Rich Walter A, Carvalho Susana, Berumen Michael L
Red Sea Research Center King Abdullah University of Science and Technology Thuwal Saudi Arabia.
Ecol Evol. 2022 Oct 22;12(10):e9450. doi: 10.1002/ece3.9450. eCollection 2022 Oct.
Ocean warming is leading to more frequent coral bleaching events. However, cold stress can also induce bleaching in corals. Here, we report observations of a boreal winter bleaching event in January 2020 in the central Red Sea, mainly within a population of the branching coral on an offshore reef flat. Sea surface temperatures (SSTs) rarely fall below 24°C in this region, but data loggers deployed on several nearby reef flats recorded overnight seawater temperatures as low as 18°C just 3 days before the observations. The low temperatures coincided with an extremely low tide and cool air temperatures, likely resulting in the aerial exposure of the corals during the night time low-tide event. The risk of aerial exposure is rare in winter months, as the Red Sea exhibits seasonal fluctuations in sea level with winter values typically 0.3-0.4 m higher than in summer. These observations are notable for a region typically characterized as a high-temperature sea, and highlight the need for long-term monitoring programs as this rare event may have gone unnoticed.
海洋变暖正导致珊瑚白化事件愈发频繁。然而，冷应激也会引发珊瑚白化。在此，我们报告了2020年1月红海中部发生的一次寒季白化事件的观测情况，主要发生在近海礁坪上的一个分支珊瑚种群中。该区域的海面温度（SST）很少会降至24°C以下，但部署在附近几个礁坪上的数据记录器在观测前3天记录到夜间海水温度低至18°C。低温与极低的潮汐和凉爽的气温同时出现，这可能导致珊瑚在夜间低潮期时暴露于空气中。在冬季，珊瑚暴露于空气中的风险很少见，因为红海海平面存在季节性波动，冬季的海平面通常比夏季高0.3 - 0.4米。这些观测结果在一个通常被视为高温海域的地区值得关注，并凸显了长期监测计划的必要性，因为这一罕见事件可能未被注意到。
