The atmosphere cares little for human concerns

This interview between physicist and climatologist Dr. Chirag Dhara and leading illuminem voice Praveen Gupta explores why climate rankings like the Environmental Performance Index and the Climate Change Performance Index can place the same country at opposite ends of the table, and what that reveals about the hidden ethical choices built into every index.

Dr. Chirag Dhara is a physicist and climatologist. His research interests involve climate science and impacts, and larger questions about the roots of the climate and ecological crises. Chirag's parallel concerns are equity and social justice, human and natural rights, non-anthropocentric "valuation" of nature, and environmental conservation.

He holds a PhD in Earth Science from the Max Planck Institute for Biogeochemistry and the University of Hamburg in Germany, and a PhD in Physics, having earlier worked in theoretical quantum mechanics and quantum communication.

Chirag co-authored India's first official climate assessment report in 2020 and was a contributing author to the IPCC AR6's Atlas (2021). He has also written on climate and sustainability in Scientific American, Nature India, 360info, The India Forum, Mongabay India, The Hindu, among others.

Praveen Gupta (PG): Can climate rankings really reveal which country is a good performer?

Chirag Dhara (CD): Yes, but with critical caveats, and no single climate index can provide a definitive answer. For instance, the 'Environmental Performance Index' (EPI) by Yale/Columbia universities has a climate module that rates India among the bottom third of countries it assesses. On the other hand, the 'Climate Change Performance Index' (CCPI) developed by German Watch rates India among the top third of the countries it assesses.

The reason indices can differ widely is because they are designed to answer a specific question. For instance, the EPI is effectively asking "is this country's marginal contribution to global warming rising or falling?" Whereas, the CCPI is asking "is this country appropriating more than its fair share of the atmospheric commons?"

Both are legitimate questions to ask and answer. Both are legitimate questions and both have defensible answers, which is why the same country can sit near the top of one table and the bottom of another.

Yet, most often, the underlying question that an index is designed to answer is not made evident. In fact, in our experience in talking to the developers of some major indices, the developers themselves may not be able to articulate the question that their index has been designed to answer. They can simply develop an index, making various design choices that they think are pragmatic and reasonable, without stopping to ask what their choices really mean.

The key issue at hand is that 'climate performance' is a complex socio-economic and political question that defies a singular answer. The indices can give perfectly reasonable answers to the specific question that they have been designed for. The problem is that we may disagree on the question itself!

Although we have quantified this notion with regards to climate performance in our research, I believe that this observation applies more broadly to a whole suite of socio-ecological problems.

"The key issue at hand is that 'climate performance' is a complex socio-economic and political question that defies a singular answer."

PG: Is there anything that stops environmental indices short of being objective?

CD: The data are usually as objective as we can make them. What is not objective is everything that surrounds the data: which indicators to include, how heavily to weight them, what benchmark counts as good, and what baseline year to measure from.

It helps to separate two kinds of decisions. Some are genuinely technical, such as whether to aggregate using an arithmetic or a geometric mean. Others may seem like a technical choice but, in fact, emerge from a worldview, perhaps not even consciously known to the index developer.

For instance, choosing to score countries on 'absolute emissions' or 'per capita emissions' (or some weighted combination of both) may seem like a dry technical choice but actually encode a moral understanding of the world. Do we fundamentally believe that every human being is equally entitled to the global commons (in the case of climate change, the atmospheric commons)? Or do we believe that affluent entities are entitled to more of the commons (a concept called 'grandfathering')? These are the loaded choices we analyse in our Climate Policy paper, which are ordinarily invisible to the lay reader of a ranking.

This is not a flaw that can be engineered away. Every index makes such choices. The problem arises when the resulting number is presented as an objective verdict rather than as an answer to a particular question.

PG: How is the EPI different from the CCPI?

CD: They differ in scope and in premise.

In scope, the EPI is much broader, covering nearly 180 countries across climate, environmental health, and ecosystem vitality. The CCPI covers around sixty and confines itself to climate, adding an expert assessment of national policy.

In premise, the EPI's climate module is built around absolute and projected greenhouse gas emissions. That rests on a physical fact: the atmosphere responds only to the total stock of gases accumulating in it, and is indifferent to whether a tonne of carbon came from a private jet or a cement plant serving first-time electricity users. The CCPI assesses countries on their emissions per person, which follows from the ethical premise that every individual has an equal claim on a finite shared resource.

Hence the mirror images. Morocco sits in the bottom third of the EPI's climate scores and among the best few on the CCPI. The United States sits in the upper quarter on the EPI and among the worst on the CCPI. Neither index has made an arithmetic error.

"India's air pollution, water contamination, biodiversity loss, and waste management failures are real, and pose a severe risk to public health in India."

PG: Do you believe European countries are the world's best environmental performers and the Global South the worst?

CD: I believe that is what the EPI measures, and that the result is defensible on the EPI's own terms. I do not believe it is a fact of nature.

In our paper, we constructed a fairness-adjusted version of the EPI's climate module: we retained the mathematical structure of the EPI but modified two terms within it that operationalised a strong-equity principle. We then ran the same data that the EPI uses. The effect was striking, the rankings inverted with South Asia and Africa rising sharply in the rankings, and much of Europe falling to the bottom.

That said, I would resist the comfortable conclusion that poor scores are merely artefacts. India's air pollution, water contamination, biodiversity loss, and waste management failures are real, and pose a severe risk to public health in India. Europe's strong showing on environmental health is partly bought by wealth and technological advances, partly through decades of monitoring and regulation, and partly through environmental colonialism, transferring hazardous waste to the Global South such as e-waste to Ghana and Nigeria, plastics to Turkey, deforestation to Brazil and Indonesia, etc. Can any country or bloc that is unwilling to handle its own pollution and waste be named a stellar model for others to emulate?

PG: Are industrialising countries penalised for their increasing emissions regardless of historical or developmental context?

CD: Yes, they are, although perhaps a less-loaded word than 'penalised' may be more appropriate.

Objectively, it is indeed the case that the EPI ranks currently industrialising countries much lower because their emissions are increasing. In the process, the EPI makes no distinction between a country building housing, roads, and grid capacity for its population, and one in which people own private jets and yachts. Agarwal and Narain drew attention to this issue thirty-five years ago when they made the distinction between luxury emissions of the rich and survival emissions of the poor.

Having said that, there also remains the fact that the atmosphere itself only responds to absolute emissions and cares little for human concerns around equity and justice. The more the concentration of GHGs in the atmosphere, the more the Earth warms, and the more the climate changes. That change in climate affects the non-affluent countries hardest.

Which is why there are no convenient or singular answers. Being intellectually honest requires that we hold both truths simultaneously, uncomfortable as it may be.

"We constructed a fairness-adjusted version of the EPI's climate module… The effect was striking – the rankings inverted with South Asia and Africa rising sharply in the rankings, and much of Europe falling to the bottom."

PG: Are total emissions and per-person emissions the only two parameters? Would you propose an alternative?

CD: No, and we were explicit that we chose this binary in our paper as a simplification in the spirit of Occam's Razor. It was adequate for interrogating the three indices we examined, not for exhausting the subject.

Several other principles have a claim: capability, meaning the resources a country can actually bring to bear; the right to development; moral as distinct from causal responsibility; political feasibility; and vulnerability and adaptation need, which mitigation-focused indices largely ignore.

The alternative is not another index. Every index we build will privilege some perspectives at the expense of others, so adding one more to the pile changes little. What would help is modular indices whose components can be recombined, published alongside a plain statement of the principles they encode, and read as a nuanced narrative rather than a single objective truth.

PG: Should index developers examine and state the ramifications of their design choices?

CD: Yes, and I would put it more strongly: the goal is not methodological neutrality, which is unattainable, but conscious transparency, which is indeed attainable.

Four things would make a practical difference. Documentation that sets out the normative premises alongside the methods, rather than presenting rankings as objective assessments. Interactive tools letting users see how rankings shift when different principles are emphasised. Audits that test for embedded worldviews, in the way existing audits already test for statistical validity. And explicit comparison with indices built on contrasting premises, so that divergence is explained by the developers.

The absence of such statements is precisely what allows an index to be projected as a scientific verdict and rejected as a political attack, which is roughly the exchange India and the EPI's developers had in 2022.

PG: Do rankings get in the way of resolving a global existential threat? Are we not all in the same boat?

CD: We are in the same storm but not in the same boat.

Rankings do cause harm when they are wielded as rhetorical instruments, and both sides do the wielding. A government can dismiss an unwelcome index as unscientific; an index can be cited abroad as proof of a country's bad faith. Thailand's response to a poor EPI score is the more instructive path: it studied the methodology, assigned agencies to report against the indicators, and folded the framework into planning.

Even that carries a risk. Once an indicator becomes the target of policy rather than a proxy for a more complex reality, it risks being gamed. We see this all the time with universities trying to game well-known university rankings, etc. In that sense, rankings may indeed get in the way of resolving a global threat.

At the same time, used carefully, disagreement between indices can be informative rather than obstructive. It shows exactly where the ethical fault lines in climate negotiation lie.

PG: Many thanks Chirag! You demystify some of the knotty mysteries around the climate breakdown with such clarity. My best wishes in all your endeavours.

This article is also published on The Diversity Blog. illuminem Voices is a democratic space presenting the opinions of leading Sustainability Thought Leaders, their views do not necessarily represent those of illuminem.

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