How to use this lesson

Passage Concept Pattern Example

"Dark roofs make the air above them hotter in summer."

Why this works: Dark roofing materials absorb solar energy rather than reflecting it, raising local surface and surrounding air temperatures.

Reading Passage

The U.S. Environmental Protection Agency, or EPA, says that cities are warmer than the land around them. It says that in the United States, daytime temperatures in cities are about 1 to 7 degrees Fahrenheit higher than outside them, and night temperatures are about 2 to 5 degrees higher.

The EPA says that roads and roofs take in heat and give it out more than most natural surfaces do. It says that on a warm day, ordinary roofing can get as much as 66 degrees Fahrenheit warmer than the air around it. It also says that green roofs can help cities with little greenery, especially during the day.

The City of Toronto in Canada made a Green Roof Bylaw in 2009. The rule covers new buildings, starting at 2,000 square metres of floor area. The bigger the building, the larger the part of the roof that must be green, from 20 percent to 60 percent. Toronto says that from 2010 to 2025 the bylaw helped to build more than 1,200 green roofs.

The writer's own cautious view, hedged ("I think", "it seems"): I think the EPA figures show why dark roofs make a city uncomfortable, but it seems that they are ranges for the United States, so they may not fit every city. Toronto counts green roofs and not degrees, so I do not think its number tells us how much cooler the city has become.

Yes / No / Not Given

1. In the United States, urban locations experience higher temperatures at night compared to surrounding non-urban land.

2. Toronto was the first city in North America to enact a mandatory green roof regulation for large buildings.

Multiple Choice

3. According to paragraph B, how hot can conventional roof surfaces get compared to surrounding air on warm days?

4. What condition determines whether a building must comply with Toronto's 2009 Green Roof Bylaw?

5. Which statement best summarizes the writer's view regarding Toronto's reported 1,200 green roofs?

Matching Information

6. Comparative temperature data contrasting daytime urban heat increases with night-time increases.

7. Details on how required green roof coverage scales according to building size.

Summary Completion

Urban Heat and Mitigation Bylaws

According to the EPA, urban roads and roofs retain heat more than natural terrain. On warm days, standard roofing can become up to ____ degrees Fahrenheit warmer than ambient air.

To address limited urban greenery, the City of Toronto established a regulatory rule targeting ____ buildings starting at 2,000 square metres of floor space.

However, the writer points out that because Toronto tallies the count of installed green roofs rather than actual ____ , the exact reduction in urban temperature remains unconfirmed.