Reply to “Comments on ‘MSE minus CAPE is the True Conserved Variable for an Adiabatically Lifted Parcel’”

Romps, David M.

doi:10.1175/JAS-D-15-0334.1

Title: Reply to “Comments on ‘MSE minus CAPE is the True Conserved Variable for an Adiabatically Lifted Parcel’”

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Abstract

A standard convention in moist thermodynamics, adopted by D. M. Romps and others, is to set the specific energy and entropy of dry air and liquid water to zero at the triple-point temperature and pressure. P. Marquet claims that this convention leads to physically incorrect results. To support this claim, Marquet presents numerical calculations of a lifted parcel. It is shown here that the claim is false and that the numerical calculations of Marquet are in error. In the context of a simple two-phase thermodynamic system, an analysis is presented here of the freedoms one has to choose additive constants in the definitions of energy and entropy. Many other misconceptions are corrected as well.

Authors:

Romps, David M. ^[1]

Univ. of California, Berkeley, CA (United States). Dept. of Earth and Planetary Science; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Climate and Ecosystem Sciences Division

Publication Date:: Mon Jun 13 00:00:00 EDT 2016

Research Org.:: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Biological and Environmental Research (BER)

OSTI Identifier:: 1471016

Grant/Contract Number:: AC02-05CH11231

Resource Type:: Accepted Manuscript

Journal Name:: Journal of the Atmospheric Sciences

Additional Journal Information:: Journal Volume: 73; Journal Issue: 6; Journal ID: ISSN 0022-4928

Publisher:: American Meteorological Society

Country of Publication:: United States

Language:: English

Subject:: 54 ENVIRONMENTAL SCIENCES; Physical Meteorology and Climatology; Energy budget/balance; Entropy; Thermodynamics

Citation Formats


                    Romps, David M. Reply to “Comments on ‘MSE minus CAPE is the True Conserved Variable for an Adiabatically Lifted Parcel’”.  United States: N. p., 2016. 
Web.  doi:10.1175/JAS-D-15-0334.1.

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                    Romps, David M. Reply to “Comments on ‘MSE minus CAPE is the True Conserved Variable for an Adiabatically Lifted Parcel’”.  United States.  https://doi.org/10.1175/JAS-D-15-0334.1

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                    Romps, David M. Mon .  
"Reply to “Comments on ‘MSE minus CAPE is the True Conserved Variable for an Adiabatically Lifted Parcel’”".  United States.  https://doi.org/10.1175/JAS-D-15-0334.1.  https://www.osti.gov/servlets/purl/1471016.

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@article{osti_1471016,

  title        = {Reply to “Comments on ‘MSE minus CAPE is the True Conserved Variable for an Adiabatically Lifted Parcel’”},

  author       = {Romps, David M.},

  abstractNote = {A standard convention in moist thermodynamics, adopted by D. M. Romps and others, is to set the specific energy and entropy of dry air and liquid water to zero at the triple-point temperature and pressure. P. Marquet claims that this convention leads to physically incorrect results. To support this claim, Marquet presents numerical calculations of a lifted parcel. It is shown here that the claim is false and that the numerical calculations of Marquet are in error. In the context of a simple two-phase thermodynamic system, an analysis is presented here of the freedoms one has to choose additive constants in the definitions of energy and entropy. Many other misconceptions are corrected as well.},

  doi          = {10.1175/JAS-D-15-0334.1},

  journal      = {Journal of the Atmospheric Sciences},

  number       = 6,

  volume       = 73,

  place        = {United States},

  year         = {Mon Jun 13 00:00:00 EDT 2016},

  month        = {Mon Jun 13 00:00:00 EDT 2016}

}

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https://doi.org/10.1175/JAS-D-15-0334.1

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