SHANGHAI -- With Typhoon Kaemi roaring toward China's crowded southeast, Dr. Yang was sealing his apartment windows against the pounding rain when his cellphone buzzed to life.
``Typhoon forecast to make land this evening," said the message sent to millions of mobile phones in the coastal city of Jinjiang and surrounding Fujian province. ``Please attend to preparations."
Text messages have become a key tool for Chinese authorities during this year's unusually powerful typhoon season.
Nearly one-third of China's 1.3 billion people has a cell phone, creating a rival to television and radio as a way to reach the public.
Authorities in Fujian have sent 18 million messages -- known as SMS, for short message service -- with storm information during five typhoons this year, according to the provincial government.
Although residents complained of poor execution, many praised the idea of using text messages to send storm warnings.
``Technology is improving, and I think the government sending messages to warn of natural disasters is pretty smart," said Dr. Yang, who works at Jinjiang's Chinese medicine hospital and would give only his surname.
China's population of cellphone users -- the world's biggest -- long ago surpassed the country's 365 million fixed-line phones, and is growing rapidly.
Cellphone use has spread from affluent urbanites to fishermen, blue-collar workers, and farmers in the countryside. It isn't unusual to find villages with no fixed lines but dozens of cellphone customers.
Chinese cellphone carriers have built a nationwide network with such extensive coverage that phones work in places as far flung as the Tibetan plateau and the northwestern deserts.