IELTS Reading — Stage 3 (4): The Concrete Furnace

Full passage, questions, and deep linguistic analysis in English.

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READING PASSAGE

The Concrete Furnace

A. On a July afternoon in Phoenix, Arizona, the asphalt on an airport taxiway reached a temperature of eighty-six degrees Celsius — hot enough to fry an egg and far above the air temperature of forty-four. This is not an anomaly. Cities around the world are warming faster than the rural land around them, a phenomenon known as the urban heat island effect. The cause is straightforward enough: concrete, asphalt, and brick absorb solar radiation during the day and release it slowly at night, while the trees and soil that would otherwise cool the surface have been paved over. What is less straightforward is why the effect is proving so stubborn to reverse.

B. The standard prescription for cooling a city has long been to plant more trees. Shade lowers surface temperature directly, and the water vapour released through a tree's leaves — a process called transpiration — has a further cooling effect on the surrounding air. Many cities have set ambitious tree-planting targets. Los Angeles, for example, pledged to plant a million new trees by 2030. But a 2022 audit found that only about a fifth of the target had been met, and many of the trees that were planted died within a few years, victims of heat stress and inadequate watering. The problem, urban foresters say, is that a sapling in a parking lot median receives a fraction of the water and soil that a tree in a forest does.

C. A second approach has been to paint rooftops and pavements white. Light-coloured surfaces reflect rather than absorb sunlight, a principle known as albedo modification. The idea is not new — ancient Greek settlements used whitewashed walls to stay cool — but it has recently been revived by engineers who calculate that a city-wide shift to high-albedo surfaces could lower peak temperatures by as much as two degrees. The catch is that reflective roofs solve only part of the problem. They cool the building they sit on, but they do nothing for the street level, where pedestrians actually experience the heat. Worse, reflected light can bounce off the ground and heat nearby walls, creating unintended glare.

D. The most ambitious proposal is to redesign streets themselves. Traditional urban planning treated roads as conduits for cars, and the resulting canyons — tall buildings on both sides of wide, dark roads — trap heat at street level. A growing number of cities are now experimenting with narrower roadways, more permeable surfaces that allow rainwater to soak in, and covered walkways that cast shade. Singapore, which has the highest urban heat intensity of any major city in the world, has invested heavily in what it calls "cool corridors": tree-lined, covered walkways that connect buildings and keep pedestrians in shade from dawn to dusk. The investment has been substantial, but the data so far suggests street-level temperatures have dropped by up to four degrees along the upgraded routes.

E. What complicates all these efforts is the mismatch between the scale at which heat is generated and the scale at which solutions are applied. A single green roof on one building is a gesture; a city needs thousands of them to move the needle. Yet the incentives are local. A homeowner who plants a tree benefits the immediate neighbourhood, but the financial cost falls on them alone. Municipal governments, which have the power to mandate changes, are often constrained by tight budgets and wary of angering voters who see new regulations as overreach. The result is a patchwork of well-meaning projects that rarely add up to the systemic change the problem requires.

F. None of this means the fight is lost. Phoenix itself has begun to show progress: a combination of shade structures over bus stops, mandatory cool-roof standards for new buildings, and a programme to replace asphalt playground surfaces with lighter materials has measurably reduced heat-related emergency calls. But city officials are candid about the limits of what they can achieve on their own. The urban heat island is, at bottom, a by-product of a global system that continues to warm. Local action, however innovative, can only soften the blow.

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QUESTIONS

Questions 1–4: Choosing Headings

Choose the correct heading for paragraphs B, C, D, and E.

i.	Why tree-planting has fallen short
ii.	How street redesign is changing urban heat
iii.	The history of whitewashed buildings
iv.	A reflection-based approach and its limits
v.	The economic cost of heat-related illness
vi.	Why individual actions do not add up
vii.	How Phoenix became the hottest city

1. Paragraph B ____ 2. Paragraph C ____ 3. Paragraph D ____ 4. Paragraph E ____

Questions 5–9: YES / NO / NOT GIVEN

5. The taxiway temperature in Phoenix was higher than the air temperature.

6. Los Angeles met its tree-planting target by 2022.

7. White reflective surfaces cool both rooftops and streets equally.

8. Singapore's cool corridors have reduced street-level temperatures.

9. Municipal governments always have sufficient funding for heat programmes.

Questions 10–13: Sentence Completion (NO MORE THAN TWO WORDS)

10. Trees cool the air through a process called ________.

11. Light-coloured surfaces reflect sunlight, a principle known as ________ modification.

12. Narrow roads and permeable surfaces are examples of how cities are redesigning their ________.

13. Local efforts can only ________ the effect of a globally warming climate.

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ANSWER KEY

Q	Answer	Q	Answer
1	i	8	YES
2	iv	9	NO
3	ii	10	transpiration
4	vi	11	albedo
5	YES	12	streets
6	NO	13	soften
7	NO

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DEEP LINGUISTIC ANALYSIS

A. Sentence Architecture

Paragraph A, key sentence:

What is less straightforward is why the effect is proving so stubborn to reverse.

• What is less straightforward — a nominal relative clause acting as the subject. It means "the thing that is less easy to understand."
• proving so stubborn to reverse — Prove here means "turns out to be." Stubborn is personified: the effect does not want to go away. This is a common journalistic personification.

Paragraph E, last sentence:

The result is a patchwork of well-meaning projects that rarely add up to the systemic change the problem requires.

• Patchwork — a metaphor: pieces of cloth sewn together unevenly. The projects are individual and disconnected.
• Well-meaning — hyphenated adjective. It sounds approving but carries a faint criticism: they have good intentions but not enough effect.
• Add up to — phrasal verb meaning "combine to produce." The projects don't accumulate into a real solution.

B. Vocabulary in Depth

anomaly (A) = something that deviates from what is expected. The record-breaking temperature is not an anomaly — it's becoming normal.

albedo (C, Q11) = the fraction of light reflected by a surface. From Latin albus (white). This is a technical term; you don't need to know it beforehand, but the text explains it.

the catch (C) = the hidden problem. Informal. The catch is that... = "but here's the limitation."

move the needle (E) = make a measurable difference. Metaphor from the gauge needle on a measuring instrument.

overreach (E) = exceeding legitimate authority. Voters see new regulations as government overreach.

by-product (F) = an unintended side effect. The heat island is not the goal of urban development; it's a by-product.

C. Logical Signposts

Phrase	Effect
What is less straightforward is...	Signals complexity ahead.
The catch is that...	Introduces a limitation or problem.
What complicates all these efforts is...	Signals a structural obstacle, not a technical one.
None of this means the fight is lost.	Pivot: the paragraph moves to cautious optimism.

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