Saving the whale is more important than planting trees when it comes to climate change, scientists argue

Whales lock carbon in their bodies and encourage the production of phytoplankton, which produce 50 per cent of the world's oxygen - Getty Images Contributor
Whales lock carbon in their bodies and encourage the production of phytoplankton, which produce 50 per cent of the world's oxygen - Getty Images Contributor

Saving the whale is more important than planting trees to combat climate change, scientists have found, as they capture vast amounts of carbon in their bodies before sinking to the bottom of the ocean.

Environmental scientists have been working against the clock to find the best ways for humans to reduce our carbon footprint by taking measures to allow more greenhouse gases to be absorbed from the atmosphere.

Planting trees has commonly been understood as one of the best ways to save the planet, with all political parties vowing to spend millions of pounds to flood Britain with greenery in their general election pledges.

While trees are important and forests referred to as "the lungs of the Earth", new research from the International Monetary Fund (IMF) has found that one whale is worth more than thousands of trees when it comes to carbon absorption.

Whales are currently under significant man-made threat, including ship strikes, entanglement in fishing nets, waterborne plastic waste, and noise pollution. Their population has been decimated over the last century from 5 million to 1.5 million.

It is thought that without action, it could take more than 30 years to restore their population as they are still under siege from whalers and choking on plastic pollution.

The mammals accumulate carbon in their bodies throughout their long lives, with some species living for up to 90 years, and then when they die they take that carbon to the bottom of the ocean, where it is stored for centuries.

Each whale can lock almost 30,000 kilograms of carbon dioxide on average out of the atmosphere. A tree, meanwhile, absorbs only up to 21 kilograms of  carbon dioxide a year.

As well as this, whales also support the production of phytoplankton, which contributes at least 50 per cent of all oxygen to the Earth’s atmosphere and captures as much carbon dioxide as 1.7 trillion trees, or four Amazon forests.

They do this as when they swim up to the surface from deep waters, their large bodies move nutrients up with them. Bringing nutrients to the surface increases the food source for the tiny but crucial organisms.

Whales bring minerals up to the ocean surface through their vertical movement, called the “whale pump,” and through their migration across oceans, called the “whale conveyor belt".

Increasing phytoplankton productivity by just 1 per cent would have the same effect as the sudden appearance of 2 billion mature trees, according to the study.

Ralph Chami and Sena Oztosun from the IMF’s Institute for Capacity Development, along with professors from Duke University and the University of Notre Dame said increasing whale populations “could lead to a breakthrough in the fight against climate change.”

“Coordinating the economics of whale protection must rise to the top of the global community’s climate agenda,” they wrote.

“Since the role of whales is irreplaceable in mitigating and building resilience to climate change, their survival should be integrated into the objectives of the 190 countries that in 2015 signed the Paris Agreement for combating climate risk.”

The authors put the value of one animal at more than $2 million (£1.54m), taking into account the value of carbon sequestered over the whale’s lifetime as well as other economic contributions such as fishery enhancement and ecotourism.

They recommended that governments compensate those causing the threats to the whale population if they stop doing so, a group that includes countries, businesses, and individuals.