Patterns and emerging trends in global ocean health

Area of Science:

• Marine biology
• Environmental science
• Conservation science

Background:

• Effective ocean management requires quantitative tools to assess ecosystem health.
• International policies need consistent metrics to track progress and communicate findings.
• The Ocean Health Index (OHI) provides a framework for evaluating marine ecosystem status.

Purpose of the Study:

• To present the second annual global assessment of the OHI for 221 coastal countries and territories.
• To report current OHI scores and annual changes since 2012.
• To provide updated quantitative data on ocean health performance across ten societal goals.

Main Methods:

• Recalculated OHI scores using updated methods and the best available scientific data.
• Assessed performance across ten societal goals for healthy oceans on a scale of 0-100.
• Combined goal scores into a single OHI score for each country and globally.

Main Results:

• The global OHI score improved from 67 to 68.
• Country-level OHI scores ranged from 41-95, with an average improvement of 0.06 points.
• Significant score changes were observed for individual goals, with increases up to 6.5 points (coastal economies) and decreases up to 1.2 points (natural products).

Conclusions:

• Annual OHI updates provide valuable trend information for scientists and policymakers.
• Score changes, even minor ones, highlight areas of success or concern for ocean health.
• The low covariance between goal scores indicates the Index captures diverse facets of ocean health, informing targeted conservation efforts.