Do climate change experiments yield relevant insights into responses to chronic ocean warming?

Area of Science:

• Marine Biology
• Climate Change Ecology
• Oceanography

Background:

• Ocean biodiversity is threatened by climate change.
• Predicting marine species' responses to chronic warming is crucial.
• Experimental warming studies often increase temperatures rapidly, potentially affecting results.

Purpose of the Study:

• To investigate if the rate of temperature increase (ramping rate) affects marine species' responses to experimental warming.
• To determine the relative importance of ramping rate versus temperature magnitude on ecological responses.

Main Methods:

• A meta-analysis of 175 experiments from 48 studies on marine species' responses to warming.
• Systematic review to categorize experiments based on ramping rate (none, fast, slow).
• Analysis of effects on reproduction, survival, abundance, and photosynthesis.

Main Results:

• Ramping rate modulated responses: slower warming attenuated reproduction decline and altered abundance effects.
• Survival decreased regardless of ramping rate.
• Photosynthesis declined with slower warming rates.
• Temperature magnitude was a more consistent driver than ramping rate, but their importance varied by response.

Conclusions:

• Many current experiments simulate acute heat stress rather than chronic warming.
• Marine communities experiencing natural warming provide better insights into chronic effects.
• Future research should consider realistic warming rates to accurately predict climate change impacts on oceans.