Concern over the weather associated with El Ni?o has increased interest in the possibility that the climate on Earth is getting warmer. The most common theory relates an increase in atmospheric levels of carbon dioxide (CO₂), a greenhouse gas, to increases in temperature. Here is a scatterplot showing the mean annual CO_2?concentration in the atmosphere, measured in parts per million (ppm) at the top of Mauna Loa in Hawaii, each year from 1959 to 2016, and the global annual mean temperature (in degrees Celsius [C] from meteorological stations across the globe). A regression predicting Mean Temperature from CO₂ produces the following output table (in part).

a) What is the correlation between CO₂ and Mean Temperature?

b) Explain the meaning of R-squared in this context.

c) Give the regression equation.

d) What is the meaning of the slope in this equation?

e) What is the meaning of the intercept of this equation?

f) Here is a scatterplot of the residuals vs. CO₂. Does this plot show evidence of the violations of any of the assumptions of the regression model? If so, which ones?

Transcribed Image Text:

15.0 + 14.5 + 14.0 + 320 340 360 380 400 C02 (ppm) Mean annual temperature (°C)