Alert levels
An alert is a fact about a receptor: at one instant of the forecast, the modelled concentration at that point exceeds a threshold. The demo neither announces nor sends it; it derives it from the forecast and draws it everywhere that receptor appears.
The three levels
Section titled “The three levels”| Level | Colour | Meaning |
|---|---|---|
| Warning | amber | A threshold of attention: worth a look |
| Alert | red | The threshold that calls for action |
| Critical | purple | The highest level the demo distinguishes |
The levels’ identity — name, colour, rank — is the same in every demo; what changes per demo is the value of each threshold, per species. Quintero’s thresholds are its own and are read in the dashboard’s Domain section. A receptor with nothing to report shows green: not a level, the absence of all of them.
How it is evaluated
Section titled “How it is evaluated”- Against the total. An alert is computed on the sum of all sources, in each scenario separately. A source group alone does not cross thresholds; the sum does.
- With the receptor’s native value — what the model computed at that point, not the layer’s colour around it.
- Per species and per scenario. Changing scenario changes the alerts; changing species changes which are seen.
- An instant counts. The demo’s threshold is instantaneous: it is compared step by step. A crossing that lasts a single step still shows, widened to that step, so it does not vanish from the bar.
Beyond the instantaneous thresholds, the platform evaluates the air-quality standards with their own averaging — hourly, 8-hour moving — and computes each species’ margin against its standard. That computation exists in the published data; its presentation on screen does not yet.
Where it shows
Section titled “Where it shows”- On the receptor’s marker: the symbol’s colour, at the instant shown.
- On the timebar: hours with any receptor over a level, tinted with the worst level.
- In the Alerts panel: every period ahead, with its worst level, its peak and its threshold.
- In the Receptors panel: the Total column coloured by level.
- On the dashboard: Home — active now, next, worst ahead —, Forecast → Outlook and Receptors → Standings.
What has passed and what is coming are told apart by their position against the forecast cycle: an alert in the shaded past is recent history; one to the right of the now is what the forecast announces.