I run a business from polytunnel houses. And I remember when the Japanese tsunami struck, seeing film from the air, like this but moving, of the wave coming in and flattening polytunnel greenhouses in seconds. That moved me as much as anything, since I thought about the people and what they had invested in those tunnels, yes there were far greater tragedies, but if you work in a car showroom it must bring it home to you when you see cars swept away, and if a shop, then when you see a store flattened.

Those are probably high tunnel houses. It extends the season one to two months in each direction. These are becoming much more prevalent near urban areas as it cuts down transportation costs. Plus the vegetables grown are much fresher than being picked greener and shipped in. There are complexes in southern Spain you can see from space that cover square miles.