Earth Data School
About
Full catalog/MERIS_L3m_CYAN
MERIS_L3m_CYAN·v6.0·dataset

Harmful blue-green algae blooms in water (Envisat MERIS)

ENVISAT MERIS Regional Mapped Cyanobacteria Index (CI) Data, version 6.0
biosphere NASA OB_CLOUD Level 3 netCDF-4
In plain English

What it measures. An index that flags waters dominated by cyanobacteria, the blue-green algae behind many harmful blooms, covering the contiguous United States and Alaska. The standard product is filtered to show only cyanobacteria-dominated water.

How it's made. Derived from the MERIS color instrument on Europe's Envisat satellite, processed into a regionally mapped index designed for quick use by water managers.

How & where you'd use it. Helps water-quality managers and researchers monitor freshwater harmful algal blooms in lakes and reservoirs.

What's measured

BIOLOGICAL CLASSIFICATION › BACTERIA/ARCHAEA › CYANOBACTERIA (BLUE-GREEN ALGAE)OCEANS › WATER QUALITY › ALGAL BLOOMS › HARMFUL ALGAL BLOOM (HABs)OCEANS › WATER QUALITY › ALGAL BLOOMSTERRESTRIAL HYDROSPHERE › WATER QUALITY/WATER CHEMISTRY › WATER CHARACTERISTICS › WATER COLOREARTH SCIENCE SERVICES › ENVIRONMENTAL ADVISORIES › HYDROLOGICAL ADVISORIES › WATER QUALITYTERRESTRIAL HYDROSPHERE › SURFACE WATER

Coverage & cadence

  • Time span2002-03-21 → 2012-05-09
  • Measured byENVISAT (MERIS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsnetCDF-4
  • StatusCOMPLETE

What you can do with it

  • Map vegetation, forests and biomass
  • Monitor ecosystem productivity and carbon
  • Support habitat and biodiversity studies
Official description

CyAN CI delivers the Cyanobacteria Index for contiguous U.S. (CONUS) and Alaska. The standard product is CI_cyano, which is filtered for cyanobacteria dominated waters only. Products are designed for fast ingest by water-quality managers and researchers monitoring freshwater HABs. The algorithm and processing details are documented in the official release notes. Geophysical variables in this suite include: - band1 – Cyanobacteria Index (DN-encoded) (digital number, unitless)

Get the data

meris_l3m_cyan_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MERIS_L3m_CYAN",
    version="6.0",
    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.