Sea levels rising at an accelerated pace, oceans becoming more acidic and Arctic ice retreating, but by how much?  The fourth Ocean State Report is essential reading for all of us.

The world’s attention may be diverted by the ongoing coronavirus pandemic but another crisis continues to build regardless.

Climate change and its impact on life as we know it remains as urgent as ever. It is timely, therefore, that the EU’s satellite Earth Observation Programme, Copernicus, should release its latest Ocean State Report, which includes nearly 30 updates, including many that will feed into models that will help scientists better understand the forces that drive our climate.

For those involved in the blue economy it is a vital data set which draws on the Copernicus Marine Ocean Monitoring Indicator (OMI) framework to provide information that can be used for a wide range of industries, from fishing to wind energy.

Trillion-dollar market

Billions of people depend on the ocean for their livelihoods, food and energy, and the market value of marine and coastal resources and industries is estimated to be trillions of US dollars. This report helps those with an interest in these industries to optimise operations and improve sustainability.

“The Ocean is a central component of the Earth climate system and human communities depend heavily upon the goods and services provided by the Ocean,” said Karina von Schuckmann, oceanographer and chair of the Copernicus Marine Ocean State Report. “Understanding and monitoring the Ocean based on best available science is crucial to inform society, economic and environmental stakeholders – and to take action to protect the ocean.”

Report shows pace of change

There are, of course, worrying headline issues – and some are getting worse.

The report makes for uncomfortable reading in some key areas, stating: “There continues to be unprecedented warming of the ocean surface, and the past four years are the four warmest since records began.”

Since 1993, global mean sea level has risen at a rate of 3.3mm per year and this rate is accelerating.  Global sea surface temperature has increased at a rate of 0.014 °C per year with warming occurring over most of the globe, particularly in the upper ocean. The 2018 Arctic maximum winter sea ice extent was the second lowest on record after winter 2017.  Oceans are also becoming more acidic.

Global heat content – how much heat energy is stored in the ocean – is becoming more pronounced and is particularly worrying as “a key factor in the Earth's energy budget, ocean-atmosphere interactions, marine ecosystems, and sea level change”.

Helping improve sustainability

It’s not all about the big picture, or about worrying statistics – far from it.

Summer 2020 saw a release of data that will help users better understand cod stocks in the Baltic Sea. By drawing on indicators for a wide range of variables, from fauna above phytoplankton and zooplankton in marine food webs, or volumes of water that host suitable conditions for the cod in terms of levels of salinity, oxygen content and temperature, fisheries will be able to improve their day-to-day activities in order to provide favourable habitats for the fish – and improve sustainability.

The report also explores explore ocean surface transient winds and upwelling, partly a wind-driven mechanism, that produces fertile marine environments and can contribute to carbon sequestration through the biological carbon pump. It’s an important part of the global carbon cycle.

This is important to our understanding of climate change as earlier this year scientists from the Woods Hole Oceanographic Institute showed that the efficiency of the ocean’s biological carbon pump has previously been drastically underestimated, with researchers finding about twice as much carbon sinks into the ocean per year than previously estimated.

This has clear implications for future climate assessments and helps with understanding of the role of the ocean in regulating the climate.

With the US National Snow & Ice Data Center, which is supported by NASA, recently releasing preliminary data showing that Arctic sea ice reached its annual minimum extent of 3.74 million sq km in September 2020, the second lowest in its 42-year-old satellite record, it’s never been more important for scientists to have accurate data on what is becoming an accelerating picture of change.   

About the report:

The Copernicus Ocean State Report is written by more than 140 scientific experts from more than 30 European institutions. This fourth issue highlights how trends in our oceans will impact us all, including warming sea temperatures, rising sea levels, acidification, retreating sea ice, changes in oceanic food webs and extreme weather events. For oceanographers and all those with an interest in ocean governance, this report should be considered essential reading.

The final State of the Ocean report is being published in the IMarEST Journal of Operational Oceanography.

Read the Copernicus Ocean State Report summary here.

Watch a video of the report summary on YouTube.

Amy McLellan is a journalist and author and former editor of Energy Day.