Frustrated at the blame shifting and calling for global action. Climate change is one area his govenment had a reasonable record. They put in place many policies to promote better emmissions, subsidise alternative energy and efficiency. They missed a couple of targets they publicy set themselves, but did make good progress towards them.
The Tories pretty much scrapped the lot the moment they got in power and are now full speed ahead trying to force fracking as the future. In locations far enough from London to not care tuppence about.