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.
Virtually all the ice on Earth's surface and in its atmosphere is of a hexagonal crystalline structure denoted as ice Ih (spoken as ice one h) with minute traces of cubic ice denoted as ice Ic.