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Full catalog/SWOT_L2_HR_LakeSP_D
SWOT_L2_HR_LakeSP_D·vD·dataset

Lake water levels and extent from space (SWOT)

SWOT Level 2 Lake Single-Pass Vector Data Product, Version D
hydrosphere NASA POCLOUD Level 2 Shapefile
In plain English

What it measures. Where lakes and other water bodies are, how big their surface is, and how high their water sits, along with quality flags and estimates of how their stored water is changing.

How it's made. Produced from the KaRIn radar instrument on the SWOT satellite, which turns its high-resolution measurements into map-ready outlines (shapefiles) of each lake along a single satellite pass.

How & where you'd use it. Lets researchers and water managers monitor lake levels and storage changes worldwide, useful for tracking droughts, floods, and freshwater supply.

What's measured

TERRESTRIAL HYDROSPHERE › SURFACE WATER › SURFACE WATER PROCESSES/MEASUREMENTSTERRESTRIAL HYDROSPHERE › SURFACE WATER › SURFACE WATER FEATURES › LAKES/RESERVOIRS

Coverage & cadence

  • Time span2022-12-16 → ongoing
  • Measured bySWOT (KaRIn, Jason-class Altimeter, AMR, DORIS, GPSP, LRA)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • FormatsShapefile
  • StatusACTIVE

What you can do with it

  • Follow rainfall, floods and surface-water extent
  • Track soil moisture and the onset of drought
  • Monitor lakes, rivers and groundwater storage
Official description

The SWOT Level 2 Lake Single-Pass Vector Product (SWOT_L2_HR_LakeSP_D) provides geolocated surface water measurements for lakes and unclassified water bodies, derived from high-resolution radar observations collected by the Ka-band Radar Interferometer (KaRIn) on the SWOT satellite. This product reports water surface elevation, surface area, and quality indicators for each observed lake or feature, with polygons generated from the PIXCVec pixel cloud. It includes features linked to the Prior Lake Database (PLD), as well as unassigned features not recognized as lakes or rivers in the PLD or PRD. Each granule covers a full KaRIn swath for a single continental pass and contains three ESRI shapefiles: one observation-oriented file of observed PLD lakes, one PLD-oriented file with prior lake features (including unobserved ones), and one file for unassigned features. Observed quantities are referenced to the WGS84 ellipsoid and corrected for geoid height, solid Earth, load, and pole tides, as well as tropospheric and ionospheric path delays. Attributes also include uncertainties, flags for partial or dark water coverage, ice cover, and crossover calibration. Storage change estimates are reported in the PLD-oriented shapefile using both direct and incremental methods under different bathymetric assumptions. The LakeSP product provides consistent reach-scale and basin-level lake measurements suitable for time series analyses, hydrologic modeling, and integration with prior lake databases. It enables monitoring of water level changes and surface area dynamics across a wide range of inland water bodies and supports hydrological applications in water balance studies, reservoir management, and climate impact assessment. This dataset is the parent collection to the following sub-collections: https://podaac.jpl.nasa.gov/dataset/SWOT_L2_HR_LakeSP_obs_D https://podaac.jpl.nasa.gov/dataset/SWOT_L2_HR_LakeSP_prior_D https://podaac.jpl.nasa.gov/dataset/SWOT_L2_HR_LakeSP_unassigned_D

Get the data

swot_l2_hr_lakesp_d_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SWOT_L2_HR_LakeSP_D",
    version="D",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from POCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.