Potential for Regional Resilience to Ocean Warming and Acidification Extremes: Projected Vulnerability Under...

Area of Science:

• Marine biology
• Climate science
• Oceanography

Background:

• Projected ocean warming and acidification pose significant threats to marine ecosystems.
• Understanding the frequency and amplitude of these extremes is crucial for predicting future impacts.

Purpose of the Study:

• To analyze projected warming and ocean acidification extremes under high CO2 and mitigating scenarios.
• To investigate how methodological choices influence these projections.

Main Methods:

• Analysis of projected frequency and amplitude of warming and acidification extremes.
• Comparison of absolute versus distribution-based thresholds for stressor specification.
• Inclusion/exclusion of seasonal variability and fixed/adaptive baselines in analysis.

Main Results:

• Methodological choices, such as threshold specification and baseline definition, lead to divergent regional patterns in projected stress.
• The choice of baseline significantly alters the comparison of future stress frequency to historical or high-emission scenarios.

Conclusions:

• Emissions reduction mitigation, coupled with realistic adaptation rates, can substantially reduce end-of-century threshold exceedance.
• Mitigation efforts can shift projected stress frequencies closer to historical levels, rather than high-emission scenarios.