
Science
No, they’re not a mirage — learn how these ingenious ice towers are helping communities preserve water for dry times
Using glacier water and pipes (with a big boost from gravity), Indian engineer Sonam Wangchuk has devised a way to store water in the dry high desert.

Science
Methane isn’t just cow farts; it’s also cow burps (and other weird facts you didn’t know about this potent greenhouse gas)
Why learn about methane? Because it could be our chance to make a real dent in global warming, says environmentalist Fred Krupp.

Science
The worst effects of climate change may not be felt for centuries. So how should we think about it now?
Some argue that we have a moral responsibility for future generations, but others ask: how do we know what they would want? Writer Charles Mann explores the confusing ethics of acting on global warming.

We humans
Opinion: Why the actions of cities — not nations — will be the key to our survival on earth
While some world leaders resist global cooperation, city leaders are working across borders to tackle big issues like global warming, immigration and terrorism, says urban expert Robert Muggah.