If climate change means higher temperatures, then what are people to make of the brutal cold that continues to cause havoc across the US? Or the fact that only three years ago the UK experienced one of its coldest Decembers for decades, if not centuries?

With public concern about climate change stalling in recent years, these might seem exactly the sorts of weather events likely to generate sceptical viewpoints, a sign that something is seriously amiss in the case for climate change.

A study I have just had published in the journal Climatic Change suggests however that this way of interpreting extreme cold is actually quite rare. At the same time, I found that people’s reading of the weather was strongly influenced by their pre-existing attitudes towards climate change.

The research was carried out in the middle of February 2011, when much of the UK was still experiencing severe disruption from ice and snow. Using a representative sample from across the country, I gauged the prevalence of two competing interpretations: either that the cold weather was seen by people as a form of counter-evidence for climate change, or as pointing to the reality of its existence.

Around one in seven people did agree that the cold winter of late 2010 "suggests climate change may not be happening." But three times as many – close to 40% of the respondents – were of the opposing view that this same winter "suggests climate change may now be a reality." The implication here is that climate change is now associated more with the idea of weather systems which are disrupted or strange, than with an expectation of uniformly higher temperatures.

A closer look at who held each of these types of view says a lot about the ways we bring our preconceptions to bear when forming opinions on this subject.

The extent to which people were already sceptical about the evidence base, human causation and impacts of climate change made a major difference to the meaning they placed on the weather. Sceptics tended to agree the winter constituted evidence against climate change, but the study’s results show that non-sceptics were at least as willing to accept the alternative position.

In a further sign of the political polarisation which has come to characterise climate change, people’s underlying worldviews – about seemingly unrelated topics such as discrimination against minorities or the distribution of wealth – in turn predicted the judgements they made about the cold weather.

Whether such events as the European freeze of 2010/2011 or the North American polar vortex actually have anything to do with climate change is an important question, and a subject of active scientific research. It has been proposed there may be a connection between a warming Arctic and continental freezing spells, but this is still a matter of some debate.

In a similar vein, it is hugely difficult to draw a straight line from climate change to specific weather events such as the storms and floods that have recently hit the UK. As Tyndall Centre Director Corinne Le Quéré points out, however, there is now a substantial evidence base that shows the weather has changed in the UK over the past half-century and that this is connected to a warming planet, though it remains hard to detect the exact contribution of climate change at the time extreme weather actually occurs.

Notwithstanding the careful distinctions made by scientists between weather and climate – as well as by well-informed comedians – a wider body of research continues to establish links between people’s encounters with the weather and their perceptions of climate change. The findings of another recent study published in Nature Climate Change suggest this effect can be so influential yet subtle that even performing word-sorting tasks in which temperature-related terms are hidden can lead people to change their beliefs and level of concern about climate change.

Perhaps the most important lesson to take from these studies, as with much psychological research, is that we are often more susceptible to our own biases and unconscious assumptions than we might realise. At least if we acknowledge this, then where climate change is concerned we may stand a better chance of leaving the real work of detection and explanation of changed conditions to those best qualified to achieve this.

• Stuart Capstick is a research associate in the School of Psychology at Cardiff University who specialises in public understanding of climate change.











