Researchers suggest that whales help cool the Earth by taking carbon dioxide out of the atmosphere.
No one likes the sight of beached whales. Seeing the largest animals helpless on land is always a thought-provoking scenario. Many grow curious since whales aren't often an easy sight to see. What people don't often realize is that, other than the loss of the life of a majestic creature, the opportunity for carbon sequestration was also lost.
How Whales Remove CO2 from the Atmosphere
Whales, especially the endangered baleen and sperm whales, are some of the largest creatures on the planet. Their enormous bodies store carbon dioxide and their presence in the ocean molds the ecosystems around them.
From the depths of the ocean where they roam, whales help determine the planet's temperature -- a fact which has only recently been appreciated by the scientific community.
In a research article published on Plos One in 2010, researchers say, "On land, humans directly influence the carbon stored in terrestrial ecosystems, but in the open ocean, the carbon cycle is assumed to be free of direct human influences."
However, this assumption neglects the surprising major impact of whaling.
For centuries humans have hunted and killed whales for their whalebone, oil, and meat. The earliest records of commercial whaling date back to 1,000 CE. Since then, millions of whales have been killed. Experts believe that the whale population declined between 66% to 90%.
When whales die, their bodies sink down to the ocean floor--all the carbon dioxide stored in their bodies is transferred from the surface to the deep sea where it shall remain for centuries.
In the 2010 study, researchers found that prior to commercial whaling, the populations of whales would have sunk 190,000 to 1.9 million tonnes of carbon dioxide per year. However, carcasses were prevented to sink to the seabed. Instead, whale bodies were processed that resulted in the release of carbon dioxide into the atmosphere.
Andrew Pershing, an author of the study and marine scientists from the University of Maine, estimates that 20th-century commercial whaling has added 70 million tonnes of CO2 into the atmosphere. He says, "This is a lot, but 15 million cars do this in a single year. The US currently has 236 million cars"
Whales are not only valuable in death. The excrements of these large mammals are surprisingly relevant to the climate.
Whales feed in the depths of the ocean, and breach surface waters to breathe and excrete. The iron-rich feces create conducive conditions for phytoplankton growth. Despite the microscopic size of these creatures, together, phytoplankton influence the planet's atmosphere by capturing roughly 40% of all carbon dioxide produced--which is 4 times the amount captured by the Amazon rainforest.
Vicki Hames, policy manager at the Whale and Dolphin Conservation says in an article from BBC, "We need to think of whaling as a tragedy that has removed a huge organic carbon pump from the ocean that could have been a much larger multiplying effect on phytoplankton productivity and the ocean's ability to absorb CO2."
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