Humans are damaging the world's oceans, say scientists

Washington, July 30 (ANI): In a new study, scientists have said that there is mounting evidence that human activity is changing the world's oceans in profound and damaging ways.

The study was carried out by Professor Mike Kingsford of the ARC Centre of Excellence for Coral Reef Studies and James Cook University and colleague Dr Andrew Brierley of St Andrews University, Scotland.

It warns that Man-made carbon emissions "are affecting marine biological processes from genes to ecosystems over scales from rock pools to ocean basins, impacting ecosystem services and threatening human food security."

According to the study, rates of physical change in the oceans are unprecedented in some cases, and change in ocean life is likely to be equally quick.

These include changes in the areas fish and other sea species can inhabit, invasions, extinctions and major shifts in marine ecosystems.

"In the past, the boundaries between geological ages are marked by sudden losses of species. We may now be entering a new age in which climate change and other human-caused factors such as fishing are the major threats for the oceans and their life," said Andrew and Mike.

"Given how essential the oceans are to how our entire planet functions, it is vital that we intervene before more tipping points are passed and the oceans go down the sort of spiral of decline we have seen in the world's tropical forests and rangelands, for example," they added.

Man-made carbon emissions are now above the 'worst case' scenario envisioned by the Intergovernmental Panel on Climate Change (IPCC), causing the most rapid global warming seen since the peak of the last Ice Age.

At the same time the carbon is acidifying the oceans, with harmful consequences for certain plankton and shellfish.

"At current emission rates, it is possible we will pass the critical level of 450 parts per million CO2 in the atmosphere by 2040. That's the level when, it is generally agreed, global climate change may become catastrophic and irreversible," according to Andrew and Mike.

"At that point, we can expect to see the loss of most of our coral reefs and the arctic seas," they added.

Besides the changes induced by carbon emissions, the oceans are also under assault from over-fishing, increased UV exposure, toxic pollution, alien species and disease.

The combined effect is to weaken the ability of many species to withstand these multiple stresses.

According to Mike, "On a global scale, an immediate reduction in CO2 emissions is essential to minimize future human-induced climate change." (ANI)