To The Ends Of The Earth

Scientists are going to extreme lengths to find out how climate change is affecting our planet

- Dr Helen Pilcher

FAIRWEATHER FRIENDS

ST HELENA, SOUTH ATLANTIC OCEAN

Every day at 11:15 am, a team of meteorologists on the Atlantic island of St Helena release a giant latex weather balloon into the sky (previous page). They wear goggles, flash hoods and overcoats ‘just in case’ because the balloons are full of highly explosive hydrogen (this lighter-than-air gas causes the balloon to ascend). As the balloon rises to a height of more than 30km, a mini weather station or ‘radiosonde’ attached to the balloon’s neck sends back second-by-second information on temperature, humidity, wind speed and pressure. St Helena’s meteorological station (part of which is seen in the image below, being tended by the station’s technical manager Marcos Henry) is one of 190 such stations worldwide monitoring the Earth’s upper atmosphere of the Global Climate Observing System. Conditions here are tricky: strong winds buffet St Helena, and its remote location 2,000km off Africa’s southwest coast means that imported goods are pricey. But stations such as this one play a crucial role in monitoring the long-term changes in our climate system.

A SLICE OF TIME

GEPATSCHFERNER GLACIER, AUSTRIAN ALPS