There are 8 billion people on Earth. But that isn't causing climate change, scientists say

As It Happens6:44There are 8 billion people on Earth. But that's not behind climate change, scientists say

With Earth's population hitting a projected eight billion, it's easy to draw the conclusion that climate change is the result of too many people consuming energy.

But scientists say it's not that simple. Climate change, they say, is more a matter of overconsumption than overpopulation. And there isn't a neat correlation between between the two.

"As a climate scientist, I know that it's not the number of people that matters. It's how we live," Katharine Hayhoe told As It Happens host Nil Kksal.

Hayhoe, chief scientist at the international environmental organization Nature United, says there's plenty we can do to fight climate change. But reducing the global population isn't a key component.

"We know that this planet can carry eight billion people, but not if they all live like Canadians. We need to be more efficient with our energy," she said.

"We need to accelerate the transition to a clean energy economy. We need to engage in climate-smart agriculture. And we need to remember that we are not only a citizen of this country; we're a citizen of the world, and we all share this home."

Population and emissions don't go hand-in-hand

Hayhoe's arguments are echoed by many of her peers some of whom have changed their tune over the years.

The Sierra Club, for example, is an an environmental non-profit thatused to promote efforts to control the world population.But they shifted gears when they looked more closely at the science, the group's president, Ramon Cruz, told The Associated Press.

He said when they dived deeper, they found problems of overconsumption and fossil fuel use would be the same "at six billion, seven billion or eight billion" people.

Climate Interactive, a group of scientists who run intricate computer simulations, came to a similar conclusion.The group compared United Nations population projections scenarios of 8.8 billion people and 10.4 billion people, and found only a 0.2 degrees C difference.

But the difference between having no price or tax on carbon, versus taxing it at$100 US, a ton was 0.7 C.

"The question is not about population, but rather about consumption patterns," climate scientist Bill Hare said.

The key to understanding climate change, scientists say, is to look at who is consuming the most and who is suffering because of it.

For example, many of the countries with the fastest growing populations are in Africa. Yet, those same countries are facing the brunt of the climate crisis.

According to The Associated Press, Africa has 16.7 per cent of the world's population, but historically emits only threeper cent of the global carbon pollution. The United States, on the other hand, has 4.5 per cent of the planet's people, but since 1959, has put out 21.5 per cent of the heat-trapping carbon dioxide.

The average Canadian, Saudi and Australian, meanwhile, put out more than 10 times the carbon dioxide into the air though their daily living than the average Pakistani, which has experienced massive and deadly floods that have been linked to climate change.

"It is the rich, industrialized, high-emitting countries that are largely responsible for this problem," Hayhoe said. "Not only countries, though. Companies [and] cities as well."

Loss and damages

Hayhoe spoke to CBC as she was leaving Egypt, where she was attending COP27, the UN's global climate change conference. She says not enough has been done to combat climate change since last year's conference.

"Since the Glasgow COP a year ago, there has been over $6 trillion worth [in] U.S. dollars in subsidies to the oil and gas industry," Hayhoe said. "We know that something has to change."

The issue of inequality has been front and centre at COP27, she said.Many of the climate activists in attendance are calling for an international agreement based on the concept of "losses and damages."

That means the world's biggest emitters both countries and corporations should fund climate change mitigation efforts in the nations most affected by it.

"It's simple.... If you are the one hurting something, it's your responsibility to fix it," Indian climate activist Disha Ravi told As It Happens from COP27 on Friday.

"So here, when we ask them to give us climate financing, we ask them to give it to us in the form of loss and damages finances adaptation funds, mitigation funds. It is to ensure that we are in a place where we can actually, not just survive, but have a livable present and a future."

But figuring out who should pay what could be a complex and tense process, reports CBC News's Chris Brown. For example, China is currently the word's greatest emitter of greenhouse gasses. But historically,no country has emitted more carbon than the U.S.

Canada has said it's open to discussing loss and damage funding. Hayhoe says it's a concept that reflects the fact that "climate change is profoundly unfair," and she hopes itbe reflected in any new international agreements.

"I've spoken with so many people and heard so many stories of people who come from islands in the Caribbean where they're facing drought and warming seas and depleting fisheries. Or Bangladesh, where they're facing repeated floods and then droughts," she said.

"If it [a loss and damages agreement] doesn't come, what does that say to those countries? It says we don't care. We don't even think that you share the same planet. It doesn't matter to us what's happening to you."

But despite the uneven effects of climate change, Hayhoe warns that nobody will emerge from this crisis unscathed.

"There's no way to build walls up to the top of the atmosphere around our country or any other country to protect ourselves from climate change while the rest of the world suffers," she said.

"We all share this home together, and we know the science is clear. The faster we reduce our emissions, the better off we will all be."