With all our cars, air conditioners and electric appliances, it is impossible to live in a city like Hong Kong without producing carbon dioxide every day. Modern living relies heavily on fuels. Even if we're careful to use as little as possible, we'll still add more carbon dioxide to the environment than is ideal. This is called our carbon footprint. But there is a way to balance our role in climate change. It's called carbon offsetting, and it's a pretty simple idea. To offset your carbon output, first measure how much carbon dioxide you are producing.
There are many tools on the internet that can measure the impact of driving a car, taking a flight to Europe or buying a new piece of clothing. Here's one: footprint.wwf.org.uk/
Once you know how much carbon dioxide your activity produces, you can pay to reduce the same amount elsewhere.
Let's say using my car for one month produces one tonne of carbon monoxide. I buy carbon credits for one tonne. The company that sells these credits invests my money in a wind turbine that creates clean electricity. Or it plants trees, which absorb carbon dioxide and make the air cleaner.
The one tonne of carbon dioxide I have produced means I have contributed to global warming. But buying carbon credits helps me pay for that environmental damage. It's a simple idea. Many big companies buy credits to make up for the damage they do to the earth. Airlines offer carbon credits as an option when you buy your flight ticket. They help you calculate how much carbon your share of the flight produces, and then give you a chance to offset it through buying credits.
Such carbon-offsetting programmes succeed in doing one very important thing. They force us to think about our carbon emissions in terms of money. Now we know the cost of our personal energy use, it's up to us to do something about it.