Description
Calculate a nominal dry-air column mass from supplied pressure bounds.
Atmospheric values depend on pressure order, vertical datums, moisture definitions and reference conditions. Specific humidity uses moist-air mass as its denominator, whereas mixing ratio uses dry-air mass. A pressure-order flag differs from a temperature inversion, and a logarithmic-pressure weight can represent extrapolation.
Calculate a nominal dry-air column mass from supplied pressure bounds.
When to use this tool
Use Atmospheric Column Layer Dry Mass when you already have bottomPressurePascals, topPressurePascals, suppliedGravity, waterMassFraction and need to calculate a nominal dry-air column mass from supplied pressure bounds.
How to use the tool and how it works
- Enter bottomPressurePascals, topPressurePascals, suppliedGravity, waterMassFraction. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read dryMassKilogramsPerSquareMeter. Use the output convention below.
Require bottomPressure>=topPressure>=0, suppliedGravity>0 and waterMassFraction in [0,1]; return (bottom-top)/gravity*(1-water fraction).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| bottomPressurePascals | Bottom Pressure Pascals | Required. Finite number. |
| topPressurePascals | Top Pressure Pascals | Required. Finite number; minimum 0. |
| suppliedGravity | Positive acceleration in m/s² for the stated kg/m² output. | Required. Finite number; strictly above 0. |
| waterMassFraction | Bulk water mass/total layer mass, dimensionless in [0,1]. | Required. Finite number; minimum 0; maximum 1. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| dryMassKilogramsPerSquareMeter | Dry Mass Kilograms Per Square Meter | Required. Finite number. |
{
"input": {
"bottomPressurePascals": 100000,
"topPressurePascals": 90000,
"suppliedGravity": 10,
"waterMassFraction": 0.01
},
"output": {
"dryMassKilogramsPerSquareMeter": 990
}
}Limitations and assumptions
- Pressure is Pa and gravity m/s² for kg/m². This uses hydrostatic column mass and a supplied bulk water mass fraction; it does not resolve vertical humidity, suspended water or nonhydrostatic effects.
- 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 calibrated profile and station data with the complete atmospheric model. Preserve datum, humidity and pressure conventions and assess uncertainty before interpreting local terms as an observed layer, state or forecast.
References
Similar or alternative tools
- Virtual Temperature Single Humidity Factor
Apply a supplied dry/vapor gas-constant ratio to virtual temperature.
- Pressure Level Log Interpolation Weight
Calculate a supplied logarithmic-pressure interpolation coordinate.