Portsmouth and the Isle of Wight are both iconic destinations in southern England, known for their beautiful coastlines, vibrant maritime history and geological significance. University of Portsmouth PhD student Meriam Chouar invites us into an extraordinary world beneath the beauty of their chalky cliffs and the surrounding waters.
Here dwell creatures invisible to the human eye known as coccolithophores. Though frequently overlooked, these tiny organisms have a significant impact on not only the land but also our understanding of marine life and climate change. They have even served as inspiration to renowned local artists, such as Heinrich & Palmer, in projects such as ‘Once a Sea’, a journey through time and space launched last year at Portsmouth’s We Shine 24 Light Festival.
So, what exactly are coccolithophores? They are algae that produce tiny plates as part of their body, known as coccoliths. Found in oceans worldwide, these life forms are essential at the base of the marine food chain. Their plates are composed of calcium carbonate (chalk),
giving them a hard structure. When coccolithophores die, their plates accumulate on the seafloor, eventually forming vast deposits of chalk.
These tiny organisms are critical to regulating our planet’s carbon exchange as they absorb carbon dioxide (CO2) from the atmosphere. When they die, coccoliths sink to the ocean floor, transporting and storing carbon for a long time, which is one of the natural ways that the Earth regulates its climate. However, like many other oceanic systems, coccolithophores are threatened by human activities, particularly climate change and the acidification of our oceans, which harm marine life.
Despite their small size, coccolithophores have had a long-lasting impact on both Earth’s history and modern marine life. The chalk cliffs of the Isle of Wight and Portsmouth serve as iconic examples of fossilised coccolith remains. These cliffs formed 145 to 66 million years
ago (while Portsmouth was under the sea but dinosaurs roamed on land!) and are rich in chalk plates from coccolithophores that once thrived in the ancient ocean. These rocks contain vital information about past climate conditions, such as ocean temperatures, CO2
levels, and marine life.
Rising ocean temperatures and acidification make it difficult for them to form their plates. This disruption could affect marine food chains and reduce the ocean’s ability to absorb carbon, making climate change worse. As a result, studying coccolithophores is crucial to
understanding how our oceans respond to global warming.
We are studying how climate change and ocean acidification affected these organisms in the past at the University of Portsmouth. Our aim is to gain insights into the long-term effect on marine life and provide important information for the future of our oceans. The chalk cliffs of the Isle of Wight and Portsmouth provide more than just scenic views; they preserve the legacy of coccolithophores and serve as a window into Earth’s climate past. As climate changes over time, protecting marine environments and understanding how coccolithophores and other organisms adapt is essential to ensure the long-term health of our oceans.
Efforts to protect marine life are more urgent than ever. Supporting local conservation efforts and scientific research will ensure that coccolithophores continue to play their important role in stabilising our planet’s climate. The ongoing research at the University of Portsmouth, combined with local conservation programs, provides hope for the future. As the impacts of climate change grow more severe,
understanding and protecting organisms like coccolithophores is the key to maintaining the health of our oceans and minimising the effects of global warming.
Illustration by Heinrich & Palmer.
