NOXX10 KWBC 151118
Data Mgt Message 09.26-11
To: All Meteorological Services, Climate Researchers, and GTS
Data Users
From: RTH Washington IDP DataFlow and the National Data Buoy
Center

Subject: Data Quality Advisory - TAO Array Wind Speed
Calibration Adjustment

The National Data Buoy Center (NDBC), in collaboration with the
Pacific Marine Environmental Laboratory (PMEL), issues this
advisory regarding wind speed observations from the Tropical
Atmosphere Ocean (TAO) array. Users are advised to use TAO wind
speed data collected between 2020 and the present with caution.
Routine data evaluations and intercomparisons have identified a
high bias in TAO wind speed measurements (averaging +0.5 to +0.8
m/s) when compared to satellite and external reference data.
This bias has been traced to the application of specific wind
tunnel calibration coefficients implemented for deployments
starting in 2020.

To mitigate this bias in real-time data streams and prevent
unintended downstream impacts on weather and climate modeling,
NDBC is adjusting the shoreside processing of this data.
Effective for all buoy deployments after January 01, 2026, all
wind speed data processing is set with a slope of 1 and an
offset of 0. These deployments will rely on factory calibrations
with no additional wind tunnel adjustments.
The following TAO lines have been serviced and equipped with new
anemometers. These moorings will operate without the previously
applied wind tunnel coefficients:

2N 125W/rc045a (WMO 51016)
0 125W/rc046a (WMO 51011)
2S 125W/rc047a (WMO 51017)
5S 140W/rc048a (WMO 51014)
2S 140W/rc049a (WMO 51009)
1S 140W/rc050a (WMO 51025)
0 140W/rc051a (WMO 51311)
1N 140W/rc052a (WMO 51024)
2N 140W/rc053a (WMO 51008)
5N 140W/rc054a (WMO 51007)
9N 140W/rc055a (WMO 51006)

Additionally, the following moorings will be completed by the
end of FY26 The following moorings will have RM Young
Anemometers with factory settings.

10N 165W (WMO 52013)
8N 165E (WMO 52006)
5N 165E (WMO 52003)
2N 165E (WMO 52001)
0 165E (WMO 52321)
2S 165E (WMO 52002)
5S 165E (WMO 52004)
8S 165E (WMO 52007)
8N 180W (WMO 52315)
5N 180W (WMO 52309)
2N 180W (WMO 52310)
0 180W (WMO 52311)
2S 180W (WMO 52312)
5S 180W (WMO 52313)
8S 180W (WMO 52316)
10N 170W (WMO 51312)
8N 170W (WMO 51309)
5N 170W (WMO 51303)
2N 170W (WMO 51305)
0 170W (WMO 51010)
2S 170W (WMO 51306)
5S 170W (WMO 51304)
8S 170W (WMO 51310)
8N 155W (WMO 51301)
5N 155W (WMO 51020)
2N 155W (WMO 51021)
0 155W (WMO 51023)
2S 155W (WMO 51022)
5S 155W (WMO 51019)
8S 155W (WMO 51302)

Note: By the end of 2026, the 95W and 110W lines will be the
only remaining stations utilizing anemometers calibrated in the
NDBC wind tunnel.
NDBC and PMEL are actively conducting land-based evaluations,
sensor exchanges, and NIST-traceable calibrations to establish a
permanent resolution. Historical data sets (2020–present) are
currently under review. Once finalized, corrected historical
datasets and updated metadata will be formally delivered to the
NCEI climate record.

For questions regarding this notice, affected moorings, or the
status of the TAO Wind Speed Calibration Project, please
contact:

National Data Buoy Center
Stennis Space Center Mississippi
Email: webmaster.ndbc@noaa.gov

This information is also posted on the NWS IDP DataFlow
change notices web page. The url is listed below.
https://www.weather.gov/datamgmt/notices

IDP DataFlow
NCO Implementation & Data Services Branch
College Park
GISC/RTH Washington Sends
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