Country pledges overshoot Paris temperature limit

June 29, 2016
Global greenhouse gas emissions as implied by INDCs compared to no-policy baseline, current-policy and 2 °C scenarios. (Figure 1 from paper) Credit: Rogelj et al 2016

Pledges made for the Paris agreement on climate change last winter would lead to global temperature rise of 2.6 to 3.1°C by the end of the century, according to a new analysis published in the journal Nature. In fact, the entire carbon budget for limiting warming to below 2°C might have been emitted by 2030, according to the study.

"The Paris Agreement was a historical achievement for the world's response to , aiming at limiting warming to below 1.5°C and 2°C. It puts in place a flexible framework for a long-term transformation towards a low-carbon society. But our analysis shows that these measures need to be strengthened in order to have a good chance of keeping warming to well below 2°C, let alone 1.5°C," says Joeri Rogelj, a researcher at the International Institute for Applied Systems Analysis (IIASA) who led the study.

The 2°C target aimed to limit future climate change to an average temperature increase of below 2°C above preindustrial levels, as research suggested that this could help avoid some of the most dangerous impacts of climate change. The target was agreed upon by 190 countries at the Cancun climate meeting in 2010. In Paris last December, countries strengthened this target by requiring temperatures to be limited to "well below" 2°C and furthermore agreed that they should strive to limit temperature rise even further, to 1.5°C. Some studies suggest that even two degrees of warming would lead to unacceptable impacts, particularly in vulnerable countries such as island nations and least-developed countries.

The new study provides an in-depth analysis of the pledges which countries submitted at the Paris climate meeting in December, the Intended Nationally Determined Contributions (INDCs). In order to assess what would happen after the pledge period ends in 2030, the researchers assumed that emission reduction efforts would be continued at the same level of effort after 2030. Based on these projections, and using a variety of different models, they estimated that median global temperatures would reach 2.6 to 3.1°C by 2100. The researchers also examined what additional measures would be necessary after 2030 to limit future to 2°C or 1.5°C in 2100.

Niklas Höhne, a researcher at the NewClimate Institute in Germany and Wageningen University who also worked on the study, says, "To go the rest of the way, we would need to assume much more stringent action after 2030, which leads to emissions reductions of about 3-4% per year globally. But in practice, switching to such stringent reductions right after 2030 would be challenging, and require time—that means that in order to ensure a chance of meeting these targets, we need significant further action from countries before 2030."

The study also provides a careful analysis of the uncertainties surrounding future emissions and temperature targets. For one thing, the emissions reductions from the INDCs remain uncertain, since the INDC's themselves are not consistently framed, and some of the pledges include conditional statements, for example, that a country will only implement ambitious emissions reductions if it receives funding from others. Comparing the possible emission levels that the INDC's could imply, the researchers found a range of uncertainties of 6 billion tons of CO2 equivalent, or roughly the entire emissions of the United States in the year 2012.

The other major uncertainty lies in how much temperatures will rise in response to various emission levels. For this reason, temperature targets are often interpreted in terms of probabilities, with the aim to have a 66% likelihood of keeping temperature to below 2°C above pre-industrial levels. The study also found that the same INDCs would only avoid 2.9-3.4°C of warming with a 66% chance and 3.5-4.2°C of warming with 90% chance until 2100.

Harald Winkler, a researcher at the Energy Research Centre in South Africa, also worked on the article. He says, "While some uncertainties, like the temperature response uncertainty, are virtually irreducible over the coming years, uncertainties about what the INDCs add up to in terms of emissions are not. Immediate future work should therefore focus on a better understanding of what the INDCs mean and how they link to other socio-economic objectives, including the UN Sustainable Development Goals." IIASA Energy Program Director Keywan Riahi says, "Our study clearly shows that the current national (INDC) plans are too incremental and thus inconsistent with the long-term ambition from the Paris agreement. If we want to keep 2°C within reach, we'll need much more rapid and fundamental changes. The hope is that the post-Paris policy process can deliver this."

Explore further: Current climate commitments would increase global temperature around 3 C

More information: Nature, nature.com/articles/doi:10.1038/nature18307

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18 comments

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Shootist
1 / 5 (9) Jun 29, 2016
Vote for Trump. End this foolishness..
antigoracle
1 / 5 (9) Jun 29, 2016
Every week we see another reason reaffirming the fraud that every climate model is, yet the AGW Cult continues with their doom and gloom lies.
HeloMenelo
4.6 / 5 (10) Jun 30, 2016
Everyday we see another reaffirming post by monkey antisciencegorillacle promoting monkeybusiness and tree swinging. as for the science i see a lot on this site backed with countless of evidence, other than the monkey chatter by you and your socks that is ;)
gkam
2.3 / 5 (9) Jun 30, 2016
What will the Deniers say when it is too late? They will STILL deny it is happening, unable to admit error, . . again. Most of them also fell for the phony screams of "WMD!".

Political prejudice and poor character make for conservative choices.
SteveS
4.6 / 5 (10) Jun 30, 2016
Vote for Trump. End this foolishness..


"I'm 100 per cent Democrat myself, and I like Obama."
Freeman Dyson

http://www.thereg...terview/

StudentofSpiritualTeaching
3.4 / 5 (5) Jul 01, 2016
As long as the underlying overpopulation problem is not tackled, we can continue to fight windmills and the symptoms for fortunes of money. What more will it take to wake up the sleeping brains?
KBK
5 / 5 (3) Jul 03, 2016
Recent scientific studies (only a few so far) seem to be saying that it is carbon content in the atmosphere that MIGHT hold back the expected ice age. Ice ages are the current norm, with an approximate 10k year inter-glacial warm period.

A warm period that we are apparently at the end of.

At the same time sunspot activity is, relatively speaking... going dead. This might be the onset of the bulk of a fight between carbon rise vs that of a coming glacial. The weather sure is screwy.

If it turns out that a carbon dioxide level at about 50-100% higher than we have now, can hold off a coming 100k year long glacial period, then we might want to look at that.

Problem being, if true, it's one hell of a massive vehicle to be trying to drive around the block, with slow and near unpredictable behaviors.

To possibly have and allow carbon dioxide increase , which has increased plant growth (NASA STUDY), but to get rid of the pollution and garbage angle. Ie, cold fusion, etc.
KBK
5 / 5 (7) Jul 03, 2016
The second problem aspect..... is the methane bomb problem.

So perfect, it is......that it is almost as if someone planted it there as a civilization trip wire bomb.

Talk about walking a fine line... a high wire act of immense proportions.

So, to have high enough carbon to prevent an ice age onset, but not enough to trigger the methane release.

As the methane release is probably worse (understatement) for humanity than any ice age could be.

We are touching the edges of the methane bubble/burp release, right now. Getting the pollution out of the atmosphere can slow that, though. It's the blackening of the snow caps that is partly to blame.

Tough problem, one that seems to be saying 'get your civilization in order, if you want it to survive'.

A fine line high wire act with trip wire bombs on all sides.
Steve 200mph Cruiz
5 / 5 (12) Jul 03, 2016
Shootist,
Trump will never have any control over the UN or science.

If you want to stop hearing about this, going to have to vote for someone to fix it.

Remember the ozone layer scare? We all pitched in, pretty much did what we could to stop its deterioration, and now we don't hear about it anymore.
antialias_physorg
4.5 / 5 (8) Jul 04, 2016
Shootist:

Vote for Trump.

Why am I not surprised?
antiantigoracle
Jul 04, 2016
This comment has been removed by a moderator.
HeloMenelo
4.2 / 5 (5) Jul 04, 2016
Nope the reality has all the facts against You and your socks for over 10 years now, Therapists are needed for those overwhelmed by scientific evidence, they are to scared to admit the truth, and you know what that means little monkey... ;)

Denier's read like an open public book, and i must say it's a very dull existance, luckily we can make it fun for you by throwing you bananas and see you swing those branches everytime we throw them... that's fun... ;) here have another....:D
HeloMenelo
4.2 / 5 (5) Jul 04, 2016
....c'mon bonobo one more cracker of a luagh and i'll throw ya 2... deal ? ;)
HeloMenelo
4.2 / 5 (5) Jul 04, 2016
laugh that is, so lets have it :)
gkam
1 / 5 (5) Jul 04, 2016
I am the hat of antiantigoricle.
ElectricBoobVerses
Jul 04, 2016
This comment has been removed by a moderator.
BigusDickus
Jul 06, 2016
This comment has been removed by a moderator.
leetennant
5 / 5 (3) Jul 06, 2016
Anything over 2 is pretty well catastrophic. We are completely fucked. It's enough to make you give up on humanity.

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