Source: Xinhua Net
Washington, January 20 (Xinhua) -- Nasa said on January 19 that after analyzing satellite observation data, scientists at the agency believe that the recent volcanic eruption on Aha Apai Island in Tongahun will not have much impact on the global climate, and the amount of sulfur dioxide gas injected into the atmosphere by volcanic eruptions is far from reaching the threshold of impact on the climate.
NASA issued a communiqué on the 19th that a number of Earth observation satellites collected data during and after the eruption of the Hong Aha Apai Island volcano, and the agency's disaster program scientists are summarizing and analyzing the relevant images and data.
Satellite images taken on the 15th show the enormous power of the volcanic eruption in Tonga. The communiqué quoted Michigan Technological University volcanologist Simon Kahn as saying that the maximum diameter of the umbrella cloud formed by the eruption is about 500 kilometers, which is close to the scale of the eruption of Mount Pinatubo in the Philippines, but "the involvement of seawater in the eruption of Mount Tonga may have increased its explosiveness compared to pure magma eruptions such as Mount Pinatubo".
Nasa's communiqué said that satellite observations from the 15th to the 16th also showed that the volcanic eruptant in Tonga rose to an altitude of 31 kilometers, and a small amount of volcanic ash and gases may have risen to an altitude of 39.7 kilometers above the ground, indicating that the eruption has entered the atmospheric stratosphere. Volcanic eruptions stay longer in the dry stratosphere and travel longer distances than the more moist troposphere, which is closer to the ground. If enough volcanic eruptions enter the stratosphere, it has the potential to have a cooling effect on the global climate.
But NASA scientists analyzed satellite observations and believed that the eruption of The Tonga volcano is not expected to have much impact on the global climate. Satellite observations estimate that a volcanic eruption in Tonga injects about 400,000 tons of sulfur dioxide into the upper atmosphere, while at least 5 million tons of sulfur dioxide generally enters the upper atmosphere to have an impact on the climate. Brian Thun, an atmospheric scientist at the University of Colorado, explains: "In terms of possible impact on climate, the Tonga eruption is no different from a dozen eruptions that have occurred in the last 20 years... This effect may be observed in very detailed data studies, but the impact is too small for the average person to feel. ”
The specific environmental impact of the volcanic eruption in Tonga has yet to be further assessed. Cornell University's team of scientists studying the impact of volcanic ash issued a statement on the 18th, saying that in addition to the direct damage caused by the volcanic ash layer and the tsunami to the infrastructure, the thick volcanic ash also caused great harm to human health and the environment, and the interaction between seawater and volcanic ash particles exacerbated these hazards. (Participating reporters: Tan Jingjing, Zhang Ying)