Planet Earth

Scientists know that fluffy stratocumulus clouds act like a blanket on the Earth - they stop warm air escaping, but also reflect the Sun's energy back out to space. But they have no idea if cirrus clouds, which are high up in the atmosphere and made of ice, do the same. So Dr Paul Connolly makes ice clouds inside the 10-metre-high, three-storey ice cloud chamber - which looks a bit like a giant fridge freezer - to find out. To hear how the chamber works, Sue Nelson goes to Manchester to meet him. Also in the programme, find out how a tiny wasp, just 1.5 millimetres long, can pollinate fig trees 160 kilometres apart. And after the successful launch of the European Space Agency's Soil Moisture and Ocean Salinity (SMOS) satellite earlier this month, Professor Meric Srokosz from the National Oceanography Centre, Southampton, tells us why he's pinning his hopes on the data. Finally, Richard Hollingham gets more than he bargained for when he visits the venomous snake facility at Bangor University.