XINING, May 5 -- The surface area of China's largest inland saltwater lake has expanded over the past decade, as rainfall increases and temperatures rise, northwest China's Qinghai provincial weather bureau said Tuesday.

The surface area of Qinghai Lake on the Qinghai-Tibet Plateau was recorded at 4,389.31 square kilometers, an increase of 9.08 square kilometers from last year, and the tenth consecutive annual increase, according to Liu Baokang of Qinghai Institute of Meteorological Science.

Winter was comparatively wet this year, and warmer than usual, bringing more snow meltwater into the lake, Liu said.

Qinghai Lake plays an important role in the ecological security of the Qinghai-Tibet Plateau. The lake had been shrinking since the 1950s, but the combined effects of conservation and changes to the regional climate turned things around in 2005.