Stress-week Count

Stress-week count is the annual tally of weeks during which a piece of land was under environmental stress: high vapour pressure deficit, drought stress, heat stress, or other zone-specific stressors.

It is derived from daily climate data from ERA5-Land (the European Centre for Medium-Range Weather Forecasts’ high-resolution land-surface reanalysis), aggregated to weekly bins and compared against zone-specific stress thresholds. A week is “stressed” when its key climate variables sit outside the optimal range for the local ecoregion.

What it’s used for. EcoIntel uses the stress-week count to de-trend ecological scores for the weather of the year. A year with 20 stressed weeks gets contextualised differently from a year with 8. This enables fair year-on-year comparison: when scores fall, was that the land doing worse, or the year being harder?

As a leading climate-risk signal. Properties whose stress-week count is rising are heading into more challenging operating conditions regardless of management. The trajectory of stress-week count is part of every property’s annual report, and is a leading indicator for climate-adaptation planning: water storage, drought-tolerant species, shade infrastructure, calendar shifts.

The stress-week count is also the basis of the Annual Weather Class label (Normal / Stressed / Severely-stressed) that caveats each year’s scores.