2 . World Water Day

Everyone needs water, and every drop is precious. On 22 March, World Water Day draws attention to the essential role of water in our lives.     1       

We all need water to stay alive, but about two billion people around the world live without clean water in their homes     2     Many of them live in rural communities or in places where there are wars and conflicts. Meanwhile, climate change is making the little water they have access to less and less.

    3     Thousands of children worldwide die every day from diarrhea caused by dirty water. In some countries, people walk many kilometers every day to get water, and sometimes the water isn’t clean. If children spend most of their day walking for water, they can’t go to school.

In 1992, the United Nations made a special day for water, and World Water Day has been celebrated on 22 March every year since 1993. On this day, many countries hold events to educate people about the problems of dirty water.     4    

Some charities organize fundraising events for World Water Day. People do things like sponsored walks, cycles and swims.     5     , where people walk four, eight or 12 kilometers each day in March to see how it feels when they have to walk a long way to get their drinking water. People give them money to do these things, and all this money helps provide clean water to as many people as possible around the world. So, this World Water Day, what will you do?

A new report suggests Canada’s Western Hudson Bay polar bear population     1    (drop) 27 percent during the past five years.

Every autumn, bears     2     (live) along the western edge of the Hudson Bay pass through the sub-Arctic town of Churchill, Manitoba. The yearly movement has helped make the area’s bears one of the most studied     3     (group) in the world. Bear watching adds about $5.3 million to the local economy each year.

But a report     4     (recent) issued by the government in Canada’s northern territory(地区) of Nunavut found that just 618 polar bears remained in     5     area. This represented a 50percent drop in the population from the 1980s.

Polar bears depend on frozen salt water called sea ice     6     (help) them hunt seals for food   But the Arctic is now warming about four times     7     (fast) than the rest of the world. Around Hudson Bay, seasonal sea ice is melting earlier in the spring and forming later in the fall. This is forcing bears to go longer periods     8     food.

John Whiteman,     9     is chief research scientist at the nonprofit conservation group. Polar Bears International, called the population drop “totally shocking”. He said, “Scientists fear that if continued sea ice loss cannot     10     (stop), it will one day lead to a total loss of the area’s polar bear population.”

4 . 2005 was a big year for me. After my family moved to New Orleans in June, Hurricane Katrin a hit the _____ in August. I sat in my family’s car on a highway full of other confused children as we all _____ the city before the storm. A few months later, we returned to New Orleans. But the city was still ____. There were still thousands of people left homeless because of the ____.

Then some ____ people like the coach of New Orleans Saints were taking action. He gave money to schools and charities, helping _____ the city and feeding those who had ____ everything. He helped bring back the ____ that New Orleans once had. The people made it ____ and came back to the stadium to watch the game.

I remember when Louisiana Superdome reopened, the energy of the city ____. I remember when the coach ____ the field, there were loud cheers.   I remember how ____ I was when the Saints appeared.

I was too young to understand what the _____ had brought to New Orleans. _____, I’m old enough now to understand that the coach did so much for New Orleans. I’ll always be ____ for that. Even though he had retired, he would always be my idol.

5 . Objects in the night sky are disappearing from view because of light pollution, according to a new study. Outdoor lighting from street lamps, office buildings and vehicle headlights leads to sky less bright, which is when the night sky gets brighter. The brighter it is at night, the harder it is to see stars and planets from Earth.

Christopher Kyba, an astronomer with the GFZ German Research Center for Geosciences, led his team studying over 50, 000 star observations between 2011 and 2022. “If the brightening of the night sky continues at the current rate,” Kyba said, “a child born in a place where 250 stars are visible will only be able to see 100 stars by the time he or she turned 18.”

The issue is global but particularly common in North America, where 80% of people cannot see the Milky Way galaxy (银河系). This huge group of billions of stars should look like a wide strip of light in the dark night sky. However, only very remote places, such as the Sahara Desert and the Amazon Rain Forest, have a truly dark night sky.

Light pollution makes it harder for astronomers to study stars and planets. It also causes problems for animals. Animals active at night like bats become confused and crash into objects. Turtles that hatch (孵化)at night need moonlight to find the sea, but artificial lights can confuse them and make them head inland instead. Birds in cities often wake up and start singing earlier than they should. Human lights also cause themselves to produce less of a chemical called melatonin(褪黑激素). This can lead to sleep problems, headaches, tiredness, and mood issues.

To help, scientists want to raise awareness of light pollution. They suggest that people use outdoor lighting that causes less light pollution, such as motion-sensitive lights that switch on only when they’re needed.

The 14th Meeting of the Conference of the Contracting Parties to the Ramsar Convention on Wetlands (RAMSAR COP14) took place in Wuhan, Hubei Province in November. It was the first time that China    1    (host) this international event.    2    (know) as the kidneys (肾脏)of the Earth, wetlands are among the world’s three major ecosystems together with forests and oceans. China’s wetlands arc vast. diverse and widely distributed (分布),    3    (range) from the cold temperate zone to the hot zone. In recent years. China has been strengthening the protection and restoration of wetlands.    4    is remarkable is that more than 600 wetland nature reserves and 1.600 wetland parks have been established. China’s first law on    5    (specific) protecting wetlands took effect on June 1 this year.

Wuhan, the host city of RAMSAR COP 14. has 162,400 hectares (公顷) of wetlands, accounting    6    18. 9 per cent of its total area. In June,Wuhan    7    (award) Wetland City Accreditation by the Ramsar Convention,    8    international honor for the protection of urban wetland ecology.

Nature provides the basic conditions for human    9    (survive) and development. With a comprehensive approach to the conservation of ecosystems in place. China aims to boost their biodiversity, stability and sustainability. Wetland conservation is a crucial part of the country’s efforts to achieve    10    (it) green development goals.

7 . Not too long ago, 41-year-old Garrett Fisher flew in a small airplane close to the surface of Europe’s largest glacier(冰川), which is in Norway. In that environment, the plane carrying a man who photographed glaciers seemed almost like a toy.

Fisher often combines two activities he loves, flying and photography, trying to photo- graph every glacier on Earth. He wants his photos to show the beauty of glaciers before some of them disappear. Scientists say many glaciers are melting or getting smaller because the Earth's average temperature is increasing. By 2100, the size of European glaciers can decrease by between 22 percent and 84 percent. Nearly all small glaciers in Norway will likely disappear. For Fisher, this means that time is running out. The melting pushes him to try to photograph them before it is too late.

As a child, Fisher lived next door to a small airport in the state of New York. His grand- father was a pilot and took Fisher on plane rides when he was a young child. His grandfather would tell him, “Whatever you set your mind to, you can do. ”

In the late 1990s, a friend told Fisher that the world’s glaciers were disappearing. This pushed him to combine his love of flying and photography to photograph the Earth's remaining glaciers. He believed he was in a race against time and that his photographs could be of great value to future generations. So, he launched Global Glacier Initiative, a non-profit group to support and show his work, and he planned to open his photos to the public for research.

Some people will ask him why he always risks flying over glaciers when satellites have already given pictures of them. Fisher says, “Satellite images can't really show the loveliness of glaciers the way my photos can. My photos show the colors and shapes as the light from the sun hits them. Science has all of the data we need. The problem is that it’s not beautiful. ”

9 . In a paper published in Nature Communications, a team led by scientists from the University of California, using climate models and satellite data, reveal for the first time how protecting tropical forests can yield climate benefits that enhance carbon storage in nearby areas.

Many climate scientists use computer simulations (模拟) to mimic the planet's climate as it exists today and how it may exist in the future as humanity keeps emitting greenhouse gases. Such models rely on accurate measurements of all the moving parts of the climate system, from how much sunlight hits and warms the climate, to the response of forest biomass (生物量) to changes in temperature, rainfall and atmospheric carbon dioxide levels.

Jim Randerson, UCI professor of Earth system science, said, “This paper shows that avoiding deforestation yields carbon benefits in nearby regions as a consequence of climate feedbacks.”

He explained that for a new patch of deforestation in the Amazon, the regional climate changes that happen as a result led to an additional 5.1 percent more loss of total biomass in the entire Amazon basin. In the Congo, the additional biomass loss from the climate effects of deforestation is about 3.8 percent. Tropical forests store about 200 petagrams of carbon in their aboveground biomass. Since 2010, deforestation has been removing about 1 petagram of that carbon every year. (One petagram is equal to 1 trillion kilograms.)

Until now, climate modelers have, for lack of data, not considered tree mortality (死亡率) in their climate simulations. But by combining satellite data with climate variables, they obtained information about how sensitive carbon stored in vegetation is to climatic changes that result from tree mortality and fire.

10 . Humankind’s growing need for food is in conflict with thousands of other species’ need for space. By 2050, humans may need to clear an additional 3.35 million square kilometers of land for agriculture. Changing the largely natural habitat would remove more than 17,000 species from the land, researchers report in Nature Sustainability.

“But changing how, where and what food is grown can reduce the effect,” says scientist David Williams of the University of Leeds. “We can feed the planet without making it too bad.”

To figure out how, Williams and his colleagues first identified habitat most likely to be cleared for cropland. The team then calculated how much food 152 countries would need to feed their growing population and mapped where crops would likely be grown in each, based on past land use changes. By 2050, the world’s 13 million square kilometers of cropland would need to increase by 26 percent, the team found. That growth is largely concentrated in Sub-Saharan Africa, South and Southeast Asia.

The researchers then put these estimates (估计) on distribution (分布) maps of nearly 20,000 species. While almost all of these species would lose some habitat, the team estimated 1,280 species would lose at least 25 percent of their range and that 96 species would lose at least 75 percent.

“Changing the global food system could cut these losses,” the team says. Among the changes are improving crop output and increasing food imports for food-poor countries. Adopting these measures would actually reduce the world’s cropland area by 3.4 million square kilometers by 2050 and result in just 33 species losing more than a quarter of their natural range, the team found. “Achieving that may be difficult and needs governments’ effort,” Williams says, “but emptying our plates at the family dinner tables could still have big effects.” “The world needs to feed a growing population, but it can be done more sustainably (可持续地),” he says.