B5 U6 Hotter in the City

Unit 6  Hotter in the City

Reading

No other places on Earth seem to be as hot as cities in summer. There’s a good reason why city dwellers ([`dwEl2] n. [C]居住者，居民dwell [`dwEl] vi. (fml.) 居住dwelling [`dwElI9] n. [C] 住處，住所) flee to the countryside to cool off (使涼快，涼快下來；冷靜下來) during the heat of summer. Owing to what is called the “urban heat island” (UHI) ([`3b1n hit `aIl1nd] n. (abbr. UHI)熱島urban [`3b1n] adj.城市的，都會的) effect, cities with populations of a million or more can be 1-3 degrees centigrade ([`sEnt1&Gred] adj.攝氏溫度的) warmer—and as much as 12°C warmer in the evening—than the surrounding areas.

Why are cities hotter? People, buildings, and the machinery ([m1`Sin1rI] n. [U](大型) 機器，機械) in cities generate ([`dZEn1&ret] vt.產生，製造generator [`dZEn1&ret2] n.[C]發電機) heat. Air conditioning ([&Er k1n`dIS1nI9] n. [U] (abbr. AC)空調系統), for example, can raise temperatures by more than 1°C. Concrete jungles ([&kAnkrit `dZ^9GL] n. [C] (usu. sing.)混凝土、高樓林立的擁擠市區concrete [`kAnkrit] n. [U]混凝土jungle [`dZ^9GL] n. [C] (熱帶)叢林，森林) store more heat during the day than plants do; then at night, they send out (發出 (熱、信號等)) some of that heat, contributing to the higher temperatures there. There is also often less reflectiveness ([rI`flEktIvn1s] n. [U]反射reflective [rI`flEktIv] adj.反射的，反光的) in cities, which causes them to absorb more of the sun’s heat.

However, according to a recent study, it turns out that the local climate may be the main factor behind the UHI effect. Researchers detected ([dI`tEkt] vt.察覺) some trends ([trEnd] n. [C]趨勢，傾向) in NASA ([`n8s1] n. abbr. (= National Aeronautics and Space Administration)美國太空總署) satellite ([`s8tL&aIt] n. [C]人造衛星衛星) data and created a computer model to evaluate ([I`v8lj5&et] vt.衡量，評估evaluation [I&v8lj5`eS1n] n. [C]衡量，評估) the importance of the various factors that might have an influence on the UHI effect. These factors include evaporation ([I&v8p1`reS1n] n. [U]蒸發，揮發evaporate [I`v8p1&ret] vi.蒸發，揮發), heat created by humans and their structures, and heat stored by cities. Differences in land surface types and in convection ([k1n`vEkS1n] n. [U](氣體、液體的) 對流) are also included.

Based on this model, the researchers determined that these last two factors were the decisive ([dI`saIsIv] adj.決定性的，關鍵的) ones, and that they interacted ([&Int2`8kt] vi.互相影響，交互作用interaction [&Int2`8kS1n] n. [U] 互相影響) with the local climate. In humid ([`hj5mId] adj.潮溼的humidity [hj5`mId1tI] n. [U] 溼氣，溼度) areas, cities are usually three degrees warmer than the neighboring countryside, for convection is less efficient at dispersing ([dI`sp3s] vt.散布，分散) heat from urban land than from rural land. On the other hand, the dense vegetation ([&vEdZ1`teS1n] n. [U]植物，植被) of a rural area steps up (使某事加速，使某物增加) the efficiency of the convection process, letting more heat move from the land into the atmosphere.

In dry regions, where rural vegetation is lacking, the opposite ([`Ap1zIt] n. [C]完全不同、相反的人或事物opposite [`Ap1zIt] adj. 截然不同的，完全相反的) occurs. On average, urban land is about 20 percent more efficient at removing surface heat by convection than rural land. And in a few of the cities in dry regions, the convection difference is so notable ([`not1bL] adj.顯著的，值得注意的) that these cities experience no UHI effect.

At night, though, no matter what the local climate is, the release of heat stored up during the day creates a heat island effect. Heat gets trapped ([tr8p] vt. (trapped | trapped | trapping)保存(氣體、液體、熱量等)n. [C]陷阱，圈套) in the shallow ([`S8lo] adj.淺的，不深的) layer ([`le2] n. [C]層，表) of the atmosphere near the surface. In order to disperse, it is forced to move more horizontally. In bigger cities, the heat has to move farther to escape; as a result, the center of a city tends to be much warmer than the middle of a town.

The UHI effect is more than just an annoyance ([1`nOI1ns] n. [C]令人惱怒的事n. [U]惱怒，生氣) for city­dwellers—it can also worsen the problems associated with heat stress ([`hit &strEs] n. [U]熱病). Fortunately, the research has put forward (提出某事，提議某事；將某事提前) some ideas about which measures might help to lower some of that heat. Reducing the heat from air conditioners and other machinery to cool the city might seem like an effective solution, but the computer model suggests that such measures won’t really help that much. What would help, though, is increasing the reflectiveness of the city. That would lessen the amount of heat the city absorbs during the day and even help indirectly at night, by decreasing the amount of heat to be released after the sun goes down. Plus it’s easy—roofs can be painted white or roads can be paved ([pev] vt.鋪設pavement [`pevm1nt] n. [U] 鋪設過的路面) with light­colored concrete.

White roofs also present additional benefits, such as cutting down on energy use because less air conditioning would be needed to balance out (抵銷 (某物)，使 (某物) 相等) the heat absorbed by these buildings. What’s more, lowering energy use also means reducing carbon emissions ([I`mIS1n] n. [C]排放物emit [I`mIt] vt. (emitted | emitted | emitting) 散發，發出). Best of all, the implementation ([&Impl1mEn`teS1n] n. [U]實施，執行implement [`Impl1&mEnt] vt. 實施，執行) of white roofs requires the least amount of investment ([In`vEstm1t] n. [U]投資invest [In`vEst] vt. 投資) for the most immediate return.

—Adapted from “Why the City Is (Usually) Hotter than the Countryside.”

Comprehension Check

Choose the correct answer to each question or statement.

(　　) 1. The main purpose of the reading is to ________.

(A) encourage city dwellers to move to rural regions

(B) explain how the UHI effect causes health problems

(C) advise people not to purchase or use air conditioners

(D) illustrate what causes higher temperatures in urban areas

(　　) 2. Which of the following is NOT a reason why urban temperatures tend to be higher?

(A) Thin vegetation.

(B) Low humidity.

(C) Weak evaporation.

(D) Inefficient convection.

(　　) 3. According to the reading, which of the following statements is true?

(A) Efficient convection usually leads to the rapid dispersion of heat.

(B) The reflectiveness of a city has nothing to do with the UHI effect.

(C) White roofs and light­colored roads increase the amount of heat that is absorbed.

(D) Reducing the heat from human activities could completely solve the UHI problem.

Word File

I. Common Household Appliances
air conditioner 冷氣機	fax machine 傳真機		water dispenser 飲水機		coffee maker 咖啡壺
steam iron 蒸氣電熨斗	printer 印表機		microwave 微波爐		vacuum 吸塵器
II. Common Building Materials
concrete　混凝土		brick　磚頭		marble　大理石
cement　水泥		tile　磁磚		timber　木材

Patterns in Use

1  No other + N1 + be/V + as + adj./adv. + as + N2 Examples: ‧No other places on Earth seem to be as hot as cities in summer. ‧No other student in my class can run as fast as Leo. ‧No other thing is as important as health.

Exercise:

Rewrite the following sentences by using the above pattern. The first one has been done for you.

1. Mount Everest is the highest mountain in the world.

→ No other mountain in the world is/mountains in the world are as high as Mount Everest.

2. Elia Kazan was perhaps the most influential director in the film industry.

→ ___________________________________________________________________________

3. For the shy girl, public speaking is the most frightening thing.

→ ___________________________________________________________________________

4. The Hunger Games is the sci­fi series that interests me the most.

→ ___________________________________________________________________________

5. Christine was the person who sang most beautifully in the singing contest.

→ ___________________________________________________________________________

2  No matter how­/what­/who­/when­/where­/which­clause, S + be/V . . . Examples: ‧No matter what the local climate is, the release of heat stored up during the day creates a heat island effect. ‧No matter how difficult the task is, I will never give up. ‧No matter where you go, you have to let your parents know.

◎Exercise:

Complete the following passage about the UHI effect by using the above pattern. The first one has been done for you.

As urban areas develop, buildings, roads, and other structures usually replace open land and plants. These changes cause urban regions to become warmer than their rural surroundings, forming an “island” of higher temperatures in the landscape. However, ¹__no matter how serious the UHI effect is__ (how serious/UHI effect/be), certain strategies can be used to address the situation. First, by planting more trees in the city, air temperatures can be lowered because of evapotranspiration (蒸散). ²________________________ (what kind of tree/be/plant), they will help reduce urban heat.

As for those people who want to stay indoors, air conditioning doesn’t offer a good long­term solution, ³________________________ (how low/temperature/be/set). One good way to deal with this problem is to install green roofs or rooftop gardens, since the surface temperature of a green roof will be cooler than the air temperature. Another good way is to install cool roofs, which are made of materials that can reflect sunlight. With cool roofs, ⁴________________________ (how brightly/sun/shine), cool roofs will help to reflect sunlight and keep the heat away.

In addition, cool pavements are also helpful in reducing the UHI effect. Paving technologies include the use of existing materials, such as asphalt (柏油) and concrete, and new approaches, such as the use of coatings and grass paving. ⁵________________________ (how much/material/cost), those materials that can reflect more sunlight should always be the top choice. By means of such strategies, the UHI effect could be reduced to some degree.

◎Extra Exercise:

Translate the following pairs of Chinese sentences into English by using the patterns on pages 133 and 134.

I.

1. 無論我多晚回家，我爸媽都會為我等門。

→ __________________________________________________________________________

2. 世界上沒有其他人比他們更愛我。

→ __________________________________________________________________________

II.

1. 無論你吃什麼，你都應注意食材的來源。

→ __________________________________________________________________________

2. 畢竟，沒有其它事情比食品安全更重要。

→ __________________________________________________________________________

III.

1. 無論何時你發現有人需要幫助，你都應立即伸出援手。

→ __________________________________________________________________________

2. 沒有其他人比那些提供即刻援助的人更仁慈。

→ __________________________________________________________________________

Writing Hands-on

Classification: Part I

In a classification paragraph, the writer arranges people, things, or ideas into groups based on shared characteristics. It often features examples that are organized according to types, parts, or categories.

Brainstorm

Before writing a classification paragraph, you will first need to choose a topic broad enough to be divided into groups. After you decide on your topic, it should be arranged into subgroups according to their shared characteristics.

Examples:

classification topic causes of the UHI effect
↙	↓	↘
category 1 people	category 2 buildings	category 3 machinery

Exercise A:

Fill in the following blanks by dividing learners into three categories based on their shared characteristics.

classification topic types of learners
↙	↓	↘
category 1	category 2	category 3

Transitional words or phrases that are often used in a classification paragraph can be categorized as follows:

(A) Indicating addition:

first (of all), to begin with, first, second, third, following that, after that, then, lastly, finally, . . .

(B) Giving examples:

for example, for instance, . . .

Exercise B:

Complete the following classification paragraph with a proper transitional word in the box below. The first one has been done for you.

to begin with

for example

second

lastly

Learners can be classified into three main types: auditory, visual, and physical, according to their different learning styles. ¹__To begin with__, there are auditory learners, who would rather listen to their learning materials than read them. They basically depend on listening to either a teacher or other forms of audio instruction to learn new things. ²________ , there are visual learners, who learn best through graphics, demonstrations, or reading. They rely on visual aids to learn effectively. ³________, they may use pictures, videos, or diagrams to help them process the information. ⁴________ , for physical learners, physically performing a process is the way to learn. They process information through “hands­on” experience. For this kind of students, learning by doing is the easiest way for them to learn.