An undersea volcano at Hunga Tonga-Hunga Ha'apai(HTHH)near the South Pacific island nation of Tonga,erupted violently on 15 January 2022.Potential climate impact of the HTHH volcanic eruption is of great concern t...An undersea volcano at Hunga Tonga-Hunga Ha'apai(HTHH)near the South Pacific island nation of Tonga,erupted violently on 15 January 2022.Potential climate impact of the HTHH volcanic eruption is of great concern to the public;here,we intend to size up the impact of the HTHH eruption from a historical perspective.The influence of historical volcanic eruptions on the global climate are firstly reviewed,which are thought to have contributed to decreased surface temperature,increased stratospheric temperature,suppressed global water cycle,weakened monsoon circulation and El Niño-like sea surface temperature.Our understanding of the impacts of past volcanic eruptions on global-scale climate provides potential implication to evaluate the impact of the HTHH eruption.Based on historical simulations,we estimate that the current HTHH eruption with an intensity of 0.4 Tg SO_(2)injection will decrease the global mean surface temperature by only 0.004℃in the first year after eruption,which is within the amplitude of internal variability at the interannual time scale and thus not strong enough to have significant impacts on the global climate.展开更多
A 600-year integration performed with the Bergen Climate Model and National Centers for Environmental Prediction/National Center for Atmospheric Research （NCEP/NCAR） reanalysis data were used to investigate the impa...A 600-year integration performed with the Bergen Climate Model and National Centers for Environmental Prediction/National Center for Atmospheric Research （NCEP/NCAR） reanalysis data were used to investigate the impact of strong tropical volcanic eruptions on the East Asian summer monsoon （EASM） and EASM rainfall.Both the simulation and NCEP/NCAR reanalysis data show a weakening of the EASM in strong eruption years.The model simulation suggests that North and South China experience droughts and the Yangtze-Huaihe River Valley experiences floods during eruption years.In response to strong tropical volcanic eruptions,the meridional air temperature gradient in the upper troposphere is enhanced,which leads to a southward shift and an increase of the East Asian subtropical westerly jet stream （EASWJ）.At the same time,the land-sea thermal contrast between the Asian land mass and Northwest Pacific Ocean is weakened.The southward shift and increase of the EASWJ and reduction of the land-sea thermal contrast all contribute to a weakening of the EASM and EASM rainfall anomaly.展开更多
Using the dataset provided by the Smithsonian Institution＇s Global Volcanism Program, we have extracted the large volcanic eruptions（volcanic explosivity index ≥ 4） from the period 1750–2010 and have then analyze...Using the dataset provided by the Smithsonian Institution＇s Global Volcanism Program, we have extracted the large volcanic eruptions（volcanic explosivity index ≥ 4） from the period 1750–2010 and have then analyzed the main characteristics of large volcanic eruptions since 1750 according to their geographic latitudes, their elevations, and the years and months in which they occurred. The results show that most large volcanic eruptions were located around the margins of the Pacific Ocean and the islands of Sumatra and Java, especially in the equatorial regions（10°N–10°S）. Large volcanic eruptions were concentrated at 1000–2000 m elevations and in the months of January and April. There were more eruptions in the summer half-year（from April to September） than in the winter half-year（from October to the next March）. Large volcanic eruptions have interdecadal fluctuations, including cycles of 15–25 years and 35–50 years, which were detected by Morlet wavelet analysis, with the fluctuations being more frequent after 1870 than before. During the periods 1750–1760, 1776–1795, 1811–1830, 1871–1890, 1911–1920 and 1981–1995, there were relatively many large volcanic eruptions.展开更多
A large number of seismic records are discovered for the first time in the historical materials about Wudalianchi volcanic group eruption in 1720~1721, which provides us with abundant volcanic earthquake information. ...A large number of seismic records are discovered for the first time in the historical materials about Wudalianchi volcanic group eruption in 1720~1721, which provides us with abundant volcanic earthquake information. Based on the written records, the relationship between earthquake and volcanic eruption is discussed in the paper. Fur-thermore it is pointed that earthquake swarm is an important indication of volcanic eruption. Therefore, monitoring volcanic earthquakes is of great significance for forecasting volcanic eruption.展开更多
In this study, we presented new theory of effusive and explosive of volcanic eruptions. New explanation of eruption mechanisms was done by using the Elemental Buoyancy Theory and new K-Th-U structure of Earth, develop...In this study, we presented new theory of effusive and explosive of volcanic eruptions. New explanation of eruption mechanisms was done by using the Elemental Buoyancy Theory and new K-Th-U structure of Earth, developed early by author. During investigation of effusive eruptions, it was given clear answer on the question why the light chemical elements, mainly silicon and sulfur compound, currently dominate in the volcanic ashes, gases, and in the magma lavas. At investigation of explosive mechanism, we analyzed 38 strong eruptions with Volcanic Explosivity Index (VEI) more than 4+. It was shown that there is a link between the planet configurations and volcanic eruptions. It can be found that volcano eruptions occurred at the different types of planet alignments. The phenomenon does depend neither on planet mass nor on the relative positions of planets. Also the phenomenon does not depend on the distance between planets, but often eruptions were observed when the distances between planets are multiple units. Also in work, it was demonstrated that the planet alignment affects not only natural processes on the Earth, but also impact the Sun activity. Based on the comparison phenomenon on the Earth and Sun, we get new mechanism to rapidly rising up pressure under the lithospheric planes by gravity vortexes. This gravity vortex was called as terrestrial magmatic protuberances.展开更多
ENSO is an interannual mode which may be affected by external forcing, such as volcanic eruptions. Based on the reconstructed volcanic eruptions chronology and ENSO sequences, both 195 large volcanic eruptions (VEI≥4...ENSO is an interannual mode which may be affected by external forcing, such as volcanic eruptions. Based on the reconstructed volcanic eruptions chronology and ENSO sequences, both 195 large volcanic eruptions (VEI≥4) and 398 ENSO (El Niño and La Niña) events were extracted from 1525 to 2000. An analysis of the correspondence between the large volcanic eruptions and ENSO events was performed by matching the large volcanic eruptions with the types and magnitudes of ENSO events present in the 0-2 years after the eruptions. The results show the following: (1) The percentages of ENSO events within the 3 years after the large eruptions had increased to 68.3% from 31.7% compared with those with no-eruptions in the previous 0-2 years. In addition, the ratio of El Niño to La Niña events turned from 2:3 to 1:1, and more El Niño events occurred in the 0 year after eruptions in the low-latitudes of the Northern Hemisphere and in the tropics but more La Niña events occurred in the 0 year after in the high-latitudes of the Northern Hemisphere and the Southern Hemisphere. (2) After the eruptions, the weak (W) El Niño events had increased by 8 percentage points and the very strong (VS) El Niño events had decreased by 10 percentage points; conversely, there was a decrease by 15 percentage points of the weak La Niña events and an increase by 11.4 percentage points of the very strong La Niña events. Specifically, the percentages of strong La Niña events increased to a peak at 1 (+1) year after the eruptions. (3) The percentage of eruptions followed by single-year ENSO was the greatest. The percentage of ENSO events that occurred in the consecutive 2 years following an eruption was approximately equal to the percentage of events that occurred consecutively 3 years following an eruption, and both sets of ENSO magnitudes showed a decreasing trend.展开更多
Based on data in the last 500 years for strong volwtc aedvity and the sununer drought/flood types available in China, the statistical relatons 0f the volcanic eruptions in seasons and several ropons and the drowtood t...Based on data in the last 500 years for strong volwtc aedvity and the sununer drought/flood types available in China, the statistical relatons 0f the volcanic eruptions in seasons and several ropons and the drowtood types and grade index of main wions in China have ban inveStigned. The possible teleconnection bforan flood in the Yangtze hiver and the Huaihe foveL Valleys in 1991 and the volcanic eruption of Mt. Pinatubo in June of 1991 has bam also exathened. It is found that ehas of volcanic eruption in differen ropons in the worid vary on droguood in diffend edons of China, but in some cases the the is absolutely opposite in respect of the summer drowood. Statshcal test shows that in terms of stud confidence levels of the reation for dividing the volcanic eruptions as several ropons are higher than that for volcanic eruPhon in the worid as Whole.展开更多
Near-surface wind speed(NSWS),a determinant of wind energy,is influenced by both natural and anthropogenic factors.However,the specific impacts of volcanic eruptions on NSWS,remain unexplored.Our simulations spanning ...Near-surface wind speed(NSWS),a determinant of wind energy,is influenced by both natural and anthropogenic factors.However,the specific impacts of volcanic eruptions on NSWS,remain unexplored.Our simulations spanning the last millennium reveal a consistent 2-year global NSWS reduction following 10 major historical eruptions.This equates to an NSWS decrease of approximately two inter-annual standard deviations from AD 851 to 1849.This reduction is linked to the weakening of subtropical descending air and a decrease in downward momentum flux,triggered by volcanic aerosol forcing.The 1815 Tambora eruption,one of the most powerful in recent history,led to a~9.2%reduction in global wind power density in the subsequent 2 years.Our research fills a knowledge gap,establishes a theoretical foundation for empirical studies,and highlights the potential wind energy risks linked to large atmospheric aerosol injections,including volcanic eruptions,nuclear warfare,and climate intervention.展开更多
The Asia-Pacific Region Global Earthquake and Volcanic Eruption Risk Management(G-EVER)Consortium among the Asia-Pacific geohazard research institutes was established in 2012 with the main objective of reducing the ri...The Asia-Pacific Region Global Earthquake and Volcanic Eruption Risk Management(G-EVER)Consortium among the Asia-Pacific geohazard research institutes was established in 2012 with the main objective of reducing the risk caused by earthquakes,tsunamis and volcanic eruptions worldwide.The first G-EVER workshop was held in Tsukuba,Japan in February 2012.The G-EVER1 accord was approved by the workshop participants which made 10 recommendations that focused on the enhancement of collaboration,sharing of resources and making information about the risks of earthquakes and volcanic eruptions freely available and understandable.展开更多
The Cenozoic volcanostratigraphy in the Changbaishan area had complex building processes.Twenty-two eruption periods have been determined from the Wangtian＇e, Touxi, and Changbaishan volcanoes. The complex volcanostr...The Cenozoic volcanostratigraphy in the Changbaishan area had complex building processes.Twenty-two eruption periods have been determined from the Wangtian＇e, Touxi, and Changbaishan volcanoes. The complex volcanostratigraphy of the Changbaishan area can be divided into four types of filling patterns from bottom to top. They are lava flows filling in valleys（LFFV）, lava flows filling in platform（LFFP）, lava flows formed the cone（LFFC）, and pyroclastic Flow filling in crater or valleys（PFFC/V）. LFFV has been divided into four layers and terminates as a lateral overlap. The topography of LFFV, which is controlled by the landform, is lens shaped with a wide flat top and narrow bottom.LFFP has been divided into three layers and terminates as a lateral downlap. The topography of LFFP is sheet and tabular shaped with a narrow top and wide bottom. It has large width to thickness ratio. It was built by multiple eruptive centers distributed along the fissure. The topography of LFFC, which is located above the LFFP, has a hummocky shape with a narrow sloping top and a wide flat bottom. It terminates as a later downlap or backstepping. It has large width to thickness ratio. It was built by a single eruptive center. The topography of PFFC/V, which located above the LFFC, LFFP, or valley, has the shape of fan and terminates as a lateral downlap or overlap. It has a small width to thickness ratio and was built by a single eruptive center. The filling pattern is controlled by temperature, SiO_2 content,volatile content, magma volume, and the paleolandform. In the short term, the eruptive production of the Changbaishan area is comenditic ash or pumice of a Plinian type eruption. The eruptive volume in future should be smaller than that of the Baguamiao period, and the filling pattern should be PFFC/V,which may cause huge damage to adjacent areas.展开更多
Major volcanic eruptions(MVEs)have attracted increasing attention from the scientific community.Previous studies have explored the climatic impact of MVEs over the past two millennia.However,proxy-based reconstruction...Major volcanic eruptions(MVEs)have attracted increasing attention from the scientific community.Previous studies have explored the climatic impact of MVEs over the past two millennia.However,proxy-based reconstructions and climate model simulations indicate divergent responses of global and China’s regional climates to MVEs.Here,we used multiple data from observations,reconstructions,simulations,and assimilations to summarize the historical facts of MVEs,the characteristics and mechanisms of their climatic impact,and directions for future research.We reviewed volcanic datasets and determined intensive MVE periods;these periods corresponded to the years 530–700,1200‒1460,and 1600‒1840 CE.After tropical MVEs,a substantial cooling effect is observed throughout the globe and China on the interannual-interdecadal time scales but an inconsistent cooling magnitude is detected between reconstructions and simulations.In the first summer after tropical MVEs,a decrease in global and monsoonal precipitation is observed.In reconstructions and simulations,an increased precipitation is seen for the Yangtze River Basin,while large uncertainties in precipitation changes are present for other regions of China.Decadal drought can be induced by frequent eruptions and volcanism superimposed on low solar irradiation and internal variability.MVEs affect climate directly through the radiative effect and indirectly by modulating internal variability,such as the El Niño‒Southern Oscillation(ENSO)and Atlantic Multidecadal Oscillation(AMO).However,changes in the phase,amplitude,and periodicity of ENSO and AMO after MVEs and the associated mechanisms remain controversial,which could account for model-reconstruction disagreements.Moreover,other internal variability,uncertainties in reconstruction methods and aerosol‒climate models,and climate background may also induce model-reconstruction disagreements.Knowledge gaps and directions for future research are also discussed.展开更多
This study investigates the influences of strong tropical volcanic eruptions(SVEs) on daily temperature and precipitation extreme events using long-term simulations from the Hadley Centre Coupled Model version 3(HadCM...This study investigates the influences of strong tropical volcanic eruptions(SVEs) on daily temperature and precipitation extreme events using long-term simulations from the Hadley Centre Coupled Model version 3(HadCM3) and the Community Earth System Model version 1.1(CESM1). The results indicate that the occurrences of daily hot extremes and daily heavy precipitation extremes decrease over most parts of the world in the peak forcing years of SVEs. Due to the volcanic cooling effect, the average probability of daily hot extremes decreases by approximately 50% across the globe. The decrease in intensity is stronger for midlatitude land regions and tropical South America.In contrast, daily cold extremes occur more frequently over most parts of continental regions. Globally, a cold extreme event expected once every 3 years under non-volcanic conditions can be expected every 1.5 years on average in the peak forcing years. Overall, the SVE-induced cooling effect plays a dominant role in regulating daily cold and hot extremes. Over high-latitude Eurasian regions, in contrast to other continental regions, the probability and intensity of daily cold extremes decrease due to an SVE-strengthened polar vortex and the associated temperature advection anomalies. With regard to daily heavy precipitation extremes, the probability and intensity both decrease over most monsoon areas. Further analysis suggests that the reduced probability and intensity of daily heavy precipitation extremes are mainly due to the SVE-induced global decrease in the water-holding capacity.展开更多
This thesis lists and describes 6 pairs of tectonic events, i.e ., historical volcanic eruptions associated with historical strong earthquakes, based on the analysis for the records of historical volcanic eruptions...This thesis lists and describes 6 pairs of tectonic events, i.e ., historical volcanic eruptions associated with historical strong earthquakes, based on the analysis for the records of historical volcanic eruptions and historical strong earthquakes in China and its adjacent region since the first record. And discusses the relationship between historical eruptions and strong earthquakes by means of analyzing the characteristics of tectonic events themselves, plate movement, regional seismicity, and regional stress environment in China and its adjacent region.展开更多
Based on the historical data of the excessivc rains ovcr the middle-lower reaches of Changjiang River in two hundred and fifty years (1651--1900) and the data of 'Very Large' volcanic eruptions (VEI≥5) in the...Based on the historical data of the excessivc rains ovcr the middle-lower reaches of Changjiang River in two hundred and fifty years (1651--1900) and the data of 'Very Large' volcanic eruptions (VEI≥5) in the period of 1650--1900, which are selected from the table of volcanic eruption year complied by Sim- kin et al. (198l). This paper analyses the interannual variation of various kinds of continuous rains in the historical period, as well as the relation between plum-continuous rains and waterlogging along Chang- jiang-Huaihe reaches, and between 'Very Large' volcanic cruption and continuous rains over the middle- lower reaches of Changjiang Rivex.展开更多
When gigantic meteorite impact sites in Southern Africa are plotted on the geological map of the region,they overlap with the SW-NE fault lines and it indicates that meteorite impacts have contributed to the geologica...When gigantic meteorite impact sites in Southern Africa are plotted on the geological map of the region,they overlap with the SW-NE fault lines and it indicates that meteorite impacts have contributed to the geological structure of the region.The Morokweng Meteorite Impact of 145 Ma(Million years ago),at the J/K(Jurassic/Cretaceous)boundary,seems to have broken up the Gondwanaland.It is plausible that,at the time of continental break-up,seawater poured into Morokweng crater and ignited a gigantic volcanic eruption which delivered low viscose magma into the outer space to form the Moon.An extremely flat surface of the Megakalahari extending 3,800,000 sq.km at 800-1,200 m above sea level in the central and southern Africa seems to be the terrestrial residue of fluid magma at the end of the volcanic event.展开更多
The Longhai-Zhangpu coastal region lies in the so-called Golden Triangle area of southern Fujian Province. Tectonically, it is located on the southern segment of the Changle-Zhao＇an fault zone, being one of the regio...The Longhai-Zhangpu coastal region lies in the so-called Golden Triangle area of southern Fujian Province. Tectonically, it is located on the southern segment of the Changle-Zhao＇an fault zone, being one of the regions of Tertiary and Quaternary basaltic eruptions in China＇s southeast coastal area. In this area there are the Liuhui （Longhai County ）-Jiangjun＇ ao （Zhangpu County） and Gangwei （ Longhai County ）-Huxi （ Zhangpu County ） faults, along which basaltic eruption has occurred. The faults have been significantly active since the Quaternary, and several small to moderate earthquakes have occurred on the faults. In this paper, the basic characteristics of the late Quaternary activities and the combination relation of the faults are discussed on the basis of an analysis of along-fault basaltic eruptions during the late Tertiary to late Pleistocene, as well as the differential variation of geomorphic surfaces and marine deposits on both sides of the faults. The results show that the Liuhui-Jiangjun＇ao fault is a late Pleistocene active fault. During the late Tertiary to late Pleistocene, three stages of basaltic eruptions occurred along the fault, among which the first stage occurred in the Pleistocene to early Pleistocene, the second stage in the middle Pleistocene and the third stage in the late Pleistocene. The Gangewei-Huxi fault can also be considered a late Pleistocene active fault. The elevation rate of the downthrown side of the fault is estimated to be 1. 11mm/a.These two faults have dissected the area into the Gangwei graben, south Taiwushan horst and the graben in the sea area to the east of Liuhul-Jiangjun＇ao.展开更多
This study was conducted in order to examine the influence of long-term volcanic activity on vegetative succession and growth on the slope of Sakurajima in southern Kyushu, Japan. We investigated the vegetation,depth ...This study was conducted in order to examine the influence of long-term volcanic activity on vegetative succession and growth on the slope of Sakurajima in southern Kyushu, Japan. We investigated the vegetation,depth of the volcanic ash layer, and dry density and p H of the surface soil at six places on the north-northwestern slope, 2.3–3.4 km from the Minami-dake crater, where a layer of pumice stone was deposited by the Taisho eruption in 1914. The height and diameter at breast height（DBH） of the trees increased with increasing distance from the Minami-dake crater, as did the number of individuals and species, and basal area. The Shannon–Wiener diversity index（H＇） demonstrates that vegetative succession is significantly affected by distance from the Minami-dake crater, as areas farther from the crater exhibited later seral stages. Comparison of the diversity index and species number of the crater region with that of the climax forest in Kagoshima indicates that vegetative growth alone cannot advance succession in the study area, as the local vegetative community is heavily influenced by the harsh environmental conditions associated with continual exposure to long-term volcanic activity. Seral stage, ash layer depth,dry density, and p H of the soil surface layer are governed by distance from the Minami-dake crater. The results of this study indicate that conditions for vegetative growth and succession improve with increasing distance from the source of constant volcanic activity. Thus, soil development is promoted by the acidification of the soil, which decreases the dry density and p H of the soil surface layer.The introduction of plant species resistant to volcanic ash and gas is recommended to promote soil development and improve the infiltration capacity of the soil.展开更多
The black shales of Wufeng and Longmaxi Formation(Late Ordovician-Early Silurian period)in Sichuan Basin are the main strata for marine shale gas exploration,which have a yearly shale gas production of 228×10^(8)...The black shales of Wufeng and Longmaxi Formation(Late Ordovician-Early Silurian period)in Sichuan Basin are the main strata for marine shale gas exploration,which have a yearly shale gas production of 228×10^(8)m^(3)and cumulative shale gas production of 919×10^(8)m^(3).According to the lithological and biological features,filling sequences,sedimentary structures and lab analysis,the authors divided the Wufeng/Guanyinqiao and Longmaxi Formations into shore,tidal flat,shoal,shallow water shelf and deep water shelf facies,and confirmed that a shallow water deposition between the two sets of shales.Although both Formations contain similar shales,their formation mechanisms differ.During the deposition of Wufeng shale,influenced by the Caledonian Movement,the Central Sichuan and Guizhou Uplifts led to the transformation of the Sichuan Basin into a back-bulge basin.Coinstantaneous volcanic activity provided significant nutrients,contributing to the deposition of Wufeng Formation black shales.In contrast,during the deposition of Longmaxi shale,collisions caused basement subsidence,melting glaciers raised sea levels,and renewed volcanic activity provided additional nutrients,leading to Longmaxi Formation black shale accumulation.Considering the basic sedimentary geology and shale gas characteristics,areas such as Suijiang-Leibo-Daguan,Luzhou-Zigong,Weirong-Yongchuan,and Nanchuan-Dingshan are identified as key prospects for future shale gas exploration in the Wufeng-Longmaxi Formations.展开更多
Volcanic eruptions potentially threaten local and global environments,making it crucial to reconstruct their eruption history for risk assessments and forecasts.However,accurately dating of young(e.g.,Holocene)volcano...Volcanic eruptions potentially threaten local and global environments,making it crucial to reconstruct their eruption history for risk assessments and forecasts.However,accurately dating of young(e.g.,Holocene)volcanoes remains challenging.For example,K-Ar and^(40)Ar/^(39)Ar dating are potentially problematic due to the long half-lives of radioisotopes,while radiocarbon dating requires organic materials.The study used optically stimulated luminescence(OSL)dating on quartz to accurately constrain the ages of lava-baked sediments from the Tengchong volcanic field,southeastern margin of the Tibetan Plateau.The results show two types of quartz OSL characteristics in the initial OSL signals.The first type,dominated by the fast component,yields reliable OSL ages.In contrast,the second type,dominated by the medium component,shows a negative correlation between equivalent dose(D_(e))and recuperation,and a decreasing trend in D_(e)over illumination time,providing the underestimated ages due to the influence of the unstable medium component.These underestimated OSL ages are corrected using the D_(e)-recuperation plot.Combining with previous chronological studies,we conclude that Tengchong volcanoes have erupted at least seven times during the Holocene,occurring at 11.6–11.1,≤11.4–10.3,5.9–5.7,5.0–4.8,3.5–2.5,2.0 thousand years ago,and1609 AD.D_(e)spite the current stability of the Tengchong volcanoes,frequent tectonic activities,eruptive history,and the presence of active magma chambers suggest the potential for future volcanic eruptions.展开更多
The paper considers a catastrophic event-the eruption of Hunga Tonga-Hunga Ha’apai volcano on January 15,2022.The process of preparation and eruption of Hunga Tonga volcano generated tsunami waves that were observed ...The paper considers a catastrophic event-the eruption of Hunga Tonga-Hunga Ha’apai volcano on January 15,2022.The process of preparation and eruption of Hunga Tonga volcano generated tsunami waves that were observed throughout the World Ocean.This event was notable for its unprecedented global impact and the early appearance of tsunami waves at distant coastal stations.So,the first waves at tide gauge stations in Chile and Peru were recorded 4 hours earlier than the arrival time of tsunami waves to the tide gauge after the eruption of Tonga volcano.Two mechanisms are possible for the generation of early tsunami waves:acoustic Lamb waves generated by a volcanic explosion and submarine landslides that occurred on the slopes of the volcano during the preparatory phase of the eruption.In this study,numerical simulation of various pre-eruption landslide scenarios on the slope of Hunga Tonga volcano is carried out in an attempt to explain these early tsunami waves.Under computation the elastoplastic model of landslide was taken into account.Wave characteristics of a tsunami on the coast of Chile and Peru generated by a landslide process on a volcanic slope are obtained.A detailed comparison of virtual tide gauge data with observational ones is used to validate this model.The results obtained can be used to improve early warning systems.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.41988101,,42105047).
文摘An undersea volcano at Hunga Tonga-Hunga Ha'apai(HTHH)near the South Pacific island nation of Tonga,erupted violently on 15 January 2022.Potential climate impact of the HTHH volcanic eruption is of great concern to the public;here,we intend to size up the impact of the HTHH eruption from a historical perspective.The influence of historical volcanic eruptions on the global climate are firstly reviewed,which are thought to have contributed to decreased surface temperature,increased stratospheric temperature,suppressed global water cycle,weakened monsoon circulation and El Niño-like sea surface temperature.Our understanding of the impacts of past volcanic eruptions on global-scale climate provides potential implication to evaluate the impact of the HTHH eruption.Based on historical simulations,we estimate that the current HTHH eruption with an intensity of 0.4 Tg SO_(2)injection will decrease the global mean surface temperature by only 0.004℃in the first year after eruption,which is within the amplitude of internal variability at the interannual time scale and thus not strong enough to have significant impacts on the global climate.
基金supported by the Strategic Priority Research Program(Grant No.XDA05110203) of the Chinese Academy of Sciencesthe Research Council of Norway through the India-Clim projectthe National Basic Research Program of China(Grant Nos.2012CB955401 and 2010CB951802)
文摘A 600-year integration performed with the Bergen Climate Model and National Centers for Environmental Prediction/National Center for Atmospheric Research （NCEP/NCAR） reanalysis data were used to investigate the impact of strong tropical volcanic eruptions on the East Asian summer monsoon （EASM） and EASM rainfall.Both the simulation and NCEP/NCAR reanalysis data show a weakening of the EASM in strong eruption years.The model simulation suggests that North and South China experience droughts and the Yangtze-Huaihe River Valley experiences floods during eruption years.In response to strong tropical volcanic eruptions,the meridional air temperature gradient in the upper troposphere is enhanced,which leads to a southward shift and an increase of the East Asian subtropical westerly jet stream （EASWJ）.At the same time,the land-sea thermal contrast between the Asian land mass and Northwest Pacific Ocean is weakened.The southward shift and increase of the EASWJ and reduction of the land-sea thermal contrast all contribute to a weakening of the EASM and EASM rainfall anomaly.
基金National Natural Science Foundation of China,No.41430528 Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDA05080100+1 种基金 China Global Change Research Program,No.2010CB950100 Jiangsu Collaborative Innovation Center for Climate Change
文摘Using the dataset provided by the Smithsonian Institution＇s Global Volcanism Program, we have extracted the large volcanic eruptions（volcanic explosivity index ≥ 4） from the period 1750–2010 and have then analyzed the main characteristics of large volcanic eruptions since 1750 according to their geographic latitudes, their elevations, and the years and months in which they occurred. The results show that most large volcanic eruptions were located around the margins of the Pacific Ocean and the islands of Sumatra and Java, especially in the equatorial regions（10°N–10°S）. Large volcanic eruptions were concentrated at 1000–2000 m elevations and in the months of January and April. There were more eruptions in the summer half-year（from April to September） than in the winter half-year（from October to the next March）. Large volcanic eruptions have interdecadal fluctuations, including cycles of 15–25 years and 35–50 years, which were detected by Morlet wavelet analysis, with the fluctuations being more frequent after 1870 than before. During the periods 1750–1760, 1776–1795, 1811–1830, 1871–1890, 1911–1920 and 1981–1995, there were relatively many large volcanic eruptions.
文摘A large number of seismic records are discovered for the first time in the historical materials about Wudalianchi volcanic group eruption in 1720~1721, which provides us with abundant volcanic earthquake information. Based on the written records, the relationship between earthquake and volcanic eruption is discussed in the paper. Fur-thermore it is pointed that earthquake swarm is an important indication of volcanic eruption. Therefore, monitoring volcanic earthquakes is of great significance for forecasting volcanic eruption.
文摘In this study, we presented new theory of effusive and explosive of volcanic eruptions. New explanation of eruption mechanisms was done by using the Elemental Buoyancy Theory and new K-Th-U structure of Earth, developed early by author. During investigation of effusive eruptions, it was given clear answer on the question why the light chemical elements, mainly silicon and sulfur compound, currently dominate in the volcanic ashes, gases, and in the magma lavas. At investigation of explosive mechanism, we analyzed 38 strong eruptions with Volcanic Explosivity Index (VEI) more than 4+. It was shown that there is a link between the planet configurations and volcanic eruptions. It can be found that volcano eruptions occurred at the different types of planet alignments. The phenomenon does depend neither on planet mass nor on the relative positions of planets. Also the phenomenon does not depend on the distance between planets, but often eruptions were observed when the distances between planets are multiple units. Also in work, it was demonstrated that the planet alignment affects not only natural processes on the Earth, but also impact the Sun activity. Based on the comparison phenomenon on the Earth and Sun, we get new mechanism to rapidly rising up pressure under the lithospheric planes by gravity vortexes. This gravity vortex was called as terrestrial magmatic protuberances.
基金National Natural Science Foundation of China,No.41430528。
文摘ENSO is an interannual mode which may be affected by external forcing, such as volcanic eruptions. Based on the reconstructed volcanic eruptions chronology and ENSO sequences, both 195 large volcanic eruptions (VEI≥4) and 398 ENSO (El Niño and La Niña) events were extracted from 1525 to 2000. An analysis of the correspondence between the large volcanic eruptions and ENSO events was performed by matching the large volcanic eruptions with the types and magnitudes of ENSO events present in the 0-2 years after the eruptions. The results show the following: (1) The percentages of ENSO events within the 3 years after the large eruptions had increased to 68.3% from 31.7% compared with those with no-eruptions in the previous 0-2 years. In addition, the ratio of El Niño to La Niña events turned from 2:3 to 1:1, and more El Niño events occurred in the 0 year after eruptions in the low-latitudes of the Northern Hemisphere and in the tropics but more La Niña events occurred in the 0 year after in the high-latitudes of the Northern Hemisphere and the Southern Hemisphere. (2) After the eruptions, the weak (W) El Niño events had increased by 8 percentage points and the very strong (VS) El Niño events had decreased by 10 percentage points; conversely, there was a decrease by 15 percentage points of the weak La Niña events and an increase by 11.4 percentage points of the very strong La Niña events. Specifically, the percentages of strong La Niña events increased to a peak at 1 (+1) year after the eruptions. (3) The percentage of eruptions followed by single-year ENSO was the greatest. The percentage of ENSO events that occurred in the consecutive 2 years following an eruption was approximately equal to the percentage of events that occurred consecutively 3 years following an eruption, and both sets of ENSO magnitudes showed a decreasing trend.
文摘Based on data in the last 500 years for strong volwtc aedvity and the sununer drought/flood types available in China, the statistical relatons 0f the volcanic eruptions in seasons and several ropons and the drowtood types and grade index of main wions in China have ban inveStigned. The possible teleconnection bforan flood in the Yangtze hiver and the Huaihe foveL Valleys in 1991 and the volcanic eruption of Mt. Pinatubo in June of 1991 has bam also exathened. It is found that ehas of volcanic eruption in differen ropons in the worid vary on droguood in diffend edons of China, but in some cases the the is absolutely opposite in respect of the summer drowood. Statshcal test shows that in terms of stud confidence levels of the reation for dividing the volcanic eruptions as several ropons are higher than that for volcanic eruPhon in the worid as Whole.
基金supported by Swedish Formas(2019-01520 and 2023-01648)the Natural Science Foundation of China(42488201 and 41975107)+2 种基金the Guangdong Major Project of Basic and Applied Basic Research(2020B0301030004)supported by the Sven Lindqvists Forskningsstiftelse,Stiftelsen L€angmanska Kulturfonden(BA24-0484)StiftelsenÅforsk(24-707)and Adlerbertska Forskningsstiftelsen(AF2024-0069).
文摘Near-surface wind speed(NSWS),a determinant of wind energy,is influenced by both natural and anthropogenic factors.However,the specific impacts of volcanic eruptions on NSWS,remain unexplored.Our simulations spanning the last millennium reveal a consistent 2-year global NSWS reduction following 10 major historical eruptions.This equates to an NSWS decrease of approximately two inter-annual standard deviations from AD 851 to 1849.This reduction is linked to the weakening of subtropical descending air and a decrease in downward momentum flux,triggered by volcanic aerosol forcing.The 1815 Tambora eruption,one of the most powerful in recent history,led to a~9.2%reduction in global wind power density in the subsequent 2 years.Our research fills a knowledge gap,establishes a theoretical foundation for empirical studies,and highlights the potential wind energy risks linked to large atmospheric aerosol injections,including volcanic eruptions,nuclear warfare,and climate intervention.
文摘The Asia-Pacific Region Global Earthquake and Volcanic Eruption Risk Management(G-EVER)Consortium among the Asia-Pacific geohazard research institutes was established in 2012 with the main objective of reducing the risk caused by earthquakes,tsunamis and volcanic eruptions worldwide.The first G-EVER workshop was held in Tsukuba,Japan in February 2012.The G-EVER1 accord was approved by the workshop participants which made 10 recommendations that focused on the enhancement of collaboration,sharing of resources and making information about the risks of earthquakes and volcanic eruptions freely available and understandable.
基金supported by the Natural Science Foundation of Jilin Province(20170101001JC)Natural Science Foundation of China(41472304)National Major Fundamental Research and Development Projects(2012CB822002)
文摘The Cenozoic volcanostratigraphy in the Changbaishan area had complex building processes.Twenty-two eruption periods have been determined from the Wangtian＇e, Touxi, and Changbaishan volcanoes. The complex volcanostratigraphy of the Changbaishan area can be divided into four types of filling patterns from bottom to top. They are lava flows filling in valleys（LFFV）, lava flows filling in platform（LFFP）, lava flows formed the cone（LFFC）, and pyroclastic Flow filling in crater or valleys（PFFC/V）. LFFV has been divided into four layers and terminates as a lateral overlap. The topography of LFFV, which is controlled by the landform, is lens shaped with a wide flat top and narrow bottom.LFFP has been divided into three layers and terminates as a lateral downlap. The topography of LFFP is sheet and tabular shaped with a narrow top and wide bottom. It has large width to thickness ratio. It was built by multiple eruptive centers distributed along the fissure. The topography of LFFC, which is located above the LFFP, has a hummocky shape with a narrow sloping top and a wide flat bottom. It terminates as a later downlap or backstepping. It has large width to thickness ratio. It was built by a single eruptive center. The topography of PFFC/V, which located above the LFFC, LFFP, or valley, has the shape of fan and terminates as a lateral downlap or overlap. It has a small width to thickness ratio and was built by a single eruptive center. The filling pattern is controlled by temperature, SiO_2 content,volatile content, magma volume, and the paleolandform. In the short term, the eruptive production of the Changbaishan area is comenditic ash or pumice of a Plinian type eruption. The eruptive volume in future should be smaller than that of the Baguamiao period, and the filling pattern should be PFFC/V,which may cause huge damage to adjacent areas.
基金supported by the National Natural Science Foundation of China(Grant Nos.42130604,42105044,41971108,42111530182&41971021)the Consultation and Review Project of Chinese Academy of Sciences(Grant No.2022-ZW04-A-010)+3 种基金the Swedish STINT(Grant No.CH2019-8377)the Future Earth Global Secretariat Hub Chinathe International Research Center of Big Data for Sustainable Development Goals(Grant No.CBAS2022GSP08)the Priority Academic Program Development of Jiangsu Higher Education Institutions(Grant No.164320H116).
文摘Major volcanic eruptions(MVEs)have attracted increasing attention from the scientific community.Previous studies have explored the climatic impact of MVEs over the past two millennia.However,proxy-based reconstructions and climate model simulations indicate divergent responses of global and China’s regional climates to MVEs.Here,we used multiple data from observations,reconstructions,simulations,and assimilations to summarize the historical facts of MVEs,the characteristics and mechanisms of their climatic impact,and directions for future research.We reviewed volcanic datasets and determined intensive MVE periods;these periods corresponded to the years 530–700,1200‒1460,and 1600‒1840 CE.After tropical MVEs,a substantial cooling effect is observed throughout the globe and China on the interannual-interdecadal time scales but an inconsistent cooling magnitude is detected between reconstructions and simulations.In the first summer after tropical MVEs,a decrease in global and monsoonal precipitation is observed.In reconstructions and simulations,an increased precipitation is seen for the Yangtze River Basin,while large uncertainties in precipitation changes are present for other regions of China.Decadal drought can be induced by frequent eruptions and volcanism superimposed on low solar irradiation and internal variability.MVEs affect climate directly through the radiative effect and indirectly by modulating internal variability,such as the El Niño‒Southern Oscillation(ENSO)and Atlantic Multidecadal Oscillation(AMO).However,changes in the phase,amplitude,and periodicity of ENSO and AMO after MVEs and the associated mechanisms remain controversial,which could account for model-reconstruction disagreements.Moreover,other internal variability,uncertainties in reconstruction methods and aerosol‒climate models,and climate background may also induce model-reconstruction disagreements.Knowledge gaps and directions for future research are also discussed.
基金Supported by the National Key Research and Development Program of China(2016YFA0600701)National Natural Science Foundation of China(41822502 and 41661144005)Joint Programming Initiative Climate—Belmont Forum Project InterDec。
文摘This study investigates the influences of strong tropical volcanic eruptions(SVEs) on daily temperature and precipitation extreme events using long-term simulations from the Hadley Centre Coupled Model version 3(HadCM3) and the Community Earth System Model version 1.1(CESM1). The results indicate that the occurrences of daily hot extremes and daily heavy precipitation extremes decrease over most parts of the world in the peak forcing years of SVEs. Due to the volcanic cooling effect, the average probability of daily hot extremes decreases by approximately 50% across the globe. The decrease in intensity is stronger for midlatitude land regions and tropical South America.In contrast, daily cold extremes occur more frequently over most parts of continental regions. Globally, a cold extreme event expected once every 3 years under non-volcanic conditions can be expected every 1.5 years on average in the peak forcing years. Overall, the SVE-induced cooling effect plays a dominant role in regulating daily cold and hot extremes. Over high-latitude Eurasian regions, in contrast to other continental regions, the probability and intensity of daily cold extremes decrease due to an SVE-strengthened polar vortex and the associated temperature advection anomalies. With regard to daily heavy precipitation extremes, the probability and intensity both decrease over most monsoon areas. Further analysis suggests that the reduced probability and intensity of daily heavy precipitation extremes are mainly due to the SVE-induced global decrease in the water-holding capacity.
文摘This thesis lists and describes 6 pairs of tectonic events, i.e ., historical volcanic eruptions associated with historical strong earthquakes, based on the analysis for the records of historical volcanic eruptions and historical strong earthquakes in China and its adjacent region since the first record. And discusses the relationship between historical eruptions and strong earthquakes by means of analyzing the characteristics of tectonic events themselves, plate movement, regional seismicity, and regional stress environment in China and its adjacent region.
文摘Based on the historical data of the excessivc rains ovcr the middle-lower reaches of Changjiang River in two hundred and fifty years (1651--1900) and the data of 'Very Large' volcanic eruptions (VEI≥5) in the period of 1650--1900, which are selected from the table of volcanic eruption year complied by Sim- kin et al. (198l). This paper analyses the interannual variation of various kinds of continuous rains in the historical period, as well as the relation between plum-continuous rains and waterlogging along Chang- jiang-Huaihe reaches, and between 'Very Large' volcanic cruption and continuous rains over the middle- lower reaches of Changjiang Rivex.
文摘When gigantic meteorite impact sites in Southern Africa are plotted on the geological map of the region,they overlap with the SW-NE fault lines and it indicates that meteorite impacts have contributed to the geological structure of the region.The Morokweng Meteorite Impact of 145 Ma(Million years ago),at the J/K(Jurassic/Cretaceous)boundary,seems to have broken up the Gondwanaland.It is plausible that,at the time of continental break-up,seawater poured into Morokweng crater and ignited a gigantic volcanic eruption which delivered low viscose magma into the outer space to form the Moon.An extremely flat surface of the Megakalahari extending 3,800,000 sq.km at 800-1,200 m above sea level in the central and southern Africa seems to be the terrestrial residue of fluid magma at the end of the volcanic event.
文摘The Longhai-Zhangpu coastal region lies in the so-called Golden Triangle area of southern Fujian Province. Tectonically, it is located on the southern segment of the Changle-Zhao＇an fault zone, being one of the regions of Tertiary and Quaternary basaltic eruptions in China＇s southeast coastal area. In this area there are the Liuhui （Longhai County ）-Jiangjun＇ ao （Zhangpu County） and Gangwei （ Longhai County ）-Huxi （ Zhangpu County ） faults, along which basaltic eruption has occurred. The faults have been significantly active since the Quaternary, and several small to moderate earthquakes have occurred on the faults. In this paper, the basic characteristics of the late Quaternary activities and the combination relation of the faults are discussed on the basis of an analysis of along-fault basaltic eruptions during the late Tertiary to late Pleistocene, as well as the differential variation of geomorphic surfaces and marine deposits on both sides of the faults. The results show that the Liuhui-Jiangjun＇ao fault is a late Pleistocene active fault. During the late Tertiary to late Pleistocene, three stages of basaltic eruptions occurred along the fault, among which the first stage occurred in the Pleistocene to early Pleistocene, the second stage in the middle Pleistocene and the third stage in the late Pleistocene. The Gangewei-Huxi fault can also be considered a late Pleistocene active fault. The elevation rate of the downthrown side of the fault is estimated to be 1. 11mm/a.These two faults have dissected the area into the Gangwei graben, south Taiwushan horst and the graben in the sea area to the east of Liuhul-Jiangjun＇ao.
基金supported by the Forest Science&Technology Projects(No.S111215L050110)provided by the Korea Forest Service,Republic of Korea
文摘This study was conducted in order to examine the influence of long-term volcanic activity on vegetative succession and growth on the slope of Sakurajima in southern Kyushu, Japan. We investigated the vegetation,depth of the volcanic ash layer, and dry density and p H of the surface soil at six places on the north-northwestern slope, 2.3–3.4 km from the Minami-dake crater, where a layer of pumice stone was deposited by the Taisho eruption in 1914. The height and diameter at breast height（DBH） of the trees increased with increasing distance from the Minami-dake crater, as did the number of individuals and species, and basal area. The Shannon–Wiener diversity index（H＇） demonstrates that vegetative succession is significantly affected by distance from the Minami-dake crater, as areas farther from the crater exhibited later seral stages. Comparison of the diversity index and species number of the crater region with that of the climax forest in Kagoshima indicates that vegetative growth alone cannot advance succession in the study area, as the local vegetative community is heavily influenced by the harsh environmental conditions associated with continual exposure to long-term volcanic activity. Seral stage, ash layer depth,dry density, and p H of the soil surface layer are governed by distance from the Minami-dake crater. The results of this study indicate that conditions for vegetative growth and succession improve with increasing distance from the source of constant volcanic activity. Thus, soil development is promoted by the acidification of the soil, which decreases the dry density and p H of the soil surface layer.The introduction of plant species resistant to volcanic ash and gas is recommended to promote soil development and improve the infiltration capacity of the soil.
基金supported by the project of the China Geological Survey(DD20221661).
文摘The black shales of Wufeng and Longmaxi Formation(Late Ordovician-Early Silurian period)in Sichuan Basin are the main strata for marine shale gas exploration,which have a yearly shale gas production of 228×10^(8)m^(3)and cumulative shale gas production of 919×10^(8)m^(3).According to the lithological and biological features,filling sequences,sedimentary structures and lab analysis,the authors divided the Wufeng/Guanyinqiao and Longmaxi Formations into shore,tidal flat,shoal,shallow water shelf and deep water shelf facies,and confirmed that a shallow water deposition between the two sets of shales.Although both Formations contain similar shales,their formation mechanisms differ.During the deposition of Wufeng shale,influenced by the Caledonian Movement,the Central Sichuan and Guizhou Uplifts led to the transformation of the Sichuan Basin into a back-bulge basin.Coinstantaneous volcanic activity provided significant nutrients,contributing to the deposition of Wufeng Formation black shales.In contrast,during the deposition of Longmaxi shale,collisions caused basement subsidence,melting glaciers raised sea levels,and renewed volcanic activity provided additional nutrients,leading to Longmaxi Formation black shale accumulation.Considering the basic sedimentary geology and shale gas characteristics,areas such as Suijiang-Leibo-Daguan,Luzhou-Zigong,Weirong-Yongchuan,and Nanchuan-Dingshan are identified as key prospects for future shale gas exploration in the Wufeng-Longmaxi Formations.
基金supported by the Research Grant Council of the Hong Kong Special Administrative Region,China(Grant No.17309121)the National Natural Science Foundation of China(Grant No.41303080)+1 种基金the Youth Innovation Promotion Association CAS(Grant No.2018499)the USTC Research Funds of the Double First-Class Initiative(Grant No.YD2110002027)。
文摘Volcanic eruptions potentially threaten local and global environments,making it crucial to reconstruct their eruption history for risk assessments and forecasts.However,accurately dating of young(e.g.,Holocene)volcanoes remains challenging.For example,K-Ar and^(40)Ar/^(39)Ar dating are potentially problematic due to the long half-lives of radioisotopes,while radiocarbon dating requires organic materials.The study used optically stimulated luminescence(OSL)dating on quartz to accurately constrain the ages of lava-baked sediments from the Tengchong volcanic field,southeastern margin of the Tibetan Plateau.The results show two types of quartz OSL characteristics in the initial OSL signals.The first type,dominated by the fast component,yields reliable OSL ages.In contrast,the second type,dominated by the medium component,shows a negative correlation between equivalent dose(D_(e))and recuperation,and a decreasing trend in D_(e)over illumination time,providing the underestimated ages due to the influence of the unstable medium component.These underestimated OSL ages are corrected using the D_(e)-recuperation plot.Combining with previous chronological studies,we conclude that Tengchong volcanoes have erupted at least seven times during the Holocene,occurring at 11.6–11.1,≤11.4–10.3,5.9–5.7,5.0–4.8,3.5–2.5,2.0 thousand years ago,and1609 AD.D_(e)spite the current stability of the Tengchong volcanoes,frequent tectonic activities,eruptive history,and the presence of active magma chambers suggest the potential for future volcanic eruptions.
基金funded by the Ministry of Science and Higher Education of the Russian Federation(agreement No.075-15-2022-1127 dated July 1,2022).
文摘The paper considers a catastrophic event-the eruption of Hunga Tonga-Hunga Ha’apai volcano on January 15,2022.The process of preparation and eruption of Hunga Tonga volcano generated tsunami waves that were observed throughout the World Ocean.This event was notable for its unprecedented global impact and the early appearance of tsunami waves at distant coastal stations.So,the first waves at tide gauge stations in Chile and Peru were recorded 4 hours earlier than the arrival time of tsunami waves to the tide gauge after the eruption of Tonga volcano.Two mechanisms are possible for the generation of early tsunami waves:acoustic Lamb waves generated by a volcanic explosion and submarine landslides that occurred on the slopes of the volcano during the preparatory phase of the eruption.In this study,numerical simulation of various pre-eruption landslide scenarios on the slope of Hunga Tonga volcano is carried out in an attempt to explain these early tsunami waves.Under computation the elastoplastic model of landslide was taken into account.Wave characteristics of a tsunami on the coast of Chile and Peru generated by a landslide process on a volcanic slope are obtained.A detailed comparison of virtual tide gauge data with observational ones is used to validate this model.The results obtained can be used to improve early warning systems.
