BEIJING, Oct. 9(Xinhuanet)-- The summit rock of Mount Qomolangmais 8,844.43 meters above sea level, China's surveying and mapping department announced here on Sunday.

The newly measured height is 3.7 meters shorter than the measurements of 8,848.13 meters, a figure obtained during the previous measurement in 1975, said Chen Bangzhu, director general of the State Bureau of Surveying and Mapping(SBSM).

"The improved technology has made the data of current measurements more precise," he added.

The rate of precision for the measurement of Mount Qomolangma's summit rock is within a margin of 0.21 meter, and the ice and snow layer at the mountain summit is 3.5 meters in thickness, Chen said at Sunday's press conference.

The datum have been obtained after arduous field survey and through thorough calculation and checkout, Chen said.

The SBSM began designing the measurement campaign late last year and Chinese mountaineers climbed up to the summit of Mount Qomolangma at 11:08 a.m of May 22, 2005.

The measurements were then conducted at the six control points by means of theodolites and laser rangers lasting for 48 hours. Surveyors at the mountain summit measured the thickness of the ice and snow layers under the survey marker with radar altimeter.

The datum were sent to SBSM geodetic data processing center in Xi'an, capital northwest China's Shaanxi Province, on June 12.

Mount Qomolangma, located at the Sino-Nepalese, is the highest mountain peak in the world. Enditem