NASA

NASA Oceanography & Satellite Radar Altimetry Explorer

Earth Science Division • Orbital Ocean Telemetry Station
Mission Active: SWOT KaRIn
Global Satellite Ocean Track & Surface Anomalies
Orbit Time: T+2026.207
Radar Return Time 8.890ms
SSH Anomaly +1.20cm
Geostrophic Speed 2.40kts
Mapped Coverage 94.5%
Radar Altimeter Waveform Workbench
Significant Wave Height (SWH): 2.5 m
Sea Surface Height Bias (Delta z): +12.0 cm
Satellite Orbital Position Scrub: Lat: 24.5° N
Why NASA Explores Oceans From Orbit

Ships travel at ~15 knots and would take centuries to sample global ocean topography. From 890 km in space, NASA radar altimeters bounce 1,800 Ka-band pulses per second to map global Sea Surface Height with sub-centimeter precision, revealing ocean currents, heat storage, and seamounts.

How Radar Altimetry Works: Microwave pulses emit from the satellite antenna toward the ocean. The round-trip pulse travel time τ = 2h / c measures distance to the surface down to millimeters. The shape (slope) of the returning waveform reveals sea roughness (Significant Wave Height), while the amplitude indicates wind speed.

Geostrophic Current Balance: Water mounds up over warm ocean eddies. Earth's Coriolis force balances these pressure gradients, creating geostrophic currents: u_g = -(g/f) · (∂η/∂y).

NASA Oceanography Explorer | Operational Mode: SWOT KaRIn Radar Synchronized
SSH Precision: 1.2 cm | Speed: 2.4 kts