4 How can we slow down global warming?
Humans use large amounts of fuels like gas and oil, and release large amounts of greenhouse gases like carbon dioxide. This blocks the heat from releasing from the Earth’s surface and causes a rise in the Earth’s temperature.
1. In the past hundreds of thousands of years, there had only been small changes in the amount of carbon dioxide in the Earth’s atmosphere. Why has the amount increased sharply in the past one hundred years?
Carbon dioxide content in the Earth’s atmosphere in the past 800000 years
Amount of carbon dioxide in the atmosphere (parts per million)
420 380 340 300 260 220 180 420 380 340 300 260 220 180
現今 Now 1958 1958 1911 1911
8070605040302010 0
萬年前 800 700 600 500 400 300 200 100 0
thousands of years ago
Source: The National Aeronautics and Space Administration website
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industrial development
transportation
deforestation
bushfires
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