How to use this site

Practical answers for the inventory map, most-asked first. This page is about driving the site; the science behind the data — classification, rules, areas and volumes — lives in Methods.

What do the dots and colors mean?

Catastrophic landslides are blues, darkest for the most recent (2012+), lighter for Modern (1850–2011), lightest for Holocene. A colored ring around a catastrophic dot records precursory creep evidence.
Slow-moving landslides are red / yellow / green by strength of movement evidence: red = obvious creep, yellow = subtle (e.g. InSAR-detected), green = geomorphic evidence only. A yellow dot with a red center = patchy obvious creep.
Magenta = a record still missing the key attribute its display depends on (under review).
Half-size dots are features below the inventory's size thresholds; they carry the same colors.
The full clickable legend, with per-class counts, is the Inventory tab of the sidebar. Zoom in and the dots gain their mapped outlines (source, body, deposit polygons).

How do I look at a specific landslide?

Click any dot or polygon: the panel shows its attributes, evidence, imagery links, and — for many recent events — an embedded Planet satellite timelapse.
Field photos, where available, appear as a thumbnail strip in the panel — click one for a fullscreen slideshow (arrow keys or swipe to browse; featured photos lead, the rest run oldest-first). While the panel is open, small white dots on the map mark where geotagged photos were taken — click a dot to open that photo. A numbered dot is several photos from one spot. Camera positions can sit well away from the landslide (aerial obliques especially).
Double-click a landslide to jump to its curated best view (framing, imagery, sometimes a before/after wiper). The ⌖ Default view button in the panel does the same.
The record's name is a permalink — right-click it and copy to share a URL that opens the map right there.

How do I change the imagery, or compare two eras?

Switch basemaps with the dropdown at the top of the sidebar, or browse thumbnails in the Reference maps tab — including 1978–86 AHAP aerial photography and historic topo.
For side-by-side comparison, click ＋ Add wiper (Compare section of Reference maps). A draggable ⇄ divider splits the map, and a panel appears on the right: the sidebar controls the left side, the panel controls the right — pick each side's basemap and overlays independently. E.g. AHAP left vs modern satellite right to see decades of change. Landslide data reads continuously across the divider; untick classes for a clean image-only wipe.
Overlays: drape USGS landslide susceptibility, OPERA InSAR velocity (ascending / descending), or ITS_LIVE glacier flow (speed, seasonal amplitude, and speed trend), or glacier thinning (Hugonnet et al. 2000–2019 dh/dt) semi-transparently over the basemap, with an opacity slider — in the sidebar for the map (left side while wiping), in the wiper's panel for the right side. E.g. the same imagery on both sides with ascending velocity on one and descending on the other, to check whether a slope's motion is real or a look-direction artifact; or glacier speed against its trend to spot accelerating ice near a landslide. A "None (blank white)" basemap is available when you want an overlay on a clean canvas.
Each landslide's panel also links out to external imagery browsers (ESRI Wayback time series, Sentinel, OPERA InSAR, historic topo).

Copy the address bar — the URL always encodes your center, zoom, basemap, and any active wiper (with its divider position). For a single landslide, prefer its name-permalink; that link survives map changes and opens at the record's curated view.

How do I filter what's shown?

Type and class checkboxes: pinned strip + Inventory tab; counts update live.
Dual-handle sliders (Inventory tab) filter by source/deposit area, volume, age, and modeled susceptibility.
Limit to map view restricts the counts and the analysis charts to the current screen.

How do I explore timing and statistics?

The Analysis tab opens floating panels: the seasonal histogram, the time series, and the susceptibility scatter — on the scatter, drag a box to filter the map to that range (two-way synced with the sliders). OPERA velocity — asc × desc plots a 2-D histogram of InSAR velocity for every on-screen pixel covered by both tracks, updating as you pan. Density stretched along the y = −x diagonal means opposite signs in the two look directions — east/west aspect-driven motion — while y = x means same-sign (vertical-ish) motion; a tight blob at the origin is stable terrain.

How do I get the data?

⬇ Download in the header: the full inventory as GeoJSON with QGIS styles and a manifest (formats, conventions, rules, attribution). Drag into QGIS and the styling auto-applies. See Methods §1 for the format.

Small conveniences

Right-click (Ctrl-click on Mac) anywhere on the map copies the coordinates to your clipboard.
Panel sections (time-lapse, photos, imagery links, evidence, notes) minimize with the − in their header — each stays minimized as you click through landslides, until you expand it again.
Leaving the map to another page and returning restores the view you left.