In:
Bulletin of the American Meteorological Society, American Meteorological Society, Vol. 102, No. 10 ( 2021-10), p. E1862-E1877
Abstract:
In 1976, a pilot experiment, called first Equatorial Mooring (EQUA-1), tested an innovative technique for anchoring a taut-line surface mooring at 0°, 150°W where the water depth is 4.5 km. The 36-day deployment contained a wind recorder and fixed-level current meters at 50 and 100 m in the Equatorial Undercurrent (EUC). The following year, in a second pilot experiment, named EQUA-2, a similar mooring was deployed at 0°, 125°W for 99 days. EQUA-2, with current meters at 10, 50, 100, 150, and 200 m, recorded a surge in EUC transport during April 1977 when 3-day-averaged eastward current speeds at 50-m depth reached 2 m s −1 . The associated eastward transport per unit meridional width over the 50–200-m layer was 190 m 2 s −1 . Based on observations recorded in April 1980, the EQUA-2 pulse would correspond to a total EUC transport surge of about 38 Sv (1 Sv ≡ 10 6 m 3 s −1 ) and would represent an equatorially trapped first-mode baroclinic Kelvin wave. This paper describes EQUA Project observations and why and how I created the high-risk-of-failure opportunity to record pioneering time series measurements at the equator. The enduring legacy of the EQUA Project is the sustained maintenance of in situ surface wind and upper-ocean current and temperature measurements at numerous sites in the equatorial oceans, starting in the Pacific to improve forecasts of the El Niño and La Niña phenomenon. For example, the 40-yr records of surface wind and upper-ocean current and temperature measurements at 0°, 110°W and 0°, 140°W are some of oceanography’s longest time series recorded far from land.
Type of Medium:
Online Resource
ISSN:
0003-0007
,
1520-0477
DOI:
10.1175/BAMS-D-20-0314.1
Language:
Unknown
Publisher:
American Meteorological Society
Publication Date:
2021
detail.hit.zdb_id:
2029396-3
detail.hit.zdb_id:
419957-1
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