The cataclysmic eruption of Mount Tambora on Sumbawa Island, West Nusa Tenggara, lasted several months from April to July 1815.
The death toll was up to 250,000 in Tambora vicinity and around the globe as the eruptions caused bad weather, prolonged winter, devastated agriculture and led to famine.
The 210th anniversary of the Tambora eruption is a moment to contemplate, and to educate the public about volcanoes’ threats and their value to mankind.
Indonesia is home to 127 active volcanoes, which is about 13 percent of all active volcanoes in the world. We are sitting on two entangled rings of fire: The Circum-Pacific and the Circum-Mediterranean, two volcanic belts that knot the globe. Most of the volcanoes are beneath the ocean. There are thousands of underwater volcanoes in the Pacific Ocean, one of them was Mt. Krakatau, which emerged from the bottom of Sunda Strait.
Towering over Sumbawa Island, Tambora is “napping” peacefully now. In 1815, the eruption was rated 7 on the Volcanic Explosivity Index (VEI), VEI 8 being the highest. The eruption of Mt. Tambora was one of the most cataclysmic events in the history of mankind. Its eruption strength was 10 times more violent than the 1883 Krakatau eruption (VEI 6), and 100 times stronger than the eruption of Mount Vesuvius in Italy (VEI 5) in 79 AD.
Ash and aerosols injected into the stratosphere, blocking the sunlight and causing global cooling, reduced the average surface temperature by roughly 1 degree Celsius in just one year.
The following year, 1816, went down in history as “the year without a summer”. Harvests as far away as Europe and America failed. Famine and death were rampant in both continents.
Mt. Samalas (or old Rinjani) in adjacent Lombok Island erupted much earlier in 1257 with a catastrophic eruption. It spewed aerosol and sulfuric gas affecting the globe. The eruption, estimated to be similar to Tambora at VEI 7, possibly triggered or enhanced the following 100 years of the Little Ice Age.
The Samalas eruption sent sulfuric acid to both ends of the poles, contaminated air as far as London and killed up to 20,000 Londoners. The estimated amount of sulfate expelled into the stratosphere was around twice that of Tambora in 1815. The Mt. Samalas eruption is thought to have been the fiercest eruption in the last 5,000 years.
Civilizations and economies were transformed by the Tambora eruption. Napoleon Bonaparte’s defeat at Waterloo was said to have been caused by rain and mud caused by ash from the Tambora eruption that reached Europe. Another effect of the eruption was the death of horses and the destruction of carriages that led to the invention of the bicycle by Baron Van Draise. Literary works like the novel Frankenstein also mention the blood-red London sky of those days.
The earth would have no fresh water accumulation without mountains caused by volcanoes. Precipitation falls on the slopes of the mountains before seeping into the porous sediment layers, filtering until it is stored in the aquifer layer. Rivers spring from these mountains. We have at least 5,000 big rivers, enough for our potable water supply, irrigation, lakes and hydrokinetic power generation.
We would also not have as much food without volcanoes. Volcanic soil is very fertile. Its ashes are rich in essential minerals like phosphorus, potassium and magnesium. Thanks to this fertile soil, we enjoy the exquisite tastes of Java Arabica coffee, Gayo Arabica coffee, Sihobuk peanuts of Tarutung and more.
Volcanoes also provide sustainable energy in many forms: geothermal, rivers and valleys for hydropower, and fertile soil to grow biomass energy.
Indonesia is home to 40 percent of the world’s geothermal potential. The largest in the world, as well as the largest geothermal-generated electricity in the world, with utilization at 2,378 megawatts out of an identified potential of 23 gigawatts.
Interestingly, volcanic eruptions are cooling our planet. Ejected volcanic ash reaches the lower part of the stratosphere, partially blocking sunlight.
Decades-long global cooling was recorded as being caused by the eruption of Mt. Samalas in 1257.
More recent eruptions like Pinatubo (1991) also show a drop of earth temperature by 1.3 degrees Fahrenheit for three years. In terms of carbon dioxide emissions, volcanoes release less than 1 percent of the CO₂ released currently by human activities, according to the United States Geological Survey.
Volcanoes provide fertile soil for greenery, water retention and various materials for climate adaptation.
Magma that rushes up to the earth’s surface delivers valuable materials to the surface. The extreme heat of magma perfects the mineralization. Gold and silver veins augment quartz veins in the surrounding cooled magma rocks. Volcanoes supply plenty of clay and sand sediments, as well as gravel and boulders for humans to build cities.
Hundreds of temples and archaeological sites of ancient civilizations in our archipelago were excavated under several meters of volcanic ash, clay and sand. This indicates successive catastrophic events occurred throughout history.
The landscape of a conical volcano is magnificent, adorning the earth’s topography with cliffs, slopes, valleys and terraces. Geo-ecotourism in Java in particular, can be extended to reveal the hidden gems of many volcanoes. A single volcano can be admired from any and every angle, combining nature, culture and ancient civilization in a single geopark.
With such extraordinary assets, facing significant threats, the government should make thorough policies, laws, regulations and enforcement related to our volcanoes, particularly in regard to geospatial planning surrounding volcanoes, for water retention management, food security, sustainable energy, mining and risk mitigation. Academia needs to study and document more about volcanoes from many disciplines to enable us to live harmoniously with them.