September 24, 2007 10:17 AM
Typhoon Wipha marked a turning point in the perception of extreme weather events.
The past year has seen several milestones in government acknowledgement of the effects of climate change. In April, China released a report on the effects of climate change [PDF], forecasting an increase in droughts, floods and desertification, and a decline in agricultural output. And at a press conference in August, China Meteorological Administration official Song Lianchun connected this summer's increase in floods, droughts and heat waves to climate change.
Last Tuesday, as Wipha neared Shanghai, People Online (the People's Daily website) and China Meteorology Times co-produced a video in which Central Weather Station deputy director Bi Baogui echoes the connections made by Song. A transcript is here.) Here's a rough translation of key parts:Host: Can you tell us a little bit about what's special about the typhoons that have touched down in our country in September?
Bi Baogui: The overall characteristics of this year's typhoons -- up to now, there have been 13 typhoons. Looking at the entire year, on the whole the number of typhoons is relatively low. But...these typhoons have been very active. To look at the influential typhoons, there have been four that have affected our country, either by passing through Japan or by touching down in our country. It should be said, going into September, that overall typhoon intensity has been extraordinarily strong....From June of this year until now, overall [atmospheric] circulation has in fact been abnormal. For example, this year the Huai River rose to cataclysmic levels not seen since 1954. When that was over, on the upper reaches of the Yangtze, Chongqing, which last year experienced drought, saw the biggest floods in years...Overall, this year's weather has been extraordinarily abnormal....
Host: You're an expert. What do you think is causing this sort of serious climate change?
Bi Baogi: It should be said that this sort of big change in events, first of all it has intrinsic causes. At the same time, we can't rule out external factors. Global temperatures are rising -- since 1849, overall temperatures have steadily increased. And after temperatures increase, to give an example: if you drop a tea egg in cold water, it won't get hard. It only gets hard when you put it in boiling water. To use this example, after surface temperature increases, it's possible that instability rises -- and as instability rises, the probability that this sort of extreme weather event will occur goes up.In other words, while it's difficult now to link every single climate change to a specific event, if you look at it from the macro level, as overall temperatures rise, instability increases, and this sort of extreme weather event increases, causing changes in atmospheric circulation.