Icebergs, Ecologically Speaking “On Fire”

Combine the words iceberg and global warming together and what comes to mind? Probably an image of ice sheets falling down and the apocalypse! But what if I were to say that a new study carried out in the Southern Ocean by leading US scientists has found icebergs to be “ecological hotspots” that enable the surrounding waters to absorb an increased volume of carbon dioxide?

The findings published in the online journal Science Express, state that minerals released from the melting ice triggered blooms of CO2-absorbing phytoplankton (microscopic plants). Shrimp-like organisms called Krill then ate the phytoplankton and the waste material containing the carbon sank to the ocean floor.

How does this link to Global Warming?

According to the BBC…

The number of icebergs found in waters around Antarctica had increased in recent decades as a result of global warming, the researchers wrote in the paper.

“We got a satellite image that covered roughly 11,000 sq km (4,200 sq miles), and counted the number of icebergs within that area,” explained Ken Smith, an oceanographer from Monterey Bay Aquarium Research Institute, California.

We are going to go back and look at smaller icebergs to see how important they are

Dr Ken Smith
Oceanographer
“We had almost 1,000 icebergs.”

The team focused its attention on two icebergs, one measuring 2km by 0.5km (1.2 miles by 0.3 miles) and another 21km in length and 5km wide (13 miles by 3 miles).

Using instruments that included a trawl net and a remotely operated vehicle (ROV) with a video camera, the researchers sampled waters from the ice blocks up to 9km away (5.5 miles).

They found a “substantial enrichment” of minerals, phytoplankton, krill and seabirds in the surrounding water up to 3.7km away (2.3 miles) compared with areas with no icebergs.

“These results suggest that free-drifting icebergs can substantially impact the (open sea) ecosystem of the Southern Ocean and can serve as areas of enhanced production and sequestration of organic carbon to the deep sea,” the scientists wrote.

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