If a key ocean current collapses it could plunge northern Europe into a big freeze. Now researchers are weighing up a drastic intervention – building a 130-kilometre-wide dam between the US and Russia

The US Department of Defense has released hundreds of documents and photographs related to UFOs, some of which have been declassified, in the first of many drops to come

Many flowering plants have duplicated genomes, which could have helped them evolve to deal with extreme stress in times of environmental upheaval

A drone has crashed in the Chernobyl exclusion zone, causing a fire that has spread to 12 square kilometres of land. Dry weather, strong winds and the presence of land mines are complicating efforts to bring the blaze under control

Satellite measurements show that in the early 2010s sea level rise suddenly accelerated to a rate of 4.1 millimetres per year, possibly in response to an increase in the rate of global warming

How important is thinking about your breath for calming yourself down? We now know that slow breathing is effective even without conscious involvement