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Full catalog/OMG_L2_AXCTD
OMG_L2_AXCTD·v1·dataset

Ocean temperature and saltiness by depth, dropped from aircraft

OMG Airborne eXpendable Conductivity Temperature Depth (AXCTD) Profiles
ocean NASA POCLOUD Level 2 netCDF-4
In plain English

What it measures. Direct measurements of ocean temperature and saltiness at different depths in the water near Greenland, along with water density and the speed of sound through the water.

How it's made. Probes were dropped from an airplane; after splashing down, each sensor sank at a known rate, recording temperature and conductivity as it fell, which were then converted into salinity and depth.

How & where you'd use it. Part of the Oceans Melting Greenland mission, helping scientists understand how ocean water is contributing to the melting of Greenland's glaciers, in places ships can't easily reach.

What's measured

OCEANS › SALINITY/DENSITY › DENSITYOCEANS › OCEAN TEMPERATURE › TEMPERATURE PROFILES › NONEOCEANS › SALINITY/DENSITY › SALINITYOCEANS › SALINITY/DENSITY › CONDUCTIVITY

Coverage & cadence

  • Time span2016-09-13 → 2021-12-31
  • Measured byAircraft (AXCTD)
  • Processing levelLevel 2
  • Spatial extent73.6, 59.1, 180, 83.6
  • FormatsnetCDF-4
  • StatusCOMPLETE

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 in situ profile measurements from Airborne eXpendable Conductivity Temperature Depth (AXCTD) probes. It provides salinity, density, temperature and sound velocity as a function of depth in the water column. The AXCTDs were jettisoned from a plane to collect temperature and salinity readings around Greenland, where a ship would have had difficulties maneuvering. After landing in the water, the AXCTDs drop a weighted sensor from the surface that falls at a well-calibrated rate, measuring water temperature and conductivity as it falls. An equation is used to determine the depth of the measurements as the probe falls, and another equation is used to convert temperature, depth and conductivity into salinity. These probes provided measurements of the ocean's physical characteristics around Greenland, where a ship would have had difficulties maneuvering. The AXCTDs are part of the Oceans Melting Greenland (OMG) mission. The AXCTDs were deployed in the fall from 2016 through 2021, covering the entire continental shelf surrounding Greenland as part of a once-per-year survey. The goal of the mission is to find out what contributions the ocean has on Greenland's melting glaciers.

Get the data

omg_l2_axctd_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMG_L2_AXCTD",
    version="1",
    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.