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Full catalog/MERGED_TP_J1_OSTM_OST_GMSL_ASCII_V52
MERGED_TP_J1_OSTM_OST_GMSL_ASCII_V52·v5.2·dataset

How fast global sea level is rising (multi-satellite)

Global Mean Sea Level Trend from Integrated Multi-Mission Ocean Altimeters TOPEX/Poseidon, Jason-1, OSTM/Jason-2, Jason-3, and Sentinel-6 Version 5.2
ocean NASA POCLOUD Level 4 ASCII
In plain English

What it measures. A single long-running time series showing how the global average sea level has changed since 1992, reported relative to a 20-year baseline. In short, it tracks how fast the seas are rising.

How it's made. Stitched together from a series of ocean-measuring radar altimeter satellites (TOPEX/Poseidon, the Jason series, and Sentinel-6), carefully cross-calibrated so the missions line up, with corrections applied for the slow rebound of Earth's crust.

How & where you'd use it. A key climate-change indicator used to monitor and communicate the pace of global sea-level rise.

What's measured

OCEANS › SEA SURFACE TOPOGRAPHY › SEA SURFACE HEIGHT

Coverage & cadence

  • Time span1992-09-01 → ongoing
  • Measured byOSTM/JASON-2 (AMR, POSEIDON-3) · JASON-1 (JASON-1 Microwave Radiometer, POSEIDON-2) · TOPEX/POSEIDON (ALT (TOPEX), TMR, SSALT) · JASON-3 (POSEIDON-3B)
  • Processing levelLevel 4
  • Spatial extent-180, -66, 180, 66
  • FormatsASCII
  • 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 dataset contains the Global Mean Sea Level (GMSL) trend generated from the Integrated Multi-Mission Ocean Altimeter Data for Climate Research Version 5.2. The GMSL trend is a 1-dimensional time series of globally averaged Sea Surface Height Anomalies (SSHA) from TOPEX/Poseidon, Jason-1, OSTM/Jason-2, Jason-3, and Sentinel-6A that covers September 1992 to present with a lag of up to 4 months. The data are reported as variations relative to a 20-year TOPEX/Jason collinear mean. Bias adjustments and cross-calibrations were applied to ensure SSHA data are consistent across the missions; Glacial Isostatic Adjustment (GIA) was also applied. The data are available as a table in ASCII format. Changes between the version 5.1 and version 5.2 releases are described in detail in the user handbook.

Get the data

merged_tp_j1_ostm_ost_gmsl_ascii_v52_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MERGED_TP_J1_OSTM_OST_GMSL_ASCII_V52",
    version="5.2",
    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.