Albedo of ice melt ponds. Refer to the National Snow and Ice Data Center (NSIDC) collection of data on the albedo, depth, and physical characteristics of ice-melt ponds in the Canadian Arctic, presented in Exercise 2.13 (p. 35). Albedo is the ratio of the light reflected by the ice to that received by it. (High albedo values give a white appearance to the ice.) Visible albedo values were recorded for a sample of 504 ice-melt ponds located in the Barrow Strait in the Canadian Arctic; these data are saved in the PONDICE file.
a. Find a 90% confidence interval for the true mean visible albedo value of all Canadian Arctic ice ponds.
b. Give both a practical and a theoretical interpretation of the interval.
c. Recall from Exercise 2.13 that the type of ice for each pond was classified as first-year ice, multiyear ice, or land fast ice. Find 90% confidence intervals for the mean visible albedo for each of the three types of ice. Interpret the intervals.
Characteristics of ice melt ponds. The National Snow and Ice Data Center (NSIDC) collects data on the albedo, depth, and physical characteristics of ice melt ponds in the Canadian Arctic. Environmental engineers at the University of Colorado are using these data to study how climate affects the sea ice. Data on 504 ice melt ponds located in the Barrow Strait in the Canadian Arctic are saved in the PONDICE file. One variable of interest is the type of ice observed for each pond, classified as first year ice, multiyear ice, or land fast ice. An SAS summary table and a horizontal bar graph that describe the types of ice of the 504 melt ponds are shown at the bottom of page 35.
a. Of the 504 melt ponds, what proportion had land fast ice?
b. The University of Colorado researchers estimated that about 17% of melt ponds in the Canadian Arctic have first-year ice. Do you agree?
c. Convert the horizontal bar graph into a Pareto diagram. Interpret the graph.