Reading a receptor

A receptor is a point where concentration matters: in Santiago, each one has its reason for being where it is — this demo’s page tells it. Everything the demo says about a receptor comes from the same modelled series; what changes is the question.

Finding it

Three doors, and each one selects the receptor for every panel at once: click its marker; pick it in the top bar’s LOCATION search box; or click its row in the Receptors panel or in Alerts. A pick from a list flies the camera to it; a click on the marker does not move the camera, since the receptor is already under the cursor.

The card: Loc. Info

Loc. Info opens the Information panel — the receptor’s card, its kind and name over three tabs: Information — the code, the elevation, the sampling height, the coordinate in three forms (latitude and longitude, model grid and UTM) —; Data, the series published at this point; and Reference, what the inventory notes about the place. Where the receptor is also a monitoring station, the same card carries the station’s measured readings.

The curve: the Series panel

Series draws the concentration at the receptor across the whole forecast, for the species, scenario and group the top bar states, with the demo’s thresholds as dashed lines. It answers the perennial question: has the peak passed, or is it still to come? A click on the curve moves the whole view to that instant — map included.

Its builder adds more curves to the same chart: another receptor, the measured series at a station beside the modelled one, a 1-hour or 8-hour moving mean instead of the instant value, another scenario or one source group. When the top bar has a source group selected, the main curve still shows the Total, and says so: a group’s contribution is not comparable with a threshold, and the series exists to be compared with thresholds.

The table: the Receptors panel

Receptors lists every receptor in the domain with its value at the current instant, sortable by value or narrowed to Alerts only, and a Pivot control to read the table three ways: by Group — how much each source group contributes, with the Total column coloured by level —, by Species or by Scenario.

The alerts ahead: the Alerts panel

Alerts is a vertical timeline, forward only, with one tab per species. Each row is a period in which a receptor exceeds some level: the worst level reached, the span, the peak reached in this period and that level’s threshold; a row from the regulatory standard is tagged so. A click on the row sets the receptor, the species and the instant of the worst moment. If it says No alerts forecast ahead in this scenario, that is exactly what it means.

Against the standard: the Regulatory panel

Hidden for now: the map’s rail carries no button for this panel.

Regulatory reads the receptor against Santiago’s standard for the current species: the instantaneous value, the current hour’s mean, the norm, and the margin as a percentage of it. With the Controls’ step set to one hour, the forecast is walked the way the standard is written.

Where the value comes from

A receptor’s value is what the model computed at that point, not the layer’s colour interpolated around it: the layer is drawn on a grid, the receptor is sampled separately and in more detail. That is why, right next to a source, the marker can say something different from what the layer suggests — and the marker is right.

→ Comparing a scenario · Panels · Alert levels