Lab 2 - Global Average Temperature PART 2

YEAR YEARLY AVERAGE T SUMMER AVERAGE T WINTER AVERAGE T

 Task 3:  Make a chart of annual temperature vs. time for the years 1880- 2005 and calculate its slope and intercept using MS Excel Recall: Highlight data you want Insert  Scatter Design  Quick Layout  f(x) layout with equation Add axis labels and title

 Task 3:  Make a chart of annual temperature vs. time for the years 1880- 2005 and calculate its slope and intercept using MS Excel Recall: Highlight data you want Insert  Scatter Design  Quick Layout  f(x) layout with equation Add axis labels and title

How would you describe the general appearance of this curve How would you describe the general appearance of this curve? Describe the major features of the global temperature time series. (What do the high and low points describe?) Which direction is the slope of the line of best fit? What does this mean, physically? Interpret the r-squared value. How much warming has occurred over the entire time series?  Take the difference of the biggest number minus the smallest number in the y- direction. This is the highest temperature minus the lowest temperature. FIGURE 1

a) What does the slope of a line represent? 3. Now make a chart of annual temperature vs. time for only the years 1975- 2005.  a) What does the slope of a line represent? b) Find the formula of a line. Write down the equation. According to this equation, what is the value of "m"? What is the value of "b"? c) Sketch a graph with a slope showing the following relationships: (1) as x increases y increases. (2) as x increases y decreases. (3) no change in y as x increases. This is an example of an “as x increases, y increases” relationship FIGURE 2 y=mx+b y: vertical axis data (temperature) x: horizontal axis data (year) m: slope b: y intercept

4. How does the slope in the chart of annual temperature vs 4. How does the slope in the chart of annual temperature vs. time compare to the 1867-2006 curve?  FIGURE 1 FIGURE 2

5. As you saw in previous weeks, carbon dioxide and other greenhouse gases have been increasing in concentration over the 20th Century. Discuss what this has to do with the temperature time series you examined this week.  6. Is CO2 a perfect global temperature predictor?

For the following, consult the data & graphs you created: 7. What are the 5 warmest years in the record? The 5 coldest?   8. Have we come anywhere close to having one of the coldest years in the record during your lifetime?  9. How long a record is needed to see clear evidence of global warming? Why? FIGURE 1 FIGURE 2