Field programme · Climate Change
Seawater temperature refers to the thermal measurements taken from the sea surface down through the water column and should not be confused with air temperature.
Photo: Akdeniz Koruma Vakfı Arşivi
Seawater temperature refers to the thermal measurements taken from the sea surface down through the water column and should not be confused with air temperature.
In the Mediterranean, surface water temperatures generally range between 26–29°C during the summer, although seasonal and regional variations are significant.
Between August and September 2023, temperatures of 27–29°C were recorded at depths of up to 30 m, and during October 2023, 26°C was measured even at 40 m depth.
To track thermocline levels, temperature profiles and temporal changes, temperature loggers are placed every 5 metres and record hourly data.
Seawater temperature refers to the thermal measurements taken from the sea surface down through the water column and should not be confused with air temperature. Compared to the atmosphere, the sea warms and cools more slowly; however, these changes can have far more critical consequences for marine life. In the Mediterranean, surface water temperatures generally range between 26–29°C during the summer, although seasonal and regional variations are significant. In coastal areas such as Gökova, Fethiye, and Kaş, these variations can be observed both across depths and throughout the season.
Elevated temperatures disrupt the reproduction, migration and survival cycles of native species.
Invasive species originating from the Red Sea and Indian Ocean are more tolerant to these changes and can spread rapidly into new areas.
For example, the range of seagrass meadows such as Posidonia oceanica may shrink rapidly with rising temperatures.
A decline in species diversity can lead to broken food webs and losses in ecological and economic services.
Exceptional increases in seawater temperature cause corals to expel the symbiotic algae (zooxanthellae) living in their tissues. The loss of these algae causes corals to lose their colour, starting a process known as bleaching. This weakens the corals' energy production and immune systems and can eventually lead to their death. If the temperature increase persists for a long time, coral reef ecosystems suffer serious losses in species diversity and fish populations.
This affects not only corals but also foundational ecosystems such as seagrass meadows. The degradation of seagrass meadows triggers cascading effects, including a reduction in carbon storage capacity, increased coastal erosion and loss of habitat for marine life.
30 mDepth to which the thermocline dropped in 2023 (25 m in 2022)
Seawater temperature monitoring
To understand the impacts of climate change on coastal and marine ecosystems, the Mediterranean Conservation Society began seawater temperature monitoring in Gökova Bay in 2015. In 2020, Fethiye-Göcek and Kaş-Kekova, and in 2022, the Datça-Bozburun SEPA areas were added to the monitoring network.
To track thermocline levels, temperature profiles and temporal changes, temperature loggers are placed every 5 metres and record hourly data.
Since 2015, the collected data have been shared with the T-MEDNet initiative, an observation network on the effects of climate change on coastal marine ecosystems. These contributions support the large-scale, long-term application of standardised monitoring protocols for seawater temperature and biological indicators.
Monitoring data from Gökova validate the reliability of model-based (CMEMS) and satellite data for depths of 0–40 m (Bengil et al., 2021). These data feed into the management plans of protected areas and into climate change adaptation strategies.
To understand the impacts of climate change on coastal and marine ecosystems, the Mediterranean Conservation Society began seawater temperature monitoring in Gökova Bay in 2015. In 2020, Fethiye-Göcek and Kaş-Kekova, and in 2022, the Datça-Bozburun SEPA areas were added to the monitoring network.
To track thermocline levels, temperature profiles and temporal changes, temperature loggers are placed every 5 metres and record hourly data.
Since 2015, the collected data have been shared with the T-MEDNet initiative, an observation network on the effects of climate change on coastal marine ecosystems. These contributions support the large-scale, long-term application of standardised monitoring protocols for seawater temperature and biological indicators.
Monitoring data from Gökova validate the reliability of model-based (CMEMS) and satellite data for depths of 0–40 m (Bengil et al., 2021). These data feed into the management plans of protected areas and into climate change adaptation strategies.
