A similar cataclysmic eruption occurred in April 1815, Tambora Volcano, Indonesia, the most powerful eruption recorded in history.
Tambora's volcanic clouds lowered the global temperatures
by as much as 3 deg. C.
Even a year after the eruption, most of the northern hemisphere recorded sharply cooler temperatures during summers- 1816 was a year without a summer in parts of Europe and N. America.
Apart from possibly affecting climate, volcanic clouds from explosive eruptions also pose a hazard to aviation safety- encounter with volcanic ash.
Since A.D. 1600, nearly 300,000 people have been killed in volcanic eruptions.
Pyroclastic flows and mudflows that often accompany subduction zone volcanic eruptions caused most of these deaths.
Pyroclastic Flows, or nuees ardentes (glowing clouds in French) are fast -moving ( > 150 km/hr), avalanche- like, ground – hugging incandescent mixtures of hot volcanic debris, ash, and gases. Some 30,000 people were killed by 1902 Mont Pelee eruption.
In March-April 1982, 3 explosive eruptions of El Chichon Volcano, Chiapas, SE Mexico, produced pyroclastic flows that killed more than 2000 people and devastated villages within 8 km of the volcano.
Mudflows (also called debris flows or lahars, an Indonesian term for volcanic mudflows) are mixtures of volcanic debris and water.
The water comes from two sources: rainfall or the melting of snow and ice by hot volcanic debris.
Depending upon the proportion of water to volcanic debris, mudflows range from hypoconcentrated flows to wet-cement consistency, thick flows.
These flows have tremendous strength, they travel fast, and can flatten and bury every thing in their path.
Hot ash and pyroclastic flows from the eruption of the Nevado del Ruiz Volcano in Colombia melted snow and ice atop the 5,390 high Andean Peak;
the ensuing mudflows buried the city of Armero, killing 25,000 people.