Conclusion

The world’s oceanic algae play a critical role in mitigating global warming, but because of its effects are suffering decline. Through its role in nutrient limitation, stratification increasingly contributes to this decline. Cell size is likely to be important among several factors that confer differential fitness to algal species under environmental conditions that include elevated temperature, UVBR flux and CO₂ concentrations. Selection pressure is likely to cause changes in pelagic community assemblages. This will have important and unpredictable implications for ocean ecosystems more broadly, and may contribute positive feedback to global warming. Scope exists for a great deal more investigation into this field, encompassing as it does facets of phycology, oceanography and ecology. 

Acknowledgements 

I extend my gratitude to John Beardall, School of Biological Sciences, Monash University for his valuable input during the drafting of this paper.