What Is ‘Watermelon Snow’?

“Watermelon snow” is a term used to describe a red algae that form on glaciers and very large areas in nature covered with ice. The algae has been around forever, but scientists are just now realizing the effect it is having on glaciers around the world.

Most of the scientific world is convinced of the reality of climate change and climate warming. Reports of glaciers melting are nothing new. But scientists now believe the red algae could be speeding up the melting process and hastening the disappearance of glaciers.

The algae is caused by Chlamydomonas Nivalis algae. It thrives in cold water. Glaciers and large snowfields are perfect environments for the algae as they have some nutrients in them. The blooms come in the spring and summer even in the Arctic.  It can reappear every year and grow as time passes, scientists say.

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A long-term study on Alaska’s Harding ice field showed that the algae caused a sixth of the snow melt over a period of years. The scientists suggest that climate simulations – used to predict how fast glaciers will melt – should include data on these red algae, which is not currently being done.

The reddish or pink tint the algae gives the ice also absorbs the sun’s heat because it is darker, and that speeds up the melting process.  The melting could make algae grow even faster, starting a cycle of melting with problems that feed on each other.

The recent study did a lot of research, more than just looking at the red algae, They used microscopes and satellites in the research. The glaciers contain nitrogen and phosphorus, natural fertilizers, which could aid in algae growth. The growth then allows more sunlight to be absorbed and hastens the melting of the glaciers, scientists have suggested.

At the Harding Icefield in Alaska, they did experiments where they either added water or nutrients to various patches of snow.  Adding water led to 50 percent more algae growth. Adding fertilizer quadrupled the amount of algae, compared to areas that were left natural.

This experiment showed that they scientists hunch was correct. The reddish algae allow more sun in, and that makes the ice melt faster. The water released from the ice causes more nutrients to be released, which causes more algae to grow.

Watermelon Snow 2

Another experiment also added some insight to the melting glaciers. Fertilizer was added to some areas, which made the algae grow faster. In other areas, they used bleach to remove the algae. The areas with extra algae melted much faster than the areas where the algae had been removed. Over the 100-day period of the test, the areas where fertilizer was added were three times more likely to melt than other areas.

The scientists also used satellite images to see the impact of melting over the entire Harding Icefield. They found that algae had grown significantly in recent years. They estimated that the algae were responsible for 17 percent of the melting that has occurred. The rest of the melting was attributed to warmer temperatures.

The scientists got these results by changing the environment to see immediate effects. In the past, they have used long-term observation to make predictions.

Another study in the Arctic found the presence of red algae, or watermelon snow had reduced the snow’s reflective nature by 13 percent. The lower reflection would increase the rate of melting because more heat and more sunlight are absorbed.

They found the algae is most comfortable, and grows best, just below freezing where ice is often slush or in the process of melting. Another study in Greenland, that lasted five years, found dark tinges in the ice from a different kind of microbe. It wasn’t red algae, but scientists think other types of plant material like this could have the same effects.

It is clear then that the red algae is increasing the speed at which glaciers are melting, and they are melting.

Watermelon Snow 3

When Glacier National Park was founded in 1910 it had 150 glaciers. Today there are about 30.  Those that remain have also been reduced in size by a third in recent years. A National Geographic study predicted the glaciers there will be completely gone in 30 years.

The National Geographic study also noted changes around the world.  The  Sperry Glacier at Glacier National Park in particular, has shrunk from 800 acres to 250 acres since 1901.  The snows on Kilimanjaro have melted 80 percent since 1912.  Scientists believe glaciers in the Himalayas of India could completely disappear by 2035.  The arctic ice sheet itself has also decreased in thickness by 10 percent in the last 30 years.

In the Northern hemisphere the signs of spring are showing up nine days earler, on average, and fall is arriving 10 days later than it was 159 years ago.

Also, the sea level around the world has risen four to eight inches in the last 100 years. This happens because there is more fresh water being introduced into the oceans, and when it is warmed up it expands.  Scientists estimate it is rising a tenth of an inch per year, which is much faster than it had been for many centuries.

Scientists further believe that greenhouse gases are the main culprit when it comes to what is causing climate change. The levels of these gases being put into the air are gradually warming the temperature of the planet. To some extent, they also block the suns rays.

Most scientists and many studies have shown, that the earth is getting warmer and doing so at a rapid pace.  Most also believe human activity is a major factor, though this study shows that there may be some natural aspects as well.  Even so, if the temperature were not rising and melting some of the ice, it would not produce the algae that are speeding up the melting process.

Another culprit is ash from wildfires around the world that are landing on ice sheets in Greenland and other places. These give the ice a darker color, which also allows it to absorb heat from the sun just as the watermelon ice or red algae does. Scientists say this has been particularly true over the last 10 years in Greenland.

The famed Greenland Ice sheet holds billions of gallons of water that is frozen, but it is melting fast, relatively speaking. The ice in Antarctica is melting too. Scientists estimate the melting in those two areas has caused a half an inch rise in sea levels over the last 20 years.

While there is some melting in Antarctica, most of the melting is happening in the northern hemisphere. That is also where the most pollution is, scientists have shown.  Scientists have shown that ice in Greenland is melting five times faster than it was 100 years ago.

Antarctica has been fairly constant, but it has increased in the last decade. Greenland seems to be speeding up though. Last year it broke a 30-year record for ice melting.

The ice melting causes more red algae to bloom, which makes the melting go faster. Scientists are not sure how to stop the melting, but many believe we should cut back on man-made pollution which might slow the process.

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