Coastal & marine
Depths, tides and shorelines: bathymetry grids, which line is the coast, inundation, vessel tracks and the sea areas a country can claim.
The coast is the one boundary that does not hold still. Mean high water springs, mean sea level and mean low water springs are all defensible definitions of "the shoreline", and on a shallow beach they can be hundreds of metres apart. A coastline dataset is a tidal datum somebody chose, and the file name almost never says which.
Depths have the same problem from the other direction: bathymetry is measured down from a chart datum, elevation up from a vertical datum, and joining the two across the shoreline without reconciling them produces a surface with a step in it. Add vessel tracks, which are AIS with gaps, and maritime boundaries, which are legal constructions with rules about which baseline they are measured from.
The concepts settle what each datum means and which line is which; the how-to guides work with bathymetry grids, inundation and vessel data; and the fixes cover the joins and shorelines that come out wrong.
🧭 Start with the concepts
The ideas the how-to guides below assume you already have.
⚙️ Then do the task
Step-by-step walkthroughs with code you can copy and adapt.
- How to load and plot a bathymetry grid in Python
- How to extract a coastline from a raster in Python
- How to measure shoreline change between two dates
- How to fetch and align tide gauge data in Python
- How to map coastal inundation from a DEM in Python
- How to compute distance to the coast for many points
Show every how-to guide in this topic
- How to clip a dataset to an exclusive economic zone
- How to clean AIS vessel tracks in Python
- How to generate depth contours from bathymetry
- How to subset an ocean model NetCDF by depth and time
- How to Compare Buoy Water Temperature with Satellite SST in Python
- How to Extract a Sea Surface Temperature Time Series at a Point in Python
🔧 When it breaks
The errors this topic produces, with the cause explained rather than just the command.
Learning paths through this topic
A curated route rather than a list — the guides in the order that builds on itself.
Related topics
Subjects that keep coming up alongside this one, most overlap first.