< p >“化石燃料”是一个灰色地带。大量的碳酸盐岩不充分燃料。还有很多深层页岩可能被认为是化石燃料不可能使用的,因为它太难以到达,尽管它可以水力压裂和可以使用它的百分比。< / p > < p >同时,化石燃料需要的消耗(使用)的速度,这可能会失控的全球变暖是不确定的,但可能是巨大的。也许数量级高于当前projecte消费率。维基百科的文章< a href = " https://en.wikipedia.org/wiki/Runaway_greenhouse_effect Distant_future”rel = " nofollow noreferrer " >失控的温室< / >表示:< / p > < blockquote > < p >随着太阳变得亮10%约十亿年的时间,地球的表面温度将达到47°C (117°F),导致地球的温度上升迅速,海洋沸腾,直到它变成一个温室行星类似于今天的金星。< / p > < /引用> < p >目前地球表面平均温度约16°C, 50年前,大约15°C。甚至目前的政府间气候变化专门委员会预测最高47度估计相去甚远。虽然有一些的不确定性这些数字,至少有一个很好的机会,失控的温室过渡点的范围。< / p > < blockquote > < p >为什么全球变暖失控的可能性<强>尽管目前化石燃料存款一旦被大气中> < /强大?< / p > < /引用> < p >的地球有更多的CO 2 <子> < /订阅>大气中数亿、数十亿年前,虽然有一些不确定性多厚的气氛,好大气模型是不可能的,但很可能CO 2 <子> < /订阅>水平高出几个数量级几十亿年前比现在,但这不是太多的问题,因为太阳的热量较小和较明亮。< / p > < p > < a href = " https://i.stack.imgur.com/cCKTj.jpg " rel = " nofollow noreferrer " > < img src = " https://i.stack.imgur.com/cCKTj.jpg " alt = "在这里输入图像描述" > < / > < / p > < p >这个图表给出了一个转变是如何发生的,而且,在地球的过去,地球是事实上,据信< a href = " https://en.wikipedia.org/wiki/Snowball_Earth " rel = " nofollow noreferrer " >是一个雪球< / >长时间,甚至更高的CO 2 <子> < /订阅>。< / p > < p > < a href = " https://i.stack.imgur.com/10B7P.png " rel = " nofollow noreferrer " > < img src = " https://i.stack.imgur.com/10B7P.png " alt = "在这里输入图像描述" > < / > < / p > < p >也看到< a href = " https://en.wikipedia.org/wiki/Faint_young_Sun_paradox " rel = " nofollow noreferrer " >微弱的年轻阳光悖论< / >。< / p > < p >还有其他因素。火山活动将微粒,所以2 <子> < /订阅>高反射阳光的氛围和冷却地球和地球可能是更多的火山几亿,几十亿年前。 Large meteor impacts like the Chicxulub impact create flash warming followed by years of significant cooling caused by dust and ash blasted into the upper atmosphere. There were, certainly, large enough meteors impacts during the late-heavy bombardment that the oceans boiled away and Earth was heated up and the atmosphere was hot and filled with water-vapor as well as CO2, but those were fleeting periods in geological time. The dust and debris blown into the atmosphere leads to fairly rapid cooling following those large impacts.
The sun was too cold in the Earth's past for Earth to ever experience a runaway greenhouse effect, but in a billion years or so, that is expected to change.