"To achieve a 1.5 degrees temperature goal, the world must agree to a fair allocation of carbon space and massive enhancement of financial and technological support from developed countries"

A joint statement made by Prof. T Jayaraman from Tata Institute of Social Sciences, Prof. Anand Patwardhan from University of Maryland and IIT-Mumbai and Chandra Bhushan, Deputy Director General, CSE

  • Professors from TISS, IIT Mumbai/University of Maryland and CSE issue joint statement

  • Statement says growing momentum on restricting global temperature rise to 1.5 degrees may help avert worst impacts of climate change

  • Doing this will require massive financial technological and financial support from developed countries

  • Need to allocate carbon budget and need for massive investments in low carbon technologies

Paris, December 9, 2015: At the Paris climate conference, there is growing momentum for tightening the global goal from 2 degree Celsius to 1.5 degree Celsius – a target that may better help the world avoid the worst effects of climate change. Developed countries have openly given their support to this goal; India and China have also shown their willingness to consider this temperature goal.

While we welcome this increase in ambition, we would like to draw the attention of the climate negotiators to the need to allocate the remaining carbon budget in a fair manner to all countries so that there is a chance for meeting this temperature target.

We would also like to emphasis the fact that meeting this temperature goal would require massive enhancement of financial and technological support from the developed countries to the developing countries so that they are able to move quickly onto low-carbon development pathways. In addition, developed countries will have to significantly increase the level of their own efforts and reach net zero emissions in the next 5-10 years. In the absence of such commitments, a 1.5 OC temperature target would remain a hollow shell – devoid of any real significance.

Practicality of 1.5O C temperature goal

As per the Fifth Assessment report of IPCC (AR5), for a 50 per cent probability of limiting temperature increase to 1.5 degree Celsius, the total carbon dioxide emissions allowed from 2011 till 2100 amount to 550 giga-tonnes (Gt) of CO2. For a 33 per cent probability of keeping temperature increase below 1.5 degree Celsius, the corresponding figure for cumulative emissions is 850 Gt CO2. But if the world wants to raise the certainty of meeting this temperature goal to 66 per cent, then the budget shrinks to a mere 400 Gt CO2.

The UNFCCC’s “Synthesis report on the aggregate effect of the intended nationally determined contributions (INDCs)” estimates that the global carbon dioxide emissions for 2011-2025 will aggregate to 542 Gt CO2 and for 2011-2030 will aggregate to 748 Gt CO2. 

Comparing the existing INDC’s to the available budget indicates that for a better than even chance of meeting the 1.5 degree Celsius target, the remaining carbon budget is exhausted well before 2030 (see Table below).

Table: CO2 emissions corresponding to 1.5 deg C (Giga tonnes of CO2)





Budget (2011-2100)




Consumption till 2025




Consumption till 2030




Balance (Budget – 2030 consumption)

(-) 348

(-) 198


Who will appropriate how much carbon space?

The US and the EU would consume 128 Gt CO2 between 2011 and 2030. If we take available carbon space to be 550 Gt CO2 (for a 50 per cent probability of staying below 1.5 degree Celsius) then the EU and the US alone will consume 23 per cent of the budget. Annex-I countries as a whole would emit 187 Gt CO2 between 2011-2030 – 34 per cent of the total budget.

India most likely will  be emitting only 58 Gt CO2 until 2030 – 10.5 per cent  of the available budget of 550 Gt CO2. Even at higher growth rates of GDP (using the figure quoted by the Indian government in its INDC), this may go up to 87 Gt CO2 -- 16% of the budget of 550 Gt CO2. India’s emissions would, therefore, be less than half of the Annex 1 countries, though India has approximately the same population as all Annex 1 countries combined together. The developed countries under the current dispensation would continue to misappropriate the remaining carbon space even in the future.

Need to allocate carbon budget and need for massive investments in low carbon technologies

Currently there are no limits on how much countries can emit. We need limits so that countries individually and the world collectively remain within the available carbon space.

But the carbon space for a 1.5 degree Celsius target is so limited that developed countries will have to reach net zero emissions in next 5-10 years. Developing countries will have some more time, but their development space will be so constrained that they will need massive support in terms of finance, technologies and capacity so that they are able to meet their basic development and poverty alleviation needs while remaining within the available carbon budget.

We would like to point to the fact that even for 2 degree Celsius, the developed countries INDC’s fall well short of their fair shares; and very significant additional finance and technology support for developing countries is needed. We, therefore, would like to first see an agreement on all elements that credibly deliver on 2 degree Celsius in a fair and equitable manner. After that, negotiators need to chalk out a plan about what more needs to be done to raise the ambition to 1.5 degree Celsius. In the absence of real commitments, even 2 degree Celsius target has no real significance. 

CSE has a five-member team attending the CoP21 deliberations in Paris. Please contact us if you need to speak with any of them.


The CSE Delhi team: Souparno Banerjee, souparno@cseindia.org, 99108 64339

CSE Paris team: Chandra Bhushan, chandra@cseindia.org;