Page 39 - 新思维科学学生用书9 样章

1 Photosynthesis and the carbon cycle

Questions

3 Look at the graph. How much higher was the mean temperature in 2016 than in 1880?
4 Describe the trend shown by the graph between:
• 1880 and 1910 and

• 1910 and 2016.

Impacts of climate change

More extreme weather events

We are already feeling the effects of this increase in temperature. The higher temperatures mean that

there is more energy in the atmosphere. This increases the chance of extreme weather events, such as
hurricanes and typhoons. Many scientists think that we are already seeing an increase in the number
of storms, and in their severity. It is difficult to be certain, because there has always been a lot of
variation each year in the number of big storms.

Tropical cyclone Idai hit the east coast of

southern Africa in 2019. It was one of the worst
storms ever to affect Africa and killed more than
1300 people. Severe flooding destroyed homes
and fields, damaging people’s livelihoods. Was

this a result of climate change? We cannot say,
because storms like this can happen anyway.
However, there seem to be more of them now,
and they are more violent.

Less predictable rainfall

The changing climate is also making it more
difficult for people in some parts of the world
to grow crops. Rains may come late, or might

not come at all. Or rain may fall when it doesn’t
normally fall – or fall much more heavily,
causing flooding.

Monsoon rains are usually welcomed, but not
when they are so heavy that they cause severe flooding. In 2019, the monsoon rains in Pakistan, India,

Nepal and Bangladesh came later and were heavier than usual. Millions of people in these countries
were affected by floods.

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