High-Q | חטיף 5

12

חטיף מס '5

אנגלית

Text II (Questions 18-22)

One can find weather oddities at any time in history, but the recent trends meteorologists are tracking are different. “These could be the beginning of global warming,” says researcher Kevin Trenberth. “There has been a clearly documented increase in humidity in the lower atmosphere. The increased heating moistens the atmosphere, and that moisture is fuel for storms.” 5 A team of climate scientists led by Michael Mann has produced a report on the increased warmth around the globe since the time of the Middle Ages. He analyzed hundreds of records collected by colleagues that show tree rings, ice cores, lake sediment layers, and other indications of temperature going back over 700 years. The analysis supports, in unprecedented detail, existing conclusions by the United Nations that the recent 10 warmth observed on the planet is not only extreme but is rising ever faster. The reason seems clear. “This unusual warming starts in the 19 th century and accelerates right through the 20 th century,” Mann says. “It is not related to earlier variations of temperature over the centuries, but closely tracks emissions of greenhouse gases.” Mann’s report also says that its reconstruction of past climate closely parallels other researchers’ computer simulations 15 of those centuries. This adds credibility to those models’ predictions of a further, even faster rise in temperature in the next century. Some historians argue that a previous period of warmth during the Middle Ages brought prosperity to Europe, and that warmer weather is better weather. Others are not so optimistic. But whether the prospects are good or bad, “if what we are seeing is just the tip 20 of the iceberg compared to what happens in the 21 st century, then there will certainly be huge environmental and economic impacts,” Mann says of the rising heat.

Questions

18. The primary topic of the passage above is -

(1) computer simulations of the earth’s climate (2) a recent study of earth’s climate history (3) predictions about the results of global warming (4) the effects of increased humidity on the weather

19. The term “These” in line 2 refers to -

(1) oddities (2) meteorologists (3) rains (4) storms

© כל הזכויות שמורות לחברת High Q Global