Coming up in December of 2015, the UN will host the 21st Conference of Parties in Paris.

2015年12月聯合國將於巴黎召開締約方第21次會議(COP21)

The focus of this year’s COP21 will be climate change. Most of the leading nations in the

今年,COP21聚焦於氣候變遷,多數領導國家

world have been asked to pledge to keep the rise in global temperature under 2 degrees celsius.

必須答應共同把暖化溫度控制在2℃以下

It’s clear that a sharp curb in co2 and greenhouse gas emissions is needed.

很顯然我們必須大量減排CO2等溫室氣體

Unfortunately, not all countries agree on how best to go about that.

遺憾的是，各個國家在作法上難以達成共識

There’s two main plans: one says everyone gets a per capita cut. Everyone, all nations,

有兩派說法:一派堅持減少人均排碳,地球上每個人

have an equal responsibility to curb emissions. The other says that countries who polluted

都有減排責任；另一派則表示已開發國家

more in the past have more responsibility to curb their emissions, so that those that

過去排放大量污染,減排責任較大

polluted less can have some wiggle room to still grow.

而目前污染較少的國家應有適度發展空間

But one study from the Center for International Climate and Environmental Research – Oslo (CICERO)

不過,奧斯陸國際氣候與環境研究中心(CICERO)

found that the US, EU, and Chinese emission pledges leave very little room for

指出：美國、歐盟、及中國的承諾

other countries to emit in a 2°C world. Those countries say their pledges are “fair and

其他國家幾乎沒有排放的餘地。這些國家認為此承諾「公平

ambitious” but might not be enough to keep things cool enough.

雄心壯志」,但顯然仍不足以冷卻地球

The 2 degrees target was decided back in 2009 at another UN conference in Copenhagen, where

2℃的目標訂於2009年的哥本哈根聯合國峰會

in the Copenhagen Accord countries recognized “the scientific view that the increase in

當時締約方一致認同「科學觀點指出

global temperature should be below 2 degrees Celsius". But why did they choose that number?

全球溫度上升不應超過2℃」。但為何選這個數字呢?

Well that number can be traced back to two papers published in the mid-70s by Professor

這就要追溯回70年代的兩篇論文

of Economics William Nordhaus at Yale University. In these papers he said that “If there were

發表人是耶魯大學經濟系的Nordhaus教授,他說:「若是

global temperatures more than 2 or 3° above the current average temperature, this would

全球溫度從現在開始上升超過2或3℃

take the climate outside of the range of observations which have been made over the last several

那麼未來氣候的劇變將遠遠超過

hundred thousand years”.

幾十萬年來的觀察」

Ice core sampling in the mid 80s confirmed that two degrees above pre-industrial levels

80年代中期的冰芯取樣證實,自工業革命後上升2℃

hadn’t been seen on the planet in at least the last 100,000 years. Another report in

的確是十萬年來不曾出現的

the early 90s reconfirmed that the consensus that two degrees is “an upper limit beyond

另一項90年代的報告再次證實:2℃是「臨界點

which the risks of grave damage to ecosystems... are expected to increase rapidly”.

很快就會達到…屆時生態系統將面臨空前危機」

Since then, that number has had huge visibility as a “speed limit” of sorts. As we might

自此,人們就把這個數字看得和「速限」一樣重要,一旦

pass that number, the worse effects on the climate and the faster those effects will

超過,將發生史上最糟的效應,而且會加速

happen.

發生

Effects like global sea level rise. A study published in the journal Nature Climate Change

海平面上升是一例,《自然氣候變遷》有一則研究指出

found that levels could rise 1.5 and 4 meters by the year 2300 if the Earth warms at least 2 degrees.

到了2300年,地球若暖化2℃以上,海平面將可能上升1.5～4公尺

The effects of which we’ve talked about in previous episodes. Links for those

前幾集我們介紹過一些災難效應,若有興趣

down below.

請看下面

Not only could oceans rise, but rivers could run dry, according to a study published in

研究指出,不止海平面上升,河床也將乾涸

the journal Philosophical Transactions of the Royal Society A. In analyzing water scarcity,

這項研究來自《自然科學會報A》,分析水資源短缺

researchers found that water supplies would dwindle thanks to more pressure from a growing population.

科學家指出,水資源減少,歸因於全球人口有增無減

If the temperatures climb even higher, to four degrees, some river beds will

若溫度攀升至4℃,有些河床會乾凅

be drier but some might be wetter, which could put more pressure on stressed out governments.

而有些地方則會有水災; 這會讓早已焦頭爛額的政府忙上加忙

As the temperatures get worse, the effects will be more extreme.

溫度越高,災難效應越極端

In another study also published in the same journal, researchers found other effects include

《自然科學會報A》有另一項研究列出其他效應:

no sea ice in the arctic in the summer, coral reef die outs, melting of permafrost which

北極浮冰到了夏季將全部融化、珊瑚礁死光、永凍土融化

will release more greenhouse gases into the atmosphere, and “die-back of the Amazon

釋出大量溫室氣體、亞馬遜雨林將消失

forest”. The study also predicts that semi-arid and arid places, like sub-Saharan Africa will

研究預測漠南非洲等乾燥或半乾燥氣候帶

be even drier, they predict the collapse of the agricultural system in that region.

將嚴重乾旱,可能造成當地農業生產系統崩解

So it’s safe to say that if the world warms up, as it looks like it very well might, Earth

所以絕對可以這麼說:地球非常有可能暖化,一旦暖化

is going to look a lot different.

地球樣貌就會完全改觀

We’re witnessing one of the effects of a climate change right now! Arctic ice levels

我們已經見識了其中一項氣候效應:北極浮冰數量

have been the lowest scientists have ever seen. So what happens if all the ice melts?

創新低,前所未見。若是冰全融了該怎麼辦?

What changes have you noticed, perhaps longer summers?

你還注意到哪些效應嗎?例如夏季變長?

Tell us about it down in the comments below

請在底下留言

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