A recent study has revealed that the recent California droughts were partially caused by climate change. The study was published in the journal of the Proceedings of the National Academy of Sciences on March 2 and it examined the role played by temperature in the drought cycle of state of California over the last 120 years.
The warmest years in California’s recorded history were 2013 and 2014 and this year’s is the fourth consecutive year of drought. Scientists from Stanford University set out to discover what had been causing the California drought and found that, among other things, climate change is also to blame. Aside from temperature, the researchers also took into account human emissions of greenhouse gases.
It was discovered that climate change is increasing the number of warm and dry years, which is when the scientists found that the droughts taken place.
Noah Diffenbaugh, lead author of the study and an Associate Professor in the School of Earth Sciences and Senior Fellow in the Woods Institute for the Environment at Stanford University, said that low precipitation isn’t enough to cause a drought. The key, he said, is whether or not it happens during a warm or cool year. He continued:
We’ve seen the effects of record heat on snow and soil moisture this year in California, and we know from this new research that climate change is increasing the probability of those warm and dry conditions occurring together.
For the study, the team of scientists analyzed climate change simulations and historical records dating back to 1895. After careful inspection of the data, they found that the years that were both dry and warm were twice as likely to be drought years, when compared to dry, but cool years. They also found that during the mid and early 20th century, moisture and temperature seemed to fluctuate completely independent of one another.
Graduate student in Diffenbaugh’s Climate and Earth System Dynamics research group and also co-author of the study, Danielle Touma stated that when looking at the historical record, a doubling of the odds of a warm and dry year and also a doubling of the frequency of drought years.
She concluded that warm weather conditions reduce the rainfall and snowfall and increase snowmelt and water loss from plants and soils.
The researchers hope that the study results are going to help California state officials to better deal with any future droughts.
Image Source: Peak Water