Workday Heat

Everyone knows how the work week can take a toll on employees, but new research suggests the five-day slog may have even broader impacts - on climate.

After examining more than 40 years of temperature data taken from roughly 10,000 surface stations, researchers from the National Oceanic and Atmospheric Administration and from the University of Reading in the U.K. found that temperature differences between day and night appear to follow distinct five-days-on, two-days-off patterns.

The scientists checked the data for all possible natural influences such as the lunar cycle as well as random variations and found neither to be at play. The only factor that could be causing the fluctuations was the Monday-through-Friday grind, they concluded in a recently published report in the Proceedings of the National Academy of Sciences.

"There is nothing in nature that should cause these data to be different," said Piers M de F. Forster, a meteorologist based at the University of Reading, England, who co-authored the study with NOAA's Susan Solomon. "So whatever the cause we find has to be something that we're changing, ourselves."

The meteorologists propose the differences in average temperatures between Saturdays as opposed to Thursdays, for example, may stem from workweek-induced pollution. Forster explains that during the workweek more people commute and more factories are in operation. Both contribute to the amount of particle pollution in the air.

Particles can influence cloud cover, but the kind of particles released into the atmosphere can lead to different changes, says Forster.

Lighter particles provide a surface for cloud droplets to form. This leads to an increase in cloud cover, which, in turn, can lead to an increase in temperature since clouds have an insulating effect.

人们普遍了解工作日是如何影响上班族的，然而最新研究表明这五天的劳作对气候的影响更加显著。

英国国家海洋及大气管理局和英国国立瑞丁大学的研究员分析了约一万个地面气象站40多年来采集的气温数据。他们发现昼夜温差出现明显的五天大两天小的变化规律。

科学家们检查了所有可能造成这种变化的自然因素，例如月亮运行周期和随机的变化，结果发现二者都不起作用。他们在最近召开的全国科学院研讨会上发表的报告中总结说：唯一可能解释这种温差变化的就是人们从周一到周五的辛苦劳作。

英国国立瑞丁大学的气象学家皮尔斯·福雷斯特和国家海洋及大气管理局的苏姗·所罗门合作主持了这项研究。福雷斯特说：“自然界中没有什么能够造成这些数据差异，所以不管原因是什么，它一定与我们自己正在改变的某种东西有关。”

气象学家们提出平均气温的差异可能是工作日中产生的污染造成的，例如周六和周四相比，平均气温就有一定的差异。福雷斯特解释说在五天工作日中，乘车上下班的人多，进行生产的工厂也多，这都会增加空气中的微粒含量，对大气造成污染。

微粒会影响云量，但是释放到大气中的不同颗粒会造成不同的变化，福雷斯特说。

较轻的微粒能够提供云滴形成所需要的界面，这样会增加云量，进而导致气温的升高，因为云有保温的作用。