Transfer diagnostics

EPAC Transfer Diagnostics

PTEM has been independently ported into the Eastern Pacific (EPAC) under the same governed execution contract as Atlantic: forward-only computation, immutable freezes, manifests, and receipts. Portability is treated as a measurable property of the instrument, not a marketing claim.

Each basin computes regime thresholds natively using the same pre-declared percentile rule. Threshold magnitudes differ by basin because structural amplitude differs; portability is evaluated through controlled transfer tests rather than threshold equality.

PTEM publishes transfer scorecards derived from frozen structural spines:

• • Cross-threshold stress tests (Atlantic threshold applied to EPAC; EPAC threshold applied to Atlantic)
• • Diagonal transfer (early-era calibration evaluated on late-era data, applied across basins)
• • Ratios referenced to basin-appropriate native baselines (late-native baselines for diagonal transfer)

Interpretation boundary:
Transfer diagnostics are comparative readouts only. They do not assert basin equivalence, replace basin-specific climatology, imply forecasting equivalence, or modify canonical structural truth.

This converts portability from a qualitative claim into a measurable property of the instrument.