I suspect a lot this year is down to the extremely pronounced El Nino effect although there's some research which suggests overall warming is aggravating that, too. The planet's atmosphere is warming - that's been established beyond doubt. It's still not entirely clear what's mainly responsible. One notable irony is that when, in 1987, we replaced the Ozone depleting CFCs with HFCs in refrigeration equipment the Ozone hole gradually healed itself, but HFCs, like CFCs, are inert gases that make good coolants in refrigeration systems and propellants in aerosols. But molecule for molecule, some HFCs are up to 10,000 times more potent than carbon dioxide as greenhouse gases, according to the UN Environment Programme (UNEP). So we've been adding potent greenhouse gases to the atmosphere for 30 years on a massive scale and are only now starting to do something about it.