Indirect Volcanic Hazards: Famine

Sometimes deaths occur not due to the natural disaster itself but rather from indirect reasons; disasters can cause crops to fail, rivers to flood, and so on.

Laki, Iceland Fissure Eruption of 1783

During the 1973 eruption of Laki in Iceland, large quantities of SO₂ and fluorine gases were released. No one was killed due to the lava, but the gases killed 75% of Iceland’s sheep & horses and 50% of Iceland’s cattle. This lead to famine, which killed 20% of Iceland’s population.

Tambora, Indonesia, 1815

The 1815 eruption of Tambora was one of the most powerful volcanic eruptions in historic times. Classified as a VEI 7, the eruption on April 5, 1815 was so loud it was heard on Ternate on the Molucca Islands 1,400 km (870 mi) away. Loud eruptions continued for several days. On April 10th a final, climatic eruption occurred, and this time the sound was heard more than 2,600 km (1,600 mi) away in Sumatra. Ash fell over a distance of 1,300 km (810 mi). Trees on the island were felled, a moderate tsunami with 4 m high waves struck nearby islands, and pumice choked the nearby waters. However, it as the large quantity of pyroclastic fallout - mostly ash - that destroyed crops in Indonesia and lead to famine in the area. The finer ash particles stayed in the atmosphere for at least a few months. This affected global climate; 1816 is often refered to as the “year without a summer”. Crops failed and cool, wet weather was reported all over Europe, Asia, the New England states and Eastern Canada. And rivers that normally remained unfrozen in winter froze over.

There were some good outcomes of the eruption. One, beautiful sunsets were reported all over the northern hemisphere as a result of all the ash in the atmosphere. Two, all these beautiful sunsets inspired many painters, and today we have numerous landscapes with sunsets dating from this time. Third, the dreary weather forced writers Mary Shelley and Lord Byron to spend their Swiss holiday inside, which resulted in the writting of "Frankenstein" by Shelley, and "A Fragment" and "Darkness" by Byron.

Sunset painting by J.M.W. Turner, possibly due to the atmospheric effects of the Tambora eruption.
Painting of a frost fair on the River Thames, London, England. Conditions during the Little Ice Age often caused rivers to freeze over. However, this freezing event is likely due to the 1815 Tambora eruption.

 

Professor Sonjia Leyva
	CSULA Department of Geosciences and the Environment
	Pasadena City College Department of Geology