The ocean is a dynamic and rapidly evolving environment, a
long-appreciated truth which becomes increasingly apparent as
we observe it ever more carefully. Some of the
transformations that we see are ones we are causing, and some
are new to us only because we are looking in greater detail
and with more sophisticated tools. This special issue
contains a series of Reviews and News pieces that highlight
some of the ways in which we see our oceans changing. Lozier
(p. 1507)
discusses how recent studies have challenged our view of
large-scale ocean circulation as a simple conveyor belt, by
revealing a more complex and nuanced system that reflects the
effects of ocean eddies and surface atmospheric winds on the
structure and variability of the ocean's overturning. Next, Doney
(p. 1512)
reviews how the chemistry of the oceans is changing, mostly
due to human fossil fuel combustion, fertilizer use, and
industrial activity. Nicholls and Cazenave (p. 1517)
present an overview of recent sea-level rise, its impacts on
coastal regions, and how adaptation may lessen those
impacts. Two pieces examine how climate change is affecting
marine biological systems: Schofield et al. (p. 1520)
illustrate and discuss the role of ocean-observation
techniques in documenting how marine ecosystems in the West
Antarctic Peninsula region are evolving, and Hoegh-Guldberg and
Bruno (p. 1523)
present a more global view of the ways in which marine
ecosystems are being affected by rapid anthropogenic variations.