Nights Are Becoming Warmer Than Days Due to Global Warming, Finds New Study
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Global warming is affecting climate change, but did you know it’s affecting day temperatures differently than night conditions. Circadian rhythm does not have a uniform temperature by design. Day time, in the presence of direct sunlight, feels warmer compared to night-time, in the absence of the direct heat. However, a new study reveals that nights are actually getting warmer faster than days – a possible fatal thing for many species.
The study analysed global daily temperatures for a little over 30 years. It has data from poles and tropics and oceans, as well as cities and villages – small or large. Researchers at Exeter have concluded that the earth’s day and night heating pattern have an asymmetry, possibly due to the Earth’s tilted axis.
The records date back to 1983 and end around 2017. It is a cumbersome database of six-hourly surface temperatures, covering some of the warmest years in our recorded history.
In the outliers, the daytime heat is rising considerably compared to the barely changing night temperatures. In even rare circumstances, some areas suggest a significant cooling over the years. However, the big picture is concerning. The average annual temperature, for almost more than half of Earth’s land surface rose a quarter of a degree Celsius more than that of the day's.
The number may seem infinitesimal. But aggregate it over the last thirty, or the next thirty years, and the eventual rise can have a significantly negative impact on ecology and environment. In a press release, Daniel Cox, lead author of the study and Ecologist at the University of Exeter expressed his concerns for nocturnal animals. “Species that are only active at night or during the day will be particularly affected,” he said.
In an order to fully understand the results, the team collected data of other environmental forces at work – humidity, precipitation, vegetation growth, etc. The analysis revealed that something as inconsistent as cloud cover could explain the imbalanced heating.
When excessive heat traps moisture, it condenses into clouds. The clouds also reflect light of certain wavelengths, back into space or around the ground. This mechanism comes in handy during the daytime as they act as a shield between the sun’s full blast of light and earth’s surface. Whereas, at night, heat from the ground cannot permeate through the clouds easily and the surface ends up getting warmer.
Cox explains that a primary glance at the data suggests the climate is getting wetter at night, which will impact insects, plants, and even mammals. However, further research is needed to establish the full effects of this asymmetric heating more concretely.