One of the activities carried out at the project is to collect data on weather conditions. Each day, data on air temperature (maximum, minimum and instant temperature), general weather conditions (sunny, cloudy or rainy), tide level and sea temperature, is collected.
Data collected on air temperature during seasons 2006 to 2019 show an increase of the air temperature, minimum and maximum, from season 2015 onwards. The average minimum temperature raised significantly, by +3°C and the maximum by +2°C. Please see these recordings on the graph below.“Marine turtles occupy a wide range of different habitat types throughout their life history (Fig: 1), including temperate and tropical sandy beaches, oceanic frontal systems and gyres, coastal mangrove forests, neritic reefs, seagrass beds and other shallow foraging areas (Musick & Limpus 1997). During their development, marine turtles may cross entire ocean basins, and adults and juveniles have been shown to interact with major oceanic surface currents (Hawkes et al. 2006, Polovina et al. 2006, Seminoff et al. 2007, Shillinger et al. 2008). Temperature is of profound importance as an environmental factor for marine turtles, affecting features of their life history from hatchling sex determination (Yntema & Mrosovsky 1980) to adult distribution (Spotila & Standora 1985, Seebacher & Franklin 2005). Other climatic aspects, such as extreme weather events, precipitation, ocean acidification and sea level rise also have potential to affect marine turtle populations “(Hawkes et al., 2009).
Fig 1: The breeding and nesting phase of marine turtles. The dotted grey arrows represent the potential climate variables and their indirect effects. + or – indicate the likely direction of effect (Hawkes et al., 2009).
According to E. S. Poloczanska et al., 2009 (Advances in Marine Biology, Volume 56) “average global surface temperatures have risen by 0.74°C, over the hundred years since 1906, with warming in recent decades being the most rapid (Trenberth et al., 2007). Eleven of the twelve warmest years since records began in 1850 (to 2006) occurred from 1995 onwards (Trenberth et al., 2007). Warm days and nights have become more frequent over most land areas over the past few decades and are projected to continue to increase in frequency while the frequencies of cold extremes are declining (IPCC, 2007; Shiogama et al., 2007). The Northern Hemisphere is warming much faster than the Southern Hemisphere and surface air temperatures are rising faster over land than over the ocean (Hansen et al., 2006; IPCC, 2007). Warming air temperatures may impact the hatching success and hatchling sex ratios of marine turtles globally.
Ocean temperatures have also been rising, albeit at a slower rate than air temperatures, given the large thermal capacity of the oceans. Over the last 50 years, the ocean temperature has risen by 0.1°C to depths of 700 m.”
“The question is, can marine turtles adapt to future climate change, given the rapid projected rates of global warming in the coming century? Rapid climate change coupled with high anthropogenic impacts on turtle populations, particularly pollution and high mortality through directed harvest and bycatch in fisheries, may seriously comprise the ability of turtle populations to adapt to our changing climate. On the other hand, climate change may benefit marine turtle populations through expansion of potential nesting and foraging areas and increased food supplies for various life stages. Impacts on trophic resources and key habitats such as open-ocean gelatinous zooplankton, seagrass beds and coral reefs may be critical for marine turtles.”
“The cumulative effects of other human-induced stressors may seriously reduce the capacity of some turtle populations to cope with the additional stressor of climate change. The widespread and global nature of many of the anthropogenic-induced stressors means that many turtle populations may be threatened at every life stage. Conservation efforts targeting critical life stages or highly threaten populations should increase resilience.”(E. S. Poloczanska et al., 2009. Advances in Marine Biology, Volume 56)