Part of Antarctica is already green due to blooms of algae（水藻花）living on the snow. 【小题1】 However, it isn't clear what this will mean for the climate.

Patches（块）of “snow algae” have been known about for decades in the Arctic.【小题2】 Satellite images were used to identify patches of green on the snow-covered surface of Antarctica, which is warming the fastest.

It was found that in total, there were 1679 blooms of snow algae that covered up to 1.9 square kilometres at the height of summer when the blooms are largest.【小题3】 The temperature has to be warm enough for the snow to melt and there has to be a source of nutrients-mostly penguin guano（鸟粪）.

【小题4】 And it also destroys some of the algae’s home. But it would also mean more areas of melting snow further inland, so there could be a net increase. It isn't clear what more algae would mean for the climate. It is estimated that the algal blooms absorb 479 tonnes of carbon dioxide from the air every year. The amount of carbon that's in there is relatively small. However, this may increase if the blooms become more widespread.

While the algae may remove some carbon dioxide from the air, they also darken the white snow causing more of the sun's heat to be absorbed. In the long run, climate change could cause or problems for the algae because temperatures could rise so much that the continent's snow completely melts. 【小题5】 If it warms up a lot, the whole system could crash completely because there's no snow.

A lot of manufactured glass today made from sand and sodium carbonate (碳酸钠) can be reused or melted down and recycled into new items, but it doesn’t break down in the environment and will sit in landfills for thousands of years. A team of Chinese scientists aimed to deal with this environmental concern by developing an eco-conscious alternative.

In a study published recently in the journal Science Advances, a team at the Chinese Academy of Sciences’ Institute of Process Engineering describe how they engineered biodegradable glass made from amino acids (氨基酸). That glass would have a smaller impact on the environment and can break down in a few weeks or in several months.

In a test, glass beads made out of amino acids were placed under the skin of mice, and the breakdown of the bead and the skin healing process were observed for 30 days. A diagram from the study shows how the mice’s bodies broke down the beads. In that month, the glass implant degraded beneath the skin, the wound site healed, and fur grew back. “Throughout the experimental period, no mice exhibited any pain-related behavior that may have been caused by the glass implantation, and none of them experienced obvious weight loss,” the researchers wrote in their paper.

Although amino acids do degrade over time in the environment, this biodegradable glass is not as durable as traditional glass, because amino acids can break down quickly in heat. To overcome this problem, the researchers chemically modified amino acids using the heating-cooling process tailored for manufacturing the new glass. This is when materials for the glass are heated to become soft and then rapidly cooled so as to make the glass tougher.

“It’s important to point out that this biodegradable glass is currently in the lab stage, and far from large-scale commercialization,” emphasized Yan Xuehai, a professor involved in the study, in a press release.

King Canute couldn’t stop the ocean’s tide from rolling in — can Africa hold back the desert?That’s certainly what the continent is tying to do with its proposed “Great Green Wall”, 800km (almost 500 miles) worth of trees that officials hope will stop the advancement of the Sahara Desert, which has been rapidly expanding southward.

The idea was introduced in the 1970s when the once-rich region turned barren (贫瘠的) due to climate change and intensive land use. But it’s not a new idea; China has its own desert vegetation project to hold back the Gobi Desert! Thanks to the Chinese plan, the African project aims to plant 100 million hectares of trees by 2030 across the entire Africa. The initiative is a decade in, and around 15% completed, and there have already been benefits for many communities and wildlife. It’s bringing life back to the continent’s degraded landscapes at an unprecedented scale, providing not only food security and jobs but a reason to stay for the millions who live along its path.

The creators of the wall hope it will bring an urgently needed solution to the threats facing the African continent, creating 10 million jobs in rural areas, as well as preventing 250 million tons of carbon. The initiative is Africa-driven, which for those on the continent, is vital, and may hold the key to success. “The Great Green Wall…is about ownership, and that has been the failure of development aid because people were never identified with it,” said Elvis Paul Tangam, African Union Commissioner for the Sahara and Sahel Great Green Wall Initiative.“But this time they identify. This is the very thing of us!”

The wall may seem like a moonshot, but all the best ideas usually are. As Thomas Sankara, former president of Burkina Faso said in 1985, “You can not carry out fundamental change without a certain degree of madness. The courage to turn your back on the old formulas, the courage to invent the future.”