Before then, even large hurricanes could have gone unnoted among the scattered ships and settlements of the Caribbean and Gulf of Mexico. But there are old archives still unsearched and records left to correlate, so studies of historical documents can yet yield valuable data. And in China, good records of Pacific typhoons go back more than 1000 years.
Clearly a complete hurricane record is not possible, but then the majority of hurricanes are not significant for our purposes. For practical purposes—say, for insurance companies and government agencies—we want to know about the very largest storms. Those few hurricanes are better known, and their dates and trajectories can be checked against the geologic record where suitable data exists.
The Geology of Hurricanes
Hurricanes bring water with them that has a particular isotopic composition, but these storms are so temporary that they may leave no trace in the usual geologic records. There is cutting-edge research that may be able to detect signs of hurricane passage in corals, but for the most part biology-based studies, in tree rings and corals, can only tell us about seasonal climatic conditions on land and in the sea. That is better than nothing, but only sedimentary evidence can give us what we need.
Hurricanes are known for pushing huge piles of water, called storm surges, onto the land as they rges carry beach sand with them and leave it blanketed on the shore and beyond. The best sites for preserving these overwash sand beds are coastal lakes, and a handful of researchers at Louisiana State University, University of Florida, University of South Carolina and elsewhere are digging through the mud up and down the coast.
Other natural events can create similar sand beds, most notably river floods, tsunamis and shifting rivers. Careful study can often determine which interpretation is correct: rivers bring terrestrial sediment, which can easily be distinguished from marine sediment; tsunamis affect much larger regions than hurricanes; and rivers shifting course (avulsion) do not build up the elevation of the land.
The sea level has been rising slowly for the last 10,000 years. This has caused the coasts to build upward in response, steadily burying a sediment record of hurricanes and other climatic information. In addition, the coasts have been sinking from the weight of the sediment deposited on them. New sediment keeps the coasts at sea bsidence of the U. S. Gulf coast, one reason the region was so vulnerable to Hurricane Katrina, is what preserves traces of paleo hurricanes
Progress test
variant 1
GRAMMAR
1 Complete the sentences. Use the correct form of the verb in brackets.
Example: I’ve never read (read) a book in English.
1 My brother _______ (study) really hard at the moment.
2 Let’s eat Thai food. I _______ never _______ (try) it.
3 We _______ (fly) to Bermuda at 10 o’clock next Saturday.
4 When they got to the hotel they _______ (have) a meal.
5 When _______ Pedro _______ (go) back to Spain? Is it tomorrow?
6 _______ you _______ (wait) for Paul when I saw you this morning?
7 I _______ (see) your mum in town on Friday when I was shopping.
8 I _______ (not be) late tonight. That’s a promise.
9 Be careful. I _______ just _______ (paint) the door.
10 _______ you _______ (be) to London before?
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2 Underline the correct form.
Example: When did you finish / have you finished your work?
1 Who did you see / saw at the party?
2 He is always / always is late for meetings.
3 I was giving / gave him a watch for his last birthday.
4 I’m going to / I’ll see you outside the restaurant at six o’clock.
5 She finished her homework early, so / but she watched TV.
6 His mother is a person who / which is never too busy to talk to you.
7 I don’t think it’ll rain / it is raining tomorrow.
8 Who did give / gave you those chocolates?
9 What did you do / were you doing last weekend?
10 Does your brother stay / Is your brother staying with you at the moment?
11 When did they get back / have they got back from holiday?
12 I was sitting / sat in the park when it started to rain.
13 Mr Jones will meet / is meeting someone at ten but he can see you at 11.
14 She usually gets on well / gets on well usually with her brother.
15 That’s the most difficult / more difficult question in the test.
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3 Complete the sentences with one word.
Example: Sorry, what did you say? I didn’t hear.
1 My car was less expensive _______ yours.
2 I’m sure he _______ be here soon.
3 She passed the exam _______ she studied hard.
4 A pilot is someone _______ flies a plane.
5 It was _______ best holiday I’ve ever had.
6 I’ve _______ seen the film. I saw it last week with Sue.
7 _______ he’s only ten, he speaks English very well.
8 I haven’t been to the new shopping centre _______. What’s it like?
9 The food wasn’t as delicious _______ it was last time.
10 My team _______ the competition. They scored more goals than the other teams.
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4 Put the words in the correct order.
Example: excellent I latest think his will film be
I think his latest film will be excellent.
1 your how students are many in there class?
__________________________________
2 this you go you’ll do camping think weekend?
__________________________________
3 next going are to where study year you?
__________________________________
4 as my well older me brother doesn’t as cook
__________________________________
5 car hired we the I’ve seen smallest ever
__________________________________
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Grammar total | 40 |
VOCABULARY
5 Underline the odd word out.
Example: trainers shorts boots shoes
1 cap T-shirt sweater top
2 generous mean funny friendly
3 polluted noisy crowded shy
4 hand heart brain stomach
5 thirsty windy foggy cloudy
6 buy hire spend sunbathe
7 blouse skirt dress scarf
8 arm back knee foot
9 campsite mountains hotel apartment
10 teeth hair mouth foot
10 |
6 Write the opposite.
Example: noisy quiet
1 dangerous _______
2 hard-working _______
3 tidy _______
4 interesting _______
5 polite _______
5 |
7 Complete the sentences with one word.
Example: Slim is the opposite of fat.
1 Students, please work in _______. Tell your partner about a famous photo.
2 When we’re on holiday we _______ an apartment because we don’t like hotels.
3 They got married _______ Valentine’s Day.
4 Why do you always use my dictionary? Give it _______; I need it.
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