Giving Compass' Take:

• The Climate Reality Project explains that the 1.5 degrees Celcius threshold for climate change is a rough boundary between destructive and catastrophic climate change. 

• How can funders work to keep the climate within this boundary? 

• Learn how to accelerate progress against climate change. 

When we talk about 1.5 degrees of warming, we’re talking about the increase in the Earth’s average temperature. We measure this increase from a baseline average temperature in the mid-to-late nineteenth century – when the Industrial Revolution swung into high gear and people began burning fossil fuels on an unprecedented level, jumpstarting climate change.

The important thing to understand is that global warming that comes from burning fossil fuels is not a uniform process. Due to a host of natural factors, some areas – like the poles – are warming much faster than others. So when we talk about preventing 1.5 degrees of global warming, we’re talking about preventing a 1.5 degree increase in the Earth’s average temperature. Some places have already crossed that line.

Global warming reaching 1.5 degrees doesn’t mean that average temperatures in some places won’t rise significantly beyond that number. Again – it’s just the global average.

Then there’s the fact that as average temperatures rise, spikes and heatwaves will go much, much higher than just 1.5 degrees.

As the Intergovernmental Panel on Climate Change (IPCC) – basically the gold standard for climate science – reported: “Several regional changes in climate are assessed to occur with global warming up to 1.5°C compared to pre- industrial levels, including warming of extreme temperatures in many regions.”

“If global warming reaches up to 1.5 degrees, the hottest of the hot temperatures will increase and many (more) places will get dangerously hot.”

We got a preview of what “extreme temperatures in many regions” looked like in 2018.

about 1.5 degrees of global warming is right about where there’s enough heat to push many of the natural systems that sustain us past a dangerous turning point.

Think of 1.5 degrees not as an absolute line in the sand, but as a general indicator of where many climate impacts – on balance – go from destructive to catastrophic. It’s the sign on the door that leads to somewhere very dark indeed, somewhere no one wants to go.

Read the full article about holding climate change to 1.5 degrees Celcius at The Climate Reality Project.