The topic of global warming often brings to mind images of sweltering heat and rising sea levels, but recent research has suggested that it could lead to some unusual effects in certain areas – including making them colder. Despite being counterintuitive, this paradoxical outcome could be caused by the disruption of large-scale air currents and other changes in weather patterns. This leads to questions about the potential impact of global warming in different parts of the world, and why it might make some places colder.
One of the most likely causes of this phenomenon is the disruption of the Arctic circulation – the atmospheric currents which traditionally move warm air from the Atlantic to Northern Europe and Arctic regions. As the effects of global warming gradually accumulate, Arctic ice sheets are melting, affecting air temperatures and altering the Arctic circulation. This can push colder air southwards, resulting in a cooler climate in what were previously temperate areas. This was demonstrated by an extreme event in February 2018, when unusually cold air permeated the UK and much of Western Europe radically reducing temperatures – an event which has been linked to the decrease of Arctic sea ice.
Global warming can also lead to colder temperatures in certain areas indirectly, by disrupting larger weather patterns. Recently, the polar jet stream has been showing more signs of instability. This current – which typically moves stratus clouds, hurricanes and rain – separates tropical and polar air masses, which can create quite variable weather. As global warming intensifies, fluctuations in the jet stream become more common, splitting the stream into multiple branches or slowing it altogether. This leads to changes in how the humid, warm air from the midlatitudes would normally spread and develop – sometimes eliminating warmer weather systems altogether.
The direct and indirect effects of global warming can mean that environments which were previously warm become cooler. The reduced glacier cover, increased sea ice and other activities associated with melting can lead to the development of thick clouds. These clouds can then block out the sun’s rays, cooling temperatures even further. For example, reductions in sea ice in Svalbard have been linked to extreme snowfall and low temperatures.
Climate change can also lead to cooler temperatures as a result of higher elevations. Since warm air tends to rise, mountains near the coast can become colder due to rising air temperatures. This is due to the lack of warm air moving over the higher elevations, causing frost and snow. For instance, high elevations in California show an increase in snow years due to global warming, a consequence of warmer temperatures rising away from the low lands and low coastal areas.
Global warming is having a range of unexpected impacts around the world and effects on certain areas can be difficult to predict. While it might seem counterintuitive, evidence suggests that climate change can make some regions cooler. This ultimately highlights the need for continued awareness and research into the potential ramifications of climate change on our planet.
