 |
 |  |
|
|||
Home |
World Climate |
Climate System Monitoring |
El Niño Monitoring |
NWP Model Prediction |
Global Warming |
Climate in Japan |
Training Module |
Press release |
Links |
[El Niño / La Niña]In November 2024, the sea surface temperature (SST) for the NINO.3 region was near normal with a deviation of -0.2°C (Fig.3 and Table). The five-month running mean value of the NINO.3 SST deviation for September 2024 was -0.3°C. SSTs in the equatorial Pacific were above normal in the western part and below normal from the central to eastern part (Fig.4 and Fig.6). Subsurface water temperatures in the equatorial Pacific were above normal in the western part, while they were below normal from the central to eastern part (Fig.5 and Fig.7). In the atmosphere, convective activity near the dateline over the equatorial Pacific was less active than normal, and easterly winds in the lower troposphere (i.e., trade winds) over the central equatorial Pacific were slightly stronger than normal, partly due to the tropical intraseasonal oscillation (Fig.8, Fig.9 and Fig.10). These oceanic and atmospheric conditions in the equatorial Pacific comprehensively indicate that ENSO-neutral conditions persisted in November. Overall conditions in the atmosphere and ocean, however, indicate that common features of past La Niña events were becoming clear.
The cold subsurface water volume continued from the central to eastern equatorial Pacific (Fig.5). JMA's seasonal ensemble prediction system predicts that trade winds over the western to central equatorial Pacific will be stronger than normal and the cold subsurface water volume from the central to eastern equatorial Pacific will increase further and propagate eastward. As a result, it is expected that NINO.3 SST will be below normal during boreal winter. However, the conditions will not last long as the atmosphere-ocean coupling weakens, and NINO.3 SST is predicted to come closer to normal towards the coming spring (Fig.11). In conclusion, the characteristics of La Niña conditions will become clearer during winter, but will not last long, and weaken towards boreal spring. Thus, it will not satisfy the JMA's definition of a La Niña Event. In conclusion, it is likely (70%) that ENSO-neutral conditions will persist to boreal spring.
[Western Pacific and Indian Ocean]
The area-averaged SST in the tropical western Pacific (NINO.WEST) region was near normal in November (Fig.3). The index is likely to be mostly above normal during boreal winter, and to be above or near normal during boreal spring (Fig.12).
The area-averaged SST in the tropical Indian Ocean (IOBW) region was above normal in November (Fig.3). The index is likely to be near or below normal until boreal spring (Fig.13).
The seasonal climate outlook for Japan is available here .
