User:ZeinabFashwal/sandbox new
From Wikipedia, the free encyclopedia
My Topic: Coal
Starting my contributions to the article: all my contributions are bolded to distinguish between the content. The non bolded content are copied from the coal article
Introduction:
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. The word originally took the form col in Old English, from Proto-Germanic *kula(n), which in turn is hypothesized to come from the Proto-Indo-European root *g(e)u-lo- "live coal". Germanic cognates include the Old Frisian kole, Middle Dutch cole, Dutch kool, Old High German chol, German Kohle and Old Norse kol, and the Irish word gual is also a cognate via the Indo-European root.Coal is mostly carbon with variable amounts of other elements; chiefly hydrogen, sulfur, oxygen, and nitrogen. (I moved the etymology section to the introduction. It makes sense to have it here rather than a section on its own). Coal is mainly formed from the decay of a big amount of plant material called peat that died and got buried deep down in the sedimentary layer [1] . Coal formation causes the release of gases that escape from coal as it gets compacted. The more compacted the coal is, the more gasses it will release. This phenomena is seen in the sandstones of China [2]
Vast deposits of coal originate in former wetlands—called coal forests—that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian) and Permian times. It was believed that the the evolutionary lag between formation of lignin and its decomposition lead to a huge amounts of plant debris accumulation that resulted in the wetlands and coal formation [3]. However, carboniferous coal formation was dominated by woody trees knowns as lycopsid. [3] (I might remove this section because it is adding a little controversy)
As a fossil fuel burned for heat, coal supplies about a quarter of the world's primary energy and two-fifths of its electricity. Some iron and steel making and other industrial processes burn coal. Despite coals indispensable use in the industrial world, coal does contribute a considerable amount to environmental and humans health problems. Burning coal releases many heavy gases and metals such as carbon and sulfur dioxide that mix with the water and air and lead to hazards like acid rain [4].
The extraction and use of coal causes many premature deaths and much illness. The coal industry damages the environment, including by climate change as it is the largest anthropogenic source of carbon dioxide, 14 gigatonne (Gt) in 2016, which is 40% of the total fossil fuel emissions and almost 25% of total global greenhouse gas emissions. As part of the worldwide energy transition many countries have stopped using or use less coal, and the UN Secretary General has asked governments to stop building new coal plants by 2020. To meet the Paris Agreement target of keeping global warming to well below 2 °C (3.6 °F) coal use needs to halve from 2020 to 2030.