Key Idea.
Section 1
Data Reveals Long-Term Trends
When studying climate, it is vital to distinguish between a trend and a fluctuation. A trend is the general direction data moves over a long period, like a line sloping up or down.
Fluctuations are the zig-zags along that line—the short-term ups and downs. Confusing a yearly fluctuation with a long-term trend can lead to incorrect conclusions about the climate.
Section 2
Global Temperature Shows a Warming Trend
Looking at Earth's temperature data since 1880, we see many yearly fluctuations. Some years are hotter, some are cooler.
However, the underlying pattern is a clear upward trend. The global average temperature has been steadily rising for over a century, proving that the planet is warming despite occasional cold years.
Section 3
Earth's Ice Cover Shrinks Over Time
The cryosphere (ice) tells a similar story. While ice melts in summer and freezes in winter (fluctuation), the long-term data shows a decreasing trend.
Year after year, the total ice cover on Earth is getting smaller. This consistent loss of ice is independent evidence that confirms the warming trend seen in temperature data.
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Section 1
Data Reveals Long-Term Trends
When studying climate, it is vital to distinguish between a trend and a fluctuation. A trend is the general direction data moves over a long period, like a line sloping up or down.
Fluctuations are the zig-zags along that line—the short-term ups and downs. Confusing a yearly fluctuation with a long-term trend can lead to incorrect conclusions about the climate.
Section 2
Global Temperature Shows a Warming Trend
Looking at Earth's temperature data since 1880, we see many yearly fluctuations. Some years are hotter, some are cooler.
However, the underlying pattern is a clear upward trend. The global average temperature has been steadily rising for over a century, proving that the planet is warming despite occasional cold years.
Section 3
Earth's Ice Cover Shrinks Over Time
The cryosphere (ice) tells a similar story. While ice melts in summer and freezes in winter (fluctuation), the long-term data shows a decreasing trend.
Year after year, the total ice cover on Earth is getting smaller. This consistent loss of ice is independent evidence that confirms the warming trend seen in temperature data.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter