题型:阅读理解 题类:模拟题 难易度:普通
上海市嘉定区2020届高考英语一模试卷
A tiny clue found in ancient deposits has unlocked big secrets about Greenland's past and future climate. Just beyond the northwest edge of the vast Greenland Ice Sheet, researchers have discovered lake mud that have survived the last ice age. The mud, and remains of common flies in it, record two interglacial periods(间冰期)in northwest Greenland.
Although researchers have long known these two periods—the early Holocene and Last Interglacial—experienced warming in the Arctic, the mix of fly species shows that Greenland was even warmer than previously thought. "As far as we know, it has never been found in Greenland. We think this is the first time anyone has reported it in ancient deposits or modern lakes there," Axford said. "We were really surprised to see how far north it migrated (迁徙)."
This new information could help researchers better measure Greenland's sensitivity to warming, by testing and improving models of climate and ice sheet behaviour. Those models could then improve predictions of how Greenland's ice sheet might respond to man-made global warming. After all, Greenland covers 80 per cent of the Arctic country and holds enough ice to equal 20 feet of global sea level. "Northwest Greenland might feel really remote, but what happens to that ice sheet is going to matter to everyone in every coastal city around the world," said Yarrow Axford, an associate professor in the team. "One of the big uncertainties in climate science is how fast the Earth changes when it gets warmer. Geology gives us an opportunity to see what happened when the Earth was warmer than today," said Axford.
People might be surprised to see how today's Greenland looked during the last two interglacial periods. During the Last Interglacial, global sea levels increased by 15 to 30 feet, largely due to thinning of Greenland and Antarctica's ice sheets. However, now researchers believe northern Greenland's ice sheet experienced stronger warming than previously thought, which could mean that Greenland is more responsible for that sea-level rise.
Finding lake deposits older than about 10,000 years, however, has been historically very difficult in Greenland. To measure these ancient temperatures, researchers look to ice cores (冰核) and lake deposits. Since ice and lake deposits form by a gradual buildup on annual layers of snow or mud, these cores contain history of the past. By looking through the layers, researchers can obtain climate clues from centuries ago.
A. A general sleep rule. B. The importance of sleep. C. A funny sleeping example. D. Different levels of sleep. E. The time we need for sleep. F. Different states of sleep. |
{#blank#}1{#/blank#}
Sleep, as we know, is important to us because it helps restore tired organs and tissues in our body. But how much sleep do we actually need?
{#blank#}2{#/blank#}
For most of us, eight hours seems to be about the right amount. Yet we know that there are a great many people who get along perfectly with less sleep and some who may even need more. A great deal depends on the way we live. But a good general rule to follow is to sleep as long as we have to in order to feel happy and be able to work at our best when we are awake.
{#blank#}3{#/blank#}
There are actually different levels of sleep. There is a deep sleep and a shallow sleep. In a shallow sleep our body does not get the same kind of rest as it gets in a deep sleep, so that after eight hours of a shallow sleep we may still feel tired. But a short deep sleep can be very restful.
{#blank#}4{#/blank#}
Alexander the Great was able to get a deep sleep whenever he needed it. Once, during the night before an important battle, he remained awake longer than anyone else. Then he wrapped himself in a cloak and lay down on the earth. He slept so deeply that his generals had to wake him three times to give command to attack!
{#blank#}5{#/blank#}
Normally when we go to sleep, our “ sleep center” blocks off nerves so that both our brain and our body go to sleep. One prevents us form wanting to do anything and the other makes our internal organs and limbs go to sleep. But someone will fall asleep (brain sleep) and keep on marching, because his body is not asleep!
Amsterdam Destination Guide
Amsterdam is one of the most popular travel destinations in the world, famous for its beautiful canals, top art museums, cycling culture and so on. It is the capital and most populous city in the Netherlands and often referred to as the "Venice of the North" because of its expansive system of bridges and canals. Here are some of the key points to remember as you plan your trip to Amsterdam.
Boom Season | Population | Language(s) | Currency | January Climate | July Climate |
May to October | 813,562 | Dutch | Euro | Average high: 5.8 ℃ | Average high: 22.0 ℃ |
Must-See Attractions
Most visitors begin their Amsterdam adventure in the Old Centre, which is full of traditional architecture, shopping centers, and coffee shops. You'll also want to check out Amsterdam's Museum Quarter in the South District, which is great for shopping at the Albert Cuyp Market and having a picnic in the Vondelpark. The top museums to visit there are the Rijksmusuem, the Ann Frank House, and the Van Gogh Museum.
If You Have Time
There are several other unique districts in Amsterdam, and you should try to explore as many of them as time allows. The Canal Ring is a UNESCO World Heritage Site that was originally built to attract wealthy home owners and is a center for celebrity spotting and nightlife today. The Plantage area has most of the city's museums, including the Jewish Historical Museum, the Scheepvaart Museum, and the botanical gardens.
Money Saving Tips
Unless you really want to see the tulips (郁金香) blooming, avoid booking between mid-March and mid-May. This is when hotel and flight prices rise.
Look for accommodations in Amsterdam's South District, where rates are generally cheaper than in the city center.
Buy train tickets at the machine instead of the counter to save a bit of money.
Instead of hiring a tour guide, hop on a canal boat. They're inexpensive and will give you a unique point of view of the city.
Check out our homepage to view price comparisons for flights, hotels, and rental cars before you book.
试题篮