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

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

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

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

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

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

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

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

polluted less can have some wiggle room to still grow.

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

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

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

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

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

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

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

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

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

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

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

hundred thousand years”.

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

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

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

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

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

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

happen.

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

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

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

down below.

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

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

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

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

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

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

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

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

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

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

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

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

is going to look a lot different.

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

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

What changes have you noticed, perhaps longer summers?

Tell us about it down in the comments below

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