Conversation took a turn for the worse at a dinner party I was at recently, when the guests began to boast about their environmental credentials, each claiming to be greener than the others.
One described how she diligently separates and recycles her rubbish. Another had volunteered to go planting trees on Lantau. A third related how he had spent a small fortune installing a solar water heater on the roof of his New Territories house.
In truth, none of the guests that evening could claim to be even remotely green. As well-heeled professionals with regional responsibilities and international backgrounds, they all spend much of their working lives flying around Asia, and each is happy to hop on a plane for a weekend away or for a longer vacation in Europe or the United States.
That penchant for air travel completely negates all their other efforts to go green. My own carbon footprint illustrates why. According to the emissions calculator at Climateers.org, at home and at work in Hong Kong, I'm responsible for pumping out about 10 tonnes of carbon dioxide a year. But factor in a couple of long-haul flights and a few trips around the region, and my emissions shoot up to 30 tonnes.
So if I or any of the other guests that night really wanted to go green, by far the most effective thing we could do would be to give up flying, or make sure that we offset the greenhouse gases emitted by our flights. In truth, we just talk about our concern for the environment, but we don't actually do anything to cut our emissions.
As with dinner party guests, so with governments around the world. It's only a few weeks since governments promised in Durban to devise a new treaty to reduce global emissions.