Koppen Subclass Letter Resolver
Parse valid Köppen subclass letters by group syntax, does not derive climate from missing monthly data. Caller independently establishes homogeneous observation coverage and model/reference applicability; not observed future climate, crop suitability or validated drought severity.
Description
A Köppen code contains group and subclass symbols with group-specific meanings.
A Köppen code contains group and subclass symbols with group-specific meanings.1
Decomposing a supported code differs from classifying raw monthly climate observations. Use Koppen Subclass Letter Resolver to evaluate the supplied inputs under the model explained below.
When to use Koppen Subclass Letter Resolver
Use Koppen Subclass Letter Resolver to evaluate the supplied inputs under the model explained below. Establish the units, measurement scope and model assumptions before entering values.
How to use Koppen Subclass Letter Resolver and understand its results
- Establish the units, measurement scope and model assumptions before entering values.
- Enter Observed koppen code using the field table and validation rules below, then run the tool.
- Read Main climate group, Precipitation subclass, Thermal subclass; interpret the units, signs, ordering and unknown-value placeholders described below.
- Correct reported input errors and rerun. Apply successful results according to their specific meanings and check the assumptions before using them in a decision.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedKoppenCode | Observed koppen code | string | Required; constraints below |
Enter a complete case-sensitive code matching A followed by f/m/w/s; B followed by W/S and h/k; C or D followed by s/f/w and a/b/c; D followed by s/f/w and d; or E followed by T/F. Return the first symbol as main group, the second as precipitation subclass except E returns an empty placeholder, and the third as thermal subclass except E uses its second symbol and A returns empty. This is code syntax decomposition without observations or climate verification.
main=s[0]; precipitation=(main==E ? empty : s[1]); thermal=(length==3 ? s[2] : main==E ? s[1] : empty) Use the field order, units and branch conditions described above.
| Output field | Meaning | Value type |
|---|---|---|
| mainClimateGroup | Main climate group | string |
| precipitationSubclass | Precipitation subclass | string |
| thermalSubclass | Thermal subclass | string |
{
"input": {
"observedKoppenCode": "Dfb"
},
"output": {
"mainClimateGroup": "D",
"precipitationSubclass": "f",
"thermalSubclass": "b"
}
}Limitations and assumptions
Decomposing a supported code differs from classifying raw monthly climate observations. Apply the exact scope and assumptions explained above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse arrays fail validation. Domain-specific bounds, alignments and supported tokens are explained above; extremely large inputs or outputs can also be rejected. Input errors differ from successful false results, empty match lists and unknown-evidence placeholders.
Alternative or Complementary methods
Use Koppen Climate Class Classifier for a related task: A Köppen-style classifier uses monthly temperature and precipitation normals and a hemisphere convention.
Use Trewartha Climate Classifier for a related task: Trewartha-style groups combine temperature seasonality with an aridity criterion.
References
-
Koppen Subclass Letter Resolver — tool.io
Similar or alternative tools
- Koppen Climate Class Classifier
A Köppen-style classifier uses monthly temperature and precipitation normals and a hemisphere convention.
- Trewartha Climate Classifier
Trewartha-style groups combine temperature seasonality with an aridity criterion.