Convective inhibition: Difference between revisions
From Glossary of Meteorology
Line 9: | Line 9: | ||
<div class="definition"><div class="short_definition">(Abbreviated CIN or CINH.) The energy needed to lift an air parcel upward adiabatically to the [[lifting condensation level]] (LCL) and then as a [[Pseudoadiabatic_process|pseudoadiabatic process]] from the LCL to its level of free convection (LFC).</div><br/> <div class="paragraph">For an air parcel possessing positive [[convective available potential energy|CAPE]], the CIN represents the negative area on a [[thermodynamic diagram]]. The negative area typically arises from the presence of a [[lid]], or the amount of kinetic energy that must be added to a parcel to enable that parcel to reach the LFC. Even though other factors may be favorable for [[development]] of [[convection]], if convective inhibition is sufficiently large, deep convection will not form. The convective inhibition is expressed (analogously to CAPE) as follows:<div class="display-formula"><blockquote>[[File:CIN_equation.png|link=|center|CIN equation]]</blockquote></div>where ''p<sub>i</sub>'' is the pressure at the level at which the parcel originates, ''p<sub>f</sub>'' is the pressure at the LFC, ''R<sub>d</sub>'' is the [[specific]] gas constant for [[dry air]], ''T<sub>υp</sub>'' is the [[virtual temperature]] of the lifted parcel, and ''T<sub>υe</sub>'' is the virtual temperature of the [[environment]]. It is assumed that the environment is in [[hydrostatic balance]] and that the pressure of the parcel is the same as that of the environment. [[Virtual temperature]] is used for the parcel and environment to account for the effect of moisture on air density. | <div class="definition"><div class="short_definition">(Abbreviated CIN or CINH.) The energy needed to lift an air parcel upward adiabatically to the [[lifting condensation level]] (LCL) and then as a [[Pseudoadiabatic_process|pseudoadiabatic process]] from the LCL to its level of free convection (LFC).</div><br/> <div class="paragraph">For an air parcel possessing positive [[convective available potential energy|CAPE]], the CIN represents the negative area on a [[thermodynamic diagram]]. The negative area typically arises from the presence of a [[lid]], or the amount of kinetic energy that must be added to a parcel to enable that parcel to reach the LFC. Even though other factors may be favorable for [[development]] of [[convection]], if convective inhibition is sufficiently large, deep convection will not form. The convective inhibition is expressed (analogously to CAPE) as follows:<div class="display-formula"><blockquote>[[File:CIN_equation.png|link=|center|CIN equation]]</blockquote></div>where ''p<sub>i</sub>'' is the pressure at the level at which the parcel originates, ''p<sub>f</sub>'' is the pressure at the LFC, ''R<sub>d</sub>'' is the [[specific]] gas constant for [[dry air]], ''T<sub>υp</sub>'' is the [[virtual temperature]] of the lifted parcel, and ''T<sub>υe</sub>'' is the virtual temperature of the [[environment]]. It is assumed that the environment is in [[hydrostatic balance]] and that the pressure of the parcel is the same as that of the environment. [[Virtual temperature]] is used for the parcel and environment to account for the effect of moisture on air density. | ||
<br/> | |||
''Compare'' [[convective available potential energy]]. | ''Compare'' [[convective available potential energy]]. | ||
</div><br/> </div> | </div><br/> </div> | ||
<p>''Term updated | <p>''Term updated 4 December 2020.''</p> | ||
{{TermIndex}} | {{TermIndex}} |
Latest revision as of 05:10, 4 December 2020
convective inhibition[edit | edit source]
(Abbreviated CIN or CINH.) The energy needed to lift an air parcel upward adiabatically to the lifting condensation level (LCL) and then as a pseudoadiabatic process from the LCL to its level of free convection (LFC).
For an air parcel possessing positive CAPE, the CIN represents the negative area on a thermodynamic diagram. The negative area typically arises from the presence of a lid, or the amount of kinetic energy that must be added to a parcel to enable that parcel to reach the LFC. Even though other factors may be favorable for development of convection, if convective inhibition is sufficiently large, deep convection will not form. The convective inhibition is expressed (analogously to CAPE) as follows:where pi is the pressure at the level at which the parcel originates, pf is the pressure at the LFC, Rd is the specific gas constant for dry air, Tυp is the virtual temperature of the lifted parcel, and Tυe is the virtual temperature of the environment. It is assumed that the environment is in hydrostatic balance and that the pressure of the parcel is the same as that of the environment. Virtual temperature is used for the parcel and environment to account for the effect of moisture on air density.
Term updated 4 December 2020.