Large Volcanic Eruptions and Climate Change: Impact on Earth’s Environment and Life

AP PHOTO/AUSTRALIAN DEFENCE FORCE/POIS CHRISTOPHER SZUMLANSKI

In this photo released by the Australian Defense Force, debris from damaged buildings and scattered trees can be seen on Atata Island in Tonga, on January 28, 2022, following the eruption of Tonga’s underwater volcano Hunga Ha’apai which triggered a tsunami.

JAKARTA, KOMPAS — Greenhouse gas emissions caused by humans burning fossil fuels since the industrial revolution around 1850 have triggered modern climate change. Previously, climate change had occurred repeatedly with a cycle of 26 million to 33 million years due to volcanic eruptions, which then triggered an environmental crisis and mass extinction of living things.

The latest analysis published in the journal Earth-Science Reviews on Wednesday (11/10/2023) shows that large volcanic eruptions in the past have released large amounts of carbon dioxide into the Earth’s atmosphere. This phenomenon caused extreme greenhouse climate warming and almost wiped out life on the planet.

Significantly, this phenomenon occurs on average every 26 to 33 million years, which coincides with critical changes in the orbits of planets in the solar system that follow the same cyclical pattern. The last wave of volcanic eruptions studied occurred about 16 million years ago.

“Earth’s geological processes, which were thought to be largely determined by events within the planet, are actually controlled by astronomical cycles in the solar system and the Milky Way galaxy,” said Michael Rampino, a professor in New York University’s Department of Biology, who was the lead author. this paper.

The researchers, including Ken Caldeira of the Carnegie Institute for Science and Sedelia Rodriguez, a geologist at Barnard College, caution that their conclusions have nothing to do with 20th and 21st century climate change, which scientists say is driven by human activity. Repeated climate changes in the past were more caused by natural factors.

The researchers added that the analysis still supports the impact of carbon dioxide emissions on climate warming. The difference is, this time the carbon emissions that trigger global warming in the modern era are triggered by human activity.

Also read: The Toba eruption has had a major impact on life on Earth

KOMPAS/NIKSON SINAGA

The Toba Caldera Crossing Motorboat carried President Joko Widodo to cross from Ajibata Harbor to Samosir Regency, North Sumatra, Wednesday (2/2/2022). The President asked that development in the Lake Toba area be used to improve the community’s economy.

260 million years

Some of the new analyzes include high-quality radio-isotope dating (U-Pb zircon and 40Ar/39Ar) for Continental Flood-Basalt (CFB) eruptions, dating of widespread marine anoxia, recent dating of marine and non-marine extinction events, climate intervals hyperthermal, and the occurrence of Hg stratigraphic anomalies, as well as non-radiogenic Os-isotope anomalies as potential proxies for large-scale basaltic volcanism.

The CFB eruption was the largest series of volcanic eruptions on Earth with lava flows covering nearly half a million square miles. Some of these lava flows are on the seabed, but others appear on land, such as the Deccan Traps in India and the Ontong Java Plateau, a large oceanic plateau located in the southwest Pacific Ocean, north of the Solomon Islands.

Rampino and his team found that CFB eruptions often occur in conjunction with other deadly geological phenomena, explaining the greater impact of volcanic activity. At least 13 of 17 anoxic oceanic intervals are characterized by Hg stratigraphic anomalies, indicating eruptions occurred at the same time, and 5 anoxic intervals in the warm Cretaceous Period are correlated with marine Os-isotope ratios indicating potential hydrothermal activity.

Nine of the marine anoxic intervals so far correlate with the timing of marine extinction episodes, and eight of these anoxia or extinction events significantly correlate with the ages of CFB eruptions long ago.

Large volcanic eruptions in the past have released large amounts of carbon dioxide into the Earth’s atmosphere.

Meanwhile, seven of the marine extinction events and associated CFB volcanism occurred simultaneously with the extinction of non-marine vertebrates, thus supporting episodes of global volcanic climate disasters that destroyed marine and terrestrial environments.

Meanwhile, the connection of major geological events in the past with astronomy is proven by the similarity of the cycles of volcanism and extreme climate that lasted for millions of years with the known orbital cycles of the Earth in our solar system and in the Milky Way galaxy.

The authors found that the alignment between geological and astrophysical cycles is too close to be considered mere coincidence. They then theorized that the planet’s astronomical movements disrupted Earth’s internal geological machinery.

“This is an unexpected connection and suggests a convergence between astronomy and geology—events that occur on Earth occur in the context of our astronomical environment,” says Rampino.

Previously, in their study report in the journal Geoscience Frontiers in 2021, Rampino and his team found that major geological events in the past did not occur randomly over time. His research provides statistical evidence of major geological events—including volcanic activity and mass extinctions on land and sea—ranging 26 to 36 million years or an average of 27.5 million years.

RAMPINO DKK (GEOSCIENCE FRONTIERS, 2021)

A cycle of major geological events millions of years ago.

Toba eruption

Climatic-Volcanism Feedback and the Toba Eruption of Around 74.000 Years Ago

A wise man

Anthropologist Stanley H Ambrose from the University of Illinois proposed a “volcanic winter scenario” to explain the bottleneck in the modern human population in the period 71,000-60,000 years ago. By matching the year of the Toba eruption, Ambrose concluded that the volcanic eruption on the island of Sumatra was what caused the volcanic winter during that period.

In his article in the Journal of Human Evolution (1998), Ambrose wrote: “Famine caused by the Toba giant eruption and volcanic winter led to the emergence of a human population bottleneck in the late Pleistocene era. Six years of volcanic winter, followed by 1,000 years of cold temperatures, was the driest season in the Late Quaternary.”

The latest major volcanic eruption occurred in the Pacific Ocean when Tonga Hunga Ha’apai erupted in January 2022, triggering an increase in global temperatures. A research team at the University of Oxford estimates that this volcanic eruption could push the average global temperature rise above the limit of an increase of 1.5 degrees Celsius.

Also read: How Climate Change Worsens Air Quality

However, if you look at Rampino’s latest findings, the eruption of Mount Toba, let alone Tonga Hunga Ha’apai, is still much smaller than a series of major geological events in the past. According to Rampino, the most recent set of major geological events occurred about 7 million years ago, which suggests that the next major geological activity will occur more than 20 million years in the future.

2023-10-11 06:24:53
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