Working with Layers
The Criora map can overlay any of 17 environmental data layers on top of the base map. This guide explains how to find, toggle, and read those layers.
Where to find the layer panel
Open any map view (the landing map or a saved location) and click the Layers button in the top-right of the map. The panel slides in with all available data sources, grouped by theme.
Layer groups
Layers are organised into nine themes:
| Group | What’s in it |
|---|---|
| Temperature | ERA5 monthly and extreme temperatures, Köppen climate zones |
| Precipitation | ERA5 rainfall, drought-risk reduction (Aqueduct DRR) |
| Wind | ERA5 wind speed and gust extremes |
| Water | Aqueduct baseline water stress, JRC global surface water, lakes/wetlands (GLWD) |
| Flooding | Riverine flood risk, coastal flood, near-real-time flood forecast |
| Vegetation | NDVI vegetation index |
| Terrain | Digital elevation, distance to coast |
| Land cover | MODIS land cover classes, GHSL built-up surface |
| Misc | Drought index (SPI-12), sea-level-rise projections, land subsidence |
Click a group header to expand it. Each entry inside is one layer: a dataset that can be toggled on the map.
Toggling a layer
Click a layer name to switch it on. The map renders the layer as a semi-transparent overlay (50% opacity by default) on top of the base map. Click again to hide it.
You can have multiple layers on at once, they stack in the order you enabled them. The panel shows a check next to every active layer so you can see what’s currently visible.
Variants
Some layers have multiple variants: different views of the same dataset. For example:
- Aqueduct Water Stress has two variants: baseline water stress (
bws) and drought-risk reduction (drr). - DEM has three variants for different elevation derivatives.
- ERA5 Monthly has 19 variants (one per climate variable: 2m temperature, dewpoint, wind components, precipitation, soil moisture layers, and more).
When a layer has variants, a small selector appears next to its name. Pick one to switch the variant, the legend and tile colours update immediately.
Year slider (temporal layers)
Layers backed by time-series data show a year slider at the bottom of the map when active. Drag the slider to jump between years. Examples:
- ERA5 monthly climate (covers ~1950 to recent)
- ERA5 extremes (recent decades)
- NDVI (annual composites)
- SLR projections (multiple target years)
If you have multiple temporal layers active at once, the slider applies the chosen year to whichever layer supports it.
Reading the legend
Every active layer adds a legend strip on the right side of the map. There are two types:
- Categorical: a list of named classes with discrete colours (e.g. Aqueduct Water Stress: Low → Extremely High).
- Gradient: a continuous colour ramp from min to max with units (e.g. ERA5 temperature in °C, NDVI from 0 to 1).
Higher-risk values typically map to warmer colours (yellow → orange → red) but always read the legend, some layers (like NDVI) reverse this convention because higher vegetation is generally better.
Click to inspect
With one or more layers active, click anywhere on the map. A popup shows the value of every visible layer at that exact coordinate, along with the layer name and unit. This is the fastest way to compare two locations on the same metric, open the layer, click point A, click point B.
When inspecting a categorical layer (e.g. Köppen), the popup shows the class name (e.g. “Cfa - Humid subtropical”) rather than a raw number.
Sources and licensing
Each layer carries source attribution shown in the layer panel and on the map’s bottom-right corner when active. Full provider, resolution, and licensing details are listed in Data Sources. All layers Criora ships are open or free-to-use under the providers’ terms.
What layers feed the report
Map layers and risk scores share the same underlying data. When you generate a location report, the platform queries the same datasets shown in the layer panel, so anything you can visualise on the map is also feeding the score on your report.
The relationship is one-way for the user: turning a map layer on or off does not change a saved report’s score. To re-score a location, regenerate the report from its detail page.
Layers vs dispatches
Layers are pre-aggregated, gridded datasets visualised as overlays on the map: climatology, water stress, sea-level-rise projections, and similar. They tell you what the long-term picture looks like.
For live, point-level events (active wildfires, earthquakes, flood alerts) around a specific location, see the dispatch radar on the Outlook tab of a report. The dispatch radar is documented separately in Live Dispatches.
Related
- How Scoring Works: what those layer values become in a report
- Reading a Report: turn a location into structured ESG output
- Live Dispatches: near-real-time point events on the Outlook tab
- Data Sources: provider, resolution, and license per layer