pinatubo 1991

Twenty-three years ago this weekend, on June 15, 1991, Mt. Pinatubo, on the island of Luzon in the Philippines, erupted. This was the second-largest volcanic eruption of the 20th century, easily surpassing that of Mt. St. Helens in 1980, and ejected more particulate matter into the atmosphere than any other single eruption since that of Krakatoa in August 1883. As my historical research involves volcanic climate change–it’s the reason why I’m in southern California this week–the Pinatubo anniversary is significant. While the 1991 Pinatubo eruption didn’t have the same global environmental effects as the catastrophic Tambora eruption of 1815, which is my subject, it’s still very interesting, and also significant to me personally because of one interesting memory I didn’t connect with it at the time.

The eruption itself was plenty destructive, but would have been much more so if not for the vigilance of geologists and authorities in the Philippines. Pinatubo stirred to life earlier that year, in April, and large-scale evacuations of the 300,000 people who lived near it began piecemeal during that time. As with Mt. St. Helens in 1980, not that many people were left by the time the mountain finally blew its top on June 15. Of course, “not that many people” is a relative thing when talking about a nation as populous as the Philippines. Plenty still remained. About 840 people died as a direct result of the cataclysm, most killed by building collapses from the weight of wet ash. Oh, did I mention that Mt. Pinatubo erupted at the same time as a typhoon hit the Philippines? Wet ash forms a sort of impenetrable paste. It can–and did in this case–foul water sources, villages, and engines of cars and airplanes. Infrastructure and health care services, never very reliable in the Philippines, began to break down in the weeks after the eruption, resulting in many more indirect deaths that probably could have been prevented. Many thousands were left homeless or had their livelihoods destroyed by the ash and mud flows.

Worldwide, Pinatubo did have an effect, though not the same one as the great volcanic eruptions of the 19th century. The sulfur dioxide that Pinatubo pumped into the upper atmosphere did lower global temperatures slightly and also affected the ozone layer, already fragile from human-caused pollutants. But a “Year Without Summer” did not happen following Pinatubo. For one thing the eruption wasn’t large enough. For another, the effects of man-made climate change (greenhouse gas warming) deadened the effect. But that didn’t mean the skies weren’t still full of Pinatubo’s junk. They were.

pinatubo colors

This picture, showing the particulates in the atmosphere in the wake of the Pinatubo eruption, was taken from the Space Shuttle on August 8, 1991, only two weeks before I saw the memorable sunset in New Mexico–which looked very much like this.

On August 23, 1991, I remember seeing one of the two most spectacular sunsets I’ve ever seen in my life. I spent that evening on the lawn in front of my dorm at the University of New Mexico, watching my friends play volleyball. The colors of the sunset were almost indescribable. There were oranges, red, gold, pink, rose and all shades in between, and the sky was luminous and glowing, like a romanticist painting. I never forgot that sunset and I never will. It was simply stunning.

It was also a direct result of the eruption of Mt. Pinatubo. I didn’t realize this at the time; I don’t remember hearing about the eruption when it happened. But, as I’ve uncovered in my own research about the 19th century, brilliant sunsets, even in the Northern Hemisphere, always follow a massive stratospheric volcanic eruption–to the point that, knowing when the major eruptions occurred in the early 19th century, I know that in diaries and meteorological sources I’ll begin to see reports of spectacular sunsets. I have been able to connect all the major eruptions of the “Cold Decade” of the 1810s (Mt. Etna 1809, Mt. Mayon and Soufriere 1812, Mt. Awu 1814, Tambora 1815) to sources mentioning spectacular sunsets in the United States and England. Similarly, the spectacular sunsets in the late summer and early fall of 1991 are attributable to Mt. Pinatubo. Ironic that this phenomena, which would figure so prominently in my adult life, went unnoticed when it happened in real-time in my youth.

Incidentally, the other most amazing sunset I ever saw was also connected with a volcanic eruption–but that’s a story for another time!