Reassessing the cooling that followed the 1991 volcanic eruption of Mt. Pinatubo

[Geoengineering News]

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https://www.sciencedirect.com/science/article/abs/pii/S1364682624000154

Authors

Alberto Boretti

15 February 2024

https://doi.org/10.1016/j.jastp.2024.106187

Highlights

•A novel approach is used, based on best fitting with a polynomial, multiple sinusoids and a rectangular function of temperature time series.

•The impact of the 1991 volcanic eruption of Mt. Pinatubo is assessed as a departure from this trend.

•The volcanic eruption had smaller effects than believed.

•Global cooling was less than 0.5 °C lasting fewer than 18–36 months, respectively 0.2 °C and 13 months.

•Solar geoengineering is likely less effective than assumed, with more side effects.

Abstract

A cooling of up to 0.5 °C which lasted 18–36 months is attributed to the 1991 Mt. Pinatubo eruption. A simple mathematical approach is here applied to the 43-year-long satellite global temperature time series. This time series is fitted with a parabolic function representing global warming, multiple sinusoidal functions representing natural variability, and a rectangular function representing the cooling of Mt. Pinatubo. The cooling is estimated at up to 0.28 °C, 0.2 °C on average. Similarly shorter is the duration of the cooling, about 13 months. This result impacts the risk-to-benefit ratio of SAI which may be worse than thought.

Source: ScienceDirect 

[Jeff Suchon]

The author concludes in his bullet item list that solar geoengineering is less effective than assumed. Firstly, he should say "SAI" because MCB and surface reflection are in the solar geoengineering umbrella. And, the volcano was not SAI. SAI is STRATEGIC.