Ocean haze and water properties from polarized light (PACE)
What it measures. Properties of haze over the ocean and of the water itself, worked out from polarized light: how thick the haze is, what the particles are like in size and composition, plus ocean surface roughness and a chlorophyll estimate that hints at phytoplankton.
How it's made. Retrieved from the SPEXone polarized-light instrument on NASA's PACE satellite using an algorithm that solves the atmosphere and ocean together, then mapped globally.
How & where you'd use it. Used for studying airborne particles and climate, correcting ocean-color measurements, and evaluating models; often paired with other PACE instruments for cross-checks.
What's measured
Coverage & cadence
- Time span2024-02-05 → ongoing
- Measured byPACE (SPEXone)
- Processing levelLevel 3
- Spatial extent-180, -90, 180, 90
- FormatsnetCDF-4
- 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 suite provides aerosol optical/microphysical properties retrieved over the oceans, along with coupled surface parameters used in the retrieval. The suite includes spectral aerosol optical depth (AOD), single-scattering albedo (SSA), complex refractive index (real/imaginary), size distribution metrics (e.g., fine/coarse effective radii and fine-mode fraction), and aerosol shape/fraction spherical; it also reports ocean surface roughness (glint/wind parameterization) and “ocean body” properties that define the water-leaving signal for consistency with the coupled atmosphere–ocean inversion. Use AER_RTAPOCEAN for aerosol-climate and air-quality studies, as aerosol context for ocean-color atmospheric correction, and for model evaluation and data assimilation; pair it with OCI/HARP2 products for cross-sensor analyses. Core geophysical variables in this suite include: The RemoTAP Level-3 Chlorophyll-a (Chla) product provides estimates of surface chlorophyll-a concentration, a commonly used proxy for phytoplankton biomass. Values are derived using the RemoTAP algorithm. In the current version, the variable is named chlor_a, with the long name “Chlorophyll-a concentration, OCI algorithm.” The variable and its long name will be updated in a future release to correctly reference the RemoTAP algorithm. Geophysical variable included: - chlor_a – Chlorophyll concentration (mg m⁻³)
Get the data
import earthaccess
earthaccess.login(strategy="netrc") # free Earthdata Login
results = earthaccess.search_data(
short_name="PACE_SPEXONE_L3M_AER_RTAPOCEAN",
version="3.0",
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 OB_CLOUD Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package. Official links
- OPeNDAP Site for PACE SPEXone Standard Mapped Image (SMI) Product USE SERVICE API
- Earthdata Search allows users to search, discover, visualize, refine, and access NASA Earth Observation data. GET DATA
- View the version history of this product. VIEW RELATED INFORMATION
- NASA's Ocean Color Web - Data Distribution Site GET DATA
- PACE Homepage VIEW RELATED INFORMATION
- SPEXone Homepage VIEW RELATED INFORMATION
- Satellite data procesing can be difficult. We're here to help! Visit the Oceandata Help Hub to navigate learning content for accessing visualizing, and analyzing data products. VIEW RELATED INFORMATION
- Algorithm Theoretical Basis Document for Ocean Properties, RemoTAP Algorithm VIEW RELATED INFORMATION