A striking cloud over Boulder, Colorado: What is its altitude, and why does it matter?

Scientific investigation is supposed to be objective and strictly logical, but this is not always the case: the process that leads to a good conclusion can be messy. This narrative describes interactions among a group of scientists trying to solve a simple problem that had scientific implications. It started with the observation of a cloud exhibiting behavior associated with supercooled water and temperatures around −20°C. However, other aspects of the cloud suggested an altitude where the temperature was around −40°C. For several months following the appearance of the cloud on 23 March 2011, the people involved searched for evidence, formed strong opinions, argued, examined evidence more carefully, changed their minds, and searched for more evidence until they could reach agreement. While they concluded that the cloud was at the higher and colder altitude, evidence for supercooled liquid water at that altitude is not conclusive.

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Author Lemone, Margaret
Schlatter, Thomas
Henson, Robert
Publisher UCAR/NCAR - Library
Publication Date 2013-06-01T00:00:00
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Topic Category geoscientificInformation
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Metadata Date 2023-08-18T18:20:43.706336
Metadata Record Identifier edu.ucar.opensky::articles:12732
Metadata Language eng; USA
Suggested Citation Lemone, Margaret, Schlatter, Thomas, Henson, Robert. (2013). A striking cloud over Boulder, Colorado: What is its altitude, and why does it matter?. UCAR/NCAR - Library. http://n2t.net/ark:/85065/d75b03bv. Accessed 21 April 2025.

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