RSS
热门关键字:  诗歌I  www mad com  本期词汇  bjq  thanksgiving
当前位置 :| 主页>新闻>

Climate change: 'Hothouse Earth' risks even if CO2 emissions slashed

来源:BBC 作者: 时间:2018-08-07 Tag: 点击:

It may sound like the title of a low budget sci-fi movie, but for planetary scientists, "Hothouse Earth" is a deadly serious concept.

Researchers believe we could soon cross a threshold leading to boiling hot temperatures and towering seas in the centuries to come.

Even if countries succeed in meeting their CO2 targets, we could still lurch on to this "irreversible pathway".

Their study shows it could happen if global temperatures rise by 2C.

An international team of climate researchers, writing in the journal, Proceedings of the National Academy of Sciences, says the warming expected in the next few decades could turn some of the Earth's natural forces - that currently protect us - into our enemies.

Each year the Earth's forests, oceans and land soak up about 4.5 billion tonnes of carbon that would otherwise end up in our atmosphere adding to temperatures.

But as the world experiences warming, these carbon sinks could become sources of carbon and make the problems of climate change significantly worse.

So whether it is the permafrost in northern latitudes that now holds millions of tonnes of warming gases, or the Amazon rainforest, the fear is that the closer we get to 2 degrees of warming above pre-industrial levels, the greater the chances that these natural allies will spew out more carbon than they currently now take in.

Back in 2015, governments of the world committed themselves to keeping temperature rises well below 2 degrees, and to strive to keep them under 1.5. According to the authors, the current plans to cut carbon may not be enough if their analysis is correct.

"What we are saying is that when we reach 2 degrees of warming, we may be at a point where we hand over the control mechanism to Planet Earth herself," co-author Prof Johan Rockström, from the Stockholm Resilience Centre, told BBC News.

"We are the ones in control right now, but once we go past 2 degrees, we see that the Earth system tips over from being a friend to a foe. We totally hand over our fate to an Earth system that starts rolling out of equilibrium."


最新评论共有 0 位网友发表了评论
发表评论
评论内容:不能超过250字,需审核,请自觉遵守互联网相关政策法规。
用户名: 密码:
匿名?
注册