Telegraph: Here we go again. On Monday the worlds governments and top climate scientists will publish the most devastating assessment yet of what global warming threatens to do to the planet. And that, in turn, will intensify a new bid to forge an international agreement to tackle it. World leaders will meet in New York in September to address climate change for the first time since the ill-fated 2009 Copenhagen summit. Then they assemble again in Paris in December next year to try once more to conclude a...