Snow Water Equivalent One Layer Term Tool

Description

Multiply nonnegative snowDepth by snowDensity/positive waterDensity for solidWaterEquivalent and add nonnegative liquidWaterDepth.

Snow water equivalent expresses stored water as a depth using snow thickness and density. Layer accounting and liquid-water assumptions matter because separately included components can otherwise be counted twice.

Multiply nonnegative snowDepth by snowDensity/positive waterDensity for solidWaterEquivalent and add nonnegative liquidWaterDepth.

When to use this tool

Use Snow Water Equivalent One Layer Term when you need one supplied snow-storage or water-equivalent component.

How to use the tool and how it works

Enter snowDepth, snowDensity, waterDensity, liquidWaterDepth. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read solidWaterEquivalent, totalWaterEquivalent. Use the output convention below.

Multiply nonnegative snowDepth by snowDensity/positive waterDensity for solidWaterEquivalent and add nonnegative liquidWaterDepth.^[1]

Input field	Meaning and units	Accepted input
snowDepth	Snow Depth	Required. Finite number; minimum 0.
snowDensity	Snow Density	Required. Finite number; minimum 0.
waterDensity	Water Density	Required. Finite number; strictly above 0.
liquidWaterDepth	Liquid Water Depth	Required. Finite number; minimum 0.

Output field	Interpretation	Returned shape
solidWaterEquivalent	Solid Water Equivalent	Required. Finite number.
totalWaterEquivalent	Total Water Equivalent	Required. Finite number.

json

{
  "input": {
    "snowDepth": 0.5,
    "snowDensity": 300,
    "waterDensity": 1000,
    "liquidWaterDepth": 0.02
  },
  "output": {
    "solidWaterEquivalent": 0.15,
    "totalWaterEquivalent": 0.16999999999999998
  }
}

Limitations and assumptions

Densities share units and all depths share units. If snowDensity already includes liquid water, adding liquidWaterDepth can double count it; the component basis must be supplied consistently.
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

Review the sampling method, density basis, layer structure, and complete snow-process model before estimating available water.

References

Calculation and input contract: hydrometeorology/snow-water-equivalent-one-layer-term — tool.io

Similar or alternative tools

Snowpack Layer Water Ratio
Sum layer thicknesses and thickness times snow/water density ratio; divide equivalent depth by snow depth or return zero with defined false.
Snow Core Water Mass Factor
Divide nonnegative waterMass by positive coreArea and waterDensity for waterEquivalentDepth.