Key points of the report
At 12:27 Beijing time on January 15, a violent Pliny type volcanic eruption occurred near the South The Pacific Securities Co.Ltd(601099) island country Tonga Hong aha ApaI island. The ash and gas ejected by major volcanic eruptions enter the upper atmosphere, which usually leads to the reduction of the earth’s average temperature and abnormal precipitation in some areas. The growth of crops is closely related to temperature and precipitation. Extreme weather may reduce production and reduce the excellent rate. Combined with the existing literature on historical volcanic activities, this paper analyzes the impact of Tonga volcanic eruption on global climate and crops.
At 12:27 Beijing time on January 15, a violent Pliny type volcanic eruption occurred near the South The Pacific Securities Co.Ltd(601099) island country Tonga Hong aha ApaI island. As of January 16, 2022, the volcanic eruption activity is still continuing. According to the observation of weathermodels website and other parties, this volcanic eruption may be listed as one of the strong volcanic eruptions in recent 30 years (VEI > 5).
This paper analyzes the possible impact of Tonga volcanic eruption from the perspectives of climate and agriculture by combing the research on world volcanic activity and its climate color in relevant documents such as Li Jing (2005).
First of all, in terms of temperature, the volcanic ash and gas ejected by major volcanic eruptions enter the upper atmosphere, and the sulfur-containing compounds rise to the stable stratosphere and convert into sulfuric acid aerosols, weakening the solar radiation entering the troposphere. Therefore, volcanic activities usually reduce the average air flow of the earth. Secondly, in terms of precipitation, the volcanic ash and sulfur dioxide gas produced by volcanic eruption increase the hygroscopic condensation nodules in the atmosphere and catalyze the occurrence and strengthening of precipitation. The large water vapor produced by volcanic eruption is conducive to the supersaturation of water vapor in local areas. Therefore, volcanic activity is often accompanied by precipitation anomalies in local areas.
Finally, in agriculture, climate change affects the growth and yield of crops. From the consequences of historical volcanic eruption, Tambora volcano erupted to vei-7 in 1815, and the decline of temperature led to large-scale crop failure in Europe, North America and Asia in the northern hemisphere; In 1883, the eruption of Krakatoa volcano reached vei-6, and the decline of temperature led to the damage of crop production all over Britain; In 1991, the eruption of Pinatubo volcano developed, and the vei-6 level stabilized and decreased, resulting in a continuous decline in the production of beans, buckwheat and fruits in the United States. Therefore, the abnormal climate such as the decline of gas flow caused by volcanic activity may reduce crop yield.
From the perspective of this Tonga volcanic eruption, the eruption site is in the southern hemisphere and has relatively little impact on the northern hemisphere. The climate of southern Australia, southern Brazil, New Zealand, Argentina, Chile and South Africa in the middle and high latitudes of the southern hemisphere will be affected first. Moreover, since the volcanic eruption point is near the ENSO monitoring area, we need to be vigilant about the impact of volcanic eruption on wind and ocean currents. If the volcanic eruption lasts for a long time, it may lead to too much aerosol entering the stratosphere and increase the probability of extreme weather.
