2 . Johan Ernst Nilson is an explorer. His 32 expeditions in 100 countries include biking from northern Europe to Africa, hiking across Alaska and climbing the highest mountain on each of the seven continents. This summer, Nilson completed his most challenging journey the Pole to Pole Expedition. He travelled about 21,750 miles through 17 countries, from the North Pole to the South Pole. “I go to remote areas where no person has ever set foot,” Nilson told TFK.

Nilson walked, sailed, skied, biked, and took a dogsled. Known as the “environmental explorer”, Nilson used forms of transportation that are not harmful to the environment. Nilson hopes the expedition, which will be featured in a movie and a book, both due out this winter, will inspire others to protect the planet.

It took Nilson about 18 months to complete the expedition. He faced dangerous situations, just as the early polar explorers did. He travelled through hurricanes. He endured extreme heat and cold. He fell through ice. He suffered cracked ribs and frostbite(冻伤). He was even chased by bears.

Eating properly was a constant challenge. The explorer, who covered about 60 miles a day, ate a variety of foods, such as fruit, meat, fish and vegetables. At one point, Nilson ran out of food. He wrote on his blog: “The North Pole is a different story. On an expedition on the ice, you have to eat anything you can find.”

In spite of the many challenges, Nilson insists that the expedition was well worth it. He was able to visit with groups such as UNICEF and the American Red Cross, to take part in the work that they do to help people all over the world. He is hopeful that his adventure will inspire others to take action to protect the planet.

Nilson says his big expedition days are now over, but he will continue to explore in other ways. “Exploration is reaching for the unknown, learning how to play the piano, learning a new language,” he says. Are you an explorer, too?

3 . Chemists have spent the past century trying to make plastics break down in seawater. Most plastics take centuries to fully break down in the ocean.     1     However, this may change. Scientists have designed a new kind of plastic that can break down in seawater within weeks, not decades or more.

    2     It is known as polylactide (聚乳酸) or PLA. It’s made by linking many building blocks into a long string. Scientists had hoped PLA would quickly break down in the environment. And in some places it does, but not in seawater. After three years in the ocean, LA remains largely unchanged.

Timo Rhein Berger is a PhD student at the University of Twente in the Netherlands.     3       For part of that work, he became part of a team that just added some biology-inspired breaking points to PLA. They put those breaking points to places where monomers (单体) in the PLA molecules are linked. Then, they soaked (浸泡) their samples in artificial seawater. In this way, they measured how fast the PLA broke down. As the team had hoped, seawater attacked the weakened links between monomers. That could tear the PLA chain apart.     4    

When the researchers weakened 15% of PLA’s monomer links, the PLA broke down entirely within just two weeks. When they weakened only 3% of the links, the breakdown took about two years.     5     This can be achieved by adjusting how many weakened links it has.

As one of the most well-known tourist destinations in China’s Guangxi Zhuang Autonomous Region, Li River     1    (attract) millions of visitors each year.     2    , the river’s water quality has suffered greatly     3     increasing tourists, many of     4     threw garbage into the river. Previously, many tour boats,     5     number of commercial and industrial     6     (enterprise) as well as the rising local population led to severe water quality issues,     7    (cause) a decrease in the number of fish species. Luckily, many measures have been taken     8    (restore) the river’s original beauty. It’s believed that the beauty of the Li River     9    (preserve) for generations to come. With the policy of “Water Ten Plan” and the “River Chief System”, China’s waterways are heading towards a clean and     10    (sustain) future.

As we know, Earth is getting warmer and warmer,     1     results in melting ice and rising sea levels. In 2013, a dead polar bear     2    (find) on Norway’s Arctic island of Svalbard. Experts said that it was low sea-ice levels     3    (cause) by climate change     4     killed the polar bear. Scientists often mention that the “man-made” greenhouse effect is a big problem.    5     rise in temperature has led to an increase in extreme weather and natural disasters worldwide,     6    (cause) serious damage and costing human lives. The further global warming resulting     7     the continued greenhouse gas emissions     8    (require) the attention of people all over the world. Governments need to make policies and take measures     9    (reduce) greenhouse gas emissions. As individuals, we should also reduce our “carbon footprint” by restricting the amount of carbon dioxide our     10    (lifestyle) produce.

7 . Human activities have caused severe narrowness in over half of the world’s largest lakes in the past 30 years, causing risks to health, economies, and the environment, according to a study in the journal Science. The global decline in water storage equals to 17 times the capacity of Lake Mead, the largest lake in the U.S. Overuse of water for agriculture, development, and human-caused climate change are the main factors driving the decline, particularly in natural lakes. The accumulation of dirt and sand behind dams also contributes to the fall of water levels in lakes.

The findings showed “significant declines,” stated Fangfang Yao, the lead author of the study. “Roughly one-quarter of the world’s population lives in a basin with a drying lake,” Yao said. “So the potential impact could be significant.”

At least half of the decline in natural lakes was driven by human-caused climate change and overconsumption, which should remind water managers to improve protection and water efficiency, according to Yao. “If you know a lake is falling and that loss resulted from human activities, can we attach more importance to protection and improving water efficiency?” she said.

A climate change-driven drought and an ever-growing human thirst have continued to consume the two largest lakes in the U.S. Lake Powell and Lake Mead, which the Colorado River feeds. Lake Chad, one of Africa’s largest freshwater lakes which supplies nearly 40 million people with water, has shrunk (收缩) by an estimated 90% since the 1960s.

The United Nations regards access to safe drinking water as a universal human right, yet around 2 billion people lack access to it, and half of the global population experiences severe water shortage annually.

“Uncertainties are increasing,” said Richard Connor, the editor-in-chief of a U.N. water report published earlier this year at a press conference in late March, where world leaders met to try and find better strategies for managing the planet’s rare freshwater. “If we don’t address it, there will definitely be a global disaster.”

China is emerging as a global leader in aviation (航空) decarbonization (脱碳), according to industry experts. This development is     1     result of the scale of the country’s aviation market and     2     (it) new technologies and policies aimed at reducing carbon emissions (排放), they said.

“As the world’s second-largest economy, China     3     (expect) to be the world’s largest aviation market by 2030. We believe China plays an important part in aviation decarbonization with a deep impact on the decarbonization of aviation     4     (global),” said Martin Thomsen, senior vice-president of Air BP, the specialized aviation division of BP, previously     5     (know) as British Petroleum, a London-based multinational.

“We believe that this will lead to an expansion of SAF production,     6     could supply domestic and global markets     7     play a key role in supporting the decarbonization of supply chains,” he said.

Despite current challenges in raw material supplies, technology and policies, China’s SAF industry faces significant opportunities and     8     (have) certain advantages, said Luo Zuoxian, head of intelligence and research at the Sinopec Economics and Development Research Institute.

It will make important     9     (contribution) in reducing carbon emissions in the aviation industry, helping achieve the carbon neutrality (碳中和) goals and     10     (ensure) energy safety in SAF, he said.