An increase in the average temperature of a large patch of ocean in the Pacific region is baffling scientists across the world. The patch is located near the sparsely populated Chatham Islands, about 800 Kilometers East of New Zealand’s South Island.
The patch is massive in size, almost 1.5 times that of Texas and can be spotted on oceanic thermal images as a giant blob of red. According to James Renwick, a scientist at Victoria University in Wellington, New Zealand, “surface temperatures in that part of the Pacific hover around 15 degrees Celsius, but the blobs is around 20 degrees”.
In his opinion it the biggest patch of above-average warming on the planet right now. A similar blob of heated ocean had devastated marine life and coral along the Pacific Northwest back in 2014. Scientists worry about how the new blob will impact marine life near the New Zealand coast.
Many scientists attribute the formation of the high-temperature blob to a phenomenon called Anti-cyclone. Anti-cyclones are high-pressure weather systems in which the atmosphere and surrounding air become heavy, stifling nearby winds and causing calm, stagnant conditions.
In this case, the warmed up ocean region isn’t getting sufficient winds to cool itself off. While this is a natural phenomenon and New Zealand has seen average oceanic temperature increases of around 1 or 2 degrees Celcius, an increase of this magnitude (6C) is completely new.
Some scientists say this has got nothing to do with Global warming. But others say Global warming can make these marine heatwaves much more intense. It is to be noted that ocean absorbs 93 percent of the extra heat trapped on Earth by the greenhouse gases.
The added heat plus the presence of natural anti-cyclones trigger heat blobs with even higher average temperatures.
Even slightest increase in oceanic temperatures can completely disrupt marine life. A prime example of this is the heat blob of 2014 that hit the Pacific region between the coasts of Hawaii, Alaska, and California. It resulted in large scale deaths of seal and sea-bird populations, algal bloom spread, and coral bleaching.
Now, the same threat is looming over the coastal lines of New Zealand too. Scientists will be studying the temperature spike for the coming weeks to gain more insight into the phenomenon and possibly identify its cause and local impact.