Acid rain,global warming, polluted rivers, species loss, deforestation, falling sperm counts, desertification - everywhere the world seems to be going to hell in a hand cart and only radical changes in our lives and major population reductions can halt the decline. At least that's what he mainstream green groups tell us. But former Greenpeace member and Danish academic Bjorn Lomborg says that's a load of old tosh; environment is doing much better than ever before, he says...editorial