Articles | Volume 21, issue 6
https://doi.org/10.5194/os-21-3003-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-21-3003-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
ENSO and the Temperature of the North Equatorial Counter Current
National Oceanography Centre, Southampton SO14 3ZH, UK
Related authors
David John Webb
EGUsphere, https://doi.org/10.5194/egusphere-2024-3560, https://doi.org/10.5194/egusphere-2024-3560, 2024
Preprint withdrawn
Short summary
Short summary
A modern climate model is used to test the hypothesis that changes observed during El Niños are, in part, forced by changes in the temperature of the North Equatorial Counter Current. This is a warm current that flows eastwards across the Pacific, a few degrees north of the Equator, close to the Inter-Tropical Convection Zone, a major region of deep atmospheric convection. The tests generate a significant El Niño type response in the ocean, giving confidence that the hypothesis is correct.
David J. Webb
Ocean Sci., 17, 1585–1604, https://doi.org/10.5194/os-17-1585-2021, https://doi.org/10.5194/os-17-1585-2021, 2021
Short summary
Short summary
Research on strong El Niños has shown that they may be a result of a stronger-than-normal North Equatorial Counter Current, itself triggered by lower-than-normal sea levels that develop early in the year. A numerical model study of the 1981–1982 El Niño shows that the low sea levels are due to local winds in the west Pacific, and this is shown also to be true for the 1997–1998 and 2015–2016 El Niños. As a result, we now have a much better understanding of the mechanism causing strong El Niños.
David John Webb
EGUsphere, https://doi.org/10.5194/egusphere-2024-3560, https://doi.org/10.5194/egusphere-2024-3560, 2024
Preprint withdrawn
Short summary
Short summary
A modern climate model is used to test the hypothesis that changes observed during El Niños are, in part, forced by changes in the temperature of the North Equatorial Counter Current. This is a warm current that flows eastwards across the Pacific, a few degrees north of the Equator, close to the Inter-Tropical Convection Zone, a major region of deep atmospheric convection. The tests generate a significant El Niño type response in the ocean, giving confidence that the hypothesis is correct.
David J. Webb
Ocean Sci., 17, 1585–1604, https://doi.org/10.5194/os-17-1585-2021, https://doi.org/10.5194/os-17-1585-2021, 2021
Short summary
Short summary
Research on strong El Niños has shown that they may be a result of a stronger-than-normal North Equatorial Counter Current, itself triggered by lower-than-normal sea levels that develop early in the year. A numerical model study of the 1981–1982 El Niño shows that the low sea levels are due to local winds in the west Pacific, and this is shown also to be true for the 1997–1998 and 2015–2016 El Niños. As a result, we now have a much better understanding of the mechanism causing strong El Niños.
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Short summary
A modern climate model is used to test a new hypothesis that changes observed during El Niños are, in part, forced by changes in the temperature of the North Equatorial Counter Current. This is a warm current that flows eastwards across the Pacific, a few degrees north of the Equator, close to the Inter-Tropical Convection Zone, a major region of deep atmospheric convection. The test runs show significant El Niño type responses, giving confidence that the hypothesis is correct.
A modern climate model is used to test a new hypothesis that changes observed during El Niños...