Global and regional change clearly affects the structure and functioning of ecosystems in shelf seas. However, complex interactions within the shelf seas hinder the identification and unambiguous attribution of observed changes to drivers. These include variability in the climate system, in ocean dynamics, in biogeochemistry, and in shelf sea resource exploitation in the widest sense by societies. Observational time series are commonly too short, and resolution, integration time, and complexity of models are often insufficient to unravel natural variability from anthropogenic perturbation. The North Sea is a shelf sea of the North Atlantic and is impacted by virtually all global and regional developments. Natural variability (from interannual to multidecadal time scales) as response to forcing in the North Atlantic is overlain by global trends (sea level, temperature, acidification) and alternating phases of direct human impacts and attempts to remedy those. Human intervention started some 1000 years ago (diking and associated loss of wetlands), expanded to near-coastal parts in the industrial revolution of the mid-19th century (river management, waste disposal in rivers), and greatly accelerated in the mid-1950s (eutrophication, pollution, fisheries). The North Sea is now a heavily regulated shelf sea, yet societal goals (good environmental status versus increased uses), demands for benefits and policies diverge increasingly. Likely, the southern North Sea will be re-zoned as riparian countries dedicate increasing sea space for offshore wind energy generation – with uncertain consequences for the system's environmental status. We review available observational and model data (predominantly from the southeastern North Sea region) to identify and describe effects of natural variability, of secular changes, and of human impacts on the North Sea ecosystem, and outline developments in the next decades in response to environmental legislation, and in response to increased use of shelf sea space.

@article{TNSASSITAE15,
	author	 = {Kay-Christian Emeis and Justus van Beusekom and Ulrich Callies and Ralf Ebinghaus and Andreas Kannen and Gerd Kraus and Ingrid Kröncke and Hermann Lenhart and Ina Lorkowski and Volker Matthias and Christian Möllmann and Johannes Pätsch and Mirco Scharfe and Helmuth Thomas and Ralf Weisse and Eduardo Zorita},
	title	 = {{The North Sea -- A shelf sea in the Anthropocene}},
	year	 = {2015},
	editor	 = {},
	publisher	 = {Elsevier Science Publishers B. V.},
	address	 = {Amsterdam, The Netherlands},
	journal	 = {Journal of Marine Systems},
	series	 = {141},
	pages	 = {18--33},
	doi	 = {http://dx.doi.org/10.1016/j.jmarsys.2014.03.012},
	abstract	 = {Global and regional change clearly affects the structure and functioning of ecosystems
      in shelf seas. However, complex interactions within the shelf seas hinder the identification
      and unambiguous attribution of observed changes to drivers. These include variability in the
      climate system, in ocean dynamics, in biogeochemistry, and in shelf sea resource exploitation
      in the widest sense by societies. Observational time series are commonly too short, and
      resolution, integration time, and complexity of models are often insufficient to unravel
      natural variability from anthropogenic perturbation. The North Sea is a shelf sea of the North
      Atlantic and is impacted by virtually all global and regional developments. Natural
      variability (from interannual to multidecadal time scales) as response to forcing in the North
      Atlantic is overlain by global trends (sea level, temperature, acidification) and alternating
      phases of direct human impacts and attempts to remedy those. Human intervention started some
      1000 years ago (diking and associated loss of wetlands), expanded to near-coastal parts in the
      industrial revolution of the mid-19th century (river management, waste disposal in rivers),
      and greatly accelerated in the mid-1950s (eutrophication, pollution, fisheries). The North Sea
      is now a heavily regulated shelf sea, yet societal goals (good environmental status versus
      increased uses), demands for benefits and policies diverge increasingly. Likely, the southern
      North Sea will be re-zoned as riparian countries dedicate increasing sea space for offshore
      wind energy generation -- with uncertain consequences for the system's environmental status.
      We review available observational and model data (predominantly from the southeastern North
      Sea region) to identify and describe effects of natural variability, of secular changes, and
      of human impacts on the North Sea ecosystem, and outline developments in the next decades in
      response to environmental legislation, and in response to increased use of shelf sea space.},
	url	 = {http://www.sciencedirect.com/science/article/pii/S0924796314000724},
}