Earth & climate · the experiment
Turn IceCube into a thermometer
Under the South Pole, IceCube counts muons whose number follows the temperature of the stratosphere. Unmask what could fool this thermometer, then find how many years it takes to read the cooling.
1 · A drift in disguise
Beginner
For purely instrumental reasons, IceCube's muon count slowly falls, decade after decade. What does the analysis read?
The slider starts at a fall of 1% per decade. Set it so that the fake cooling is as large as the cooling observed since 2011.
2 · Snow joins in
Intermediate
Snow piling up above IceCube lowers the count by 0.087 to 0.181% per decade. A fall of 1% per decade mimics 2.8 K per decade. How much fake cooling does the snow produce, at most?
3 · How many years?
Intermediate
After 20 years of data, the statistical sensitivity falls to 0.93 K per decade. The cooling observed since 2011 is about 0.9 K per decade. Is it confirmed at 95%?
Lengthen the record, year by year. Find the shortest length that confirms the cooling observed since 2011.
4 · Forty years of patience
Expert
A detector's count falls by 0.3% per decade without anyone knowing. After 40 years, the statistical sensitivity is 0.33 K per decade. If the stratosphere does not change at all, what trend per decade does the analysis report?
Thermometer calibrated
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