(Science Week, day 6!)

Justin Rowlatt for the BBC:

Renewable energy overtook coal as the world's leading source of electricity in the first half of this year - a historic first, according to new data from the global energy think tank Ember.

This must be a difficult thing to study, but the BBC felt comfortable making the claim in the article's headline, so let's suppose it's true.

We know a few things about the climate situation. Humans and what they do emit a lot of greenhouse gases, particularly carbon dioxide; greenhouses allow light to pass into them and trap the heat inside. In short, the planet's atmosphere acts somewhat like a real greenhouse, just slightly enough to slightly raise the temperature everywhere. That means a little more ice melts, a little more water rises, a few more fires start (sending up yet more greenhouse gases), and this all influences the movements of air and water above sea level.

The burning that emits greenhouse gases is a source of energy; for example, we can move vehicles or get electricity from it, and the study adds that humans are using more of that than ever.

The alluded good news is that the sun is itself a practically endless source of energy, and capturing and using solar energy doesn't send greenhouse gases into the sky. The wind already blowing around the earth is another source.

This supposed lead gained by renewable energy presumably isn't enough to relax our effects on the atmosphere, but most everything that goes big starts small.

• BBC article