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化石燃料,包括石油、煤和天然气,是由死亡的有机体和植物在地下分解形成的富含能量的燃料。它们是不可再生的资源,因为人们开采和燃烧它们的速度远远超过新的资源形成的速度。石油储量的减少可能使石油钻探在2050年以后在经济上不可行。 & m" q9 J- u; |" i3 U- v4 g
化石燃料是在几百万年中逐渐形成的,因为海洋和湖泊中的动物、植物和藻类等漂流生物沉降到底部并分解。这些有机物与泥浆混合,沉入越来越深的沉积层下,直到压力和热量将其化学转化为液态和气态的碳氢化合物分子。在陆地上,植物的分解倾向于形成煤和甲烷。
( v& \- U( B' p2 I9 m* ~ 化石燃料是世界上的主要能源来源。每年,化石燃料的燃烧向大气中释放出数十亿吨的二氧化碳。这种温室气体导致全球变暖,这可能在未来释放出毁灭性的气候变化。 0 O' ] {2 r' {( Z
Fossil fuels, including oil, coal and natural gas, are energy-rich fuels formed underground by the decomposition of dead organisms and plants. They are non-renewable resources because people are extracting and burning them much faster than new ones are forming. Dwindling oil reserves might make oil drilling economically unviable beyond about 2050.
8 J2 Y$ h, ~" H" L6 w% I Fossil fuels formed gradually over millions of years as drifting organisms like animals, plants and algae in seas and akes settled to the bottom and decomposed. This organic matter, mixed with mud, sank under ever deeper layers of sediment until pressure and heat chemically transformed then into liquid and gaseous hydrocarbon molecules. On land, the decomposition of plants tended to form coal and methane.
* r# m+ s$ Z, G6 ` Fossil fuels are the worlds primary source of energy. Each year, fossil fuel burning releases billions of tonnes of carbon dioxide into the atmosphere. This greenhouse gas contributes to global warming, which could unleash devastating climate change in the future.
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