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There exist no flora, and merely a handful of fauna: human beings seldom frequent this location. The massive ice formations in Greenland have always been viewed as frozen wastelands. Enormous ice masses where the environment for survival is incredibly challenging.

But now, it seems, we have been wrong. There is much more life on the glaciers than we thought.

Under the leadership of Professor Alexandre Anesio, a team of scientists from the Department of Environmental Science at Aarhus University have uncovered that the glaciers are abundant with organisms. These are microorganisms that have adjusted to living on the ice. Furthermore, the number of species is not limited to one or two. Instead, there are numerous thousands of distinct species.

"Alexandre Anesio states that a tiny pool of melted ice on a glacier could harbor around 4,000 distinct organisms. These organisms rely on bacteria, algae, viruses, and microscopic fungi for survival, forming a complete ecosystem that was previously unknown to us."

What do the microbes live on?

Throughout the last five decades, scientists have been consistently astonished by the resilience of life. Organisms have been discovered thriving several kilometers below the Earth's surface, where there is no sunlight or oxygen. Billions of microorganisms survive by "feeding" on minerals found in the bedrock.

Scientists demonstrated that survival is possible for organisms even in the space environment. In 2007, a group of European scientists positioned over 3,000 microscopic tardigrades (water bears) outside a satellite and dispatched them into orbit surrounding the planet. The orbit persisted for 10 days, following which the satellite descended back to Earth. A minimum of 68% of the microorganisms endured the vacuum and hazardous radiation in space.

Hence, it is possible that thriving life exists on glaciers as well. Considering the presence of sunlight, oxygen, and water, this shouldn't be shocking. However, scientists previously held the belief that the ice lacked adequate nutrients to support life, but this notion has been proven false.

There is nourishment. Just in incredibly small quantities, explains Alexandre Anesio.

Black algae

One of the foremost microorganisms on the ice that captured the researchers' attention is a tiny dark algae. The algae thrives on the ice surface and stains it black. The black algae holds an intrigue for the researchers for a specific reason.

"Once the ice turns darker, its reflective ability diminishes, making it arduous to bounce back sunlight. Rather, the ice absorbs the heat from the sun, initiating the melting process. As the ice melts more, the Earth's temperature escalates. Hence, the algae hold a crucial function in the phenomenon of global warming," stated Alexandre Anesio.

Over the last few years, the ice has progressively acquired greater areas of algae staining, which has resulted in a further acceleration of the ice melting. Alexandre Anesio's computation reveals that the algae are contributing to a 20% rise in ice melting.

The presence of algae on the ice predates the onset of global warming triggered by industrialization. Nevertheless, due to climate change, the Arctic experiences an increasingly earlier arrival of spring, leading to an extended period for the algae to propagate and proliferate.

"The algae propagate slightly each year. While journeying to Greenland, I now behold extensive regions where the ice is entirely dusky due to the algae," he declares.

Looking for an algaecide

Alexandre Anesio and his associates are dedicating significant time to the dark algae as they aim to determine if there is a means to decelerate the growth of the algae.

There exists a harmony in most ecosystems - a form of stability - as the different organisms maintain mutual control. Therefore, Alexandre Anesio aims to gain further understanding of the correlation among the diverse microbes.

"The diverse microorganisms present on the ice interact with each other. Certain organisms provide nourishment for others. Tiny viral agents assault and feed on microbes. It is our hypothesis that select fungal spores may ingest the dark algae. Such is our pursuit," he affirms.

Notwithstanding, he emphasizes that discovering a method to restrain the proliferation of algae will not resolve climate change, although it may decelerate its progression.

The same pigment as in black tea

Algae exists practically everywhere. It can be found in oceans, in ponds, on trees and stones, and even as tiny particles in the atmosphere. The majority of algae are green. Similar to plants and trees, they derive their green hue from chlorophyll, a molecule that facilitates photosynthesis.

But it's different for the black algae.

"Since the algae dwell on the ice, they receive a constant barrage of sunlight and radiation. In order to safeguard themselves, they generate a significant amount of black pigment. Interestingly, this pigment is identical to that found in black tea. The pigment creates a shielding layer around the algae, shielding the chlorophyll molecules from the hazardous radiation," remarks Alexandre Anesio.

As the pigment soaks up the sun's radiation, it produces warmth, which causes the ice encasing the algae to thaw. Surprisingly, this is advantageous to the algae, since they rely on the water and micronutrients within the ice to sustain themselves.

And they can only use the water when it is liquid.

NASA also has an eye on his research

The investigation by Alexandre Anesio on life in icy environments bears significant importance in advancing our comprehension of climate change. Notably, NASA is closely monitoring the outcomes of his research, as they may prove pivotal in the quest for detecting life beyond Earth.

"NASA has contacted us multiple times as we study life residing in an extremely hostile location on Earth. If life can prosper in and beneath the ice, there is a likelihood of discovering life in the ice on Jupiter's, Saturn's, or Mars' ice moons," he explains.

Before NASA sent their Perseverance rover to Mars, they even invited Alexandre Anesio to a meeting.

"Their concern was about the possibility of the rover carrying Earth's microbes with it, which could potentially survive on Mars and contaminate the samples to be collected. Therefore, they aimed to ascertain the conditions under which life can endure, and what limits define the boundaries for life."

Can give an indication of what they should look for

NASA's interest in studying life in ice is due to the absence of liquid water on any other celestial bodies in our solar system. Despite this, we have discovered an abundance of ice.

Nonetheless, indications point to the existence of subsurface liquid oceans on Saturn's moon Enceladus and Jupiter's moon Europa, despite their frozen surfaces. Liquid water is one of the essential elements for life, as we understand it.

Hence, NASA and other space organizations hold great interest in gaining additional knowledge about the forms of life that can thrive on and beneath the ice. This is because the organisms that resemble those found in Greenland are likely to be the ones sought after on the icy moons.

"Similar to us, their interest lies in understanding the functionality of microorganisms present on the ice. What quantity and what type of nutrition do they require? Additionally, they seek to comprehend the workings of the ecosystem these microorganisms inhabit. These are the inquiries we aim to resolve in the times ahead," remarked Alexandre Anesio.