Live CWA ocean-current data · Updated every 2 days

Forecast ocean drift
across Taiwan waters.

SeaCurrent turns Central Weather Administration open data into actionable drift trajectories — for search & rescue, marine debris, and oil-spill response. Drop a pin, pick a scenario, receive a forecast by email.

Launch simulator Forecast map Tide table GitHub
3Drift models
8Forecast layers
72hHourly horizon
CWA · GFSData sources
seacurrent / forecast · Taiwan waters
Three drift models

Purpose-built for the three most common
open-water response cases.

Each simulation runs OpenDrift in a dedicated Docker environment on GitHub Actions — the same model-family used by national SAR and environmental agencies.

Person overboard

MODEL · Leeway

SAR-grade trajectories for 10 object profiles — PIW, life raft (ballast / canopy variants), fishing vessel, sailboat, surfboard.

  • 10 Leeway object profiles
  • Ballast & canopy variants
  • Search-and-rescue focus

Marine debris

MODEL · OceanDrift

Track floating objects — containers, fishing gear, plastic — with tunable wind drift factors for different buoyancies.

  • Wind drift factor 0 – 0.1
  • Container tracking
  • Debris field forecasts

Oil spill

MODEL · OpenOil

Oil-spill trajectory and weathering. Supports common fuel oil classes with spill-volume parameters.

  • Light / medium / heavy crude
  • Diesel, Bunker C
  • Volume 1 – 10,000 m³
Forecast layers

Eight environmental layers,
one map.

Beyond drift trajectories, the forecast viewer renders animated vector flows for ocean current and wind at multiple altitudes, plus temperature and humidity heatmaps and a tide table for Taiwan harbours.

Ocean current

CWA · M-B0071

Animated surface current vectors, 0 – 1.5 m/s. Drives every drift simulation.

Wind · multi-altitude

GFS · 10 m / 850 / 925 / 1000 hPa

Toggle pressure levels to see boundary-layer vs. surface flow patterns side-by-side.

Temperature

GFS · 2 m / 850 / 925 / 1000 hPa

Per-frame p5/p95 auto-scaling so coastal contrast doesn't get washed out by inland extremes.

Relative humidity

GFS · 2 m / 850 / 925 / 1000 hPa

Heatmap overlay showing moisture distribution from sea surface up through the lower troposphere.

Person overboard

OpenDrift · Leeway

SAR trajectory for PIW, life rafts, fishing & sail vessels — pick from 10 object profiles.

Marine debris

OpenDrift · OceanDrift

Floating-object tracking with tunable wind drift factor (0 – 0.1) for different buoyancy classes.

Oil spill

OpenDrift · OpenOil

Trajectory + weathering for light/medium/heavy crude, diesel, and Bunker C; 1 – 10,000 m³.

Tide table

CWA · F-A0021

High/low water times, tidal range, lunar date and flood/ebb direction for Taiwan harbours.

How it works

From pin-drop to emailed forecast
in four steps.

STEP 01

Drop a pin

Click anywhere in Taiwan waters on the map. Longitude / latitude populate automatically.

STEP 02

Choose scenario

Select Person, Debris, or Oil Spill — then tune object type, wind drift, or oil parameters.

STEP 03

We run OpenDrift

A GitHub Actions job spins up OpenDrift in Docker and runs the model against fresh CWA data.

STEP 04

Forecast in your inbox

A trajectory map (PNG) plus raw JSON lands in your email, typically within minutes.

Data source

Built on authoritative
CWA open data.

Ocean-current fields are pulled from the Central Weather Administration's public NetCDF dataset on AWS S3, converted to CF-convention standard names, and cached as GitHub artifacts. No proprietary feeds. No API keys on the client.

The conversion pipeline renames CWA's UC / VC velocity variables into OpenDrift-compatible x/y_sea_water_velocity, preserving every dimension (time, depth, lat, lon).

SourceCWA OpenData
Bucketcwaopendata.s3…
DatasetModel/M-B0071-*.nc
FormatNetCDF (CF)
VariablesUC, VC → x/y velocity
CoverageTaiwan waters
RefreshEvery 2 days · Actions cron
What you get

A full forecast viewer, not just a simulator.

Animated flow fields

Windy-style particle animation for ocean current and surface wind, with toggleable pressure levels (850 / 925 / 1000 hPa).

Scalar overlays

Temperature and humidity heatmaps at multiple altitudes. Color bars render automatically against 5th / 95th percentile ranges.

72-hour timeline

Scrub or play through three days of forecast frames. Hour snapping handles sparse source data gracefully.

Email delivery

Results ship via SendGrid as a trajectory PNG plus raw JSON. Nothing to install, no account required.

Zero-trust client

No secrets in the browser. The Vercel proxy holds the GitHub token; the client only sees queue IDs.

Fully open source

MIT-licensed. Fork the repo, add GitHub Secrets for SendGrid, and deploy your own instance.

Ready to forecast the drift?

Open the simulator, drop a pin in Taiwan waters, and get trajectories in your inbox.

Launch simulator Forecast map