For the first time in thirty years of monitoring, the Deep Western Boundary Current (DWBC) in the South Atlantic, a key part of the Atlantic Meridional Overturning Circulation (AMOC), reversed from northward to southward in several consecutive months, a frightening development.
Over the period 2004 to 2012, experts observed a slowing down in the circulation circle of AMOC to the tune of seven percent per year, with findings also showing that it weakened over the past century, and speculating that it could weaken even further or come to a halt entirely by 2050.
Meanwhile, the upper-ocean circulation of the equatorial Pacific ocean has been showing significant changes over the past three decades, with strong winds accelerating westward near-surface currents by approximately 20 percent in the central equatorial Pacific, while poleward currents north and south of the equator have also accelerated, increasing by 60 percent and 20 percent respectively.
The situation with the Deep Western Boundary Current, the Atlantic Meridional Overturning Circulation, and the equatorial Pacific region shows changes in relation to ocean currents, with dangerous repercussions staring at the globe, the developments possibly fuelling the release of increased quantity of carbon dioxide to the atmosphere, transformation of global climate patterns, and disruption to life as we know it.
Since the late 1990s, the human-induced weakening of the Antarctic Bottom Water, which usually involves the sinking of 250 trillion tons of nutrient-rich water per year, has been taking place, caused by the dilution of salty bodies close to Antarctica by freshwater from melting icecaps, with the circulation system now showing a decline to the tune of 30 percent.
The AMOC showed consistency from 1955 to 1994, according to experts, but it showed down in the past 20 years, due to human-induced warming of the surface of the ocean and the constant transformations in the amount of salt in the upper layers of the Atlantic near the north pole.
In the equatorial Pacific region, the velocity of wind increased by 20 percent, with equatorial upwelling taking place ten times faster than thought, experts postulating that human-induced global warming could be speeding up currents in this part of the world.
The warming of oceans through climate change, the dilution of salt masses at the poles, and the acceleration of winds in the Pacific lies behind the changing nature of ocean currents, slowing down at some parts of the world, increasing wind speed at other places, and creating freshwater through melting ice caps.
In essence, the consequences of human activities in the south Atlantic has been devastating, bringing about a shift in westerly winds and changes in the Atlantic Circumpolar Current, causing intensified ice melt in the Antarctic, allowing it to lose ice mass at an average rate of about 150 billion tons per year, impacting negatively through massive freshwater dilution.
The consequences of human activities in the north Atlantic has also been devastating, causing melting ice caps, with the Greenland ice sheets becoming the greatest contributor of sea level rise, disappearing four times faster than in 2003, contributing around 20 percent to current sea level rise, leading to increased freshwater input into the North Atlantic, reducing the density and salinity of surface water, weakening the sinking process that drives AMOC.
The consequences of human activities in the equatorial Pacific have been grave, impacting negatively on the wind pattern and ocean temperature, making the boundaries between warm surface water and cooler deeper water to be steeper, causing chaos all over the place.
Human activities are to blame for the situation with ocean currents through climate change, overfishing, and plastic pollution, resulting in the reversal of ocean currents, slowing of natural processes, sea level rise, melting ice caps, and changing wind patterns.
Climate change mitigation, continuous monitoring, ocean conservation, and international cooperation could ensure a sustainable management of ocean currents to prevent human-induced disaster in relation to ocean currents in the near future.
What To Eat
Vegan food food from Antarctica, Credit, Quark Expeditions