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Full catalog/SWOT_L2_HR_PIXC_D
SWOT_L2_HR_PIXC_D·vD·dataset

Detailed point-by-point map of surface water (SWOT)

SWOT Level 2 Water Mask Pixel Cloud Data Product, Version D
hydrosphere NASA POCLOUD Level 2 netCDF-4
In plain English

What it measures. A point-by-point map of where there's water on land - rivers, lakes, floodplains, and wetlands - showing each spot's exact location and elevation. It also records how strongly the radar signal bounced back and tags each point as land, water, ice, or another surface type.

How it's made. Built from the KaRIn radar instrument on the SWOT satellite, this is the foundational raw 'pixel cloud' data captured at the instrument's full resolution, before features like rivers and lakes are pulled out in later products.

How & where you'd use it. It supports detailed water mapping, flood tracking, and spotting changes over time, but as a raw building-block product most people use it indirectly through the higher-level river and lake products derived from it.

What's measured

TERRESTRIAL HYDROSPHERE › SURFACE WATER › SURFACE WATER FEATURES › RIVERS/STREAMSTERRESTRIAL 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
  • FormatsnetCDF-4
  • 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 Water Mask Pixel Cloud Product (SWOT_L2_HR_PIXC_D) provides high-resolution, geolocated observations of terrestrial surface water pixels detected by the Ka-band Radar Interferometer (KaRIn) onboard the Surface Water and Ocean Topography (SWOT) satellite. This product contains the foundational “pixel cloud” data from which hydrologic features such as rivers, lakes, floodplains, and wetlands are later identified and analyzed in higher-level products. The PIXC product provides the unstructured point cloud of water detections at full instrument resolution (~15–25 m cross-track, ~5–10 m along-track), supporting fine-scale hydrologic analyses and applications such as water body delineation, flood mapping, and change detection. Each granule represents one KaRIn high-rate tile (~64 × 64 km²), corresponding to either the left or right half of the instrument swath. It includes individual water pixel detections with associated geodetic coordinates, ellipsoidal heights, normalized radar backscatter, and classification flags indicating surface type (e.g., land, water, ice, or layover). Pixel heights are referenced to the WGS84 ellipsoid and are not corrected for solid Earth tides, ocean tides, or pole tides like KaRIn low-rate oceanography products. Users may apply additional processing or corrections depending on the intended scientific use. Data are distributed in NetCDF-4 format and follow Climate and Forecast (CF) metadata conventions. The PIXC product is complemented by an auxiliary pixel cloud product (PIXCVec) that provides a less noisy, height-constrained geolocation of the observed water pixels and identifies associated river and lake features in the SWOT Prior River & Lake Databases (PRD & PLD). Together they support the derivation of higher-level, featured based River and Lake hydrology products from SWOT.

Get the data

swot_l2_hr_pixc_d_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SWOT_L2_HR_PIXC_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.