In recent years, the communication of climate science has increasingly faced the challenge of effectively conveying probabilistic forecasts to the public. A new study illuminates how the choice of language, particularly the use of verbal probabilities with inherent directionality, can profoundly shape public perceptions of scientific consensus, evidence strength, and personal concerns about climate change. This groundbreaking research, conducted with a representative sample of UK residents, delves into the nuanced psychological impacts of how climate projections are framed, offering essential insights for scientists, communicators, and policymakers seeking to foster informed public engagement.
The research team designed an elaborate experiment involving 872 UK participants, carefully selected to mirror the nation’s demographic distribution by gender, age, and political voting preferences. Their objective was to assess how verbal expression of probabilities—in this case defined by ‘directionality’, which refers to the framing of outcomes in either positively or negatively valenced terms—affects the perceived credibility and urgency of climate impacts. Specifically, the scientists manipulated projections of temperature increases and winter precipitation changes, two critical climate variables with different levels of public familiarity and expectation.
Temperature projections are relatively well understood by the public, representing a familiar point of reference for climate change discussions. In contrast, forecasts about winter precipitation shifts are less commonly interpreted with clarity by the average individual. By introducing these two dimensions—temperature and precipitation—the study taps into the interplay between established knowledge and novel information, creating a robust test bed for exploring how directionality influences cognitive and emotional responses towards climate data.
Critically, the study integrated a second experimental manipulation focused on greenhouse gas (GHG) emission scenarios: low versus high emissions. Low-emission projections typically reflect more optimistic or aggressive mitigation outcomes and are often at odds with the public’s existing beliefs. High-emission scenarios tend to align with current trajectories or pessimistic expectations, serving as a contrasting baseline. This dual manipulation of both linguistic framing and emission intensity provides a rare, multidimensional view of how preconceptions and language intersect to shape climate change communication.
Empirical results reveal clear patterns for temperature projections. When probabilities were framed using positive directionality—for instance, suggesting a ‘small probability’ of increase rather than an ‘unlikely’ chance—participants attributed significantly greater consensus among scientists and judged the underlying scientific evidence as stronger. Correspondingly, their expressed personal concerns about climate change rose measurably. Such findings demonstrate that positive verbal probabilities enhance the perceived credibility and seriousness of temperature rise projections, translating into heightened concern.
Interestingly, the study indicates that the impact of directionality on perception was notably more pronounced under low GHG emission conditions. This suggests that when participants were confronted with projections that contrast strongly with their expectations—such as unexpectedly low temperature increases—the framing effect gains more power. Conversely, for high-emission scenarios where projections accorded more closely with participants’ prior beliefs, the effect of verbal direction was attenuated or even became statistically insignificant. This interaction underscores how cognitive biases and expectation frameworks modulate the reception of scientific information.
For winter precipitation projections, the pattern of results diverged somewhat. Directionality still influenced levels of concern but to a lesser extent and without the same cohesive effects on perceptions of consensus and evidence strength observed for temperature trends. The comparatively smaller and less consistent effects may stem from lower public familiarity with winter rainfall projections, engendering a weaker baseline mental model from which to evaluate probabilistic language. This highlights the crucial role of domain knowledge in mediating the impact of communication strategies.
Underpinning these findings is the broader psychological mechanism of expectancy violation. When climate outcomes are framed in a way that matches or exceeds participants’ anticipations—such as high GHG emissions predicting substantial increases—directionality introduces minimal shifts in belief or attitude. However, framing outcomes that challenge expectations—like low emissions scenarios suggesting modest impacts—in a positive or negative verbal probability framework causes greater shifts in perception. This dynamic reveals the complex interplay between informational content, linguistic tone, and preexisting mental models in shaping public understanding.
The study also sheds light on the subtle but powerful nature of verbal probabilities relative to numeric counterparts. Verbal probabilities, being inherently ambiguous and context-dependent, offer a potent vehicle for framing effects. Words like ‘unlikely’ versus ‘small probability’ carry distinct emotional and cognitive connotations that color how data is internalized. This linguistic nuance is particularly consequential in the climate arena, where scientific uncertainty and probabilistic forecasting are intrinsic but must be communicated without diminishing perceived urgency or trustworthiness.
Importantly, the researchers took care to contextualize their findings within a representative UK sample, addressing political, social, and demographic diversity. This enhances the ecological validity of the results, implying that the observed effects are likely generalizable across broad segments of the public rather than confined to niche groups predisposed to climate skepticism or activism. Thus, the insights offered are crucial for designing communication campaigns that resonate across diverse audiences.
In practical terms, the data gleaned calls for a reconsideration of how climate scientists and communicators articulate future projections. Employing positively valenced verbal probabilities—carefully calibrated according to emission scenarios and public familiarity—may enhance the perceived legitimacy and urgency of climate risks. Conversely, reliance on negative or ambiguous verbiage risks undermining consensus-building and dampening concern, potentially slowing societal momentum towards mitigation and adaptation efforts.
The findings also caution against a one-size-fits-all approach to scientific communication. Because the effects of verbal probability framing hinge on preexisting beliefs and knowledge, tailored messaging strategies are required. For audiences well versed in climate science, subtle linguistic shifts may have marginal influence, whereas for less informed or more skeptical groups, communication framing could represent a decisive factor in shaping attitudes and behaviors.
Another striking aspect of the research is its methodological rigor, combining precise experimental controls with detailed statistical analysis. The authors employed independent t-tests to quantify differences between conditions, while confidence intervals and significance levels delineated the strength and reliability of effects. This statistical robustness lends confidence to the conclusion that verbal directionality exerts a causal influence on climate-related perceptions and concerns.
More broadly, the study contributes to a growing body of evidence recognizing the pivotal role of language and cognition in the public understanding of complex scientific issues. As climate change messaging navigates an increasingly polarized information landscape, fine-tuning the verbal coding of probability and uncertainty emerges as a vital lever in influencing societal readiness and policy support. This research lays foundational groundwork by empirically demonstrating that subtle verbal nuances can have outsized impacts on collective climate consciousness.
In summary, this pioneering experiment reveals that negative verbal probabilities systematically weaken the communication of climate science by diminishing perceived consensus and evidence strength, as well as personal concern, especially when projections contradict prior beliefs. By contrast, positive directionality in verbal probabilities bolsters these perceptions, particularly under low emission scenarios and for well-understood variables like temperature change. These insights inform the design of clearer, more persuasive climate communication strategies that can better mobilize public engagement and action.
As governments and organizations worldwide strive to convey the urgency and nuance of climate projections, this research underscores the importance of linguistic precision and psychological insight. Harnessing the power of positive verbal framing aligned with audience expectations could accelerate the translation of scientific understanding into meaningful societal response, bridging the gap between climate knowledge and climate action.
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Subject of Research: Impact of verbal probability framing on public perceptions of climate change science and risk.
Article Title: Negative verbal probabilities undermine communication of climate science.
Article References:
Juanchich, M., Teigen, K.H., Shepherd, T.G. et al. Negative verbal probabilities undermine communication of climate science. Nat. Clim. Chang. (2025). https://doi.org/10.1038/s41558-025-02472-1
DOI: https://doi.org/10.1038/s41558-025-02472-1
Image Credits: AI Generated
