CIN Convective Inhibition

Integrate only negative caller parcel virtual-buoyancy segments in bounded observed window, retaining signed CIN and magnitude; boundary choices/parcel lift are caller declared, not inferred complete sounding inhibition.

Description

Convective inhibition is the negative buoyancy contribution opposing parcel ascent through a declared layer.

Convective inhibition is the negative buoyancy contribution opposing parcel ascent through a declared layer. Integrating only negative parts preserves its sign and separates it from positive CAPE.^{[1, 2]}

When to use CIN Convective Inhibition

Use this tool to integrate only negative caller parcel virtual-buoyancy segments in bounded observed window, retaining signed CIN and magnitude; boundary choices/parcel lift are caller declared, not inferred complete sounding inhibition.

Prepare the observed sounding, cloud records or forecast verification data. Check pressure and height coordinates, wind conventions and the stated units.

How to use CIN Convective Inhibition and understand its results

Prepare the observed sounding, cloud records or forecast verification data. Check pressure and height coordinates, wind conventions and the stated units.
Enter heightsM, parcelVirtualTemperaturesK, environmentVirtualTemperaturesK, gravityMPerSecondSquared, integrationBottomM, integrationTopM using the field table and calculation rules, then run the tool.
Read signedConvectiveInhibitionJPerKg, inhibitionMagnitudeJPerKg. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
heightsM	Heights m	list of number	Required
parcelVirtualTemperaturesK	Parcel virtual temperatures k	list of number	Required
environmentVirtualTemperaturesK	Environment virtual temperatures k	list of number	Required
gravityMPerSecondSquared	Gravity m per second squared	number	Required
integrationBottomM	Integration bottom m	number	Required
integrationTopM	Integration top m	number	Required

Enter positive aligned parcel/environment virtual Kelvin temperatures, positive gravity, increasing heights and ordered integration bounds within observed coverage. Interpolate boundary buoyancies and resolve linear zero crossings. Return signed nonpositive CIN and its nonnegative magnitude in J/kg.

buoyancy = g(Tvirtual parcel−Tvirtual environment)/Tvirtual environment; signed CIN = ∫min(buoyancy,0) dz

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
signedConvectiveInhibitionJPerKg	Signed convective inhibition j per kg	number
inhibitionMagnitudeJPerKg	Inhibition magnitude j per kg	number

json

{
  "input": {
    "heightsM": [
      0,
      1000,
      2000
    ],
    "parcelVirtualTemperaturesK": [
      270,
      300,
      330
    ],
    "environmentVirtualTemperaturesK": [
      300,
      300,
      300
    ],
    "gravityMPerSecondSquared": 10,
    "integrationBottomM": 0,
    "integrationTopM": 2000
  },
  "output": {
    "signedConvectiveInhibitionJPerKg": -500,
    "inhibitionMagnitudeJPerKg": 500
  }
}

Limitations and assumptions

Parcel trajectories and integration boundaries are supplied. Unsampled inhibition is not inferred.

Numeric inputs and returned numeric values must be finite; an unrepresentable returned value produces an error. Numeric lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use CAPE Convective Available Potential Energy: Integrate positive portions of caller precomputed virtual parcel/environment buoyancy in observed height window, resolving each linear zero crossing; no hidden parcel lift, full sounding CAPE outside coverage or storm safety. For a complementary task, use Cap Strength CIN Checker: Audit maximum measured environmental-minus-parcel cap temperature excess and location against caller threshold; not integrated CIN or proof that convection cannot occur.

Further background: Convective inhibition.

References

CIN Convective Inhibition — tool.io
Convective inhibition — National Weather Service

Similar or alternative tools

CAPE Convective Available Potential Energy
Integrate positive portions of caller precomputed virtual parcel/environment buoyancy in observed height window, resolving each linear zero crossing; no hidden parcel lift, full sounding CAPE outside coverage or storm safety.
Cap Strength CIN Checker
Audit maximum measured environmental-minus-parcel cap temperature excess and location against caller threshold; not integrated CIN or proof that convection cannot occur.