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1 March 2017

Study Warns of Famine & Mass-Extinction due to Rising Ocean Temperatures

According to an alarming new study published in the journal Elementa, the cumulative effects of climate change are expected to halve the amount of food reaching marine life on the sea floor, resulting in a drastic transformation of global ecosystems and the extinction of many larger animals.

The study identified 3 major factors that may lead to mass-extinctions across 31 Earth modelling systems, making use of data and models developed for the Intergovernmental Panel on Climate Change (IPCC); it warns of the potentially devastating effects of increasing ocean temperatures, ocean deoxygenation and acidification leading to a massive reduction in food reaching the sea floor.

Img: Cengage Learning
Worst affected will be the bathyal zone - the waters sitting 200-3000m below the surface - where temperatures are expected to rise by as much as 4°C in the Pacific, Atlantic and Arctic oceans. Meanwhile the abyssal zone, situated lower than the bathyal at depths of 3000-6000m, is expected to warm by 0.5-1°C in the North Atlantic, Southern and Arctic oceans.

“That is a massive temperature change in these environments,” said study author Andrew Thurber of Oregon State University in the US, “It is the equivalent of having summer for the first time in thousands to millions of years.

“Biodiversity in many of these areas is defined by the meagre amount of food reaching the seafloor and over the next 80-plus years – in certain parts of the world – that amount of food will be cut in half,

“Some species will thrive, some will migrate to other areas, and many will die. Parts of the world will likely have more jellyfish and squid, for example, and fewer fish and cold water corals.”

However, the damage is unlikely to be confined to deep ocean regions, as changes to one ecosystem often have knock-on effects on many others. What will initially begin in the depths will soon reach the surface as overall temperatures increase and currents carry deoxygenated waters to the surface. These waters can cause serious damage, leading to the deaths of masses of sea creatures when they reach the coast. This, in turn, will be felt by the fishing industry as populations dwindle.

“A decade ago, we even saw low-oxygen water come shallow enough to kill vast numbers of Dungeness crabs,” said Thurber, “The die-off was massive.”

Andrew Sweetman, of the Lyell Centre for Earth and Marine Science and Technology at Heriot-Watt University in Edinburgh, also took time to warn not only of the potential for damage caused by rising temperatures and other factors associated with global warming, but also additional pressures caused by human activity.

“Pressure from fishing has led to many deep-sea fish species being severely exploited through trawling and longlining, with some species having been fished to commercial extinction,” said Sweetman.

“Politicians the world over must recognise the vulnerability of life on the ocean floor to climate-related stressors, and the direct influence that the surface climate can exert on the world's largest ecosystem.”

Sam Bonson

Sam is an aspiring novelist with a passion for fantasy and crime thrillers. He is currently working as a content writer, journalist & editor in an attempt to expand his horizons.