It’s November already. Normally, this is the time to say goodbye to summer clothes and chase after the autumn-winter fashions. But it’s common to see girls and boys in vests and short pants walking around our campus. So where is the chill? Suddenly, the temperature has dropped to 17 degrees Celsius during the day of 3 November 2009, when I am writing this article. When I thought my lovely summer was leaving, and the chilly winter would come anyway, I read a piece of weather news saying that the cold days in Hong Kong will just last for three days and the warm days will come back at the end of the week. What’s more, Hong Kong will have an exceptionally warm winter this year. That means the warm winter is going to re-visit us after 2006.  In fact, the so-called El Nino, literally "the Baby Jesus”, which is a periodical natural phenomenon that causes the usual weather, will appear in December this year.  Scientific evidence shows that El Nino is affected by the global warming, according to Science Daily. Meanwhile, the global warming effects are caused by the greenhouse gases that we produce. I am not fond of chilly winter days. But I will have mixed feelings when we cannot feel the chill of winter as we used to. Can you imagine: you have to put aside your beautiful winter clothes for a very long time, you cannot enjoy hot-pot food as you usually do with friends in the winter, you need to spend more on turning on your air-conditioners for cool air.  It will be sad if we lose the opportunities to do the usual happy things that we are supposed to do during the cold winter time. However, as the traditional saying goes, it’s never too late for a change. What we need to change are the bad habits that we follow in our daily lives: wasting energy, using non-environmentally-friendly products, being indifferent to the weather changes in our environment, and so on. image form ( http://www.eedu.org.cn)