Glacial Lake Outbursts | Collapsing Permafrost | Feedback loops
Crumbling mountains | Atlantic Meridional Overturning Current
The key role of ice in global warming
The cause and effect relationship between ice and global warming extends far beyond melting ice caps and shrinking polar bear habitat. From Greenland’s ice sheets to Siberian permafrost thaw to collapsing Alpine glaciers, there is virtually nowhere on the Earth the planet’s vast reserves of frozen water aren’t melting fast. For better or worse, the consequences of this phenomenon are not obvious on a global scale. This page covers several interrelated topics that don’t penetrate public awareness.
- Albedo reflectivity feedback
- P ermafrost collapse \ methane feedback
- Glacier Lake Outburst Floods
- Melting ice “glue” causing Alpine rock falls
- The Third Pole and the threat to Asian fresh water supply
- The affect of fresh water melt on the Atlantic Meridional Overturning Circulation (AMOC)
Polar Ice Formations: How they affect global climate
Fundamentals: Location, location, location
A key factor in global ice melting patterns is an often overlooked matter of basic geography.
- The North Pole is frozen ocean (Sea Ice)
- The South Pole is a massive land continent covered by trillions of tons of snow pack and ice (land ice, sea ice, shelf ice).
For the purposes of climate science, the three categories of ice are dictated by where ice is located.
SEA ICE (salt water): Disappearing rapidly in the Arctic and more sporadically in the Antarctic since 2016. sea ice floats and does not raise sea levels when it melts. It does affect weather patterns and the Albedo reflectivity feedback. ANTARCTICA: Extreme Antarctic sea ice variations have contributed to ocean current destabilization, which in turn affects weather patterns.
LAND ICE (fresh water): Trillions of tons of land ice on Greenland, Alaska, Iceland and the Antarctic continent contain enough fresh water to raise sea levels several meters..
SHELF ICE: Hybrid formations are critical to braking the flow of land ice into the ocean. The “front” of an ice shelf rests on land and the “back” floats in the ocean, subjecting it to accelerated warming. (See middle column)
The Doomsday Ice Shelf
The Twaites Glacier ice shelf on the West Antarctic peninsula is known as the “Doomsday Glacier.” It is expected to break up in the very near future. If it collapsed completely, it would raise global sea levels about two feet. Equally alarming, the Thwaites and other coastal shelves act as a brake on the advancing land ice on the continent behind them.
Albedo Reflectivity Feedback
ALBEDO REFLECTIVITY FEEDBACK LOOP: The mechanism of this relentless positive feedback cycle is easy to understand. When sunlight radiates on Ice and snow, the heat energy is reflected back into space. But when sea ice disappears, the heat energy is absorbed directly into dark ocean water, heating it. The warm ocean melts more ice, which then opens more water to the heat energy. Repeat. See other climate feedbacks..
“Third pole” ice melt threatens water supplies for 2 billion humans
The Hindu Kush Himalaya region supplies water to major river systems including the Indus, Ganges, Brahmaputra, Yangtze, Yellow River, Mekong and Amu Darya
The Himalayan ecosphere is changing before our eyes
DISAPPEARING ICE IN HIMALAYAN GLACIERS IS ACCELERATING A MAMMOTH WATER CRISIS
The Himalayas store more frozen water than any other source except the Arctic and Antarctic ice sheets. These high mountain glaciers feed rivers that sustain nearly one-fourth of the world’s population. For thousands of years, billions of humans downstream have relied on a predictable seasonal release of glacial water into rivers, but global warming has quickly changed the scenario. With some glaciers losing ice mass at four times the normal rate, the region faces a convergence of environmental, health, and geopolitical crises.
TWO PRONGED CRISIS: Near term, accelerated melting can produce too much water too quickly—including devastating Glacial Lake Outburst Floods (GLOFs – see right column). Longer term, continued glacier shrinkage means less dependable water during the dry season, when millions of people most need it. At some point, the outcome is the end of this water source.
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Glacial Lake Outburst Floods
While the catastrophic Nepal event that killed 10,000 in
August 2026 is a major GLOF event, is it far from an isolated occurrence. In 2023, the South Lhonak GLOF in Sikkim, India, killed dozens of people and caused extensive infrastructure damage.
HOW GLOFs HAPPEN: As glaciers retreat, meltwater accumulates in lakes behind unstable moraine or ice dams. These lakes can grow rapidly. A landslide, avalanche, ice collapse, earthquake or extreme rainfall can suddenly displace water or breach the dam:
These floods can travel rapidly down narrow valleys, carrying boulders, mud, trees and enormous quantities of sediment.
About 200 glacial lakes across the Hindu Kush Himalaya are considered dangerous, and projects that GLOF risk will increase substantially as warming continues
Destabilized mountain structure
DESTABILIZATION: ROCK FALLS The Himalayan climate threat is more complex than melting glaciers alone. It involves a destabilization of the entire high-mountain environment. Rock formations are held together by ice, which functions more of less as a “glue” to hold rock and soil in place. When ice that has previously remained frozen year round melts and refreezes, water to penetrates cracks previously held together by frozen soil. The entire mountain slope is structurally compromised. At some point, the side of the mountain collapses in a rock fall or landslide.
Glacier retreat also removes the ice that can buttress mountain slopes.
Global consequences of rapid Permafrost thaw
A relentless methane feedback loop and transformed terrain
As the Arctic warms four times faster than the rest of the planet, the vast tundra plains of the north are thawing rapidly. While relatively few people think much about these unseen forces, the ramifications are global and implacable.
Methane Plumes: Melting permafrost is causing release of CO2 and CH4 trapped beneath once frozen surface. This is one cause for the rapid uptick in atmospheric methane. Siberian levels of CH4 emissions have doubled in ten years.
Infrastructure Collapse: Biblical savior Joshua ben Joseph recommended not building your house on sand, but he should have also mentioned not to build on permafrost. In Alaska, Siberia and northern Canada, buildings, highways and pipelines are falling down and into the sea. Humans constructed these artifacts under the assumption that the land would stay solid, but it is NOT staying solid. As the ground sinks, humanity’s limitations are exposed. The situation is worse in coastal communities as increased water temperatures reduce protective ice and allow waves to wreck permafrost bluffs and increase erosion.
Megaslump Craters: These massive blowholes are blasting out all over, transforming Arctic terrain into a spooky landscape called Thermokarst. These unsettling and often very large craters (also known as thaw slumps) are formed as once-trapped methane escapes the permafrost that once trapped it below. Megaslumps and the starkly strange thermokarst terrrain that accompanies them are not new, but they are multiplying as the tundra transforms. Sometimes a megaslump starts with a small soil collapse, other times there is a blowout when pressure grows too great. Arctic scientists now videotape footage of grassland wobbling as the substrata becomes less solid and scenes of lighting escaping methane as it escapes from once frozen ponds.
Microbes beneath the tundra: Pathogens have already been released:
Permanently frozen environments are natural reservoirs for microorganisms, including viruses, bacteria and humans pathogens. It is not currently considered likely that dangerous microbes such as smallpox are about to be released, but there is no question that dormant viruses will be released as the Arctic continues to heat up. The region is warming twice as fast as the rest of the planet. Which is warming very fast.
In 2015, researchers from Aix-Marseille University isolated two large DNA viruses in Siberia frozen for 30,000 years in ancient permafrost. They were not a threat to humans.
There was a well-documented anthrax outbreak in 2016 in Siberia. It killed thousands of reindeer. The cause of the outbreak is attributed to the activation of spores due to a permafrost thaw, accelerated during the summer heat wave of that year.
Powerful Methane Feedback Loop as Arctic tundra thaws
- Permafrost thaws, releasing greenhouse gases (CO2 , CH4).
- GHG’s trap heat in the atmosphere, increasing surface temperatures
- Permafrost melts faster, releasing more CH4.
Nature has a way of pointing out the hubris of human endeavor.
As once frozen Arctic ponds melt, flammable methane lurks beneath the surface.
Greenland and Iceland: Unexpected forces at work
The Hindu Kush Himalaya supplies water to major river systems including the Indus, Ganges, Brahmaputra, Yangtze, Yellow River, Mekong and Amu Darya
As massive quantities of fresh water enter the North Atlantic, things are changing quickly
1. THE ADDITION OF MASSIVE AMOUNTS OF FRESH WATER INTO THE NORTH ATLANTIC IS SLOWING DOWN THE GULF STREAM (AMOC)
The Gulf Stream is the best known component of the global ocean current known as the Atlantic Meridional Overturning Circulation (AMOC). This massive current is responsible for a major component of planetary weather and moderates Northern Europe’s climate (see middle column for more).
2. THE LAND MASS OF BOTH ISLANDS IS RISING AS THEY SHED THE WEIGHT OF ICE CAPS
There is no question that the addition of two mile thick melting ice caps into the ocean is raising sea levels. There is a range of projections regarding how quickly this process is taking place, but there is no doubt that it is gaining speed. Sea level rise is about double as it was in 1993.
But there is a less obvious effect as well. As the ice sheets melt and flow into the North Atlantic, the land beneath is lifting up. This paradoxical scenario, in that these two land masses will experience less net sea level rise that other coastal areas.
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Slowing the Atlantic Current
Melting of the Greenland Ice Sheet weakens the Atlantic Meridional Overturning Circulation (AMOC) by adding large quantities of fresh water to the North Atlantic. The system is currently the weakest it’s been in more than 1,000 years, having lost 10% to 20% of its strength due to climate change.
The basics of the mechanism are straightforward, but the magnitude of the effect is being actively studied. Most research indicates that the AMOC is already slowing.
The AMOC is essentially a huge ocean conveyor that distributes heat from Tropical regions to the north. When the current slows, it transports less heat to Northern Europe.
HOW IT WORKS: Warm, salty surface water moves northward through the Atlantic. In the subpolar North Atlantic and Nordic Seas, some of this water cools, becomes dense and sinks, forming deep water that flows southward. That sinking is the primary engine driving the overturning circulation.
Greenland’s ice sheet is freshwater stored on land. When it melts and reaches the ocean, it changes the salinity of the North Atlantic:
Arctic islands land mass lifting
As the miles thick ice caps that over Greenland and Iceland melt and shrink into the ocean, the land beneath is rebounding as the burden eases. The seas around them may actually appear to be lower when compared to the global inundations that are happening around the rest of the planet. For these two islands
Greenland’s ice sheet currently accounts for about 20% of global sea level rise. meaning seas may fall even as the meltwater causes them to rise elsewhere. A new study shows that in Greenland—whose rapidly melting ice sheet accounts for about one-fifth of current sea level rise—this paradox will mean expanding coastlines, dried-up fjords, and future complications.