The challenge of tackling climate change is so huge that relatively small cities like Hong Kong may mistakenly think only large nations need to act. Our officials point out that Hong Kong, with its low per capita carbon emissions, is not among the worst culprits. Under China's Kyoto Protocol obligations, Hong Kong is not obliged to cut emissions of the greenhouse gases that accelerate global warming. So we have taken the softer option of doing our best to enhance energy efficiency. Given the gravity and urgency of the situation, we need to do much more. We are a coastal city with millions of people and billions of dollars of assets. The Observatory has just sharply increased its end-of-century temperature forecasts, describing climate change as 'a matter of life and death'. We need to demonstrate true 'world city' thinking on this issue and we need a government that will lead today, not 'The Day After Tomorrow'. There have been piecemeal initiatives in the right direction with government efforts to make energy efficiency labelling and building energy codes mandatory, with use of gases from landfill and sewage treatment, planting of trees and a plethora of 'green' projects in government buildings. But this is hardly taking the bull by the horns. While cities such as London already have climate-change plans, Hong Kong is about to commission yet another study on its impacts and mitigation that will take two years. We do not have a clear picture on what is the best energy mix for Hong Kong. Despite the efforts of think-tanks, green groups and some legislators, we do not have a serious debate going on whether Hong Kong, as a responsible global citizen, should step up to the plate, set its own targets for emissions reduction and make them mandatory, even if it means paying more for electricity. Like many other societies, we seem reluctant to confront the realities of the coming carbon-constrained world and the lifestyle changes it will inevitably bring. We are still building roads for yet more private vehicles. While keen to create a better Hong Kong for our children and grandchildren, we have not yet contemplated life for our great-grandchildren sweltering in Hong Kong's endless summers of the 22nd century. All this is potentially rich pickings for the Climate Change Business Forum that will be launched today. The inaugural membership is significant both in terms of major Hong Kong companies that have joined and also for those heavyweights that are - as of now - missing. The forum aims to provide a leadership platform 'to address the opportunities, risks and expected regulations associated with emission reduction'. It also plans to fund research on climate-change impacts and communicate its findings. Its leader, Executive Council convenor Leung Chun-ying has already called for the government to set itself a target in reducing emissions. The issue will be whether the forum is prepared to go further and back mandatory targets, or risk becoming another talking shop. Hong Kong has shown before that it can get ahead on the toughest issues of the era. We did it with public housing in the 1950s. We did it with corruption in the 1970s. It is time for Asia's world city to demonstrate leadership and a global vision on climate change before more glaciers melt.