Karen Wiltshire: The North Sea in the fast lane of Climate Change: a summary of the science based on the Long Term Data of Helgoland and Sylt

The North Sea in the fast lane of Climate Change: a summary of the science based on the Long Term Data of Helgoland and Sylt

Global warming of coastal and shelf seas is fact. Long-term temperature and climate time series, as well as models, provide the evidence. The pressure is on to provide concurrent data-driven knowledge of ecosystem reactions and stability. It is imperative to translate this warming into evinced and graspable ecosystem effects and consequences; otherwise, management strategies and scenario discussions are difficult/impossible to realise.

Here we will present our findings based on the Long Term Data of Helgoland and Sylt and show that Ecosystems and organisms react to shifts in environments on different time scales. The potential death, fitness, resilience and adaptation of species is dependent on the intensity, duration and frequencies of environmental shifts/ events. Frequently the exact changes in environmental drivers are statistically difficult to grasp in time and spatial scales. Thus, the understanding of and foundation for long-term management of ecosystem and biodiversity shifts in terms of temperature can be scientifically deviant and sometimes tenuous.

We analysed the temperature data from detailed long-term marine ecological time series Helgoland Roads, Sylt Roads and the North Sea with global, continental, regional and local temperature time series. Long-term trends, warming and cooling events, seasonal shifts are identified, and anomalies and frequency distributions of temperature over time evaluated. Plankton, life cycle, and food web interaction information are placed in the ecological context of time and spatial scale.

We discuss a hierarchy of necessary analyses in order to be able to relate marine ecosystem change to temperature in terms of relevant time and spatial scales.