Accumulated Freezing Degree Days Calculator
ObservedzeroC freezing indexdegree-daysmean-threshold,not max/mindaycomputationsor Stefanice-growth forecast. Actual independent units,calibration,measurement definitions/coverage and model applicability;not a climate forecast,causal determination,geodesy operation or safe travel/design approval.
Description
Freezing degree-days accumulate the magnitude of daily mean temperatures below freezing.
Freezing degree-days accumulate the magnitude of daily mean temperatures below freezing.1
This tool sums the negative-temperature contribution as a positive index for the supplied daily period rather than calculating ice thickness.
When to use Accumulated Freezing Degree Days Calculator
Use this tool to apply the stated accumulated freezing degree days calculator operation with an explicit input and unit basis.
How to use Accumulated Freezing Degree Days Calculator and how it works
- Establish the measurement basis and units described above.
- Enter actualDailyMeanTemperaturesC and run the tool.
- Read result.value using the output meanings below.
- If input is rejected, correct the stated type, range, ordering or alignment issue and rerun; review successful results under the declared convention.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualDailyMeanTemperaturesC | Daily Mean Temperatures C. Units, ordering and applicable branch are specified in the algorithm. | array of number | required; dense; align related rows as specified; further conditions in the algorithm |
Require a nonempty finite daily-mean Celsius series. Negate each value, replace negative contributions by zero and sum, treating each observation as one day.
freezing degree-days = sum(max(0, −dailyMeanC)) Apply the declared units, ordering and branch conditions.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the declared output fields. | object |
| result.value | Freezing degree-days in °C·days under one-day records. | number |
{
"input": {
"actualDailyMeanTemperaturesC": [
-2,
-1,
0,
1,
2
]
},
"output": {
"result": {
"value": 3
}
}
}Limitations and assumptions
The output applies the declared operation to the values you supply. Establish the measurement basis, units, coefficients and any caller-selected rules before interpreting it. The tool does not independently collect or verify observations or decide whether a model or reference applies.
Supply explicit required fields with the documented types and dense aligned arrays. Unknown fields, wrong types and nonfinite numbers are rejected. Branch-specific constraints are explained above. A returned boolean, signed difference or tied result follows the stated convention; an input error instead means the required input contract was not satisfied. Very large inputs or outputs may be rejected by shared resource limits.
Alternative or Complementary methods
For a related operation, use Thawing Index Accumulator Calculator. A thawing index accumulates warmth above freezing using daily mean temperature.
For a related operation, use Chill Hours Accumulator 0-7.2C. A simple chill-hour model totals time spent in a declared cool-temperature interval.
References
Similar or alternative tools
- Thawing Index Accumulator Calculator
A thawing index accumulates warmth above freezing using daily mean temperature.
- Chill Hours Accumulator 0-7.2C
A simple chill-hour model totals time spent in a declared cool-temperature interval.