# Exploration 3A

## Temperature Trends over Recent Decades Compared to the Past 125 Years

In the previous exploration, you estimated the trend line for the past 125 years. You also used linear regression to calculate the slope for the past 125, 100, 75, 50 and 25 years, and you graphed the trend lines for 125 years and 25 years. Now you use the interactive time-series graphing tool to view the trend lines for these same time periods.

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## Trend Lines For the past 125 Years

- Click on the button for 125 years. How much does this slope differ from the one that you estimated in Part B of Exploration 2.
- Click on the buttons for the 100-, 75-, 50-, and 25-year time intervals. How do your observations compare to the slopes of the trend lines that you calculated using linear regression in the previous exploration?
- What do you observe about the slopes of the trend lines for each time interval? ending temperature anomalies. Enter these values in the table.