(The version appearing in print in the Times of India of 22nd Oct., 2018 is an edited down version of this full text from the interview by Sugandha Indulkar of TOI).
What, for you, were the most significant changes between the latest IPCC report on limiting global warming to 1.5 degrees centigrade, and the earlier reports?
The IPCC Special Report on Global Warming at 1.5 degrees, to give it its official title, is particularly noteworthy because it was in response to a specific request from the Parties to the Paris agreement. For the first time in the Paris agreement the limit of 1.5 degrees centigrade of global warming above pre-industrial levels was mentioned as a goal that countries should strive to achieve. Hence a special report from the IPCC was called for. Subsequently, in designing the outline of the report, it was agreed that it would look at the methods of achieving these goals; involving, mitigation options and consequences of adaptation even to 1.5 degrees of warming. It would also examine the differences between mitigation and adaptation for a 1.5 deg and 2 deg target for limiting global temperature rise, while keeping up the goal of sustainable development. So in this respect, the report was significantly different.
With respect to specific details, the report makes it very clear that the difficulty of reaching the 2 deg target was less steep compared to achieving the 1.5 deg target. At the current rate of emissions, of about 42 billion tonnes of carbon dioxide per year, the cumulative emissions permitted for the 1.5 deg target would be reached very quickly — between 10 to 30 years from now on. For the first time, the report introduces a widespread role for negative emissions arising especially through methods of removal of carbon dioxide from the atmosphere. Some of these methods have been field tested on a limited scale, but by and large the scale on which they are required for a 1.5 deg limit are significantly very difficult, some would say impossible, to achieve.
Were there difficulties in understanding the role of the carbon budget for the target of 1.5 degrees centigrade warming?
The report pays attention to some of the features that are important in understanding the achievability of the 1.5 goal. One is the notion of the total carbon budget. This is the limit on the cumulative emissions of greenhouse gases, from pre-industrial levels in order to stay below the defined temperature limit of global warming. Due to various scientific uncertainties, quantifying this limit depends on the probability of reaching this goal, the greater the probability the smaller the limit on cumulative emissions. The developing countries were concerned with ensuring that adequate importance is given to the role of past emissions as well as the future emissions, in their contribution to global warming. Getting this correct was one of the major agendas at the 48th session of the IPCC at Incheon where the report was finalised. In the final formulation it is made clear that the total carbon budget is an important concept, and that of this total budget 2200 billion tonnes have already been emitted. So between 420 to 770 billion tonnes of carbon di oxide, is all that we can emit in the future.
This range fits very clearly within the time frame of 10 to less than 30 years, that I mentioned earlier. There are other uncertainties about including non CO2 gases which contribute to global warming. But all effects taken into account, the message is that the world has very little carbon space left if we are talking about 1.5 — in the case of 2 deg warming it is somewhat larger.
The mitigation measures call for big adjustments to supply and demand of energy. Isn’t this going to be hard for governments in developing countries?
The short answer to this question is an unqualified ‘Yes’. The investment required in mitigation for a 1.5 degree target is very high. By 2050, the global average annual investment in low carbon and energy efficient technologies needs to be up scaled by roughly a factor of five compared to the present day. In another calculation the investment in the energy system involved between 2018 to 2035, to achieve the 1.5 deg target, amounts to about 2.5 percent of the world’s GDP
So the numbers we are talking about are quite significant and they will be undoubtedly a burden on developing countries, even if the developed countries do their rightful share, which they are not doing at the moment.
Ones needs to bear in mind that these estimates are based on models, not real world scenarios. The gap between modelling and the real world can be wide. The report however makes it clear that the industrial, economic and social transformation required is unprecedented. The IPCC report has also not factored in the effect of the US withdrawal from the Paris Agreement (and the dampening effect it has on the policies of other countries) on the feasibility of the 1.5 deg goal.
Coming to sources of fuels, would a shift from fossil fuel to biofuel help reduce emissions of greenhouse gases in India?
Surely a shift from fossil fuel to biofuel will help reduce emissions, in addition to the large-scale deployment of other renewable energy technologies as well. In this context, the increased reluctance of developed nations to share their technology to cut emission with developing countries stands in the way of achieving this global target. There are clearly many important experiments being conducted all over the world in new low-carbon or carbon-free technologies, using hydrogen fuel cells in transportation, for instance. There is a clearly a technological movement which is taking place. All these are positive pointers. What however, is worrisome, is the scale at which these experimental techniques can be implemented in the real world, the costs involved and how the costs will be borne.
In the current scenario what are the top three ways by which India can do better than its Nationally Determined Contributions?
In India, doing better than the Nationally Determined Contributions is going to be difficult — already our renewable energy target is very ambitious. We have to put all our resources in fulfilling our energy commitments. Afforestation and such measures are effective to some extent. It needs to be supplemented with other measures. In speaking of the prospects of India doing significantly better than its current commitments we have to articulate clearly the already onerous task that lies ahead of us in this area.
Have extreme weather patterns started showing up in Indian data?
We have unambiguous evidence of rising temperatures and the increased occurrence of heatwaves, throughout the world. India is no exception. With regard to precipitation, the issue is more ambiguous. For India, we know with a high degree of confidence that total rainfall will increase, more so with 2 degree warming as compared to 1.5 degrees. The impact of climate change currently on the monsoons is not easy to determine, though extreme rainfall events are indeed showing a rising tendency. We have to watch with caution the various trends, which need detailed analysis. It is an evolving scenario. Easy conclusions should be avoided and both policy makers and the lay public should be more aware of the nuances associated with such analysis.
Overall, globally the impact of 1.5 deg warming on extreme weather will be significant but lower in many respects compared to 2 deg warming.
What does the IPCC report mean when it talks about limited capacity to adapt to risk of climate change?
There are several dimensions to this question. Adaptation is not an indefinite process. There are limitations in the capacity to adapt to certain impacts once we cross a particular threshold. We are also dealing with countries with different levels of development. For instance, in the Netherlands, for sometime now, they are experimenting with houses which float during floods, rising and falling with the water levels. In the Indian context however, such large-scale housing in highly flood-prone regions is far from being a reality. In a variety of contexts across the world, depending on both the geo-physical and socio-economic circumstances, the capacity to adapt varies, it is not uniform. We must also distinguish clearly between international and national policy. India has to work out its stand in this matter. The enthusiasm shown by scientists of developed countries to achieve the 1.5 degree centigrade target has to be matched in practice by deep-rooted policy transformations in their countries. The USA should be brought back into the picture and should actively participate, though how this can be achieved is difficult to say.
Speaking of the developed vs developing country gap, how well has the report captured the equity dimension in the pursuit of the 1.5 deg target?
Unfortunately, the equity dimension, tends to be significantly underplayed by developed countries, including in their research in terms of climate change, mitigation and adaptation. The report has some general recognition of equity in vulnerability and adaptation and some extent in costs of mitigation. But beyond that they have very little awareness of its and equity seems to be quite underplayed in this report. The multi-dimensional approach required to meet the 1.5 degree centigrade global target has to be based on equity – but how that is to happen, the report does not offer much. One can only hope that the Sixth Assessment Report due in three years will examine this in more detail and research in this aspect must be significantly enhanced, especially from countries like India.