POSTER SESSION 3
15:30–17:30, Wednesday, September 16
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
ABSTRACT 1206 | POSTER 251
ENSO-INDUCED VARIATIONS IN PACIFIC OCEAN SURFACE ALBEDO AND ASSOCIATED DRIVING MECHANISMS
Ocean surface albedo (OSA) is a key regulator of the air-sea energy balance, yet its impacts and feedbacks under ongoing climate change and increasingly frequent extreme events remain poorly understood. In this study, we examine the potential responses of OSA to El Niño-Southern Oscillation (ENSO) events over the central-western equatorial Pacific (CWEP, 120–190°E, 5°S–5°N) using MODIS-AQUA and ERA5 data from 2003 to 2020. Our results show that the response of OSA to ENSO exhibits distinct spatial variability. It is positively correlated with the Niño3.4 index in the central equatorial Pacific (CEP, 155–190°E, correlation coefficient (r) = 0.68), while negatively correlated in the western equatorial Pacific (WEP, 120–155°E, r = −0.46). Moreover, the magnitude of OSA anomalies in the WEP is approximately 45% higher than in the CEP during ENSO episodes. Time-series observations show a general pattern that, prior to El Niño onset, WEP generally exhibits negative OSA anomalies (5%–10%), which contribute to enhanced shortwave radiation absorption and SST warming, whereas CEP exhibits positive anomalies (10%–13%) that potentially reduce radiation absorption and suppress warming. This spatial contrast may weaken the zonal SST gradient and cross-region pressure differences in the CWEP, leading to anomalous weakening of the southeast trade winds. Based on these preliminary results, we hypothesize that OSA variations may enhance spatial contrasts in the radiation budget across CWEP during ENSO, induce a weak negative feedback on wind speed, and ultimately contribute to climatic anomalies.
LT Yu*, Xianmen University, [email protected]
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
