Psychologists have known for years that people’s assessments of the risks of climate change are strongly influenced by intense local weather and short-term temperature variability. A new study by Zaval and colleagues identifies the psychological processes that underlie such skewed assessments which are inconsistent with the long-term nature of climate change.
The authors tested three mechanistic hypotheses: 1) labels on choice options, 2) knowledge deficit, and 3) attribute substitution. The first hypothesis posits that people’s responses to questions are biased by the language used in the questions themselves, e.g. if questions use the term “global warming” instead of “climate change.” The second hypothesis posits that people’s attitudes towards climate change are shaped by the mistaken belief that short-term weather and long-term climate are highly correlated. The third hypothesis posits that people form opinions on the basis of less relevant but more salient and available data, like the temperature outside, rather than more relevant but less available data, like multi-decadal temperature and weather patterns. The authors only found evidence for the attribute substitution hypothesis and they concluded that abnormally hot or cold days cause people to preferentially recall other abnormally hot or cold days from memory, making people think such days occur more frequently thereby altering their attitudes towards climate change. Therefore, a central challenge of implementing effective national and international climate change policies will be convincing the public to focus on long-term climate trends rather than short-term weather patterns.
Zaval L, EA Keenan, EJ Johnson, EU Weber (2014) How warm days increase belief in global warming. Nature Climate Change 4:143-147