The window is closing for the two-degrees target

Av: Jill Johannessen

Monday November 11 climate negotiators and key politicians from all over the world are gathering in Warsaw on the 19th climate summit (COP19). In the next two weeks they will continue the negotiations for a global climate deal, which, if on track should culminate in a new global treaty in 2015. Bjerknes scientists are involved in a project that is presented in one of the many side-events that run parallel to the negotiations.

Since the last climate summit in Doha last year, the Intergovernmental Panel on Climate Change (IPCC) launched the first sub-report of the Fifth Assessment Report, which gives the status on climate change research. The report concludes that it is extremely likely that climate change occurring since 1950 is mainly a result of human activity, in particular, CO2-emissions from fossil fuel production and consumption. Hence, the carbon budget has become an important factor. It tells us how much CO2 can be emitted globally before we reach the two-degree-target and how much of known fossil reserves must accordingly be left in the ground. IEA has concluded that two-thirds of today’s proven reserves of fossil fuels cannot be extracted before 2050 in order to limit warming to less than two-degrees since pre-industrial time. Numbers in the IPCC report indicate that even less can be used.

Carbon trouble

According to IPCC’s newly released report on the Physical Science Basis we can emit about 800 GtC (billion tons) before we surpass the two-degree target. Figure 1 below shows that we have already emitted more than half of this amount (see black dots). This means that we have most likely about 300 GtC left to emit within to the two-degree scenario (see purple dots). In practice, this means that we have to limit the extraction of fossil fuel reserves that are not yet developed in order to keep the emissions under the total of 800 GtC.

Figure 1. Cumulative anthropogenic CO2-emissions from 1870 (GtCO2)

 

Figure SPM.10: Global mean surface temperature increase as a function of cumulative total global CO2 emissions from various lines of evidence. Multi-model results from a hierarchy of climate-carbon cycle models for each RCP until 2100 are shown with coloured lines and decadal means (dots). Some decadal means are indicated for clarity (e.g., 2050 indicating the decade 2041−2050). Model results over the historical period (1860–2010) are indicated in black. The coloured plume illustrates the multi-model spread over the four RCP scenarios and fades with the decreasing number of available models in RCP8.5. The multi-model mean and range simulated by CMIP5 models, forced by a CO2 increase of 1% per year (1% per year CO2 simulations), is given by the thin black line and grey area. For a specific amount of cumulative CO2 emissions, the 1% per year CO2 simulations exhibit lower warming than those driven by RCPs, which include additional non-CO2 drivers. All values are given relative to the 1861−1880 base period.

- If we continue with todays emissions, we have only 30-50 years left before we have emitted the CO2 amount that will drive us past the two-degree-target, says Eystein Jansen, the Bjerknes Centre Director and Lead Author in the IPCC’s latest report. In this scenario we need to have zero-emissions globally in the second half of the century in order to stabilize CO2-concentration in the atmosphere, Jansen explains.

What is the strongest political message in the IPCC report that the climate negotiators should bring with them to Warsaw?

 - The main message is that it is urgent to get control over the emissions. The emission peak must be reached and emissions should start to decline during the next ten years. This is the only alternative if we are to limit the warming to two degrees, which in itself leads to substantial climate change. The second message is that much of the climate change we initiate is impossible to reverse. Our emissions will have consequences for several hundred of years. These circumstances put a lot of pressure on our generations to act responsibly for future generations. We have a choice, and the IPCC report underlines the risk in continuing business as usual, says Jansen.

 

 

 

 

Important with progress

The Warsaw summit will probably only be an intermittent event towards the 2015 summit in Paris. According to the Durban Platform two years ago, a global treaty shall be ready in Paris, and take effect from 2020.

- Warsaw will not be a decisive meeting, but it is important with progress on several issues in order to reach a binding agreement in Paris.  For example, it is important that the Green Climate Fund makes headway, which shall finance climate transformation and adaptation in developing countries. There are also parallel processes in the negotiations that not necessarily demand a global treaty with formal national emission reduction commitments, e.g. linked to specific sectors and other drivers of climate change. Such advances and agreements can help to create trust that is needed to reach a binding global climate treaty in 2015, says Jansen.

 

 

 

 

 

 

The Bjerknes Centre takes part in side-event

Besides key politicians and negotiators the international climate summits attract thousands of researchers, environmental activists, business actors, and others who want to share their knowledge and views, and try to make an impact on the negotiations. Bjerknes scientists are involved in a COP 19 side-event Monday November 11, called the "Durban Action Global Scenarios for 2C: feasibility, implications and impacts". The organizer behind this event is the EU project IMPACT2C, where the Bjerknes Centre/Uni Research is one of the partner institutions. Bjerknes researchers contribute significantly to this project by projecting and quantifying impacts under 2°C warming in Europe and vulnerable regions of the worlds.

- It means a lot to us to be able to present our project on this arena. The hope is that the results that will be produced in our project will find their way into policy discussions at both national and supra-national levels, such as the COP. The results will help to guide responses so that actions are developed in an efficient and equitable fashion, says researcher Stefan Sobolowsk at the Bjerknes Centre and Uni Research. He will not be present in Warsaw.