Science & Tech

Our beloved blue oceans are turning ominously green

Our beloved blue oceans are turning ominously green
Non-profit 'Healthy Seas' cleans up contaminated Greek oceans
Euronews News / VideoElephant

The Earth’s blue oceans are turning ominously green and it’s all an indication of the health of the ecosystem.

Our oceans cover more than 70 per cent of planet Earth and the ecosystem is home to an untold number of unidentified sea creatures and structures that have left scientists baffled.

Of course, pictures from space show our oceans are blue, but experts are now noticing that the colour of the seas is starting to turn green.

A new study led from the National Oceanography Centre in the UK examined 20 year’s worth of data from the MODIS instrument onboard NASA’s Aqua satellite.

The results were damning, showing that 56 per cent of the world’s sea surface has noticeably undergone an alteration in colour by turning greener.


While the change is barely perceptible to the human eye, experts warn it is indicative of the ocean’s worsening health and composition.

The most pronounced areas of colour change could be observed in tropical and subtropical regions. Experts believe this could be down to changes in levels of phytoplankton – a microscopic organism that plays a vital role in the carbon cycle.

Over data spanning decades, the MODIS instrument was able to analyse the spectrum of light that reflects off the surface of the ocean, giving experts an insight into changes that other measurements might not have detected, such as chlorophyll measurements.

The study suggested that increased ocean stratification due to climate change could be a main cause. This occurs as the surface warms and becomes less likely to mix with colder, nutrient-rich layers of water – the result creates conditions that are more suitable for certain types of plankton.

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