The international PP242 is undertaking a number of different assessment efforts. The United Nations World Ocean Assessment, for example, has taken a leading role and provided an “Outline for the First Global Integrated Marine Assessment”, which set a clear direction for future assessment research (www.worldoceanassessment.org). Over 70% of the planet is covered by oceans and seas, of which over 60% can be considered open oceans. Many of the world\'s coastal areas have not been protected until the point of over-exploitation has been surpassed for mineral and biological resources. At the same time, human influence on open ocean ecosystems has continued to expand, and has even accelerated for certain services that have been under management for an extended time period (Doney, 2010 and Worm et?al., 2006). The ocean\'s provisioning services, specifically in terms of food, are the most widely studied OPES, and some studies have argued that degradation has occurred over the past fifty years due to direct catch activities (Myers and Worm, 2003 and Pauly et?al., 1998) and indirect climate change impacts (Cheung et?al., 2013 and Perry et?al., 2005). Human activities in terrestrial areas have also impacted marine environments, ultimately contributing to an increasing rate of global climate change (IPCC, 2007, Kroeker et?al., 2012 and Wu et?al., 2014). Such changes are transferred to the open oceans and accumulate over decades or even centuries through biogeochemical cycles (Doney, 2010 and Doney et?al., 2009). A variety of changes in ecosystem services can therefore ultimately feed back into human economic activities (Stern, 2007 and Tol, 2009). Geoengineering1 measures have been repeatedly proposed to take the initiative in mitigating such impacts (Keith, 2000 and MacMynowski et?al., 2011).
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