Description
Return a one-layer potential-vorticity term.
Atmospheric dynamics uses signed coordinates, rotating-flow approximations, fluctuation definitions and stability conventions. One advection, shear, vorticity or wave term omits parts of the full equations and need not establish the state or stability of an observed atmosphere.
Return a one-layer potential-vorticity term.
When to use this tool
Use Potential Vorticity One Layer Term when evaluating the stated local atmospheric dynamic, turbulence, stability or wave term.
How to use the tool and how it works
- Enter gravity, coriolis, relativeVorticity, upperTheta, lowerTheta, pressureThickness. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read absoluteVorticity, potentialVorticity. Use the output convention below.
Return a one-layer potential-vorticity term. Require gravity/pressureThickness > 0; absoluteVorticity = coriolis+relativeVorticity, PV = gravity*absoluteVorticity*(upperTheta-lowerTheta)/pressureThickness.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| gravity | Gravity | Required. Finite number; strictly above 0. |
| coriolis | Coriolis | Required. Finite number. |
| relativeVorticity | Relative Vorticity | Required. Finite number. |
| upperTheta | Upper Theta | Required. Finite number. |
| lowerTheta | Lower Theta | Required. Finite number. |
| pressureThickness | Positive lower-pressure minus upper-pressure thickness, in Pa for coherent SI PV. | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| absoluteVorticity | Absolute Vorticity | Required. Finite number. |
| potentialVorticity | Local SI-like term under supplied units; multiply coherent SI values by 10^6 separately for PVU. | Required. Finite number. |
{
"input": {
"gravity": 10,
"coriolis": 0.0001,
"relativeVorticity": 0.00002,
"upperTheta": 310,
"lowerTheta": 300,
"pressureThickness": 10000
},
"output": {
"absoluteVorticity": 0.00012,
"potentialVorticity": 0.0000012
}
}Limitations and assumptions
- Pressure thickness uses the positive lower-minus-upper convention; horizontal gradient terms are omitted and output is not automatically scaled to PVU.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use complete verified fields and an appropriate dynamical model, including coordinate directions, omitted terms and approximation validity, for physical or forecast interpretation.
References
Similar or alternative tools
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