When Science Becomes Political Identity
Imagine sitting with a baseball fan and asking a seemingly straightforward question: “Do you believe in batting averages?” The person would probably look at you as though you knew nothing about baseball. A batting average is a statistic, not a matter of belief. It measures something observable, and the interesting questions concern what the number reveals about a player's performance.
Now imagine telling that same person that batting averages cause home runs or strikeouts. The reaction would likely be similar. A batting average doesn't cause anything. It describes the results of events influenced by the player's abilities, opposing pitchers, playing conditions, and numerous other factors.
Yet remarkably similar language became commonplace in discussions about climate change. “Do you believe in climate change?” became a recurring question in political interviews, campaign debates, and public discourse. It was often treated as a test of whether someone accepted science, rather than an invitation to discuss scientific evidence. The question became so closely associated with political identity that the response could seem more important than the reasoning behind it.
The problem begins with the terminology itself. Climate is a statistical description of weather over time, including patterns in temperature, precipitation, and atmospheric conditions. Climate change refers to changes in those patterns. Like a batting average, it is something to measure, investigate, and explain rather than simply believe or disbelieve.
The analogy extends to another familiar expression: “Climate change causes this” or “climate change causes that.” Strictly speaking, climate change is not an independent physical force. Greenhouse gases, ocean circulation, atmospheric conditions, land surfaces, and other processes influence weather and the climate system. Changes in those processes can alter the frequency or intensity of particular weather events. Scientists reasonably use “climate change” as shorthand for these effects, but the phrase can become misleading when it replaces an explanation of the mechanisms involved.
A more useful discussion would ask whether a particular event has become more likely or more intense because of human-induced warming, how strong the evidence is, and what other influences contributed. Those questions require statistical analysis, physical evidence, and an acknowledgment of uncertainty. They cannot be answered simply by declaring belief.
None of this means that anthropogenic global warming is scientifically unsettled. The evidence that human activity has warmed the planet is exceptionally strong. But accepting that conclusion does not require treating every claim about future temperatures, extreme weather, or environmental consequences as equally certain.
Somewhere along the way, however, climate change became more than a scientific subject. It became a political identity. The language of belief divided the public into opposing camps, while the complexity of the underlying research was increasingly compressed into competing narratives.
The result is a peculiar situation: a field built upon measurement, probability, and scientific uncertainty is frequently discussed as though its conclusions must fit into a simple declaration of allegiance. Several important examples reveal just how much context can disappear in that process.
What the Science Establishes
The fundamental evidence for human-induced global warming is not particularly ambiguous. Global surface temperatures have increased since the nineteenth century, atmospheric carbon dioxide concentrations have risen substantially, and the oceans have accumulated enormous quantities of additional heat. The Intergovernmental Panel on Climate Change (IPCC) concludes that human influence has unequivocally warmed the atmosphere, ocean, and land.
Carbon dioxide from fossil-fuel combustion is the largest individual contributor to long-term human-induced warming. Methane and other greenhouse gases add to that influence, while certain forms of air pollution have partially offset it through cooling. Natural variability and regional conditions further influence how warming appears in the observational record.
These distinctions are important because climate science does not assign the same level of certainty to every finding. Establishing that human activity is warming the planet is different from determining precisely how much a particular hurricane, drought, heat wave, or flood was influenced by that warming. The strength of the evidence varies by phenomenon, location, and time period.
Understanding those differences is not a rejection of climate science. It is part of understanding the science itself.
RCP8.5: How a Scenario Became a Predicted Future
One of the most consequential examples of scientific information losing its context involves RCP8.5, a high-emissions scenario developed to examine how the climate might change under a future of continued heavy fossil-fuel use. It was one of several pathways researchers could use to explore different possibilities. It was not a prediction of where the world was inevitably heading.
Yet over the following decade, that distinction became increasingly blurred. RCP8.5 was frequently described as “business as usual,” suggesting that its assumptions represented the trajectory the world was already following. The characterization appeared in peer-reviewed research, where the scenario was used to project everything from future heat waves and agricultural losses to flooding and economic damage. Politicians, journalists, and environmental organizations then drew upon these findings, sometimes presenting the resulting projections as warnings about what the future would bring if the world continued on its present course.
The problem was not that scientists examined a high-emissions future. Such scenarios are useful for understanding extreme risks. The problem was that a conditional scenario increasingly became a presumed future, and its projected consequences helped shape public perceptions of climate change. Over time, RCP8.5 became an influential foundation for research and public narratives about the severity of future warming, even though its assumptions were increasingly at odds with developments in energy markets, technology, and emissions trends.
By January 2020, climate researchers Zeke Hausfather and Glen Peters were openly challenging this practice. In an article published in Nature, they argued that RCP8.5 should not be presented as the most likely emissions trajectory and warned against treating the highest-end scenario as business as usual. Their concern was consequential: overstating the likelihood of extreme outcomes could distort public understanding and produce poorly informed policy decisions.
The issue was also debated within the scientific community. Other researchers defended the continued relevance of RCP8.5, particularly for examining cumulative emissions and high-end climate risks. But the IPCC's Sixth Assessment subsequently emphasized that such high-emissions pathways should not be treated as typical business-as-usual projections.
The evolution of climate scenarios has continued. The newer CMIP7 framework incorporates updated assumptions about economic development, energy technology, and future emissions, including a highest-emissions pathway below the earlier RCP8.5 trajectory. These revisions do not eliminate the possibility of serious warming, nor do they invalidate research examining extreme outcomes. They demonstrate that the range of plausible futures changes as scientific knowledge and real-world conditions evolve.
What makes the RCP8.5 episode especially important is the distance that developed between a scientific scenario and the public narrative built around it. A model intended to explore what could happen became widely associated with what would happen. And once that interpretation entered research papers, news reporting, and political discourse, it acquired an authority that was difficult to unwind.
A scenario can be useful without being likely, and a projected consequence can be scientifically valid under its stated assumptions without being a reliable forecast of the future. That distinction should have remained central to the public discussion.
Aerosols: The Warming Effect of Cleaner Air
One of the more surprising findings in climate science is that reducing certain forms of air pollution can actually contribute to warming.
For decades, industrial emissions have produced two competing effects. Greenhouse gases have warmed the planet, while sulfate aerosols have partially cooled it by reflecting sunlight and changing the behavior of clouds. As governments have successfully reduced sulfur pollution, some of that cooling influence has disappeared.
The result is an environmental paradox rarely captured in the familiar narrative that reducing pollution necessarily reduces global warming.
This does not mean that sulfur pollution is beneficial overall. Sulfur dioxide contributes to harmful particulate pollution, respiratory illness, and acid deposition. Reducing it produces substantial health and environmental benefits. But its removal also allows more solar energy to reach and warm the climate system, while much of the carbon dioxide accumulated over preceding decades remains in the atmosphere.
International shipping provides a revealing example. In January 2020, the International Maritime Organization implemented regulations reducing the maximum sulfur content of most marine fuels from 3.5 percent to 0.5 percent. The change substantially reduced sulfur emissions from ships traveling major ocean routes.
Those emissions had previously helped produce reflective aerosols and brighten certain marine clouds. Reducing them improved air quality but also diminished a source of cooling over the oceans.
Following the exceptional global and North Atlantic warmth of 2023, researchers began examining how much the shipping regulations might have contributed. A 2024 study by Tianle Yuan and colleagues suggested that the reduction in shipping aerosols had produced a meaningful warming influence. Other researchers estimated smaller effects and emphasized that the changes could explain only part of the observed temperature anomalies.
The disagreement illustrates an important distinction. Scientists can be confident that reducing reflective aerosols produces a warming influence without knowing precisely how much that influence contributed to a particular year's temperature.
The shipping regulations did not suddenly become the principal cause of global warming. Long-term greenhouse-gas accumulation remained the dominant underlying influence, while ocean variability and other factors contributed to the unusual conditions of 2023.
But the episode complicates a familiar public narrative. Industrial emissions do not all affect temperature in the same direction, and successful environmental regulations can produce competing outcomes.
The broader lesson is not that cleaner air is undesirable. It is that environmental systems are complicated enough that even beneficial interventions can have consequences that run contrary to public expectations.
What Rising Temperatures Actually Tell Us
When people hear that average temperatures have increased, they often imagine that every region is becoming progressively hotter in much the same way. Yet the historical record reveals a considerably more complicated picture.
Warming has not occurred uniformly across the United States. Alaska has experienced some of the country's most pronounced temperature increases, consistent with the broader pattern of Arctic amplification. Many northern and western states have also warmed substantially. Parts of the Southern Plains and Southeast, however, have experienced comparatively modest warming over certain historical periods, particularly when daytime maximum temperatures are examined.
The differences depend on geography, season, the period selected, and the measurement used. A temperature trend beginning in 1970 may look different from one beginning in 1900. A regional average may conceal substantial differences among individual states, and an annual trend may differ from trends in summer or winter.
These qualifications rarely survive the transition from scientific data to a headline announcing that temperatures have increased by a particular amount.
An even more revealing distinction concerns the difference between daytime high temperatures and nighttime low temperatures.
When scientists calculate average daily temperatures, they commonly use information from both daily maximum and minimum temperatures. Yet these measurements have not always increased at the same rate. Across the United States, nighttime minimum temperatures have generally risen faster than daytime maximum temperatures over long historical periods.
The difference is especially pronounced in parts of the Southeast. The Fourth National Climate Assessment found that, since the middle of the twentieth century, average daily minimum temperatures in the region increased approximately three times faster than average daily maximum temperatures.
This is a significant finding because the phrase “rising temperatures” naturally brings to mind increasingly scorching afternoons. Yet in many places, an important component of the warming trend has been nights becoming less cold rather than daytime highs increasing at the same pace.
Warmer nights can have serious consequences. They reduce opportunities for the human body to recover from daytime heat, affect agricultural conditions, and increase demand for cooling. But those consequences differ from the effects of rising daytime maximum temperatures, and the distinction matters when interpreting the data.
Historical heat waves provide another example of why context is essential.
The extreme heat of the 1930s, particularly during the Dust Bowl, remains extraordinary in the American observational record. NOAA's U.S. Heat Wave Index identifies that decade as an exceptional period, with severe drought and atmospheric conditions producing some of the most intense heat waves recorded in the contiguous United States.
That history does not negate modern warming or the evidence that many heat extremes have become more frequent or intense. It does demonstrate that an extreme event can arise from several interacting influences and that historical comparisons depend on the measurement selected.
The number of days exceeding 95°F, the frequency of warm nights, the duration of heat waves, and annual average temperature are all meaningful statistics. But they do not necessarily follow identical trends.
This returns us to the baseball analogy. A player's batting average may increase, but that statistic alone does not tell us whether the change resulted from more singles, fewer strikeouts, or other factors. Likewise, an increase in average temperature establishes an important observation without fully explaining where the change occurred, whether it was concentrated in daytime highs or nighttime lows, or how extreme events have evolved.
The average is not misleading. Treating the average as though it describes the entire phenomenon can be.
Urban Heat, Sea Level, and the Importance of Geography
Local conditions introduce another layer of complexity that is easily overlooked when climate change is discussed in global terms.
Cities, for example, tend to be warmer than surrounding rural areas because buildings, pavement, reduced vegetation, and human activity alter how heat is absorbed and released. These urban heat islands can substantially increase the temperatures people experience, particularly overnight.
The phenomenon does not explain away global warming. Climate scientists use observational comparisons and statistical adjustments to limit urbanization's influence on global temperature records. But it does demonstrate that local development can contribute significantly to the heat experienced by communities, independently of the broader global temperature trend.
Sea-level rise provides an even more surprising example.
Global mean sea level is increasing as the oceans warm and land-based ice loses mass. Yet sea level does not rise uniformly around the world. Ocean circulation, changes in Earth's gravitational field, and vertical land movement can cause local relative sea-level trends to differ substantially from the global average.
NASA's research into sea-level fingerprints illustrates one of the less intuitive effects. Large ice sheets exert gravitational attraction on surrounding seawater. As those ice sheets lose mass, their gravitational influence weakens, redistributing ocean water. Consequently, sea level near a shrinking ice sheet can behave very differently from sea level thousands of miles away.
The land itself is also moving. Much of northern North America was once compressed beneath enormous ice sheets. Thousands of years after their retreat, some regions continue to rise as the crust and mantle adjust, while other areas experience subsidence. This process, known as glacial isostatic adjustment, can substantially influence local relative sea level.
The result is that two coastal communities may experience very different rates of relative sea-level change, even while the global average continues to rise.
Neither urban heat islands nor regional sea-level differences undermine the broader evidence of climate change. They demonstrate why global statistics cannot substitute for understanding local conditions. A measurement may be accurate at the global scale while providing an incomplete picture of what is happening in a particular community.
The Fossil-Fuel Paradox
The relationship between fossil fuels and climate change is another subject that has become deeply entangled with political identity.
The scientific evidence is clear that burning coal, oil, and natural gas releases carbon dioxide that contributes to long-term global warming. Yet fossil fuels have also played a central role in the development of modern industrial economies, supporting transportation, electricity generation, agriculture, manufacturing, and the infrastructure upon which contemporary living standards depend.
The same energy system that contributes to warming has also helped produce the economic resources, technological capabilities, and infrastructure that allow societies to respond to environmental challenges.
This creates a paradox that is difficult to capture within narratives that treat fossil fuels exclusively as either indispensable engines of prosperity or environmental threats.
Their effects operate in several directions:
Fossil-fuel combustion → CO₂ → warming.
Fossil-fuel combustion → sulfate aerosols → cooling.
Fossil-fuel energy → economic and technological development → greater adaptive capacity.
Fossil-fuel energy → cumulative emissions → greater long-term climatic forcing.
These effects are not equal in magnitude or duration. Sulfate aerosols are relatively short-lived, while accumulated CO₂ produces a much longer-lasting warming influence. Economic development does not cancel the physical effects of greenhouse gases, and technological progress does not eliminate every climatic risk.
Nevertheless, the broader relationship between fossil fuels and human vulnerability is more complicated than their warming influence alone.
Modern energy systems, including renewable technologies and nuclear power, have developed within industrial economies that remain partly dependent on fossil fuels. The manufacturing, mining, transportation, and construction needed for an energy transition are themselves supported by existing energy infrastructure.
Recognizing this does not establish that fossil fuels should remain dominant indefinitely. Nor does it determine the appropriate pace of an energy transition. Those are broader questions involving engineering, economics, energy security, technological development, and public policy.
The distinction matters because identifying the physical cause of a problem does not automatically establish the optimal policy response. Scientific evidence can clarify consequences and tradeoffs, but political decisions also involve competing priorities and judgments about how those tradeoffs should be managed.
Once again, the difficulty emerges when a complicated relationship is reduced to a simple political narrative.
When Evidence Becomes Allegiance
The examples examined throughout this essay share a common characteristic. In each case, the underlying scientific findings contain qualifications that can substantially change how the results should be understood.
RCP8.5 was a conditional high-emissions scenario, yet it became widely associated with an expected dystopian future. Aerosols demonstrate that reducing certain pollutants can remove a cooling influence even while improving public health. Regional temperature records show that warming is uneven, while the difference between nighttime lows and daytime highs reveals that a single average can conceal important changes in the underlying data.
Urban heat islands and sea-level fingerprints demonstrate that global trends do not describe every local condition. Fossil fuels illustrate how an activity can contribute to climatic hazards while also supporting the technological and economic capacity needed to respond to them.
None of these observations disproves human-induced global warming. That is not their purpose. Their significance lies in demonstrating how much information can be lost when complex findings are compressed into simple public narratives.
And this brings us back to the question that became so prominent in political discourse: “Do you believe in climate change?”
The question is revealing because it asks for a declaration rather than an explanation. It turns a scientific subject into a test of identity, implying that the central issue is whether someone belongs to the camp that accepts climate change or the camp that rejects it.
Once a scientific subject becomes a marker of political allegiance, nuance can become inconvenient. Qualifications that would ordinarily demonstrate intellectual rigor may instead be interpreted as signs of disloyalty. A researcher who questions whether RCP8.5 represents a plausible future can be mistaken for someone questioning climate change itself. Someone who points to the extraordinary heat waves of the 1930s may be assumed to be dismissing modern warming.
The problem also operates in the opposite direction. Those skeptical of climate policy may selectively emphasize historical heat waves, regional temperature differences, or uncertainty in climate projections to suggest that the evidence for human-induced warming is much weaker than it actually is.
Both tendencies replace scientific inquiry with ideological interpretation. Evidence becomes something to defend or attack rather than something to examine.
Perhaps that is what makes the question “Do you believe in climate change?” so revealing. It reduces a complicated scientific subject to a declaration of allegiance, when the meaningful questions have always concerned what the evidence establishes, what remains uncertain, and how the findings should be interpreted. Climate change deserves the same intellectual discipline we would expect of any other scientific subject: a willingness to follow the evidence wherever it leads, even when the conclusions complicate the narratives we have come to accept.