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Volcanic Eruption Cools Southern Hemisphere, Raises Geoengineering Concerns

4/3/2025

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Summary

Story summary

The Hunga Tonga–Hunga Ha‘apai volcano's dramatic eruption on January 15, 2022, unexpectedly chilled the Southern Hemisphere by 0.1°C. A UCLA study revealed that tiny sulfate aerosols from the blast reflected sunlight, countering warming from water vapor. This finding raises alarms about the dangers of geoengineering methods that manipulate our atmosphere.

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Story summary

The Hunga Tonga–Hunga Ha‘apai volcano's dramatic eruption on January 15, 2022, unexpectedly chilled the Southern Hemisphere by 0.1°C. A UCLA study revealed that tiny sulfate aerosols from the blast reflected sunlight, countering warming from water vapor. This finding raises alarms about the dangers of geoengineering methods that manipulate our atmosphere.