Extended Data Fig. 5. Changes to Nd and albedo can be detected in a small region after only one and four months, respectively.
Shown is the fraction of significant anomalies for albedo and Nd as a function of the number of days studied. This is for the Chilean Sc described above. For a given number of days n, 20 samples of n days are drawn from the total observation period and anomalies are calculated. This is to emulate a random draw of observation days. Anomalies are taken to be significant if they are larger than two standard errors, equivalent to a Student’s t-test at 95% confidence. We assume that we are able to make a confident detection if in 95% of draws, so 19 out of 20, we observe significant anomalies.