Seawater temperature data from a subtidal habitat in Elands Bay, 1 to 31 January 2024

To better understand the physiological effects of climate change and ocean acidification on marine organisms, information on the environmental conditions experienced in their natural habitats is required. Data from long-term monitoring studies capture in situ variability of environmental parameters that are used to relate experimental findings with field conditions. Elands Bay on the west coast of South Africa is a key location for such research and monitoring. It is a popular location for West Coast rock lobster fishing and therefore an important sentinel site for a commercial fishery species and the benthic communities upon which it depends. Low pH conditions exist along the west coast due to effects of upwelling, while cold-bottom waters in Elands Bay often result in low oxygen events responsible for mass walkouts of rock lobster. Additional exposure to extreme stressors associated with climate change can exacerbate impacts on their physiological processes. For example, acute thermal stress experienced during a marine heatwave may cause a rapid deterioration of cellular processes and performances beyond tolerance limits, affecting survival, growth and development. In South Africa, occurrences of marine heatwaves are increasing all along the coastline, and occur on average at least once a year. Data on temperature extremes are therefore important to design experiments and calculate thermal windows. We initiated long-term monitoring of inshore environmental parameters in Elands Bay by deploying temperature loggers in representative habitat types: intertidal rock pools varying in surface area, volume and position along the shore, sun-exposed habitats, and subtidal habitats. The subtidal logger is positioned at an overhang in the same vicinity of the rockpools and housed in a mooring block. Here we present the cleaned up version of temperature measurements from the subtidal from 1 to 31 January 2024.

为更深入地探讨气候变化及海洋酸化对海洋生物生理效应的影响，需收集其自然栖息地所经历的环境条件信息。长期监测研究的数据记录了现场环境参数的即时变化，这些参数被用于将实验发现与野外条件相关联。南非西海岸的Elands Bay是此类研究和监测的关键地点。它是西海岸岩龙虾捕捞的热门区域，因此对于这一商业渔业物种及其依赖的底栖生物群落而言，是一个重要的指示站。由于上升流的影响，西海岸沿线存在低pH条件，而Elands Bay的冷底层水常常导致低氧事件，这会引发岩龙虾的大规模迁徙。气候变化相关极端压力的额外暴露可能会加剧对其生理过程的影响。例如，在海洋热浪期间经历的急性热应激可能会导致细胞过程和性能迅速恶化，超出耐受极限，影响其生存、生长和发育。在南非，海洋热浪的发生频率沿整个海岸线都在增加，平均每年至少发生一次。因此，温度极端值的数据对于设计实验和计算热窗至关重要。我们通过在代表性栖息地类型中部署温度记录仪，即不同表面积、体积和位置的潮间带岩石池、阳光直射栖息地和潮下带栖息地，启动了对Elands Bay近岸环境参数的长期监测。潮下带记录仪位于岩石池相同区域的岩檐处，并安装在系泊块中。在此，我们展示了2024年1月1日至31日潮下带温度测量的清洁版本。