Chinese meteorologists have admitted falling short of public expectations in their failure to forecast the long-lasting drought that has left almost 20 million people thirsty in southwest China, the People's Daily reported Thursday.

"We failed to make precise forecasts on the drought that has lasted so long due to our limited scientific and technological levels," the newspaper quoted Ren Fumin, an official with the National Climate Center as saying.

Ren said it was much more difficult to forecast the climate than predict short-term weather conditions as climate forecasts required more indicators from the atmosphere or even outer space, such as solar activity.

"Our knowledge about the indicators from the outer atmosphere and their relations with climate changes is limited," he said.

"Indeed, climate forecast remains a huge challenge for meteorological departments," said Yu Xinwen, spokesman of China Meteorological Administration. "But we have been working hard on this over the years."

The worst drought in a century has lingered in Yunnan, Sichuan and Guizhou provinces, Guangxi Zhuang Autonomous Region and Chongqing Municipality since September last year, affecting more than 50 million people and leaving almost 20 million people and millions of livestock short of drinking water.