These deep, kilometres-wide channels, known as tunnel valleys, were cut by fast-flowing rivers that ran under Northern Europe's ancient ice sheets. Read more on BBC.
To avoid the worst consequences of climate change — worsening extreme weather, irreversible ecosystem shifts, loss of life and economic hardship — scientists say the world must limit global warming to 1.5 degrees Celsius above pre-industrial levels. The only way to do that, they say, is by making deep cuts to fossil fuel emissions. Read more on CNN.