Paris (AFP) - If mankind fails to curtail global warming, we will have to deal with fallout ranging from massive refugee crises and submerged cities to scorching heatwaves and drought, scientists say.
Starting on November 30, 195 nations will huddle in Paris for a climate rescue pact to rein in the greenhouse gases that drive climate change.
Here is what could happen if they come up empty handed:
Without additional action, Earth could heat up by as much as four degrees Celsius (7.2 degrees Fahrenheit) by the end of the century, compared to pre-industrial levels.
A mountain of scientific evidence tells us this would be a recipe for disaster.
A "business as usual" emissions scenario would "lead to a very high risk of severe, widespread and irreversible" impacts, according to the UN Intergovernmental Panel on Climate Change (IPCC).
By 2100, the world's oceans would rise 26-82 centimetres (10-32 inches) over levels seen between 1986-2005, the IPCC found in its most recent assessment, which includes data up to 2012. More recent studies suggest the increases could be even higher.
Driving the rise are ice sheets in Greenland and Antarctica shedding mass faster than ever, melting glaciers, and oceans that expand as they warm.
Even a 2 C rise as targeted by the UN would submerge land currently occupied by 280 million people, according to Climate Central, a US-based research group. The change could take a few hundred years, or up to 2,000 years.
Superstorms, bone-chilling cold snaps and intense heat waves could become more common -- and more extreme -- due to global warming.
While the link between specific weather events and climate remains hard to nail down, recent research has teased out climate change as an aggravating factor for deadly floods, snowstorms, typhoons and heat waves.
Not all nasty hurricanes or heat waves, however, can be chalked up to climate change, scientists caution.
Global warming can lead to long-running droughts and devastating floods, which means some parts of the world will not have enough water and others too much.
Droughts in Syria and California have been tied to climate change. Heavy rains carry the risk of flooding that can send people fleeing for their lives, destroy homes and crops.
Global warming can spur disease, ravage crops and push more people into poverty. Conflict over water or smaller harvests could instigate war or mass migration.
People living on low-lying islands such as the Maldives, an archipelago in the Indian Ocean, or the Philippines could become climate refugees, forced to flee their homes due to rising seas.
Impoverished people in the world are already being hurt by heat waves, drought and flooding, because they are both more dependent on the land and lack public services.
The warring inhabitants of Westeros — one of the four known continents in the Game of Thrones world — dread the planet's long, unforgiving winters. But a global warming event there, stoked by an influx of carbon dioxide into the atmosphere, would likely be even more dire.
Earlier this week, University of Bristol climate scientist Dan Lunt published a study that modeled the doubling of carbon dioxide on the Game of Thrones fantasy world. His results show that if these levels doubled over the course of a century, the average temperature on the planet would warm by over 2 degrees Celsius, or about 3.5 Fahrenheit. This climatic shift would make some areas nearly uninhabitable and unleash devastating natural disasters.
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"When you kick the climate, every single part of it changes," said Lunt in an interview. When not modeling the future climate of fantasy worlds, Lunt researches the mechanisms that influenced past climate change on Earth to better learn how future atmospheric changes will affect our planet.
Lunt notes his work is "relevant for Earth's policy makers as we burn more fossil fuels."
Image: Dan Lunt / University of Bristol
Lunt said it's "not a giant leap to simulate climate change in a fantasy world." The two degrees of simulated warming here — as carbon dioxide gases trap a nearby sun's reflected heat inside the world — would bring about extreme events like heavy rain, flooding, storm surges, and drought in different regions around the medieval-themed planet.
"Normally when you double the amount of CO2 then you tend to increase extreme events," explained Lunt. "The system is so interconnected that every thing changes."
An important consequence of this warming for the peoples of the Seven Kingdoms would be thawed polar regions, which in the north is home to the murderous White Walkers — malevolent, supernatural humanoids that can only survive in frigid climes.
"It's a big change, especially the effects it would have on the White Walkers," said Lunt. "It would push them back further north."
For people of Westeros, this is outwardly a good thing. The White Walkers — whose primary motivation seems to be annihilating people — would be sequestered far away in near the north pole.
But, notes Lund, "There are winners and losers in climate change." For instance, the southern land of Dawn "would probably become uninhabitably hot," he said.
Image: DAN LUNT / UNIVERSITY OF BRISTOL
The ornate castles and infrastructure of King's Landing — home to spiteful Cersei Lannister — also wouldn't be spared.
"King's Landing would be struggling in terms of sea level rise," Lunt said.
Modeling a planet with only four known continents is no easy task. Fortunately, there are at least good maps of the known fantasy world, and the Game of Thrones books reveal what areas lie near the center, or equator. From here, Lunt was forced to make up other continents as he lacked any better options.
Lunt also only had time to run the models for a century — so the warming effects could certainly have increased had more time passed, bringing more natural terror to the Seven Kingdoms.
After the models were finished, there seemed to be few places that were desirable to live. When asked where he might reside in such a climate-ravaged world, Lunt replied The Neck on the Westeros continent, where nearly the entire Stark family was murdered in a surprise bloodbath.
"It looks nice there," he said.
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