger droughts, bigger rain events, bigger cold snaps, bigger everything.
: All this is from the average global temperature going up just one degree Celsius.
: Unfortunately, climate and weather scientists have been predicting how conditions are going to
: keep changing in the coming years and decades, and they’ve found that one extra degree
: probably won’t be our stopping point.
: One of the most powerful tools scientists have for making predictions like this are climate models.
: Basically, they take an area of interest — like, a country, or the entire globe —
: and split it into thousands of three-dimensional grid cells that represent the land, ocean, and atmosphere.
: Then, they apply equations based on the laws of physics to those cells to represent how energy and matter
: — like heat and water — transfer between them. So, if you have an extra hot cell near the equator,
: the math will describe how that heat will dissipate into the surrounding cells up into the higher latitudes.
: Then, researchers run millions of calculations, and in the end, the models show how these cells
: — or different regions — will change and interact over time.
: To check how accurate these models are, scientists do something known as hind-casting, where they run
: simulations into the past, and compare the results against historical measurements.
: If predictions for the past are found accurate, it’s likely future predictions will be, too.
: After being tested and refined over and over again, these climate models don’t have the most cheerful news for us.
: Various models forecast that if we keep emitting greenhouse gases at the rate we’ve been going,
: the average global temperature will increase by two degrees Celsius over pre-industrial levels by 2100.
: And because of the way heat is moved around by wind and waves, some places will end up even hotter.
: In the Persian Gulf, where it can already reach 40 degrees Celsius in the summer,
: scientists predict that temperatures will get even higher,
: becoming flat-out intolerable to the tens of millions of people who live there.
: People literally wouldn’t survive outside in the heat.
: The models also forecast melting tundra ecosystems, sea level rise, disrupted ocean and atmospheric circulation,
: and more frequent and intense weather disasters.
: And because of the tricky interconnection of weather across the globe,
: we can also expect extreme cold weather events to become more common —
: more blizzards, more cold snaps, more ice storms.
: And as time goes on, each of these changes will have ripple effects.
: If the planet warms by two degrees Celsius by 2100, average sea surface temperatures
: are expected to rise by a similar amount.
: For as nice as warm water feels when you’re swimming at the beach,
: warmer oceans make it tough for some organisms to survive.
: And while some animals can just try to swim somewhere else, tropical coral reefs can’t move to escape the heat.
: So, they’re predicted to die in huge numbers.
: Scientists think that more than 99% of them could be gone by the end of the century.
: This also means the fish and other animals that call reefs home will die,
: and we would have massive –but preventable– loss in biodiversity on our hands.
: Which isn’t trouble just for the oceans.
: It’s also trouble for the many low-income, coastal communities in places like Kenya and the Seychelles
: that rely on coral habitats for food and income.
: So, if they disappear, these communities will be at risk of becoming more impoverished.
: Where will they get their food?
: And this is just one example of the ripple effects caused by a warming climate.
: You push over one domino, and the impacts are felt way down the line.
: Unfortunately, it doesn’t take a big leap of imagination to see how economic and humanitarian impacts can add up,
: and how they’ll change millions of lives around the world.
: Experts estimate that the global GDP — that’s the total value of the goods and services made by everyone on Earth
: — will actually be lower in 2050 than it is today, even though the population is growing and becoming more developed.
: It’s thought that global productivity will drop by more than 10%, thanks to everything from lower crop yields
: to the loss of infrastructure due to rising sea levels.
: And once that domino falls, so do the standards of living for many people, often worsening pre-existing inequities.
: It’s expected that in South Asia alone — which is an area particularly vulnerable to climate change
: — up to 800 million people will experience a significant drop in their standard of living,
: as higher temperatures affect everything from agriculture to how diseases spread.
: These effects could leave some people unable to afford nutritious food,
: and others with serious illnesses like malaria, in areas that didn’t used to be susceptible to such diseases.
: Similarly, if we keep heading toward a two-degree-warmer world,
: by 2100, sea levels are expected to rise by as much as one meter.
: And because of this, it’s expected that around 630 million people worldwide
: will have to decide whether or not to leave their house, community, state, or even country
: as their homes are drowned or otherwise affected by high tide flooding.
: This will be a decision that people will have to make on an individual, and family, basis —
: a choice between fleeing toward an uncertain future elsewhere… or trying to stay and weather the storm.
: Like we’ve mentioned before, these effects won’t be felt equally everywhere, either:
: Lower-income communities and parts of the world are expected to be the most affected by a warming planet.
: Underscoring the inequity, these areas are often the least responsible for carbon emissions.
: And their systems are the least equipped to deal with the heat, sea level rise, or extreme weather events —
: a.k.a. everything those emissions bring with them. And it gets messier still.
: You see, the Earth and individual climate systems are connected,
: so changes to one affect and exacerbate the other, and vice versa.
: This causes what’s known as a feedback loop.
: For example, as global temperatures increase, they’re melting ice and permafrost in the Arctic.
: And as the ice disappears, it’s releasing huge amounts of the greenhouse gas methane that’s been underground for millennia.
: If all that methane gets out, it’ll mean even faster warming, catastrophic ice melt, and even more methane escaping.
: Basically, if the methane gets out, more methane gets out. A feedback loop.
: Scientists estimate there’s twice as much carbon currently locked away in permafrost
: as there already is in the atmosphere.
: So, the more we release, the faster we zoom toward two degrees and beyond.
: Now, all of this is… well, it’s a tough pill to swallow.
: But it’s not too late to put some brakes on this climate train.
: Some of these effects will be unavoidable, but it doesn’t have to be full-steam ahead to that two-degree-warmer world.
: Climate scientists have evidence that if we pull the emergency brake
: and take major steps to reduce emissions, we could limit warming to just 1.5 degrees Celsius.
: And that half a degree matters a lot. It could help us avoid many of the worst effects of climate change.
: Seas wouldn’t warm as much, saving some coral reefs and the communities that rely on them.
: Dry areas would have fewer issues with water scarcity, and heat waves would be shorter and less deadly.
: And the push for carbon-neutral solutions will help in many other ways.
: Like with climate change itself, cleaning up our act also has ripple effects.
: In countries without reliable access to electricity, the introduction of equitable, renewable energy
: like solar and wind power would help improve healthcare, education, and job opportunities.
: And low-carbon sources of electricity for power and transport also tend to emit fewer pollutants,
: so would help improve air quality in growing urban areas, too.
: It’s the most beautiful, satisfying chain of falling dominos ever.
: And who knows what solutions future generations will bring?
: So, there’s strong evidence that the planet will continue to warm.
: But if you shake your Magic 8 ball and ask it exactly what the future holds,
: it’s probably gonna say something like,
: “It’s up to us.” And we all have a role to play.
: That’s pretty wise stuff from a Magic 8 ball.
: Reducing greenhouse gas emissions now will help reduce some of the worst impacts in the future —
: which is literally life-saving work, for you, for me, for future us.
: And climate action isn’t all or nothing, either. It’s going to be a big task to reach carbon-neutrality by 2050.
: But even if we don’t make it all the way, we can still keep working to limit how much the temperature rises.
: Every half a degree matters and every little bit we can do will improve things for future generations —