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Full catalog/HOMAGE_GGFO_L4_GOMA_Monthly_v01
HOMAGE_GGFO_L4_GOMA_Monthly_v01·v1.0·dataset

Monthly changes in total ocean water mass (GRACE)

GRACE/GRACE-FO Level-4 Monthly Global Ocean Mass Anomaly version 01 from NASA MEaSUREs HOMaGE project
ocean NASA POCLOUD Level 4 netCDF-4
In plain English

What it measures. Month-to-month changes in the total mass of water in the global ocean, expressed as anomalies (departures from a baseline) since April 2002.

How it's made. Derived from the GRACE and GRACE-FO satellite missions, which sense tiny shifts in Earth's gravity; the gravity fields are averaged over the ocean and corrected for atmosphere and slow crustal rebound.

How & where you'd use it. Lets scientists track how much water the ocean is gaining, which relates to melting land ice and sea level rise, and supports climate and sea-level research.

What's measured

OCEANS › OCEAN PRESSURE › OCEAN BOTTOM PRESSURECLIMATE INDICATORS › ATMOSPHERIC/OCEAN INDICATORS › SEA LEVEL RISEOCEANS › SEA SURFACE TOPOGRAPHY › SEA LEVEL › SEA LEVEL ANOMALY

Coverage & cadence

  • Time span2002-04-17 → ongoing
  • Measured byGRACE-FO · GRACE
  • Processing levelLevel 4
  • 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 data set contains the monthly Global Ocean Mass Anomalies (goma) since 04/2002, as measured by the GRACE and GRACE Follow-On (G/GFO) satellite missions. The data are averaged over the global ocean domain, at monthly intervals (note: data gaps exist). This file contains the goma time series based on the spherical harmonic gravity fields provided by the G/GFO SDS centers: JPL, CSR, GFZ. The data are frequently updated as new monthly observations are acquired by the GFO mission. The processing of the spherical harmonics gravity field coefficients is as follows: (1) GAD + GSM: the monthly de-aliasing product GAD is added back to the GSM L2 gravity fields; (2) [GSM + GAD] coefficients are averaged over the global ocean with a coastal buffer of 300 km (to avoid land-ocean leakage); (3) the spatial mean of atmospheric loading of the entire global ocean domain is removed (via the GAA L2 data product). A GIA correction using the ICE-6GD model (Peltier et al., 2018) is applied.

Get the data

homage_ggfo_l4_goma_monthly_v01_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="HOMAGE_GGFO_L4_GOMA_Monthly_v01",
    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.