For the past two decades, climate change has become an increasingly hot topic in ecology (Hoegh-Guldberg & Bruno, 2010), but our understanding of associated impacts has lagged in marine relative to terrestrial systems (Richardson & Poloczanska, 2008). Specifically, although ecological theory and mathematical modeling have been widely used to project (Box 1) potential ecological responses to future climate-change scenarios (e.g., Cheung et al., 2009; Pike, 2013b), synthesis of observational evidence (Box 1) of such responses to recent climate change has until recently been neglected, especially for ocean systems (Poloczanska et al., 2013). This article is protected by copyright. All rights reserved.