Stories of extended droughts and heat waves have repeatedly been making news headlines. According to scientists, these climatic weather fluctuations are occurring much more frequently, further shedding light on the potentially devastating effects of climate change. To make matters even worse, a study, published Monday in the Proceedings of the National Academy of Sciences, now reports that these extremes are also more likely to occur together.
Droughts and Heat Waves: The Troublesome Duo
As USA Today reports, the threat to the environment is far more significant when droughts and heat waves occur simultaneously. Furthermore, the more intense a heat wave is – in regards to duration and temperature – the greater the likelihood that it happened at the same time as a drought.
Amir AghaKouchak, an environmental engineer and the lead author of the study states, “Heat waves can kill people and crops while worsening air quality, and droughts exacerbate those serious impacts.”
To reach this conclusion, researchers examined heat and drought conditions in the United States from 1960 to 1980 and compared them with data from 1990 to 2010. For the purposes of this study, “drought,” according to LA Times, was defined as a period of time when the probability of precipitation was roughly 80% below the median level. A “heat wave,” on the other hand, was defined as “three consecutive days of temperatures that were in the top 15% for the ‘warm season’ [May through October].”
Based on these factors, scientists were able to determine that the simultaneous occurrence of a drought and heat wave was much more likely to occur in recent decades versus in earlier decades – especially in the South, Southwest and parts of the West, according to LA Times. Conversely, the two climate events were least likely to occur at the same time in parts of the Midwest and in Northern states.
The study draws more attention to the changing nature of our planet, which has undergone quite a few climatic and ecological deviations over the last past few years. Melting glaciers, rising sea levels and now, the confluence of droughts and heat waves are all indicative of that. In light of such changes, AghaKouchak warns everyone that heat waves are more likely to occur simply because of the rise in global temperatures. 2014, for example, was the hottest year on record. Even more frightening is that fact that 2015 is likely to break that record.
