Ocean weather, biological rates, and unexplained global ecological patterns.

Area of Science:

• Marine Biology
• Oceanography
• Ecology

Background:

• Oceans exhibit significant temporal and spatial temperature variations, termed "ocean weather."
• This variability influences species distribution and abundance but is often overlooked, particularly in tropical regions.
• The paradigm of temperature stability in shallow marine waters (<12.5 m) across latitudes was investigated.

Purpose of the Study:

• To quantify ocean temperature variability across different latitudes and timescales.
• To assess the sensitivity of ectotherms to these temperature variations.
• To explore the link between short-term thermal variability and macroecological patterns.

Main Methods:

• Collated hundreds of in situ, high temporal-frequency ocean temperature time series globally.
• Developed a measure of temperature variability across timescales (quarter-diurnal to annual).
• Calculated biological rate ranges for ectotherms (microbes, algae, animals) based on temperature-dependent exponential relationships.

Main Results:

• Subtropical regions showed the widest temperature ranges at timescales of one month or less.
• Temperate and tropical systems exhibited narrow short-term temperature ranges, suggesting stability.
• Tropical ectotherms displayed greater ranges in temperature-dependent biological rates compared to temperate systems.

Conclusions:

• Tropical ectotherms may possess higher sensitivity to short-term thermal variability.
• Short-term ocean temperature fluctuations could explain previously unexplained macroecological patterns.
• The study challenges assumptions of temperature stability in tropical shallow waters.