A Very Large Hole in the Sahara

Scientists are looking at novel ways to halt sea-level rise and reverse global warming, but not the way in which Miranda Krestovnikoff is attempting to do her bit on Exmouth Beach...One idea proposed was to flood lowing lying parts of the planet - parts of the Sahara desert in order to accomodate rising sea level caused by global warming and the melting of ice-sheets and glaciers. An idea quickly dismissed by climate scientist Tim Lenton who joins Miranda on the beach as she attempts to empty the water from the ocean.Futuristic visions of the sky filled with trillions of tiny mirrors and giant man-made clouds over the oceans to reflect the power of the sun are just two ideas scientists have come up with in their quest to make a giant sunscreen for the planet and to try and cool the climate.And just next month a team of scientists from universities in the UK are carrying out an experiment to see if they can hoist a giant hosepipe one kilometre into the air. If successful they will attempt to upscale the experiment. The aim is to see if they can extend the pipe up to 20km should they ever need to spray aerosol particles into the air to recreate the effects of a volcanic eruption. Matt Watson leads the project and he explains how successful Mount Pinatubo was in lowering the earth's temperature for two years after it erupted.Miranda Krestovnikoff investigates which futuristic geoengineering concepts could become a reality if we continue to fill the atmosphere with greenhouse gases and what impact messing about with the climate could potentially have on weather systems across the globe.