PM2.5 Natural Floor

Source: IPCC CMIP6 (GFDL-ESM4, GISS-E2-1-G, MIROC-ES2L) Year: 1901-1910 Category: Scenario Format: Raster grid (COG) Used in risk analysis: Context only. It is the floor that PM2.5 Degradation is measured from; Resilience does not read this layer as a level.

What it shows

This layer shows the surface concentration of fine particles (PM2.5) in 1901-1910, in µg/m³. It stands for the natural background of the Atmosphere asset: the floor from which PM2.5 Degradation counts today's excess.

How it is built

The floor is the 1901-1910 surface PM2.5 over the three CMIP6 models of the PM2.5 shock: GFDL-ESM4, GISS-E2-1-G and MIROC-ES2L. The models publish PM2.5 as a mass ratio (kg/kg). It is converted to µg/m³ with one surface air density, 1.2 kg/m³.

The decade is 1901-1910 rather than 1850 because GISS-E2-1-G publishes no earlier PM2.5.

The layer is a state, and it is deliberately not tagged as a shock layer. Tagging it would make it compete with the PM2.5 shock layers for the Atmosphere asset.

How to read it

A darker cell had more fine particles in 1901-1910. Two caveats matter:

• The floor sits slightly high. The other two models rise by 3-6 % between the 1850 decade and 1901-1910, so the floor is a little above what an 1850 floor would read.
• Some floors are high. Dust and sea salt put the floor above 35 µg/m³ on 1.7 % of cells.

Source

CMIP6: GFDL-ESM4, GISS-E2-1-G, MIROC-ES2L.

Related pages: PM2.5 Degradation, PM2.5 shock (SSP1-2.6), PM2.5 shock (SSP3-7.0), Shock layers.

Legend

Symbolised field: PM2.5 (µg/m³)

Generated from darwin/layers/layer-pm25-floor-1901.toml (develop).