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Climate change will lead to more 'green snow' in Antarctica

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This 'green snow' is found in warmer parts of the Antarctic, scientists think climate change will lead to more of it growing. Hear from Dr Matt Davey about his research.

Scientists from the University of Cambridge and British Antarctic Survey have been using satellites to map areas of 'green snow' in the Antarctic.

It's actually patches of millions of microscopic plants called algae growing across the surface of the snow.

They found that the algae blooms are an important part of the carbon cycle in Antarctica and are naturally fertilised by animal poo.

It's thought that the areas of green snow are likely to spread as global temperatures increase.

Image source, Matt Davey/University of Cambridge
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Animal poo helps the algae to grow!

The algae grows on existing snow turning it bright green, patches of this green snow can even be seen from space!

It grows in warmer areas, where the average temperatures are just above zero degrees Celsius.

The team found that the spread of the green snow is influenced by animal poo!

Marine birds and mammals' poo acts as a highly nutritious natural fertiliser which encourages algae growth.

Image source, Matt Davey/University of Cambridge
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Scientists lived in pods like this while they did their research

Over 60% of the algae patches were found within five kilometres of a penguin colony.

And other algae grew near birds' nesting sites.

Image source, Matt Davey/University of Cambridge
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The team used a combination of fieldwork and satellite technology to make a map of where the algae is growing

Dr Matt Davey is from the University of Cambridge, he said this green snow is a "significant advancement in our understanding of land-based life on Antarctica and how it might change as the planet warms."

He added: "Snow algae are a key component of the continent's ability to capture carbon dioxide from the atmosphere through photosynthesis."

What is photosynthesis?

This is the process in which plants and algae generate their own energy, using sunlight to capture carbon dioxide from the atmosphere and release oxygen.

"We identified 1679 separate blooms of green algae on the snow surface, which together covered an area of 1.9 km2, equating to a carbon sink of around 479 tonnes per year" said Davey.

That is the same amount of carbon produced by about 875,000 average petrol car journeys in the UK.

There are also patches of orange and red algae growing on the snow which will be examined in future studies.

Although rising temperatures mean snow in the Antarctic is melting in lower lying areas the scientists think the amount of snow algae will actually increase as the planet warms because it will still grow on higher ground.