New research studies show droughts are becoming severe due to global warming and it all started around the beginning of the 20th century.
The findings emerged after century-old data collected from tree rings around the globe were analyzed by researchers from NASA, Columbia University and the Lawrence Livermore National Laboratory. The tree rings do not only signify the number of years that tree has been alive, they also reflect the climate conditions of the area in which the tree has lived. The trees grow significantly different when it is subjected to extended dry periods.
Several models have been made suggesting that rising temperatures have been influencing droughts from all over the world for over a century, and the results of this study confirm that.
"I was surprised to see the results, but perhaps I shouldn't have been," said Kate Marvel, a NASA climate scientists who led the study.
The amount of accumulating greenhouse gases in the atmosphere has grown significantly over the last century. Global droughts are one of the more visible marks of climate change's striking effects on the Earth. Nonetheless, she added, "the tree rings as well as the observations made are practically in agreement with what the models have been saying all this time."
In addition, the study also highlights some of the most complicated ideas around the concept of air pollution, as well as how pollution contributes to global warming. However, the study reveals that sometime around the 1950s, the effect of these air pollutants, from human activities, have started to decline. The researchers have reason to believe that this decline may be caused by the presence of aerosols in the atmosphere mainly from industrial activities.
There are particular types of pollutants that work to block the sun's rays from entering the Earth's atmosphere, essentially producing a cooling effect. As a result, several studies are also looking at the possibility that air pollutants may somehow be helping mask the effects of global warming.
A paper published in the journal, Geophysical Research Letters, suggests that eliminating the aerosols in the air could only result to an even warmer atmosphere. But there could be other explanations to this phenomena concerning global warming and life on Earth. Still, scientists believe that climate change has a strong influence on the droughts around the world as the temperatures in the atmosphere continue to rise.
"The temperatures in the last few years may only grow stronger in the next few decades," the research writes.
