5 . On Sept. 21, 2020, scientists announced that Arctic sea ice has already lost two-thirds of its amount over the past four decades. It is part of a shocking trend in polar heating that is already seeing impacts across the globe.

Throughout the spring and summer, Arctic sea ice melted away faster than it usually does, causing the largest loss of Arctic sea ice cover since satellite records began in the 1970s. This year's minimum was reached on September 15, at 3.74 million m² compared with the previous low—4.17 million m²—set in 2007.

What's causing this loss of sea ice? The short answer is our heating climate. A recent study showed that the influence of heat has more than doubled over the past decade or so, which means the melting of nearly a meter thickness of sea ice each year.

The biggest effects of the loss of Arctic sea ice, of course, will be felt locally: from the more possible snowfall to more storms with stronger winds. These will also cause waves as well as rising temperatures. In fact, the increased temperatures transformed northern forests into tinderboxes ready to burn. That melt also means polar bears are losing critical habitat and Inuit hunters are losing ice to preserve their traditions and culture.

On a larger scale, the greatest impact may be the changes in the Arctic 's ability io function as a cooling system for the global ocean. A warmer Arctic will affect the temperature differences between the northern polar region and areas further south. That may, in turn, create stronger heat waves, droughts, floods and potential impacts on farming. And all of us will be more exposed to the disastrous effects of climate breakdown.

We need to hit the reset button right now on how we look after each other and Arctic sea ice to help our planet cope with the climate breakdown.

6 . Mountain

A mountain is a landform that rises high above its surroundings. Taller than a hill, it usually has steep slopes and a rounded or sharp peak. Mountains are rarely found alone.     1     Lines of ranges form mountain belts.

Some mountains were formed by the activity of volcanoes. Scientists believe that most volcanic mountains are made up of rock that melted deep within earth. The rock rose through Earth’s surface, or crust. It then flowed onto the surface in the form of lava.     2     Volcanic mountains are typically steep. Mount Fuji in Japan, Mount Kilimanjaro in Africa, and Mount Rainier in the United States are examples of volcanic mountains.

Other mountains were formed by movements within Earth’s crust. The theory called plate tectonics explains this type of mountain building. Earth’s crust is divided into huge pieces called plates, which move very slowly. The continents sit on top of the plates and move with them. At times the plates strike against each other, forcing the rock upward. The Himalayas of Asia are an example of this type of mountain chain.     3    

Mountain ranges are natural barriers to travel. Roads are difficult to build across them. Railroads need expensive tunnels to cross even low mountains.     4     They often form borders between countries.

Life is hard in mountain lands. The high places of the world are cold and have little soil, making farming difficult.     5     Skiing and climbing are popular mountain sports.

7 . Welcome to South Pole

Is it cold?

Yes! Be very careful out in the open air! The temperature is between -21℃ in the summer and -78℃ in the winter, and you can become numb with cold without realizing. There’s heavy frost even on the warmest summer days, and if it’s quiet you can hear your breath freeze. So if you leave the station, dress warmly and carry dry clothing and a portable radio.

Is there anything good about the weather?

The air is very pure, and it doesn’t snow very much — only about four millimetres a year. There’s very little wind and the sky is usually clear. It’s possibly the calmest place on Earth.

Is it safe?

Because the South Pole is a high altitude site, the glare of the sunlight here is very terrible. It’s also reflected by the snow, so if you go outside, remember to wear sunglasses and use suncream. If you don’t, there’s a severe risk that you’ll damage your eyesight or get badly sunburnt.

What’s it like to live here?

Life is quite abnormal. Sunrise and sunset come once every six months, and in the winter the total absence of daylight can be tiresome, and for some, depressing. We’re totally isolated except for radio and electronic communications, as no aircraft can fly here for about eight months. Usual equipment doesn’t always work as it should do. If you use an electric drill, the power cord will snap. Photography is tricky too, as film is fragile and the camera battery doesn’t work in the cold.

8 . Earth’s longest artificial structure is usually said to be the Great Wall of China. Just how long that is is hard to say, for northern China actually has many walls, built at different times and not always interconnecting. Earth’s second-longest artificial structure, though, is not a wall, but a fence. Its length is known exactly. It stretches for 5,614km across eastern Australia and is intended to stop the country’s native feral dogs, the dingoes, which live mainly to its north, from preying on sheep, which are farmed mainly to its south.

Australia’s dingo fence is remarkable. But it does not stand alone. Millions of kilometres of fences wrap the world. Some are intended to control the movement of animals, some the movement of people, and some merely to mark the limits of territory, so that everyone knows who owns what. Even fences built for other purposes, though, often serve to limit animals, too. Such worries are not foolish. Hardening borders in Central Asia, coupled with the expansion of fenced railways, have reduced numbers of another large, endangered mammal, the saiga antelope.

No sitting on the fence, please Smarter fencing can help. In the American West, for example, Montana and Wyoming are mounting campaigns to replace decades-old fences with ones that are more ecologically friendly. The changes required are often small. Making fences low enough for deer to jump over helps.

Adding poles improves a fence’s visibility, stopping unfortunate collisions at speed. And not all wire need be barbed(带倒刺).

There is, though, also a need to paint a clearer picture of where fences are, and to remove those past their prime. Such structures are seldom well-documented and are difficult to pick out in satellite photographs, so doing this can be hard. Jeffrey Masek, a specialist in Earth-imaging at NASA, America’s space agency, suggests instead using commercial drones, which fly at low enough altitudes to capture detailed pictures. Deserted fences are of use to neither man nor beast. To beasts, in fact, they are positively disgusting.

9 . New Zealand is one of the best countries in the world to experience how life might have been in prehistoric times. New Zealand is a nature lover’s paradise(乐园) with its conservation reserves.

The Kaharoa Conservation is home to a number of endangered birds and the North Island Kokako is just one of them. The Kokako is possibly New Zealand’s most beautiful songbird with such a variety of whistles, clicks, buzzes and whirrs in its sound range, one bird sounds like a chorus!

Rich in Maori history, the Mokaihaha Ecological Area has high conservation and scientific value. Birdlife features this natural wonderland with the symphony including such stars as the Tui, Kereru, Fantail, Bellbird and the endangered Kokako.

If mountain biking is your thing, then this is the place for you! The Whakarewarewa Forest provides a network of tracks through exceptionally impressive scenery that has made Rotorua famous for its mountain biking.

A project of great ecological importance is being undertaken by a community aimed at the restoration of Maungatautari volcano forest.

The volcano forest has sustained the lives of its wildlife for hundreds of years but since the introduction of European pests such as deer, rabbits, goats, pigs and rats, the native varieties of mammals, birds and plants have been facing threats.

The aim of the courageous project is to get rid of all introduced pests from the 3363 hectares of forest. Luckily, life in the forest of Maungatautari is beginning to awaken again.

10 . First established as a state capital in 229 CE, Nanjing, China, has long been one of the country’s most important (and largest) inland river ports and is recognized as one of the Four Great Ancient Capitals of China.

Why do people love it?

    1    Xuanwu Lake provides a peaceful escape right in central Nanjing, with temples, teahouses and restaurants located in nearby Xuanwu Lake Park. Unlike city walls in Beijing or Xi’an, Nanjing’s old wall isn’t geometric and instead contours the lake and mountain areas.     2    The sense of surprise delivered by these central natural expanses, like the Yangtze River, Zhongshan Mountain range and Xuanwu Lake, is what new residents love about living here.

What’s it like living here?

For those who miss the foods of home, there’s no shortage of foreign restaurants and cafes that cater   to   expats   and   international   students.       3    Nanjing has an efficient and expansive metro system that covers most of the city, but cycling is also an option, with bike-friendly wide and straight roads.

Residents rave about how affordable Nanjing is compared to other Chinese cities, especially when it comes to housing.     4    That said, the weather can be rough in winter, since most buildings lack central heating. Summers are also very hot and humid.

In general, a certain traditionalism and conservatism can be felt more strongly here than in other Chinese cities, which can make it more of a challenge to make local friends quickly. The language and cultural barrier tends to be high.     5