General questions: are there barriers for cross-breeding in the oceans?

Implications for evolutionary study (e.g., species stability), ecology (e.g., local diversity) and conservation ecology (protected area design, fishery management, invasibility in climate change, etc)

Cover by C. Paris Group

Three components of resilience emerge from the literature. The first is the amount of change a system can undergo and still retain the same controls on structure and functioning (i.e., resistance). In the context of climate change, this component refers to an ecosystem's ability to persist despite increasingly frequent and severe pulse disturbances, such as storms and heat waves. The second component is a system's capacity for recovery and self-organization (versus vulnerability to organization by external factors) following disturbance. The final component is the degree to which a system can adapt to new conditions, such as higher air temperatures or lower ocean pH.

Ecological resilience to climate change is a combination of resistance to increasingly frequent and severe disturbances, capacity for recovery and self-organization, and ability to adapt to new conditions. There are three broad categories of ecological properties that underlie resilience: diversity, connectivity, and adaptive capacity.

1) Diversity increases the variety of responses to disturbance and the likelihood that species can compensate for one another.

2) Connectivity among species, populations, and ecosystems enhances capacity for recovery by providing sources of propagules, nutrients, and biological legacies.

3) Adaptive capacity includes a combination of phenotypic plasticity, species range shifts, and microevolution.

The process of evolutionary rescue occurs when genetic adaptation allows a population to recover from decline initiated by environ- mental change that would otherwise cause extirpation.

Invasibility: the local mechanism driving community assembly and species diversity (?)‘‘invasibility’’: the susceptibility of an environment to the colonization and establishment of individuals from species not currently part of the resident community (Davis et al., Ecogeography, 2005)

Meta-community dynamics

(physical disturbance, etc)

“Our results suggest that variability in the upstream Agulhas Current hydrography is strongly linked to the dynamics of the Agulhas Return Current and that downstream variability in the leakage area (Atlantic sector) at least partly reflects regional variations of the Agulhas Current as a whole.”

“The surface signature of the Agulhas rings propagating across the South Atlantic Ocean is observed based on 3 independent datasets: TMI/AMSR-E satellite sea sur- face temperature, Argo profiling floats and a merged winds product derived from scatterometer observations and reanalysis results. A persistent pattern of cold (negative) SST anomalies in the eddy core, with warm (positive) anomalies at the boundary is revealed.”

For the Southern Hemisphere (SH), CMIP5 models project clear poleward migration, upward expansion, and intensification of the storm track.Consistent with these, CMIP5 models project significant increase in the frequency of extreme cyclones during the SH cool season,but significant decrease in such events in the NH.

SLP variance (over 24h):Climatology and projections

Three main elements compose the potential response of migration to climate change:

Lateral transportLight availabilityMixing and turbulence

General predictions from observations and numerical simulations for the subtropical gyres:

Warmer, bigger sub-tropical gyres, more acid, more extreme atmospheric events.

Specific features on the Agulhas region and Cape Basin:

Higher flow from the indian to the Atlantic and warming of WBCHigher mixing and heat losses due to increased storminessHigher light availability