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7 key facts on climate change

This article covers 7 key facts on climate change, why action from companies is critical, and how to do more to convince others.
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David Wallace-Wells’ book “The Uninhabitable Earth”, is an incredibly well-researched book with some alarming facts. Most of you will be reading this because you are looking to make a difference in the fight against climate change. But if you need support in convincing others to help you on this journey, then some of these facts can be a great place to start.

1. Most scientific models show us heading for between 2 and 8 degrees of warming by 2100

We then enter what some scientists refer to as “The Century of Hell”1. 2 degrees is conservative and the current target for those signed up to the Paris Agreement (for which no country is on track to meet their targets). 8 degrees is equally unlikely, which is good news because that’s an extinction-level event.

2. The conservative rise of 2 degrees would see 150 million additional deaths from air pollution issues alone. 

That’s twice as many as died in World War II2. And remember, limiting to “only” 2 degrees seems unlikely at this point. Also, that’s additional deaths caused by going above the original 1.5 degrees of warming, not the total.

3. Every 0.5 degree could see a 10% to 20% rise in armed conflict.

Due to scarcity of resources and climate refugees from poorer parts of the world (which are ironic, given their very low emissions per person, going to be the worst hit by climate change initially). The perfectly realistic models of 3 to 4 degrees of warming in the next 80 years means we could be living in a world with 50% more armed conflict than we have today3.

4. Models show that 3.7 degrees of warming could cause global damages of $551 trillion.

That’s nearly double the current global wealth4.

5. On our current trajectory, the UN projects 200 million climate refugees (many from the Middle East and Africa) by 20505

Remember that Europe faced significant problems dealing with “only” 1 million refugees caused by the conflict in Syria in 2011.

6. Of the 5 mass extinction events in the last 450 million years, 4 of them were climate-related.

250 million years ago a 5-degree rise triggered the release of methane which caused a significant feedback loop. We are currently adding carbon at 10 times the rate of that event6.

7. With around 200 species becoming extinct every 24 hours.

(Over 1000 times the “background rate”) many scientists claim we are already in the 6th extinction event (known as the Holocene extinction event).

This is a human-made crisis. There is a lot of nonsense around, including “facts” like volcanoes producing more emissions than humans (in fact they produce only 1% of emissions compared to human activities at around 0.3 billion tons per year compared to our 29 billion tons).

Nothing else, no natural events, can explain the exponential rise in CO2 since the dawn of the industrial age and the associated rapid rise in global temperatures. It’s not sunspots or solar cycles driving this naturally either.

This was made even clearer in the IPCC’s climate report, released in August 2021. According to Prof Ed Hawkins, from the University of Reading, UK, and one of the report’s authors, the scientists cannot be any clearer on this point.

“It is a statement of fact, we cannot be any more certain; it is unequivocal and indisputable that humans are warming the planet.”


1 – “Century of Hell”: Brady Dennis and Chris Mooney, “Scientist Nearly Double Sea Level Rise Projection for 2100, Because of Antarctica,” The Washington Post, March 30, 2016

2 – “150 million people”: Drew Shindell et al., “Quantified, Localized Health Benefits of Accelerated Carbon Dioxide Emissions Reductions”, Nature Climate Change 8th March 2018, –291-95

3 – “for every 0.5 degrees of warming”: Solomon M. Hsiang et al., “Quantifying the Influence of Climate on Human Conflict”, Science 341, no. 6151 (September 2013)

4 – “$551 trillion in damages”: R. Warren et al. “Risks Associated with Global Warming of 1.5 or 2C” Tyndall Centre for Climate Change Research, May 2018

5 – “U.N. Projections”: Baher Kamel, “Climate Migrants Might Reach One Billion by 2050” ReliefWeb, August 21, 2017

6 – “at least ten times faster”: “Maximum rates of carbon emissions for both the PETM and the end-Permian are about one billion tons of carbon, and right now we’re at ten billion tons of carbon” the Penn State geoscientist Lee Kump, among the world’s leading experts in mass extinctions in an interview with David Wallace-Wells, Author or The Uninhabitable Earth

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