Year Without a Summer

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Year Without a Summer
1816 summer temperature anomaly compared with average temperatures from 1971 to 2000
Volcano	Mount Tambora
Start date	Eruption occurred on 10 April 1815
Type	Ultra-Plinian
Location	Lesser Sunda Islands, Dutch East Indies (now Republic of Indonesia)
Impact	Caused a volcanic winter that dropped temperatures by 0.4–0.7°C (or 0.7–1°F) worldwide

The year 1816 AD is known as the Year Without a Summer because of severe climate abnormalities that caused average global temperatures to decrease by 0.4–0.7 °C (0.7–1 °F).^[1] Summer temperatures in Europe were the coldest of any on record between 1766 and 2000,^[2] resulting in crop failures and major food shortages across the Northern Hemisphere.^[3]

Evidence suggests that the anomaly was predominantly a volcanic winter event caused by the massive 1815 eruption of Mount Tambora in April in the Dutch East Indies (modern-day Indonesia). This eruption was the largest in at least 1,300 years (after the hypothesized eruption causing the volcanic winter of 536); its effect on the climate may have been exacerbated by the 1814 eruption of Mayon in the Philippines.