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.
Polar ice caps are high-latitude areas completely covered in ice that occur in the polar regions of Earth. Other planets, Mars for example, have polar ice caps also, but unlike Earthâs ice, which is largely composed of frozen water, Marsâ ice is mostly made up of frozen carbon dioxide. Polar areas receive less solar energy from the sun and are therefore subject to low surface temperatures, allowing ice caps to form.