Chinese surnames are used by Han Chinese and Sinicized ethnic groups in Mainland China, Hong Kong, Macau, Malaysia, Taiwan, Korea, Singapore, Vietnam and among overseas Chinese communities. In ancient times two types of surnames existed, namely xing (Chinese: å§; pinyin: xÃ¬ng) or lineage names, and shi (Chinese: æ°; pinyin: shÃ¬) or clan names.
An ice sheet is a large permanent layer of ice covering a continental shelf, defined as having an extent greater than 50,000 km2 (19,305 mi2). An ice sheet is larger than a glacier or ice shelf.
The Greenland ice sheet covers roughly 85% of the land surface of the island and rises to an average height of 2.3 km (1.6 miles). The immense weight of the ice sheet has pushed the center of the island roughly 300 meters (1000 ft) below sea level. The icy expanse of Greenland, like the rest of the Arctic, not only represents an important climatological indicator, it also is critical to future global climate. Were all of Greenland's ice to melt, global sea level would rise 7 meters (23 feet).