The multitude of seracs gives the impression that the surface of the Perito Moreno glacier in Patagonia is covered with dragon scales -

© J. Ducker / Unsplash 2020

  • Human lifestyles do indeed accelerate the melting of glaciers, according to a study published by our partner The Conversation.

  • We can compare their disastrous fate by summoning, in a parable, that of the mythical dragons.

  • The analysis of this phenomenon was carried out by Olivier Dangles, Ecologist at the Institute for Research for Development (IRD).

As temperature records fall one after the other, we are more than ever concerned about the fate of glaciers, these emblematic victims of climate disturbances.

We are concerned about a sudden change in the color of the ice;

we try to cover them with white sheets to limit the effects of radiation;

we invite the French president to the bedside of the Mer de Glace ...

A fully justified concern: in half a century, glaciers around the world have lost 9,000 billion tonnes of ice;

this is equivalent to losing three times the volume of ice contained in the European Alps each year.

Yet there was a time, not so long ago, when glaciers inspired more awe.

Until the end of the Little Ice Age (∼1300-1860), the inhabitants of the valleys of the Alps regularly complained to the civil authorities about the damage they caused to crops and homes.

Back then, glaciers were compared to dragons clinging to cliffs, jaws open, winding through narrow valleys and threatening to descend upon villages.

Imaginative illustration of the Mer de Glace in the form of a dragon, by HG Willink (1892) © Henry George Willink

Dragons and glaciers actually have a lot in common in their "dealings" with humans.

And, beyond the anecdote, the parable of the dragons underlines the need to apprehend the predicted disappearance of glaciers in a transdisciplinary way, to bring together physical, ecological and philosophical sciences.

Scheduled shutdown

You have to get used to the idea.

After having used in recent decades the words "retreat", "retreat", or even "decrease" to describe the dynamics of glaciers, we must now explore a new lexical field: that of "extinction".

This process has already started in many parts of the world, especially in the tropical mountains, where small glaciers located at the ice limit altitude (between 4,800 and 5,000 meters in the Ecuadorian Andes) have already completely disappeared.

Likewise, the mythical glaciers of Kilimanjaro (Tanzania) or Puncak Jaya (Indonesia) will have completely disappeared within ten years.

A few centuries after the extinction of the last dragons, the glaciers will also disappear, struck down by humans and the disastrous consequences of their lifestyles.

Black ice

On the physical level, glaciers are, like dragons, immense living and mobile masses, often covered with "seracs", large blocks of billed ice, shaped like scales.

Composed of zones of accumulation, transport and ablation of ice, their survival is threatened when their mass balance is in deficit, that is to say that the accumulation of ice is no longer sufficient to compensate for its ablation.

In many parts of the world, the extinction of glaciers is accelerated by the blackening of the ice.

This phenomenon is caused by the deposition of black carbon contained in soot particles emitted during incomplete combustion, caused by gasoline engines, power plants or even fires, sometimes several hundred kilometers from glaciers.

Dust deposit and crevasse filled with water on a glacier of the Antisana volcano, in Ecuador © Olivier Dangles / IRD, CC BY-NC-ND

Having less reflective power than virgin ice, and a greater capacity to absorb solar energy, this blackening accelerates the melting of the ice.

In certain places, especially flat areas, these particles accumulate, forming real holes, cryoconites, colonized by biofilms, these communities of microorganisms whose thermogenic metabolism accentuates melting.

The role of these cryoconites in the process of glacial extinction is still little known;

but like the "draconites", these magic stones coveted by men and contained in the heads of dragons, probably at the origin of their disappearance, they could prove to be one of the weak points of glaciers.

Cryoconites on the surface of glacier 12 of the Antisana volcano (4900 m), in Ecuador © Olivier Dangles / IRD, CC BY-NC-ND

"Hic sunt dracones"

What are the consequences of the extinction of glaciers for biodiversity?

Glaciers play a major role in the genesis and maintenance of a remarkable diversity - animal and plant species, aquatic and terrestrial, some of which are endemic to periglacial areas, such as several species of aquatic flies.

In particular, glaciers provide water and mineral salts essential to life and generate heterogeneous and unstable environmental conditions favorable to the coexistence of species.

In recent years, scientists have also discovered that life is abundant on the very surface of the glaciers: viruses, yeasts, bacteria, algae, tardigrades, springtails, tiny crustaceans and insects, the largest representative of which is… a dragon.

On the glaciers of the extreme south of the Andes, the Patagonian dragon (

Andiperla willinki

), a 2 cm long stonefly, performs its entire life cycle in the glacial matrix, the larva living in water and the adult on the ice surface or in small crevices.

The Patagonian dragon (Andiperla willinki) - here a nymph - is a species of insect of the order Plecoptera (family Gripopterygidae) subservient to the glaciers of the extreme south of the Andes cordillera (between the parallels 46º and 56º South ) © Wikipedia commons, CC BY-NC-SA

This cryobiodiversity has developed an incredible arsenal of physiological innovations to adapt to life on ice, comparable to certain magical powers of dragons: resistance to extreme temperatures (-272 ° C), to strong UV radiation or even to the sidereal void.

If this biodiversity begins to be better described in temperate regions, this is not the case for tropical glaciers which remain, for the most part, unknown lands;

territories where dragons live, “Hic sunt dracones” as the medieval maps mentioned.

It is probable that this cryobiodiversity will disappear before having revealed all its secrets.

A whole spiritual world

If glaciologists and ecologists have been writing for several decades the chronicle of an announced death of glaciers, the human sciences have remained more discreet on the subject.

But, like the dragons feared by the inhabitants of the Alps, myths and beliefs related to glaciers are widespread all over the world.

In Peru for example, hundreds of pilgrims each year visit the sacred glaciers (or what remains of them) in the Cuzco region during the religious festival of Quyllurit'i.

Glaciers have become powerful cultural symbols, linked to the philosophical and moral dimensions of climate change.

Beyond the effects on water supply, human and animal food, glacial extinction will have important social consequences on mountain communities, including in terms of cultural identity, spirituality, aesthetics or even leisure.

Anthropological studies have also suggested that the loss of the glacier can affect community and individual identities, subjective understandings of the human / nature relationship or even lead to a general feeling of insecurity or eco-anxiety.

The frozen summit of the Cotopaxi volcano (5900 m), in Ecuador.

Olivier Dangles / IRD, CC BY-NC-ND

For centuries, people have been fascinated by dragons and glaciers.

If, despite their disappearance, the former retain an important place in our cultures, what will be the physical, ecological and spiritual consequences of a life without ice?

As part of the

Life without Ice

research project 

, we seek to answer this question by proposing an integrative and transdisciplinary study of glacier extinction, and by favoring a science approach to sustainability.

This approach erases the boundaries between disciplines, promotes the mutual enrichment of different models of thinking and reasoning, combines facts and values, in order to build knowledge systems more suited to the challenges of climate change.

And if the glaciers were to disappear forever in a few centuries, we can always take comfort from the predictions of recognized scientists: global warming should lead to the rebirth of real dragons ...

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This analysis was written by Olivier Dangles, Ecologist at the Institute for Research for Development (IRD).

The original article was published on The Conversation website.

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