wunder beta🌋 Tambora, Krakatau and the year without a summer
Two Indonesian eruptions, 68 years apart, are constantly confused. Tambora in 1815 killed through ash and famine and then stole a summer from the other side of the world; Krakatau in 1883 killed through water. Follow the sulfur up into the
What you’ll learn
- Two eruptions, one archipelagoSeparate Tambora and Krakatau by date, place, size and cause of death, so the two stories stop contaminating each other.Tambora erupted in April 1815 on Sumbawa and killed mostly through ash and famine; Krakatau erupted in August 1883 in the Sunda Strait and killed mostly through tsunami. They are 68 years and about a thousand kilometres apart.
- What makes an eruption climate-sizedExplain why the altitude and chemistry of what an eruption injects matters more than the volume of rock it moves.Ash falls out locally within weeks. Sulfur dioxide delivered into the stratosphere becomes a sulfate haze that scatters sunlight for a year or two — and Tambora delivered around 60 teragrams of it.
- Krakatau, August 1883Trace how a single eruption produced four distinct hazards on four timescales, and why the deadliest one travelled by sea.Blast, pyroclastic surges across 40 km of open water, caldera collapse and tsunami arrived as one chain. Over 34,000 of the roughly 36,000 deaths came from the waves, while the atmospheric evidence reached every continent.
- The year without a summerConnect Tambora's aerosol veil to the specific, regionally uneven weather of 1816 and to its social consequences.1816 brought frost and June snow to New England and incessant rain to western Europe. What turned bad weather into hardship was crops, debts, markets and institutions — and one wet summer on Lake Geneva produced Frankenstein.
- How we know, and what nobody knowsJudge what makes a historical climate attribution strong, and identify what remains genuinely unresolved.Nobody in 1816 suspected a volcano. The link was reconstructed from ice cores, tree rings, diaries and models agreeing on one year for one physical reason — and that same evidence records a second large eruption around 1809 whose volcano has never been identified.
Questions this course answers
Which eruption is the one linked to the disrupted growing season of 1816?
Tambora's climax came on the evening of 10 April 1815, more than a year before the 1816 season. Krakatau erupted 68 years later and cannot be the cause.
What caused the great majority of deaths at Krakatau in 1883?
NOAA attributes more than 34,000 of roughly 36,000 deaths to tsunami generated when the island collapsed into the shallow Sunda Strait.
What actually gives an eruption a climate effect?
Ash falls out within weeks. Sulfur dioxide that reaches the stratosphere becomes sulfate droplets that scatter sunlight and linger for a year or two.
Roughly how much sulfur dioxide did Tambora put into the stratosphere?
Around 60 Tg, a figure derived from Self and colleagues and used in the peer-reviewed literature on the eruption's climate effects.
What is the correct name of the volcano in the Sunda Strait?
The Smithsonian Global Volcanism Program uses Krakatau and notes that it is 'frequently misnamed as Krakatoa'. Rakata is the surviving remnant cone.
The famous lithograph of a huge column above Krakatoa actually shows what?
The Royal Society's own caption reads 'from a Photograph taken on Sunday the 27th of May, 1883' — three months before the catastrophe.
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