Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

If a major economy takes the lead, warming could be limited to 2°C

27.10.2015

Though most countries around the globe agree that warming must be limited to 2 degrees Celsius to avoid the raft of climate risks, they clash about who should do what to reach this target. Hence the issue of allocating greenhouse-gas emissions reductions will be key for the outcome of the world climate summit COP21 in Paris.

Scientists now found what amount of emissions reductions it takes for a major economy to lead out of the climate gridlock. They conclude that effectively limiting climate change is possible if a major economy acts as a forerunner, while other nations follow – and, importantly, by doing so they do not have to agree on common criteria for fairness.


An interactive website with results for all G20 countries is available at www.mitigation-contributions.org

“If either the European Union or the US would pioneer and set a benchmark for climate action by others, the negotiation logjam about fair burden sharing could be broken,“ lead author Malte Meinshausen from the Potsdam Institute for Climate Impact Research and the University of Melbourne says.

“Our analysis shows that they would have to roughly double their current domestic 2030 emissions reductions targets – which would certainly require substantial efforts. Yet it seems to be one of the few options to stay on track for eventually limiting warming below 2°C and fend off a drastic increase of weather extremes and sea-level rise.“

Two conflicting fairness criteria must be dealt with

While the UN Climate Change Convention holds up the formula of ‘common but differentiated responsibility’, the world is currently divided - simply speaking - into two main camps. One is in favor of distributive justice at some point in the future: emissions per person would be roughly the same in every country by 2050. This includes the EU and the US.

The other camp, with China and India, calls for corrective justice: the emissions of the past should be taken into account to achieve equal cumulative emissions per person. This kind of fairness scheme would mean that those that emitted less in the past can emit more in the future on a per-capita basis.

Analyses of emissions reduction pledges and past negotiations show that, unsurprisingly, countries tend to adhere to the allocation principle which allows them to least reduce emissions, compared to their international competitors. Since China and India industrialized only recently, in the past they emitted less than the EU and the US did. Yet today China emits more than the EU and US combined on an absolute basis, and about the same as the EU on a per-capita basis.

“This seems less utopian than a uniform regulation”

“Now we have calculated how much a major economy would have to cut its greenhouse gas output if all the other countries would follow the emissions allocation scheme that is most favourable to them – so some base their reduction number on the equal per capita scheme, others include the historical emissions, and still the 2-degree limit is met,” says co-author Louise Jeffery from the Potsdam Institute. The scientists call this concept diversity-aware leadership.

“This seems less utopian than a uniform regulation,” says Jeffery. “But it builds on the assumption that most economically relevant countries participate in one way or another and ensures that the global efforts are successful in limiting warming to 2 degrees.”

In this scenario, the US national emissions reduction target would have to be roughly 50 percent instead of currently 22-24 percent below 2010 levels by 2030. Alternatively, the equivalent target for the EU would have to be about minus 60 percent instead of currently 27 percent below 2010 (27% below 2010 being equal to the announced 40% below 1990 target).

It’s in the numbers: China will not take the lead

China could also take the lead, but beyond political considerations already the numbers show that this is unlikely. In fact, the quantification of the Chinese pledge indicates the largest gap between a leadership target and a currently proposed peaking by 2030. If China wanted to assume leadership, China would have to reduce emissions by 32 percent below 2010 levels by 2030. In a scenario of equalized cumulative per-capita emissions, it would only need to reduce them by 4 percent. This seems little, but would in fact be a most crucial contribution.

“If you look at what pledges the countries put on the table for Paris so far, it’s clearly not enough to keep warming within the internationally agreed 2-degree limit – hence the current ‘intended nationally determined contributions’ can only be regarded as a first step in the right direction,” says co-author Sebastian Oberthuer from Vrije Universiteit Brussel. Based on IPCC databases, the scientists derived their proposition which is contrary to previous assumptions about allocation schemes. “If we postpone action until we have universal agreement on a fair allocation of emissions reductions,” he says, “the result will be fair only in that everybody will lose – because climate change will hit us all.”

"Our study thus anticipates the upcoming Paris climate summit, which will see countries make their mitigation contributions in an independent bottom-up manner,” says Joeri Rogelj from the International Institute for Applied Systems Analysis. “This is a fundamental break with the past,” he says, “and in this new landscape, our study introduces an important new concept which helps us understand how major countries can still assume a leadership role on this highly fragmented playing field."

An interactive website with results for all G20 countries is available at www.mitigation-contributions.org

Article: Meinshausen, M., Jeffery, L., Guetschow, J., du Pont, Y.R., Roegelj, J., Schaeffer, M., Höhne, N., den Elzen, M., Oberthür, S., Meinshausen, N. (2015): National post-2020 greenhouse gas targets and diversity-aware leadership. Nature Climate Change Advanced Online Publication [DOI: 10.1038/NCLIMATE2826]

Weblink to the article once it is published: http://dx.doi.org/10.1038/NCLIMATE2826

For further information please contact:
PIK press office
Phone: +49 331 288 25 07
E-Mail: press@pik-potsdam.de
Twitter: @PIK_Climate

Weitere Informationen:

http://www.mitigation-contributions.org

Mareike Schodder | Potsdam-Institut für Klimafolgenforschung
Further information:
http://www.pik-potsdam.de

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: It’s All in the Mix: Jülich Researchers are Developing Fast-Charging Solid-State Batteries

There are currently great hopes for solid-state batteries. They contain no liquid parts that could leak or catch fire. For this reason, they do not require cooling and are considered to be much safer, more reliable, and longer lasting than traditional lithium-ion batteries. Jülich scientists have now introduced a new concept that allows currents up to ten times greater during charging and discharging than previously described in the literature. The improvement was achieved by a “clever” choice of materials with a focus on consistently good compatibility. All components were made from phosphate compounds, which are well matched both chemically and mechanically.

The low current is considered one of the biggest hurdles in the development of solid-state batteries. It is the reason why the batteries take a relatively long...

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Quantum bugs, meet your new swatter

20.08.2018 | Information Technology

A novel synthetic antibody enables conditional “protein knockdown” in vertebrates

20.08.2018 | Life Sciences

Metamolds: Molding a mold

20.08.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>