The debate is over. There's no time to lose. We must act. By now, pretty much everyone has heard the message from scientists on climate change and it was repeated again today. But are we going to do anything about it?
The latest salvo has come from a week-long meeting of the UN's Intergovernmental Panel on Climate Change (IPCC) in Bangkok, which concluded earlier today.
It follows an IPCC report in February which essentially said: global warming - it's our fault. Today's document takes the more pro-active line: global warming - here's what we can do about it.
The good news is, if you believe the IPCC, the environmental gains can be made without too much economic pain, assuming governments around the world act immediately.
Many delegates were convinced, among them South African environment department official Peter Lukey: "It's all done. Everything we wanted to see was there, and more. The message is: we have to do something now."
That's not only the IPCC's message, but its implied question - is the will available?
Chinese delegates argued strongly against some of the targets for reducing emissions, saying these would harm the country's economic growth. And, as we learned last month, this is the nation about to become the world's single biggest producer of greenhouse gases.
Before we get into another China-bashing session, don't forget that industrialised nations still produce immeasurably more greenhouse gases per head of population than poorer ones, and show few signs of changing their ways.
So is this the tipping point? Or just another moment we'll look back on in 50 years time, as we cling to the top of a tree amid the swirling floodwaters, and sigh: "Well, I guess we were warned"?
