1991 Mt. Pinatubo volcanic eruption behind depressing global sea levels for two decades
Scientists were baffled as earth’s mean sea level has been rising at a steady 3 millimeters per year since 1992. Now, after more than two decades they have been able to solve the mystery, which is the Mt. Pinatubo volcanic eruption of 1991.
The eruption considered to be the largest one of the late 20th century according to the researchers have cooled the oceans to suppress global sea level. Study’s lead researcher John Fasullo of the National Center for Atmospheric Research said that when they used climate models designed to remove the effect of the Pinatubo eruption, they were able to see the rate of sea level increasing.
On June 15, 1991, Mt. Pinatubo ejected 10 billion tons of magma. After a few months, NASA and space agency CNES have launched the first satellite altimeter, TOPEX/Poseidon to keep a tab on sea level from orbit. Many studies on sea level trends are based on the data from the satellite.
Dr. Fasullo and colleagues consider that the original data was distorted. In the eruption, a huge mass of aerosols were ejected that blocked sunlight and cooled the oceans for the time being. This resulted into a drop in the sea level by around six millimeters.
“Now that the impacts of Pinatubo have faded, this acceleration should become evident in the satellite measurements in the coming decade barring another major volcanic eruption”, affirmed Fasullo.
For now, there is no exact clarity on the level of how fast acceleration is taking place when it comes to and where sea levels are rising. But the researchers have confirmed that accelerated sea levels are real and ongoing, a topic that cannot be doubted.