Volcanic Nanoparticles - How do volatile metals from volcanoes end up in polar ice cores? It has always been a mystery how trace metals, like mercury, with a volcanic signature find their way into polar ice in regions without nearby evidence of volcanic activity. Now scientists think they have discovered the answer - volcanoes are a source of tiny nanoparticle which could be involved in cloud formations and seeding the oceans with nutrients. And also on the programme Seawater Greenhouses. The world is running short of accessible fresh water. Agriculture uses 70% - but now a team comprising an inventor, an architect and an engineer have proposed a new technology – the Seawater Greenhouse -that could produce food, fresh water and clean energy in arid regions as well as re-vegetating large areas of desert. As the name suggests – it uses seawater to do it. Less