

Until the mid-sixteenth century, navigation on the high seas was complicated by the then-maps not aligning with compass bearings, making it necessary for sailors to perform constant course correction.
In 1569, Flemish cartographer Gerardus Mercator introduced a transformative map projection that enabled sailors to plot a single heading and hold it for an entire voyage. However, the map was imbued with the curious feature of dramatically inflating northern landmasses, making Europe and North America appear much larger relative to Africa and South America.
In the centuries that followed, the Mercator projection migrated from ships to classrooms, becoming the standard in textbooks worldwide. The distortions in continental size in these maps shaped the geographical intuition of generations of students, unwittingly embedding a Eurocentric worldview.
This anecdote contains an enduring lesson: even purely technical choices, made without ideological intent, can quietly encode worldviews and shape distorted perspectives when wielded in a different context.
This lesson is pertinent in the wake of the just-released 2026 Environmental Performance Index (EPI) – one of the world’s best known environmental rankings widely cited by governments, media, and international institutions.
EPI-2026 ranks European countries as the world’s best environmental performers with the bottom ranks occupied almost exclusively by countries from the Global South.
What often goes unrecognised is that any such index is highly contingent on subjective choices made in constructing them. Choices such as which indicators to include, how to weigh them, and what benchmarks to apply. While these choices are often framed as purely technical decisions, they inevitably encode value judgements with real world implications.
For instance, EPI-2026 ranks the United States 43rd among 177 countries on climate performance — a fairly high ranking for the world’s largest historical emitter.
In sharp contrast, the 2026 Climate Change Performance Index (CCPI) – another well-regarded index produced by German Watch and the New Climate Institute ranks the US among the three worst performers alongside Saudi Arabia and, ironically, Iran.
Why do two credible, science-based indices arrive at such divergent verdicts on the same countries? What does that tell us about a country’s “true” climate performance?
A recent paper by the authors of this article, published in the journal Climate Policy, traces much of this divergence to an important design choice embedded in each index’s methodology: how much weight it assigns to a country’s total emissions versus its emissions per person.
The EPI’s climate change module leans toward the first approach. It is grounded in the physics of the atmosphere that only responds to the total stock of greenhouse gases accumulating in it, which means that a country’s absolute emissions are all that matter.
By this logic, industrializing countries are penalized for their increasing emissions regardless of their historical or developmental context; for instance, infrastructure development in ‘developing’ countries, which are undergoing rapid urbanization, will inevitably have high greenhouse emissions. This approach partially embodies the ‘polluter pays’ principle.
The CCPI leans toward the second approach, which is grounded in the ethical principle that every person has an equal claim to the atmosphere as a shared, finite resource. This logic penalizes affluent countries for their high emissions per person no matter the scale of their absolute country-wide emissions.
Thus, the reason that these indices yield divergent results is not because either is fallacious but that they ask fundamentally different questions: “is this country’s marginal contribution to global warming rising or falling?” versus “is this country appropriating more than its fair share of the atmospheric commons?”
To see how this choice moves the needle, our Climate Policy paper built a modified version of the EPI’s climate-change module, replacing just its two most heavily weighted indicators with fairness-based equivalents while leaving the rest of the index’s architecture untouched.
The effect was striking, with European countries performing best on the original-EPI moving to the bottom half on the modified, fairness version we created.
If the premise defines the answer, then the real fallacy is to treat any index as a neutral, scientific verdict. It is, in fact, an intrinsically value-laden exercise that reflects implicit choices about what is considered fair, urgent, and measurable by the index developers.
No single index can lay claim to an objective representation of the best and worst climate performers any more than a single map projection can claim to be the best representation of the world.
This isn’t merely an academic issue. In 2022, the Indian government rejected the EPI as “unscientific”; in 2019, the then-Australian prime minister dismissed the CCPI on similar grounds. Both, in effect, were objecting to a normative framing dressed up as a factual verdict, not to an error in the data. The reality is that the choice of which index to create, or to trust, is itself a subtly political act.
Ultimately, we must internalise the fact that multiple perspectives, seemingly irreconcilable, can often co-exist for complex social-environmental problems, yet each defensible on its own terms.
The debate on climate performance, then, would be better served if index developers examined the ramifications of their design choices, and stated them transparently. Likewise, governance institutions, policymakers, and the media should resist the allure of any single index and instead consult a range of indices representing multiple perspectives to arrive at a more nuanced understanding. For instance, India’s poor performance on the EPI may be read as an imperative to reduce its emissions, but its better performance on the CCPI may be read as an entitlement to international climate finance.
The Mercator projection distorted perceptions not out of malice, but because a tool built specifically for navigation was uncritically adopted for wider use. Environmental change is a far more polarized subject, and the choices involved in constructing an index, or in selecting which index to cite, may be driven by motives that are less benign.
Chirag Dhara is a sustainability scientist at Krea University, India. Kamal Murari teaches in the climate change programme at Tata Institute of Social Sciences, India. Sebastian Block led the 2024 cycle of the EPI and currently continues developing sustainability indicators at the Heidelberg Institute of Geoinformation Technology, Germany.
Originally published under Creative Commons by 360info™.