Tom Heap asks what the falling price of oil means for the environment.
Tom Heap meets the scientists trying to lessen the impact of volcanic eruptions.
Tom Heap asks if the green belt surrounding UK cities is really green or pleasant.
Tom Heap goes in search of the hybrid beefalo, which is damaging the Grand Canyon.
Bristol is Europe's Green Capital for 2015. Tom Heap finds out what that means.
Iceland is warming faster than most countries. Tom Heap finds out why.
Australia has big plans to develop the Northern Territory. Julian Rush reports.
The melting sea ice of the Arctic creates opportunities and threats. Tom Heap reports.
Tom Heap investigates the theft and smuggling of rare flowers and its impact.
Tom Heap meets a man who can turn dirty water into clean, drinkable water.