Antarctica's pretty pink snow

2020-06-28李胜文

疯狂英语·新悦读 2020年6期

难词探意

1. drench /drentʃ/ v. 使湿透

2. massacre /'mæsəkə(r)/ n. 屠杀

3. algae /'ælɡiː/ n. 海藻；藻

A few weeks ago, scientists at Ukraine's Vernadsky Research Base in Antarctica awoke to find their usually white surroundsdrenchedin a shocking blood-red.

From the gory-looking images, you could be forgiven for wondering if there had been some sort of horror-movie-style penguin massacre.The good news is that the real cause is far less dramatic; unfortunately, it still has bad influences.

Marine ecologist Andrey Zotov from the National Academy of Sciences of Ukraine, captured these images.

“The snow had changed its color because of the tiny seaweed with a red carotene layer known as Chlamydomonas nivalis (雪地衣藻),” said the National Antarctic Scientific Centre of Ukraine in a Facebook post.

These microscopic greenalgae(we'll get to why they look red in a moment), a type of singlecellular seaweed, are common in all icy and snowy regions of Earth, from the arctic to alpine regions.

They hibernate during the winter, but once the sunlight warms enough to soften their crystallised world, the algae spring awake, making use of the meltwater and sunlight to rapidly bloom.

“The algae need liquid water in order to bloom,” University of Leeds microbiologist Steffi Lutz told Gizmodo in 2016. The algal blooms contribute to climate change, the centre stated.

A study in 2016 showed that snow algal blooms can decrease the amount of light reflected from the snow (also know as albedo) by up to 13 percent across one melt season in the Arctic.

“This will result in higher melt rates,” the researchers wrote.

In 2017 environmental scientists calculated that microbial communities contributed to over a sixth of the snowmelt where they were present in Alaskan icefields. Their experiments showed that areas with more meltwater led to the growth of 50 percent more algae and places with more algae melted further.

This Antarctic summer has certainly seen a lot more meltwater than usual. Temperature records keep rising, leading to rapid melting at a scale previously only seen in the Northern Hemisphere.

Reading

Check

1. What really caused blood-red snow in Antarctica?

A. Too many penguins were killed.

B. The sunlight made it by mistake.

C. Some algae contributed to it.

D. The scientists did more experiments.

2. According to the researchers, what's the disadvantage of the algal blooms?

A. More ice and snow will melt.

B. More animals find few shelters.

C. Temperatures keep dropping.

D. It's unfit for scientists to research there.