Currently, there are about 1350 active volcanoes on the planet and at least 4 of them are in Spain. Anticipating an eruption, as much as possible, is vital to guarantee the safety of those who live around them, about 800 million people globally. Geological studies, seismic instruments, satellites and thermographic images were some of the tools, but now a more “simple” ally arrives: trees.
According to NASA, experts can Determine if a volcano is about to erupt by the greenery of the surrounding trees: The leaves with a more intense color indicate a possible imminent eruption. Until now, these subtle color changes could only be observed from the surface, but recently they have discovered a way to monitor them from space.
The collaboration between NASA and the Smithsonian Institute could revolutionize the detection of the first signs of a volcanic eruption. These signals can help protect communities from the worst effects of volcanic explosionssuch as lava flows, expelled rocks, ash falls, mud landslides and toxic gas clouds.
“There are early volcano alert systems -explains Florian Schwandner, volcanologist and head of the Division of Earth Sciences of the NASA AMES Research Center in California -. The objective is to improve them and act more in advance”
The current indicators of an imminent volcanic eruption include seismic activity, Changes in the height of the land and sulfur dioxide emissions, visible from space. Scientists also look for carbon dioxide emissions (CO₂) associated with magma near the earth’s surface, but these are more difficult to detect precisely by satellites.
With this in mind, scientists have developed methods to monitor carbon dioxide based on the color of trees around volcanoes. Co₂ clouds emanating from volcanoes about to erupt improve the health of surrounding trees and plants, making its leaves more green and leafy. In a nutshell: they give them more “food.”
Until recently, scientists had to move to volcanoes to measure their CO₂ levels. By using the color of the tree leaves as an indicator of volcanic gase concentrations, this step is possible.
“There are numerous satellites that we can use to perform this type of analysis – adds Nicole Guinn, main author of the study -. However, measuring the greenery of the trees from space will not be useful in all volcanic environments. Many volcanoes do not house trees, or at least there are not enough to measure them with satellites. Some trees and forests can react unexpectedly to changes in carbon dioxide levels, for example, if they have been affected by abnormal fires, diseases or weather conditions. Tracking the effects of volcanic carbon dioxide on trees will not be a miraculous solution. But it is something that could change the rules of the game. ”
To expand the potential of the new method, NASA researchers, the Smithsonian Institute and other organizations recently launched the Unified Air Validation Experiment: Tierra-Oceano (Avuelo)that will compare satellite images of trees around volcanoes with land observations. The objective is to ensure that the data coincides, so that scientists can calibrate space instruments and advance research.