China News Service, Beijing, March 1 (Reporter Sun Zifa) The Hongaha Apay Island submarine volcano in Tonga, a South Pacific island country, erupted violently in mid-January 2022. Whether this will have a significant impact on the global climate has aroused widespread concern.

　　A newly completed study by a team of Chinese scientists estimated the climate impact of Tonga's volcanic eruption from a historical perspective.

　　This study estimated the climate impact of volcanic eruptions in Tonga from the perspective of analogous large-scale volcanic eruptions in history, by the team of researcher Zhou Tianjun from the State Key Laboratory of Atmospheric Science and Geohydrodynamics Numerical Simulation (LASG), Institute of Atmospheric Physics, Chinese Academy of Sciences (Institute of Atmospheric Physics, Chinese Academy of Sciences). It was jointly completed with the team of Professor Liu Jian from Nanjing Normal University, Professor Liu Fei from Sun Yat-Sen University and Associate Professor Gao Chaochao from Zhejiang University. The paper was published on March 1 in the professional academic journal Advances in Atmospheric Science (AAS).

　　Zhou Tianjun, the corresponding author of the paper, emphasized: "Our estimation results show that the current eruption of the Tonga volcano is not enough to have a significant impact on the global climate, let alone the trend of global warming."

　　He said that satellite detection showed that the Tonga volcanic ash reached a height of 30 kilometers this time, and the total mass of sulfur dioxide injected into the stratosphere was about 400,000 tons, making it one of the largest volcanic eruptions since Mount Pinatubo in 1991.

　　In this study, the collaborative team first systematically summarizes the current scientific understanding of the impact of historical volcanic eruptions on the global climate in the climatology community. El Niño-type SST anomalies in the tropical Pacific and winter warming in Eurasia.

On the basis of understanding the impact of past volcanic eruptions on climate, they used climate simulation experiment data from the past millennium based on climate system models and found that there is a significant quasi-linear relationship between the magnitude of surface cooling in the following year after a volcanic eruption and the intensity of the volcano , and the model can better reproduce the cooling amplitude and spatial distribution after the observed volcanic eruption.

　　The collaborative team then further calculated the impact of the historical large-scale southern hemisphere volcanic eruptions on the surface temperature in the climate simulation to the intensity of the Tonga volcanic eruption through a scaling factor. It was estimated that the global average surface temperature dropped by only 0.004°C in the following year after the Tonga volcanic eruption. , which is within the scope of the internal variability of the climate system.

Among them, the cooling in parts of Australia and South America exceeded 0.01°C, and the cooling in most parts of China was within 0.01°C.

　　Dr. Zuo Meng, the first author of the paper and the Institute of Atmospheric Sciences, Chinese Academy of Sciences, said that from the history of nearly a thousand years, the climate impact of a single volcanic eruption is generally limited to 1-2 years.

However, if the frequency of volcanic eruptions increases or decreases in a certain period of time, it is enough to cause climatic anomalies in this period, such as the Medieval Warm Period (900-1300 AD) and the Little Ice Age (1550-1850 AD). It is generally believed that the former is due to the lower frequency of volcanic eruptions, while the latter is due to the higher frequency of volcanic eruptions. In addition, changes in solar irradiance also have an impact.

"Historically, the eruption of the volcano will have a certain continuity in time. How big is the final climate impact of the Tonga volcano this time, we also need to closely monitor its future activity situation."

　　Zhou Tianjun added that from a statistical point of view, a volcanic eruption is a small probability event, but if the intensity of a volcanic eruption reaches a certain level, it will have a larger climate impact. From the perspective of emergency management of disaster reduction, there are usually prepared plans internationally.

　　He believes that China's scientific research team engaged in the impact of volcanic climate, the Institute of Atmospheric Sciences of the Chinese Academy of Sciences, Nanjing Normal University and Sun Yat-sen University specialize in climate model development, simulation and prediction, and Zhejiang University specializes in the simulation and reconstruction of volcanic aerosols. "Volcanic climate impact emergency prediction system" as the goal, from the perspective of technical maturity, it is already highly feasible.

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