Something Disturbing Is Taking Over Greenland’s Ice

Bright Side

Something strange is happening in Greenland, and it’s pretty concerning. The ice there is being covered by dark patches, and it’s not just regular dirt—this stuff is alive! Scientists have discovered that algae are spreading across the ice, and because they're dark, they absorb more sunlight. This causes the ice to melt faster, which could make sea levels rise even quicker. The more the ice melts, the more the algae spread, and it's creating a scary cycle. If this keeps happening, it could have big effects on our planet’s climate.

Transcript

00:00These dark patches on Greenland's ice sheet aren't just any old stains.

00:06Every summer, the ice, which is usually bright white, turns murky gray in certain areas.

00:12This so-called dark zone was a huge mystery for a long time,

00:16until some studies discovered that this weird transformation was connected to the odd appearance

00:21of red, green, and brown-colored algae. The scariest part is that this algae bloom keeps

00:28growing. The dark zone is getting darker, and terrifying microbes might start appearing.

00:34Now, the rest of the world should be concerned.

00:37The Greenland ice sheet is like a massive ice blanket that covers around 80% of the island.

00:43It's so thick that it holds about 8% of the world's freshwater ice. For most of the year,

00:49the ice looks like a giant untouched white sheet stretching over the land.

00:53But when summer rolls around and temperatures start to rise, things begin to change.

00:58The ice melts, revealing rocky areas along the coast. And as you move further inland,

01:04that once smooth white ice becomes darker. This is the dark zone, and it covers an area

01:10of around 248 miles in length and 62 miles at its widest point. This weird phenomenon happens

01:18basically for two reasons. The first one is black carbon. Just like dust that builds up on your

01:24bookshelf, the ice in Greenland has the same issue. The wind carries a mix of dust and soot to this icy

01:31area. But unlike your bookshelf, you can't just wipe it off with a cloth. In Greenland's case,

01:37this dirty mix settles on the ice and sticks around for thousands of years.

01:41So, the dark zone is basically covered in a fine layer of dust that's built up over time. Back in

01:512014, researchers analyzed this dirty mix and found that the darker ice areas were filled with black

01:58carbon. This black carbon didn't just appear out of thin air. Well, actually, it sort of did.

02:04Scientists believe it mostly comes from smoke produced by wildfires in northern Canada and Alaska

02:10somewhere in the past. As you might guess, black carbon is black, which is why it makes the ice look

02:16darker. Now, the second big reason for the Greenland ice sheet's summer makeover has to do with those

02:25algae we mentioned earlier. We're mostly talking about two types of it. The Ancelonoma alaskana and the

02:32Ancelonoma norden scholdii. Both of them love cold water regions. During winter, they stay in a dormant

02:39state deep within the ice. But when spring comes, they start to slowly migrate to the surface.

02:46By the time summer hits, they're ready to bloom and soak up nearly 24 hours of sunlight each day for

02:52photosynthesis and growth. Normally, these algae are green. But when exposed to sunlight, they turn

02:59brown as a natural way to protect themselves from harmful ultraviolet rays. And this color change

03:05is also what makes the ice in Greenland look darker.

03:11So far, this has been normal behavior. What's really alarming is that these algae blooms are

03:16getting bigger and bigger every year. This happens because they thrive on phosphorus,

03:22a nutrient that's plentiful out there and comes from a mineral called hydroxyl lapatite.

03:27This mineral is found in a type of rock that breaks down into tiny dust particles, which are then blown

03:34across the ice by the wind. As the climate gets warmer, the rocks dry out more and stronger winds

03:40carry more dust. More dust means more phosphorus, leading to more algae growth. See? It is a cycle

03:48and it keeps getting worse every year. Studying this is crucial to understanding why the dark zone

03:55keeps getting bigger. From the year 2000 to 2012, its size increased by 12%.

04:02But you might be wondering, why should we care? After all, it's just ice getting darker, right?

04:10Well, not exactly. Think about how you can't stand wearing black clothes on a hot sunny day.

04:17They soak up the heat and make you feel even hotter. That's because darker surfaces absorb more sunlight.

04:22The same thing happens to ice. Together, dust, black carbon, and algae blooms are responsible for about

04:3070% of the variability in albedo on the Greenland ice sheet. Albedo is just a fancy word for how

04:37reflective a surface is. If you take two surfaces, one white and shiny and the other dark and rough,

04:44the white one will reflect a lot of light and heat, giving it a high albedo.

04:49The dark one, on the other hand, will absorb more light and heat, so it has a low albedo.

04:57During the summer, the Greenland ice sheet experiences a reduction in albedo.

05:03This means the ice absorbs more sunlight, and when ice absorbs more sunlight, it melts faster than it

05:08should. This is why understanding what's happening in the dark zone is so important. It helps predict how

05:15quickly the Greenland ice sheet is melting and how it can affect the rest of the world.

05:23Greenland's ice sheet is the second largest in the world, covering an area about the size of all the

05:29land in the United States east of the Mississippi River, and its huge mass of ice averages a thickness

05:35of 1.4 miles. Unfortunately, the ice loss has skyrocketed. Back in the 1990s, Greenland was losing

05:44about 25 billion tons of ice per year. Now, it's losing around 234 billion tons per year.

05:53That's nearly 10 times more ice melting away each year.

05:57According to NASA, if all of Greenland's ice sheet were to melt, it would increase global sea levels

06:05by about 24 feet. That could be catastrophic for coastal countries and cities around the world.

06:12The Netherlands could be submerged, the Bahamas could be almost completely wiped out,

06:17and many of the Philippines' islands would be at risk of disappearing.

06:21All of this may seem like a distant reality, and it is true that most scientists believe it would

06:28take several hundred or even thousands of years for the ice sheet to melt completely.

06:33But it is important to know that Greenland didn't always have this thick layer of ice.

06:39Very recently, researchers took a close look at some sediment from the bottom of a two-mile-deep

06:45ice core extracted from the center of Greenland. They found that the soil had traces of willow

06:51wood, insect parts, fungi, and even poppy seeds. So, these fossils are the first direct evidence

06:57that Greenland's ice sheet melted away in their recent geological past, around 400,000 years ago.

07:04At that time, Greenland was home to a green tundra landscape with insects and plants.

07:10This discovery is both fascinating and scary, because it shows that the ice sheet collapsed before

07:16and might be more fragile than scientists originally thought.

07:21There is another concern, too. A recent research collected meltwater from different spots on the

07:29Greenland ice sheet and found that the water samples were packed with hundreds and thousands

07:34of microbes. The concern is that they could be released into the ocean in the future.

07:39And some studies already suggest that areas near where a lot of glacial meltwater flows have a higher

07:45risk of viruses jumping to new hosts, like from animals to humans.

07:52Even though experts believe the chance of a doomsday virus coming from the glaciers is very small,

07:58it's still not zero. The truth is, we don't know much about the thousands of microbial species living on

08:05the surface of the ice, and there is simply not enough data to fully understand how dangerous these

08:11organisms might be. All of this might sound concerning, but we shouldn't panic just yet.

08:18There's still a lot we don't understand about what is darkening the Greenland ice sheet.

08:23We still need more detailed measurements of the relative abundance of dust, algae, and black carbon,

08:29as well as a better understanding of how these potentially dangerous microbes could affect our lives.

08:34The more we learn, the better we can predict what's going to happen and how we can prepare for it.

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