Article Type:
Research Article

A Striking Cloud Over Boulder, Colorado: What Is Its Altitude, and Why Does It Matter?

Margaret A. LeMone National Center for Atmospheric Research,* Boulder, Colorado

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Thomas W. Schlatter Cooperative Institute for Research in Environmental Sciences, University of Colorado, and NOAA Earth System Research Laboratory, Boulder, Colorado

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Robert T. Henson University Corporation for Atmospheric Research, Boulder, Colorado

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Online Publication:
01 Jun 2013
Print Publication:
01 Jun 2013
DOI:
https://doi.org/10.1175/BAMS-D-12-00133.1
Page(s):
788–797
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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.

CORRESPONDING AUTHOR: Margaret A. LeMone, National Center for Atmospheric Research, Boulder, CO 80307-3000, E-mail: lemone@ucar.edu

*NCAR is sponsored by the National Science Foundation

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.

CORRESPONDING AUTHOR: Margaret A. LeMone, National Center for Atmospheric Research, Boulder, CO 80307-3000, E-mail: lemone@ucar.edu

*NCAR is sponsored by the National Science Foundation

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Cover Bulletin of the American Meteorological Society
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