Sea ice on the map

The Sea ice layer is a maritime-map layer on rynda.io that shades waters by sea-ice concentration. It shows where the water is open, where the ice is sparse or close, and where fast ice sits along the coast — based on official ice charts from national ice services.

Sea-ice layer on the rynda.io map: concentration shading and the class legend

What the layer shows

The fill colour corresponds to an ice class — from open water to consolidated ice:

Class	Meaning
Ice-free, open water	no ice or less than 1/10
New and thin ice	ice up to 15 cm thick
Open ice (1–6/10)	navigable, depending on the vessel's ice class
Close ice (7–10/10)	movement without icebreaker support is limited
Fast ice	immobile ice attached to the shore

The exact colour legend opens with the layer on the right side of the map. Each chart's source and date are shown in the legend and in the popup — click the ice to see the class, source and date for a specific spot.

How to turn it on

Open the Maritime Map.
In the left rail, pick the "Ice and polar waters" group.
Switch on "Sea ice".
For Arctic routes, also switch on "NSR zones" next to it — admission regimes overlay the ice picture.

Ice report (PDF)

The layer legend has a report download button — it packs the ice picture into a document you can attach to voyage planning or forward to colleagues.

Without an account and on FREE, the button reads "Download a sample report (PDF)": a sample downloads, showing the document's structure and quality. The line under the button leads to the PRO plan.
On PRO and ENTERPRISE, the button reads "Ice chart report (PDF)" and generates a full report for the conditions at request time.

Limits

Ice services update their charts on their own schedule — each chart's date is visible in the legend; the ice edge can shift between updates.
The layer is for situational awareness, not for navigation: decisions about moving in ice are made from official ice bulletins, icebreaker-pilotage guidance and the vessel's ice-class documents.

Ice + NSR zones + weather on one map — the picture for an Arctic passage comes together without switching between services.