<P> Justus von Liebig, a chemist who had experienced the famine as a child in Darmstadt, later studied plant nutrition and introduced mineral fertilizers . </P> <Table> <Tr> <Td> </Td> <Td> This section does not cite any sources . Please help improve this section by adding citations to reliable sources . Unsourced material may be challenged and removed . (May 2018) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This section does not cite any sources . Please help improve this section by adding citations to reliable sources . Unsourced material may be challenged and removed . (May 2018) (Learn how and when to remove this template message) </Td> </Tr> <Ul> <Li> Toba catastrophe 70,000 to 75,000 years ago </Li> <Li> The 1628--1626 BC climate disturbances, usually attributed to the Minoan eruption of Santorini </Li> <Li> The Hekla 3 eruption of about 1200 BC, contemporary with the historical Bronze Age collapse </Li> <Li> The Hatepe eruption (sometimes referred to as the Taupo eruption), around AD 180 </Li> <Li> Extreme weather events of 535--536 have been linked to the effects of a volcanic eruption, possibly at Krakatoa, or Ilopango in El Salvador . </Li> <Li> The Heaven Lake eruption of Paektu Mountain between North Korea and the People's Republic of China, in 969 (± 20 years), is thought to have had a role in the downfall of Balhae . </Li> <Li> The 1257 Samalas eruption of Mount Rinjani on the island of Lombok in 1257 </Li> <Li> An eruption of Kuwae, a Pacific volcano, has been implicated in events surrounding the Fall of Constantinople in 1453 . </Li> <Li> An eruption of Huaynaputina, in Peru, caused 1601 to be the coldest year in the Northern Hemisphere for six centuries (see Russian famine of 1601--1603); 1601 consisted of a bitterly cold winter, a cold, frosty, late (possibly nonexistent) spring, and a cool, wet summer . </Li> <Li> An eruption of Laki, in Iceland, caused thousands of fatalities in Europe, 1783--84 . </Li> <Li> The 1883 eruption of Krakatoa caused average Northern Hemisphere summer temperatures to fall by as much as 1.2 ° C (2.2 ° F). </Li> <Li> The eruption of Mount Pinatubo in 1991 led to odd weather patterns and temporary cooling in the United States, particularly in the Midwest and parts of the Northeast . An unusually mild winter was followed by an unusually cool, wet summer and a cold, early autumn in 1992 (cooler - than - normal July, August, September, and October in 1992). Enhanced rainfall occurred across the West Coast of the United States, particularly California, during the 1991--92 and 1992--93 rainy seasons, and the American Midwest experienced elevated levels of rainfall, and consequent major flooding, during the spring and summer of 1993 . </Li> </Ul>

The year without a summer in the united states