Why in NEWS
A new study presented at the 2025 Goldschmidt Conference in Prague warns that melting glaciers may lead to increased volcanic activity, especially in high-risk areas like West Antarctica where 100+ volcanoes lie beneath the ice.
Key Concepts & Terms
| Term | Explanation |
|---|---|
| Subglaciated Volcanoes | Volcanoes located beneath glaciers or ice sheets, common in Antarctica, Iceland |
| Glacial Unloading | A reduction in surface pressure due to ice melt, allowing magma to rise more easily |
| Ice Sheet | Massive glacial ice covering more than 50,000 sq. km, found in Greenland, Antarctica |
| Sulfuric Acid Aerosols | Tiny droplets in the stratosphere formed from volcanic sulfur dioxide, reflecting sunlight |
| Goldschmidt Conference | Premier annual event in geochemistry, hosted by the European Association of Geochemistry |
Key Findings of the Study
| Aspect | Details |
|---|---|
| Volcano Sensitivity | Ice melt reduces pressure over magma, increasing eruption risk |
| High-Risk Areas | West Antarctica (100+ volcanoes), Iceland, Russia, New Zealand, North America |
| Historical Evidence | Iceland’s deglaciation 15,000–10,000 years ago led to 30–50x higher eruptions |
| Climate Interplay | Climate-driven rain may also seep into volcanoes, altering eruption patterns |
Impact of Volcanic Eruptions on Climate
| Effect | Description |
|---|---|
| Cooling (Short-Term) | Ash + SO₂ block sunlight → temporary global cooling |
| Example | Mt. Pinatubo (1991) cooled N. Hemisphere by ~0.5°C for a year |
| Warming (Long-Term) | Frequent eruptions release CO₂, methane → accelerate glacier melt and warming |
Glaciers – A Quick Overview
| Feature | Details |
|---|---|
| Definition | Large mass of compressed snow and ice that moves under its own weight |
| Formation | Snow → firn → glacial ice (over centuries) |
| Types | Alpine glaciers, ice sheets, ice caps, icefields |
| Coverage | ~10% of Earth’s land surface (~15 million sq. km) |
| Sea Level Risk | Full melt = +60m sea level rise |
| Largest Glacier | Seller Glacier (Antarctica) |
| Longest Glacier | Bering Glacier (Alaska) |
| Blue Ice Appearance | Dense crystals scatter only blue light |
In a Nutshell
V.E.N.T. = Volcano–Eruption–Nature–Temperature
Glacier Vanishing can trigger Eruptions, which alter Nature and Temperature—creating a dangerous feedback loop.
Prelims Practice Questions
- Which of the following is a subglaciated volcanic region?
A. Andes Mountains
B. West Antarctica
C. Saharan Plateau
D. Amazon Basin - The term “glacial unloading” refers to:
A. Sudden glacial collapse
B. Reduction of pressure due to melting glaciers
C. Artificial removal of glacier ice
D. Glacier sedimentation - Which volcanic eruption is linked to global cooling in 1991?
A. Krakatoa
B. Eyjafjallajökull
C. Mt. Pinatubo
D. Mauna Loa
Mains Practice Questions
- How does glacial retreat influence global volcanic activity? Evaluate with examples. (GS1 – Geography)
- Discuss the feedback loop between volcanic eruptions and climate change. (GS3 – Environment)
Prelims Answer Key
| Qn | Answer | Explanation |
|---|---|---|
| 1 | B | West Antarctica hosts subglaciated volcanoes beneath its melting ice sheet |
| 2 | B | Glacial unloading is the loss of pressure on magma due to ice melting |
| 3 | C | Mt. Pinatubo eruption in 1991 led to measurable global cooling effects |
