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Full catalog/PRIM_SMAP_L2_V1
PRIM_SMAP_L2_V1·v1.0·dataset

How rain disturbs salinity readings (SMAP model)

Parametrized Rain Impact Model for SMAP L2 V1.0
ocean NASA POCLOUD Level 2 netCDF4
In plain English

What it measures. Estimates of ocean salt content (salinity) at the surface and at 1 and 5 meters depth, plus the chance that rain has layered the water, along with rainfall rate and wind speed.

How it's made. Produced by applying a Parameterized Rain Impact Model to data from NASA's SMAP satellite, accounting for how rain disturbs salinity readings; each file covers one roughly 98-minute orbit.

How & where you'd use it. Helps researchers correct and interpret ocean salinity measurements affected by rain, improving studies of the ocean's freshwater and salt balance.

What's measured

OCEANS › SALINITY/DENSITY › SALINITYOCEANS › OCEAN WINDS › SURFACE WINDS › WIND SPEEDOCEANS › PRECIPITATION › LIQUID PRECIPITATION › RAIN

Coverage & cadence

  • Time span2015-03-31 → 2021-10-01
  • Measured bySMAP (SMAP L-BAND RADIOMETER)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • FormatsnetCDF4
  • StatusACTIVE

What you can do with it

  • Watch sea-surface temperature and marine heatwaves
  • Spot algal blooms and ocean-colour shifts
  • Support fisheries and coastal monitoring
Official description

This is the PI-produced SMAP sea water salinity, level 2 v1.0 orbital/swath product from the NASA Soil Moisture Active Passive (SMAP) observatory. It is based on the Parameterized Rain Impact Model (PRIM) developed at the University of Central Florida (UCF) Central Florida Remote Sensing Lab (CFRSL), Orlando, FL; University of Washington (UW) Applied Physics Lab (APL), Seattle, WA. The PRIM product range extended from March 31, 2015 to September 30, 2021. It includes data for a range of parameters: derived SMAP sea water salinity at surface, 1m depth and 5m depth, and probability of salinity stratification (PSS), rainfall rate and wind speed data. Each data file covers one 98-minute orbit (15 files per day), and corresponds to a <a href="https://doi.org/10.5067/SMP50-2TOCS">JPL SMAP Level 2B CAP Sea Surface Salinity V5.0</a> file which corresponds to a single orbit on a given day. The SMAP satellite is in a near-polar orbit at an inclination of 98 degrees and an altitude of 685 km. It has an ascending node time of 6 pm and is sun-synchronous. With its 1000km swath, SMAP achieves global coverage in approximately 3 days, but has an exact orbit repeat cycle of 8 days. On board Instruments include a highly sensitive L-band radiometer operating at 1.41GHz and an L-band 1.26GHz radar sensor providing complementary active and passive sensing capabilities. Observations are global in extent and provided at 25km swath grid with an approximate spatial resolution of 60 km.

Get the data

prim_smap_l2_v1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PRIM_SMAP_L2_V1",
    version="1.0",
    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.