The report has revealed today that scientists from the Massachusetts Institute of Technology (MIT) and Caltech have developed a highly detailed 3D atlas of areas of the Pacific Ocean that contain very little oxygen, named such zones oxygen-hungry zones (ODZ).
The Massachusetts Institute of Technology news reported that the maps depict the volume, depth, and extent of two oxygen-depleted bodies of water in the tropical Pacific Ocean. The study drew on data that had been gathered for more than four decades.
The data was then placed via a computer program, which allowed scientists to produce maps of oxygen deprivation zones at various depths.
The overall levels of oxygen in the ocean have decreased by 2% in the last 70 years, while the number of so-called “dead zones” (regions of the ocean wholly devoid of oxygen) has quadrupled. And while there are some places of the ocean where oxygen levels naturally drop as light fades and oxygen-generating photosynthesis declines (“oxygen minimum zones”), human activity is causing new oxygen-depleted areas to emerge.
The rise of “oxygen-deficient zones” is mostly due to a combination of climate change-induced ocean warming and coastal pollution (ODZs) as the temperature of the atmosphere and water rises, the ocean’s ability to store gas molecules decreases, lowering overall oxygen levels in the ocean.
Algal blooms are also caused by pollution from fertilizer and sewage (both of which contain phosphorus and nitrogen, which are found in limited quantities in the ocean). These algae have a short life span, and the microorganisms that degrade them absorb oxygen, causing further loss. As a result, knowing the size of these ODZs becomes increasingly important as climate change develops.
The researchers were able to construct a 3D map of oxygen levels (Oxygen-Deficient Zones) in the Pacific Ocean off the western shores of North, Central, and South America using 15 million data taken via electrical sensors aboard ships and autonomous robots over the previous 30 years. They eventually discovered two significant ODZs.
The smaller one is about 600,00 cubic kilometers in size and can be found off the coastlines of Ecuador, Peru, and northern Chile (the equivalent of 240 billion Olympic-sized swimming pools). The largest one, which stretches from the Gulf of California to Panama, is roughly three times the size of the first.
Speaking about the new innovation Jarek Kwiecinski, the lead author, said:
“It’s broadly expected that the oceans will lose oxygen as the climate gets warmer. But the situation is more complicated in the tropics where there are large oxygen-deficient zones,”
“It’s important to create a detailed map of these zones so we have a point of comparison for future change.” he maintained.