Cryic conditions (WRB 2022)

Tests whether continuous frozen / permafrost material occurs within the upper max_top_cm. Two alternative paths qualify per WRB 2022:

1. Permafrost temperature: a layer at top_cm <= max_top_cm (default 100) with permafrost_temp_C <= max_temp_C (default 0 C).

2. Designation pattern: a layer at top_cm <= max_top_cm with designation containing suffix "f" (frozen) or matching "^Cf" / "perma". Used as a fallback when the temperature field is not in the pedon (typical of legacy survey data).

Either path qualifies. Diagnostic of Cryosols.

Usage

cryic_conditions(pedon, max_top_cm = 100, max_temp_C = 0)

Arguments

pedon

A PedonRecord.

max_top_cm

Maximum top depth (cm) (default 100).

max_temp_C

Maximum mean annual permafrost-zone temperature (deg C) for the temperature path (default 0).

Value

A DiagnosticResult.

References

IUSS Working Group WRB (2022), Chapter 5, Cryosols.