Effects of the 1815 Tambora Eruption to the Atmosphere and

Majalah Geologi Indonesia, Vol. 26 No. 2 Agustus 2011: 65-71
Effects of the 1815 Tambora Eruption
to the Atmosphere and Climate
Dampak Erupsi Tambora 1815
terhadap Atmosfir dan Iklim
Igan S. Sutawidjaja
Geological Agency, Jln. Diponegoro 57 Bandung
ABSTRACT
The eruption of Tambora Volcano on the island of Sumbawa in 1815 is generally considered as the
largest and most violent volcanic event in recorded history. The cataclysmic eruption occurring on
11 April 1815 was initiated by a plinian eruption on 5 April and killed more than 92,000 people in
Sumbawa and nearby Lombok. It is well-known as the largest eruption in historical time. This event
has an unprecedented impact on the Earth’s atmosphere as huge quantities of erupted ash and volcanic
aerosols inferred with incoming solar radiation to the earth, causing global climate changes for one to
two years. These changes were particularly well documented in temperate latitudes of the Northern
Hemisphere. This catastrophic eruption was documented by a handful of British resident agents, a
sea captain, and an army officer who were scattered in the Indonesian Archipelago. The aerosol cloud
spread rapidly around the Earth in about three weeks and attained global coverage by about one year
after the eruption. This caused dramatic decreases of the amount of net radiation reaching the Earth’s
surface. Effects on the climate were an observed surface cooling in the Northern Hemisphere of up to
0.4 to 0.7o C, equivalent to a hemispheric-wide reduction in net radiation of 6 watts per square meter
and a cooling of perhaps as large as -0.6oC over large parts of the Earth in 1816 and caused the year
without a summer.
Keywords: Tambora volcano, volcanic ash, volcanic aerosol, climatic effect
SARI
Erupsi Gunung api Tambora di Pulau Sumbawa pada 1815 dianggap sebagai kejadian terbesar dan
terdahsyat dalam catatan sejarah. Erupsi kataklismik yang terjadi pada 11 April 1815 diawali dengan
erupsi plinian pada 5 April dan membunuh lebih dari 92.000 jiwa di sekitar Sumbawa dan Lombok.
Erupsi ini terkenal sebagai letusan terbesar dalam kurun sejarah. Kejadian ini mempunyai dampak
yang tidak diketahui sebelumnya terhadap atmosfir bumi yaitu menghasilkan sejumlah besar abu
dan aerosol vulkanik, yang menutup radiasi sinar matahari terhadap bumi, sehingga menyebabkan
perubahan iklim dunia dalam satu sampai dua tahun. Perubahan ini terdokumentasi baik di belahan
bumi bagian utara. Erupsi katastrofik ini juga tercatat oleh beberapa aparat residen, kapten laut, dan
perwira angkatan darat Inggris yang saat itu berada di sekitar Kepulauan Indonesia. Awan aerosol
menyebar secara cepat ke sekeliling bumi dalam waktu tiga minggu, dan menutupi sekeliling dunia
dalam 1 tahun setelah erupsi. Hal ini menyebabkan penurunan dramatis sejumlah jaringan radiasi yang
mencapai permukaan bumi. Dampak perubahan iklim tersebut teramati dengan adanya penurunan
suhu permukaan di belahan utara mencapai 0,4o sampai 0,7o C, yang ekuivalen dengan reduksi luas
belahan dalam jaringan radiasi sebesar 6 watt per meter persegi, dan pendinginan sebesar -0,6o C
pada area yang luas di permukaan bumi pada tahun 1816, sehingga menimbulkan kehilangan musim
panas pada tahun itu.
Kata kunci: Gunung Tambora, abu vulkanik, aerosol vulkanik, dampak iklim
Naskah diterima: 07 April 2011, revisi terakhir: 29 Juli 2011
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Majalah Geologi Indonesia, Vol. 26 No. 2 Agustus 2011: 65-71
INTRODUCTION
relatively modest height struck the shores
of the Indonesian islands on 10 April. The
wave rose to a maximum height of 4 m at
Sanggar for a short time around 10 p.m. and
reached Besuki in East Java (500 km away)
with a height of 1 to 2 m, before midnight.
Therefore, its average velocity must have
been of 70 m/sec. Travel time for a wave
between Tambora and Besuki was estimated
to be about 2 hours. The tsunami was also
observed in Maluku Islands with a wave
height of over 2 m. The physical cause of
the tsunami was probably the sudden entry
of the pyroclastic flows into the sea that
was reported to have taken place in the
three coastal towns; Tambora, Sanggar, and
Bima. Another tsunami reached Sumenep in
Madura at 7 p.m. on 11 April with a height
of about 1 m.
The Tambora Volcano situated in the
northern part of Sumbawa Island occupies
the Sanggar Peninsula (Figure 1). Eruption
of the Tambora Volcano in 1815 is generally
considered as the largest and most violent
volcanic event in recorded history. The
estimated loss of life in Sumbawa and nearby
Lombok are about 92,000 and the volume
of the erupted tephra has been estimated to
be about 150 km3 (Stothers, 1984; Self et
al., 1984; Sigurdsson and Carey, 1989). The
ash fall was recorded at least 1,300 km from
the source and the sound of the explosions
was heard to 2,600 km in distance. A region
extending up to 600 km west of the volcano
was plunged into darkness up to three
days. Stothers (1984) noted that tsunami of
20
0
40
60
kilometers
FLORES SEA
o
8 S
MT. TAMBORA
Madang Island
Sutodo Island
Kawinda
Sangiang Island
MT. SANGIANG
Moyo Island
M
Panjang Island
Alas
BA
W
A
BA
Y
SUMBAWA BESAR
SANGGAR BAY
Pekot
Kare
Sanggar
BIMA
Liang Island
SA
LE
Ngall Island H B
BIMA BAY
SU
DOMPU
AY
Nungga
Rakit Island
Taliwang
Jompong
Jereweh
o
9 S
INDIAN OCEAN
o
117 E
o
118 E
o
119 E
Figure 1. Locality map of Tambora Volcano in Sumbawa Island occupying most of the Sanggar peninsula
northern part of Sumbawa Island.
66
Effects of the 1815 Tambora Eruption to the Atmosphere and Climate (I. S. Sutawidjaja)
EJECTA OF 1815: VOLUMES
There are six layers could be distinguished
surrounding the volcano and the volumes
of the whole layers have been calculated;
the lowest consisting of phreatomagmatic
ash fall as the first product of the 1815
Tambora eruptive sequence is a gray, silty to
sandy ash fall layer, which was distributed
to the west of the volcano. It is 1-10 cm
thick on the western flank of Tambora and
eastern of Moyo Island and the volume of
this layer is 0,09 km3. The second layer is a
plinian tephra fall, a pale-gray-green Plinian
pumice fall deposit overlies the first layer
and extends over a wide area to the west
of Tambora. The layer is typically 10 to 30
cm thick on the slopes of the volcano and
has a volume of 1.18 km3. The third layer
is a tephra fall containing sandy to silty
pumice ash fall. The contact between the
two layers is sharp at proximal sites but
becomes increasingly gradational at sites
more than 50 km from the source. The
unusual dispersal of this ash both to the east
and west of Tambora may be a reflection
of plume dispersal in both high- and lowaltitude winds with the opposite polarity.
The volume of the third layer is 0.32 km3.
The fourth layer is a Plinian tephra fall as
the coarsest and most extensive of all the
early fall deposits from the 1815 Tambora
activity. The thickness of this layer is in
excess of 20 cm over the entire western
flank of Tambora, and the isopach of the
fall deposit is strongly symmetrical to the
volcano, elongated to the west. Closer to
the volcano, however, the thickness remains
relatively constant in the range of 25 to 30
cm and the volume of the deposit is about
3.02 km3. In these areas the pumice fall is
overlain by a surge deposit (Figure 2), and
Meter
4
Surface
Pyroclastic flow
1 - 4 meters
April 10 - 11
Pyroclastic surge
April 10
Plinian pumice fall
April 10
Phreatomagmatic ash fall
April 5 - 10
Plinian pumice fall
April 5
Phreatomagmatic ash fall
Pre-April 5
3
2
1
Basement rock
0
Figure 2. Pyroclastic stratigraphy of the 1815 Tambora eruptive products at Tambora village. Dates to the right of
the stratigraphic column indicate the inferred timing of the different eruptive phases based on historical reports.
67
Majalah Geologi Indonesia, Vol. 26 No. 2 Agustus 2011: 65-71
it is believed that here the pumice fall has
been eroded during passage of the surge
(Sutawidjaja et al, 2006).
Volumes of the four early tephra deposits
of the 1815 eruptive sequence have been
determined from a combination of isopach
maps and an extrapolation technique
proposed by Sigurdsson (1989). Plots of
isopach area versus isopach thickness were
constructed for each of the fall layers. On
plots of this type, tephra fall data can usually
be subdivided into two linear segments
(Sigurdsson, 1989) and the volume of a
deposit can be found by integrating the area
under the lines between two preselected
thickness limits. For the Tambora deposits,
the upper line segment has been adjusted so
that the slope is the same as a line used by
Wilson (1980) to calculate the volume of
Taupo ultra-Plinian layer. This line when
extrapolated to a thickness of 1 micron
yielded the same volume as that determined
independently for the Taupo deposit by
crystal-glass fractionation calculations
(Wilson, 1980). The volume of the Tambora
fall deposits were calculated with a lower
integration thickness limit of one micron
and an upper thickness limit based on
proximal thickness measurements. Because
it was not possible to subdivide the first and
third layers at all localities, especially in the
distal sections, only the bulk volume of the
complete sequences has been calculated.
With the exception of the first layer, about
70% of the volume of the fall deposits lies
outside of the mapped area (Figure 3). The
total volume of tephra deposited during
the first through the fourth events was 4.6
km3 (DRE).
The large fragments of pumice thus are
confined to the surrounding areas, while
the finer ash particles were transported
over a large area of the eastern Indonesia
by the wind, which was primarily from the
Figure 3. Ash deposits of the 1815 Tambora eruptive products preserved at Nangamiro village. The thickness
of the outcrop is about 3 m.
68
Effects of the 1815 Tambora Eruption to the Atmosphere and Climate (I. S. Sutawidjaja)
E and NE during the days of the eruption.
Sigurdsson (1989) calculated that the
distribution of pyroclastic flows on the
slopes of Tambora was estimated in total
deposition area on land of 820 km2 and
874 km2 for pyroclastic flows and surges,
respectively, and all of the exposures show
that pyroclastic flow deposits overlain surge
deposits. The flows exceed a total thickness
of 20 m, but the average is about 7 m,
indicating a minimum subaerial volume of
5.7 km3.
Junghuhn (in Stothers, 1984) calculated
the amount of material ejected by 1815
Tambora eruption, at 318 km3 of tephra fall
and pyroclastic flow deposits. The ash was
several meters thick close to the volcano; in
Lombok Island at 90 minutes distances from
Tambora, 70 cm thick; in Banyuwangi, East
Java, 210 minutes away from the volcano,
20 cm thick. Junghuhn draws a circle with a
radius of 210 minutes around Tambora and
assumes that the average thickness of the ash
within this circle was 60 cm. But because
the wind was mainly from the E, and the
finer material was there for largely carried
to the W (Lombok, Bali and Banyuwangi),
the assumption that sixty centimeters of ash
fell everywhere is too high for the areas for
the areas situated E, N, and S of Tambora.
Javasche Courant reported that the ash layer
was only 0,1 m thick in Bima, 60 km E of
the volcano; and only 0.03 m in Makassar,
270 km N of Tambora. According to Simkin
and Fiske (1983) Junghuhn’s calculation
therefore give apparently much too high.
It is more likely that the ash deposit with
an average thickness of 60 cm, only fell in
a rectangle of approximately 150 minutes
wide and 300 minutes long, with Tambora
located close to the eastern end of this
rectangle. Simkin and Fiske (1983) then
obtain: J = 2/3 x 150 x 300 x (1855 x 1855)
km3/109 = 103 km3. If it takes another 50%
for the material falling outside of it, which
definitely is high, then Simkin still obtains
150 km3.
EJECTA OF 1815: ITS ATMOSPHERIC
EFFECTS
Radiative forcing the climate system by
stratospheric aerosols depends on the
geographic dist aerosol distribution, altitude,
size distribution, and optical depth of the
aerosols, but tropospheric temperatures are
most strongly dependent on the total optical
depth (Lacis et al., 1992). This cloud injected
about 25 Mt of SO2 into the stratosphere, and
this SO2 immediately began to convert into
H2SO4 aerosols to the stratospheric aerosol
layer. Using a forcing in the model equivalent
to a global mean of about 0.15 based on
conditions appropriate for the Pinatubo
cloud yielded a model radiative forcing at
the tropopause of -4 W/m2 (Hansen et al.,
1992). This study shows that the temperature
anomaly after Tambora is about -0.4 to -0.7
degrees cooler than the average over a large
part of the Earth (Stothers et al., 1984).
Certainly, in terms of widespread impact, due
to its equatorial location, the early summer
date of eruption, and the resulting global
spread of the aerosol cloud, the peak optical
depth attained by the widespread aerosol
cloud, estimated to be >1.0 in northern
latitudes is six month after the eruption. The
Tambora aerosol cloud that enveloped the
Earth from the end of April 1815 to late 1816
(Figure 4) is the largest that followed by the
approximately 10 km3 Krakatau eruption
in late August 1883 (Rampino and Selt,
1982) consisting an estimated global aerosol
midvisible optical depth for Krakatau, which
was 0.14 in the late 1884 to early 1885.
This value is for the Krakatau aerosol layer
after more than 1 year’s dispersal (Tabel
1), and presumably much sedimentation of
particles, and peak optical depths may have
been considerably larger.
69
Majalah Geologi Indonesia, Vol. 26 No. 2 Agustus 2011: 65-71
a
Figure 4. Schematic diagram how the aerosol cloud and ash materials spread rapidly around the globe in about
three weeks and attained global coverage 1 year after the eruption caused the year without a summer(Courtesy
Discovery Channel).
Tabel 1. Comparison of Volcanic Aerosol ejected from the Volcanoes
Volcano
Location
Age
Aerosol
(Megaton)
Reference
Tambora
Indonesia
1815
40-60
Stothers, 1984
Krakatau
Indonesia
1883
30-50
Rampino and Self, 1982
El-Chichon
Mexico
1982
17
Rampino and Self, 1984
Pinatubo
Philippines
1991
15-20
CONCLUSIONS
The 1815 eruption of Tambora produced
about 318 km3 of dacitic magma, and this
is the largest volume in historical time.
Eruption columns rising above the vent
reached in excess of 33 to 43 km in altitude
and emplaced a giant umbrella cloud in the
middle to upper stratosphere that attained
a maximum dimension of over 1,000 km
in diameter, and this cloud injected about
70
Newhall and Punongbayan, 1996
25 Mt of SO2 into the stratosphere. The
aerosol cloud and ash materials spread
rapidly around the globe in about three
weeks and attained the global coverage
one year after the eruption caused the year
without a summer. Effect to the climate is
the cooling in the Northern Hemisphere as
large as -0.7oC over large parts of the Earth
in 1815-1816.
Global impact of Tambora eruption was
profound to the people in the Northern
Effects of the 1815 Tambora Eruption to the Atmosphere and Climate (I. S. Sutawidjaja)
Hemisphere that starved to death because
they lost their summer during the year, and
the volcanic aerosols changed the climate.
For the next large volcanic eruptions, these
aerosols will produce acid rain, endangering
skin and irritation of eyes.
ACKNOWLEDGMENTS
(1963), their stratospheric aerosols and climatic
impact. Quaternary Research, 18, p.127-143.
Rampino, M.R. and Self, S., 1984. The atmospheric
effects of El Chichon. Scientific American, 250,
p.48-57.
Self, S., Rampino, M., Newton, M., and Wolff, J.,
1984. Volcanological study of the great Tambora
eruption of 1815. Geology, 12, p.659-663.
This paper is compiled from the fieldwork data and
secondary data. The author thanks colleagues who
supported to write this paper.
Sigurdsson, H. and Carey, S., 1989. Plinian and
co-ignimbrite tephra fall from the 1815 eruption
of Tambora volcano. Bulletin of Vulcanology, 51,
p.243-270.
REFERENCES
Simkin, T. and Fiske, R.S., 1983. Krakatau 1883,
the volcanic eruption and its effects. Smithsonian
Institution Press, Washington D.C.
Hansen, J., Lacis, A., Ruedy, R., and Sato, M., 1992.
Potential climate impact of the Mount Pinatubo
eruption. Geophysical Research Letter, 19, p.215218.
Lacis, A., Hansen, J., and Sato, M., 1992, Climate
forcing by stratospheric aerosols. Geophysical
Research Letter, 19, p.1607-1610.
Newhall, C.G. and Punongbayan, R.S., 1996. Fire
and mud, eruptions and lahars of Mt. Pinatubo,
Philippines. University of Washington Press, Seattle
and London, 1126pp.
Rampino, M.R. and Self, S., 1982. Historic eruptions
of Tambora (1815), Krakatau (1883), and Agung
Stothers, R.B., 1984. The great Tambora eruption in
1815 and its aftermath. Science, 224, p.1191-1198.
Sutawidjaja, I.S., Sigurdsson, H., and Abrams, L.,
2006. Characterization of Volcanic Deposits and
Geoarchaeological Studies from the 1815 Eruption
of Tambora Volcano. Journal Geologi Indonesia,
1(1), p.49-57.
Wilson, L., 1980. Relationship between pressure,
volatile content, and ejecta velocity in three types
of volcanic explosions. Journal of Volcanology
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