She has been searching information about Mount Tambora, the active Indonesian stratovolcano, whose eruption in 1815 affected Earth's climate for the next two years and was the largest in recorded human history and the largest of the Holocene.
Mount Tambora, or Tomboro, is an active stratovolcano in West Nusa Tanagra, Sumbawa, Indonesia in one of the Lesser Sunda Islands of Indonesia.
It was formed due to the active subduction zones beneath it, and before its 1815 eruption, it was more than 4,300 metres high, making it one of the tallest peaks in the Indonesian archipelago.
Tambora's 1815 eruption was the largest in recorded human history and the largest of the Holocene, 10,000 years ago to present.
The magma chamber under Tambora had been drained by previous eruptions and underwent several centuries of dormancy as it refilled. Volcanic activity reached a peak that year, culminating in an explosive eruption. The explosion was heard on Sumatra island, more than 2,000 kilometres away.
Heavy volcanic ash rains were observed as far away as Borneo, Sulawesi, Java and Maluku islands, and the maximum elevation of Tambora was reduced from about 4,300 metres to 2,850 metres. Although estimates vary, the death toll was at least 71,000 people. The eruption contributed to global climate anomalies in the following years, while 1816 became known as the year without a summer due to the impact on North American and European weather. In the Northern Hemisphere, crops failed and livestock died, resulting in the worst famine of the century.
More information: Smithsonian Magazine
Mount Tambora, also known as Tomboro, is situated in the northern part of Sumbawa island, part of the Lesser Sunda Islands. It is a segment of the Sunda Arc, a chain of volcanic islands that make up the southern chain of the Indonesian archipelago.
Tambora forms its own peninsula on Sumbawa, known as the Sanggar peninsula. To the north of the peninsula is the Flores Sea and to the south is the 86 kilometres long and 36 kilometres wide Saleh Bay. At the mouth of Saleh Bay there is an islet called Mojo.
Besides the seismologists and vulcanologists who monitor the mountain's activity, Mount Tambora is an area of interest to archaeologists and biologists. The mountain also attracts tourists for hiking and wildlife activities, though in small numbers. The two nearest cities are Dompu and Bima. There are three concentrations of villages around the mountain slope. At the east is Sanggar village, to the northwest are Doro Peti and Pesanggrahan villages, and to the west is Calabai village.
There are two routes of ascent to the caldera. The first begins at Doro Mboha village on the southeast of the mountain and follows a paved road through a cashew plantation to an elevation of 1,150 metres. The road terminates at the southern part of the caldera, which at 1,950 metres is reachable only by hiking. This location is only one hour from the caldera, and usually serves as a base camp from which volcanic activity can be monitored. The second route starts from Pancasila village at the northwest of the mountain and is only accessible on foot. The 16 kilometres hike from Pancasila at 740 metres elevation to the caldera of the volcano takes approximately 14 hours with several stops en route to the top. The trail leads through dense jungle with wildlife such as Elaeocarpus batudulangii, Asian water monitor, reticulated python, hawks, orange-footed scrubfowl, pale-shouldered cicadabird (Coracina dohertyi), brown and scaly-crowned honeyeater, yellow-crested cockatoo, yellow-ringed white-eye, helmeted friarbird, wild boar, Javan rusa and crab-eating macaques.
Before 1815, Mount Tambora
was dormant for several centuries as hydrous magma cooled gradually in a
closed magma chamber. Inside the chamber, at depths of 1.5 to 4.5
kilometres, cooling and partial crystallization of the magma exsolved
high-pressure magmatic fluid. Overpressure of the chamber of about 4,000
to 5,000 bars was generated as temperatures ranged from 700 to 850 °C.
In 1812, the crater began to rumble and generated a dark cloud.
More information: NASA-Earth Observatory
A moderate-sized eruption on 5 April 1815 was followed by thunderous detonation sounds that could be heard in Makassar on Sulawesi, at a distance of 380 kilometres, Batavia (now Jakarta) on Java, 1,260 kilometres away, and Ternate on the Molucca Islands at 1,400 kilometres from Mount Tambora. What was first thought to be the sound of firing guns was heard on 10 and 11 April on Sumatra island, more than 2,600 kilometres away. On the morning of 6 April 1815, volcanic ash began to fall in East Java, with faint detonation sounds lasting until 10 April.
The 1815 Tambora eruption is the largest and most devastating observed eruption in recorded history; a comparison with other major eruptions is listed below. The explosion was heard 2,600 kilometres away, and ash deposits were registered at a distance of at least 1,300 kilometres. A pitch of darkness was observed as far away as 600 kilometres from the mountain summit for up to two days. Pyroclastic flows spread to distances of about 20 kilometres from the summit and an estimated 9.3–11.8 × 1013 g of stratispheric sulfate aerosols were generated by the eruption.
The 1815 eruption released 10 to 120 million tons of sulphur into the stratosphere, causing a global climate anomaly.
Different methods have been used to estimate the ejected sulfur mass: the petrological method, an optical depth measurement based on anatomical observations, and the polar ice core sulfate concentration method, which calibrated against cores from Greenland and Antarctica.
In the spring and summer of 1816, a persistent stratospheric sulfate aerosol veil, described then as a dry fog, was observed in the northeastern United States. It was not dispersed by wind or rainfall, and it reddened and dimmed sunlight to an extent that sunspots were visible to the naked eye. Areas of the northern hemisphere suffered extreme weather conditions and 1816 became known as the year without a summer. Average global temperatures decreased about 0.4 to 0.7 °C, enough to cause significant agricultural problems around the globe. After 4 June 1816, when there were frosts in Connecticut, cold weather expanded over most of New England.
On 6 June 1816, it snowed in Albany, New York and Dennysville, Maine. Similar conditions persisted for at least three months, ruining most crops across North America while Canada experienced extreme cold. Snow fell until 10 June near Quebec City, accumulating to 30 centimetres.
More information: National Geographic
than man makes in a whole year.
And when you look at this 'climate change,'
and when you look at the regular climate change
that we all have in the world,
we have warm and we have cooling spells.
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