Spatial and Temporal Quantification of Subaerial Volcanism From 1980 to 2019:...

Galetto, F., M. E. Pritchard, A. J. Hornby, E. Gazel, and N. Mahowald (2023), Spatial and Temporal Quantification of Subaerial Volcanism From 1980 to 2019: Solid Products, Masses, and Average Eruptive Rates, Rev. Geophys..

Volcanism is one of the main mechanisms transferring mass and energy between the interior of the Earth and the Earth's surface. However, the global mass flux of lava, volcanic ash and explosive pyroclastic deposits is not well constrained. Here we review published estimates of the mass of the erupted products from 1980 to 2019 by a global compilation. We identified 1,064 magmatic eruptions that occurred between 1980 and 2019 from the Smithsonian Global Volcanism Program database. For each eruption, we reported both the total erupted mass and its partitioning into the different volcanic products. Using this data set, we quantified the temporal and spatial evolution of subaerial volcanism and its products from 1980 to 2019 at a global and regional scale. The mass of magma erupted in each analyzed decade ranged from 1.1–4.9 × 10 13 kg. Lava is the main subaerial erupted product representing ∼57% of the total erupted mass of magma. The products related to the biggest eruptions (Magnitude ≥6), with long recurrence times, can temporarily make explosive products more abundant than lava (e.g., decade 1990–1999). Twenty-three volcanoes produced ∼72% of the total mass, while two different sets of 15 volcanoes erupted >70% of the total mass of either effusive or explosive products. At a global scale, the 10 and 40-year average eruptive rates calculated from 1980 to 2019 have the same magnitude as the long-term average eruptive rates (from thousand to millions of years), because in both cases rates are scaled for times comparable to the recurrence time of the biggest eruptions occurred. Plain Language Summary The impact of volcanism on the Earth system depends on how the magma is erupted at the surface. Lava effects are very strong locally, while ash emissions can impact larger areas. However, the total mass of magma erupted, as well as the mass of each volcanic product (effusive: lava; explosive: ash and pyroclastic flows) remain poorly constrained. Here we investigated the temporal and spatial evolution of global subaerial volcanism by quantifying the mass of each solid volcanic product erupted above the sea level from 1980 to 2019. Results show that at a global scale the subaerial volcanism produced 1.1–4.9 × 10 13 kg of magma per decade from 1980 to 2019. Lava is the main subaerial product representing ∼57% of the total erupted mass of magma. Combined with already available datasets, our work furthers future investigations of the relationship between the erupted masses of magma and of volatiles, the variation of the eruptive rates after an earthquake, the impact of the erupted mass on the Geospheres at local and global scales. Finally, mass balancing between the erupted and intruded mass could provide information of whether a volcano or a magmatic province is accumulating magma, potentially increasing future eruptive hazards on a decadal timescale.

Research Program: 
Interdisciplinary Science Program (IDS)
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