Global Forest Watch, canopy loss during 2020-2023

Source: Global Forest Watch (Hansen/UMD/Google/USGS/NASA) Year: 2020-2023 Category: Transition risks · Ecosystem use Coverage: Global Format: Raster grid (~1 km) Used in risk analysis: Yes — gates Ecosystem use

What it shows

This layer maps where tree canopy was lost between 2020 and 2023. It captures the disappearance of trees taller than five metres in areas that had dense canopy cover, regardless of whether the cause was human or natural, and whether the loss is permanent or temporary. It matters because canopy loss is a leading signal of land-use change, habitat conversion and deforestation pressure.

How it is built

The underlying data is the University of Maryland (UMD) tree-cover-loss dataset, accessed through Global Forest Watch. It records annual loss of all trees taller than five metres between 2020 and 2023, in areas that had more than 50% canopy cover in the year 2000. The loss includes natural forests as well as plantations and tree crops. Each cell of the roughly 1 km grid records the fraction of its area (from 0 to 1) that experienced canopy loss over the period.

How to read it

Higher values mean a larger share of the grid cell lost canopy during 2020–2023; a value near zero means little or no detected loss. Concentrations of high values indicate areas under active deforestation or land-clearing pressure.

Class thresholds

The underlying layer models a physical quantity: the fraction of a grid cell's area (0–1, i.e. 0–100%) that lost tree canopy between 2020 and 2023 — the share of each roughly 1 km² cell where trees taller than five metres disappeared from zones that had more than 50% canopy cover in 2000. It is a continuous fraction rather than a set of discrete physical classes, and the layer is rendered as a linear colour ramp over the displayed range:

Values between these endpoints are shaded continuously, so darker cells lost a greater share of their canopy.

A site is flagged on the Ecosystem use dimension when the layer value exceeds 0.3 (a 30% canopy-loss fraction) — the proximity trigger of "Proximity with significant canopy loss area (>30% loss fraction, GFW 2020-23)". On its own this yields Potentially material; combined with a material "Area of land use" ENCORE pressure it becomes Very material.

How these thresholds were set. This is a Darwin in-house classification: the quantity itself (canopy-loss fraction) comes straight from the Hansen / UMD / Global Forest Watch tree-cover-loss dataset, but the 0.0–0.5 display range and the 0.3 risk-flag cut-off are fixed round-number choices made in Darwin's configuration, not derived from WWF or any other published standard.

Source

Hansen / UMD / Google / USGS / NASA, accessed through Global Forest Watch. Hansen, M. C., et al. (2013), "High-Resolution Global Maps of 21st-Century Forest Cover Change," Science 342: 850–53. Data version GFC-2024-v1.12. Licensed CC BY 4.0.

Comparison with the WWF Risk Filter Suite

This layer maps to WWF Biodiversity Risk Filter indicator S13_2 Forest Canopy Loss, and also contributes to S13_1 Land-Use Change. WWF draws on the same Hansen / Global Forest Watch tree-cover-loss family; the main difference is that Darwin's layer is restricted to the recent 2020–2023 window rather than the full historical record.

Risk analysis

A site is flagged on a dimension by combining a proximity trigger (this layer) with an activity trigger (the entity's ENCORE pressure/service). Proximity only → Potentially material; proximity and the matching ENCORE pressure/service is material → Very material; neither → Not material.

Legend

Symbolised field: Canopy loss fraction (2020-2023)

Generated from darwin/layers/layer-global-forest-watch-canopy-loss-during-2020-2023.toml and risk_indicator_pairs.toml (develop).