The IPCC report: A clear call for immediate action

The IPCC report is an important wake-up call to the world to not get taken in by the claim that net-zero declarations of developed countries represent ‘ambition’ in climate action. The real question for countries is how much they plan to emit cumulatively from now until they reach net zero and whether this is in keeping with their fair share of the carbon budget.

Tejal Kanitkar and T Jayaraman

---

THE recently released report of the Intergovernmental Panel on Climate Change (IPCC), titled Climate Change 2021: The Physical Science Basis, is undoubtedly an important advance in the assessment of the current state of the climate system, of how the world’s climate got to the state it is in today, how the climate is likely to respond to greenhouse gas (GHG) emissions in the near- and long-term future, and what it would take to keep the world within the limits of safety.

The report underlines that the impacts of climate change are unequivocally of human origin. The world has already warmed by about 1.07 degrees Celsius as compared with pre-industrial times. To restrict the temperature increase to below 1.5°C or 2°C, which are the targets of the Paris Agreement, the world has very little carbon space left.

The report uses ‘multiple lines of evidence’ to assess more accurately than in previous reports, the effects of all GHGs from pre-industrial times to the present. The potential range of future impacts are assessed for illustrative emissions scenarios ranging from scenarios with assumptions of rapid and sustained emissions reductions to scenarios under which very little or indeed no emissions reduction takes place over this century.

Observed warming, its sources and implications

The report categorically states that the observed increases in the atmospheric concentration of ‘well-mixed’ GHGs [i.e., carbon dioxide (CO2), methane and nitrous oxide] since 1750 have been caused by human activities. This increase in GHG concentrations has warmed the atmosphere, ocean and land, and widespread and rapid changes in the climate system have been observed.

Due to the increase in warming, extreme events (e.g., heatwaves, heavy precipitation, droughts, tropical cyclones) have become more frequent and intense. An important advance in the IPCC report is that it is now possible to attribute climate extremes to human influence much more confidently than in earlier assessment reports.

That CO2 is the main determinant of global warming and has so far played a dominant role in increasing global temperatures, is now resoundingly clear. This was a fact that was evident for many years, despite repeated attempts to divert attention from CO2 mainly arising from industrial processes and fossil fuel energy use, so far concentrated in developed countries, with of course the notable exception of China. While other GHGs do play a role, meaningful and adequate climate action requires strategies targeted at reducing CO2 emissions.

Mitigating air pollution and carbon emissions reduction

This perspective on the role of different sources of warming comes from the report’s assessment of new evidence on the overall effect of a range of different climate forcers from the pre-industrial period (1850-1900) till the most recent decade (2010-19). Warming driven predominantly by CO2 emissions, together with methane and nitrous oxide, is actually partially masked by aerosol cooling, the latter mainly from sulphur dioxide and organic carbon. From pre-industrial times till the most recent decade, aerosol cooling has been almost equivalent to warming from methane and nitrous oxides, all of which are ‘short-lived climate forcers’ (so called due to their short-lived presence in the atmosphere, unlike with CO2).

Significantly, the study of the relative significance of aerosols indicates that while climate change and air pollution may have common elements, separate strategies and interventions are required to tackle them. It has been argued of late that getting rid of coal at the earliest would be an effective way to address both air pollution and climate change. The IPCC report makes clear that this is an incorrect assumption if the aim is the rapid reduction of air pollution, which is an immediate health hazard. The report notes that strategies targeted primarily at carbon dioxide reduction would not automatically achieve the air quality levels recommended by the World Health Organization in many heavily polluted regions of the world, even in scenarios where CO2 emissions decline very rapidly. Apart from hopefully restraining the more alarmist statements in the media on getting rid of coal, these results should also dampen ill-informed expectations that the simultaneous rapid reduction of air pollution and CO2 emissions is somehow a cost-saving exercise that would benefit developing countries.

Growing gap between climate science and climate policy

But the true value of the report to the fate of humanity depends very much on the willingness of the political leadership of the Global North to read the message as it should be done and not twist it to their own partisan ends.

One may argue that this is not a novel situation and that this has indeed been the true story of the tremendous inaction on climate that has increasingly characterised the approach of the rich nations of the world while the climate crisis has been steadily intensifying. Successive assessment reports of the IPCC, issued every five years in four volumes, have undoubtedly spurred fresh global policy initiatives, especially in the pre-eminent multilateral forum for global climate action, the United Nations Framework Convention on Climate Change (UNFCCC). This is a message that is frequently heard in the general hype of the climate commentariat that accompanies every new report of the IPCC. But a more critical view would also argue that, for the last two decades out of the three since the UNFCCC’s entry into force, these initiatives have been increasingly about forcing the Global South into bearing the burden of meeting the global warming challenge. Equally, they have been less and less about concerted and determined action by the Global North to meet their responsibilities and commitments, inaction that has sharply reduced the South’s options even for poverty eradication, let alone overall development.

This dismal record clearly began with the publication of the IPCC’s Fourth Assessment Report (AR4) – which unambiguously pronounced that global warming was anthropogenic in origin and that this warming was unequivocal – that heralded a shift in policy at the 13th Conference of the Parties (COP 13) to the UNFCCC, the annual climate summit held at Bali in 2007. Perversely though, Bali turned its back on the unambiguous statement that developed countries ought to take the lead in mitigating GHG emissions with legally binding commitments embodied in the Kyoto Protocol, and heralded the consistent recalcitrance of the developed countries in undertaking such commitments.  Led by the United States, they have since evaded truly meaningful action, until assured that China, India and indeed all developing countries would make equally onerous mitigation commitments, contra the flexibility provided by the climate convention itself.

The Fifth Assessment Report (AR5) reinforced the messages of AR4 and provided an extraordinarily simple metric, namely global cumulative emissions and their linear relation to global temperature rise, for assessing the boundaries for humanity’s safety. Based on this relation, the AR5 indicated that humanity had to live within a global carbon budget, whose limit, subject to uncertainties, was determined by the temperature target. The Paris Agreement, signed at COP 21 in 2015, was clearly profoundly influenced by this particular result – but relentlessly chose to turn its back on this result in essence.

On the one hand, the AR5 paved the way, for the first time, for turning away from diffuse targets of atmospheric GHG concentrations towards specific temperature targets. The Paris Agreement thus set two targets – to limit temperature increase from pre-industrial levels to well below 2°C, and further to try and restrict it to 1.5°C. But the Agreement studiously avoided any talk of limiting global cumulative emissions to a definite global carbon budget, and its obvious corollary of distributing this global budget among all Parties on the basis of equity and the principle of common but differentiated responsibilities. Instead, it allowed all Parties, including the developed countries, to undertake commitments of their choosing, the so-called nationally determined contributions (NDCs). The adequacy of such commitments in relation to the temperature targets was left to their being progressively increased in the future.

However, to allow themselves considerable flexibility in future emissions, the developed countries argued instead for voluntary declarations of a peaking year for emissions, together with a global goal of reaching net-zero emissions by the second half of the century. It is an elementary mathematical fact that these two restrictions are not sufficient to limit cumulative emissions, and hence both may be met even while temperatures are set to definitely cross the 1.5°C or the ‘well below’ 2°C targets set by the Paris accord, especially when read with the proposed NDCs, whose inadequacy was apparent even before the accord was signed.

The gap between climate policy and science was indeed worsened when the IPCC undertook the preparation and publication of a Special Report on Global Warming of 1.5°C, issued in 2018. While the Special Report undoubtedly made the case, perhaps a little ambiguously, for the desirability of the 1.5°C target as opposed to 2°C, the case for its feasibility was hardly as clear. Apart from generalities on the profound, transformative changes required to realise the lower target, the Special Report had little to say on the socio-economic and policy constraints on attaining this goal. Subsequently the Global North has launched a vociferous campaign in support of this goal, diluting the carefully crafted ambiguity of the Paris Agreement and supported by an unwary coalition of small island states and least-developed countries that have paid little attention to the rapidly diminishing global carbon budget that is pushing the target out of reach.

Carbon budgets and the myth of net zero exposed

The latest IPCC report on the physical science, which is the first of the four volumes that will make up the AR6, emphatically points once again to the linear relationship between cumulative emissions and rise in global surface temperature.

From 1850 till 2019, notes the report, approximately 2,390 gigatonnes (1 gigatonne is scientific terminology for 1 billion tonnes) of carbon dioxide (GtCO2) were emitted, and this was responsible, along with lesser contributions from other GHGs, for an increase in global surface temperatures of about 1.07°C (likely range of 0.8-1.3 °C) compared with pre-industrial times.

The report also provides detailed estimates of carbon budgets, with different probabilities for varying temperature targets. For instance, for a 50% probability of limiting temperature rise to below 1.5°C, the total carbon budget available to the world (from pre-industrial times till net-zero emissions are achieved) is 2,890 GtCO2.

Given the cumulative emissions to date, this implies that more than 80% of the carbon budget for the 1.5°C target is already exhausted and that the world has only 500 GtCO2 of emissions left at its disposal. Global emissions databases tell us that developed countries have been responsible for over 60% of these past emissions and China for about 13%. India’s contribution to these cumulative emissions to date is only 5%. There is greater headroom with a higher temperature target; for a 50% probability of keeping temperature rise to below 2°C, the remaining carbon budget is 1,350 GtCO2.

These estimates in the report provide a much-needed perspective on the pressure for net-zero emissions declarations, typically setting 2050 as the target date, that currently threatens to overwhelm the entire discussion on climate change mitigation. In the narrative assiduously peddled by the Global North and their developing-country apologists, unwitting or otherwise, declaration of a net-zero emissions target is portrayed as an almost heroic climate action, while any argument questioning such targets has been sought to be rendered suspect.

But the reality is starkly different. For a 50% chance of limiting temperature rise to below 1.5°C, the world will have to begin reducing emissions immediately and reach net-zero emissions by 2039. For a better likelihood, for instance 67%, of limiting temperature rise to below 1.5°C, the world has to reach net zero even earlier, by 2035.

While most developed countries are still only discussing reaching net-zero emissions only by 2050, few have actually declared this in a manner that is verifiable by multilateral agreement. But even those who have are targeting net zero so far into the future that it ensures that the 1.5°C target will not be met. Even if one assumes that these countries will begin immediate emissions reductions and at a linear rate to meet their declared net-zero targets, they will still end up emitting at least 270 GtCO2 by 2050. This is more than 50% of the remaining carbon budget for the 1.5°C target. Thus the developed world, with only about 18% of the global population, is likely to usurp fully half the space available for remaining cumulative emissions, while the remaining 82% of the world, having emitted very little in the past, will be left with little in the future to meaningfully satisfy their energy requirements.

The IPCC report is therefore an important wake-up call to the world for a very different reason than popular narratives would have us believe. It is a call to not get taken in by the claim that net-zero declarations of developed countries represent ‘ambition’ in climate action. The message of the report is that the real question to be asked of countries is how much they plan to emit cumulatively from now till they reach net zero and whether this is in keeping with their fair share of the carbon budget. Progress towards achieving meaningful climate action requires that the world start asking the right questions.

Crossing the 1.5°C threshold in all scenarios

The IPCC report also assesses climate responses to five emissions scenarios, noting that these scenarios are only illustrative – a result of model simulations and not representing real emissions trajectories which may be influenced by multiple factors. These five emissions scenarios represent five different levels of radiative warming, from the very low to the very high.

A stark finding of the report is that the 1.5°C target is likely to be exceeded at least in the near term, under all five scenarios considered. Even in the lowest emissions scenario, the likely range of temperature increase in the near term (2021-40) is about 1.5°C, increasing to about 1.6°C in the mid-term (2041-60), and only declining to 1.4°C in the long term (2081-2100). A very significant assumption of this scenario is that negative emissions, meaning the drawing out of carbon dioxide from the atmosphere by artificial means, will be possible on a significant scale beyond 2050. But the large-scale deployment of a range of such carbon dioxide removal technologies, most of which are as yet mere speculation, according to the IPCC report itself is likely to also have a number of negative side-effects.

Despite the vociferous campaign for limiting temperature rise to 1.5°C, there is clearly little hope that this expectation can be met. Perhaps, in reaction to this dismal state of affairs, some scientists have turned to mapping out several possible scenarios of very low likelihood but potentially very high impact. These scenarios find some space in the IPCC report, though freezing oneself with fear of an apocalyptic future seems less than useful, when the real issue is the lack of political will for climate action in the present.

In sum, there is no doubt that rapid and sustained reductions in global emissions are needed. That rich countries are responsible for a significant proportion of these emissions is a statement of fact. Their current and proposed climate actions are highly inadequate and will likely result in temperature rise that is higher than the Paris Agreement targets. Even with disproportionately greater action from developing countries such as India, as is already forthcoming, it is unlikely that temperature rise will remain below 1.5°C unless the richest countries and highest emitters do far more than what they are currently doing or are committing to do in the future.

Declarations of ‘climate emergency’ or rhetorical references to a ‘climate crisis’ mean nothing unless such statements are backed by necessary action. The IPCC’s assessment shows that the world needs rapid reductions in emissions by developed countries accompanied by the phasing out of all fossil fuel use (coal, oil and natural gas), large-scale investment in technologies and their deployment, and the mobilisation of adequate climate finance to support climate action – both adaptation and mitigation – in developing countries.                

Tejal Kanitkar is Associate Professor at the National Institute of Advanced Studies in Bengaluru, India. T Jayaraman is Senior Fellow, Climate Change, at the MS Swaminathan Research Foundation in Chennai, India. This article first appeared in Frontline (10 September 2021).

*Third World Resurgence No. 348, 2021, pp 11-14