Whales as a Form of Climate Mitigation

By Suzanna Schofield

As climate change continues, we need to be looking at nature-based solutions. One solution is the conservation of whales.

Climate change and increased extreme weather events

2024 was the warmest year on record globally. It was the first year that the average global temperature exceeded 1.5 degrees Celsius above its pre-industrial level. These temperatures have devastating effects. There were many extreme weather events and natural disasters contributing to climate change this past year that killed thousands of people:

●       Super Typhoon Yagi hit several countries in Asia resulting in floods and landslides. It was the strongest typhoon in 70 years to hit Vietnam. Thousands of homes were destroyed, and hundreds of people were killed.

●       Hurricane Helene in the United States hit Florida and caused severe flooding in North Carolina and East Tennessee. It killed more than 230 people and caused damage costing as high as $200 billion.

●       Cyclone Remal struck West Bengal, India, and Bangladesh causing the evacuation of over 807,000 people in Bangladesh. The cyclone caused over 197 thousand acres of farmland flooding which led to major disruptions to local food systems.

●       Cyclone Chido hit Mayotte, Mozambique, Malawi, and Zimbabwe. Over 300 thousand people were impacted in northern Mozambique. The extreme flooding also destroyed thousands of hectares of crops leading to food shortages within the region.

●       Chile had wildfires that burned almost 160 thousand acres due to days of scorching heat. These fires caused more damage than any natural disaster in Chile since 2010.

●      Over 5,000 wildfires in Canada burned 13.29 million acres in 2024. The worsened air quality resulting from these fires led to increased risks for folks with respiratory issues across Canada and the United States.

And, while these extreme weather events increase in intensity and frequency, and more and more people face the consequences, U.S. greenhouse gas emissions levels are estimated to rise up to 36% higher than current policy by 2035 due to policy changes leading to greater dependence on oil and gas.

So, what can we do to curb the impacts of climate change? One mitigation measure is nature-based solutions.

Nature-based solutions

According to the International Union for Conservation of Nature and Natural Resources (IUCN), nature-based solutions are “actions to address societal challenges through the protection, sustainable management and restoration of ecosystems, benefitting both biodiversity and human well-being.”

Natural climate solutions can provide 37% of cost-effective carbon dioxide mitigation needs to limit global warming. Some of these solutions include actions like conserving mangroves, forest landscape restoration, but one that is often overlooked is the conservation of whales.

How do whales act as a climate solution?

Whales act as carbon sinks. Carbon sinks include anything that absorbs more carbon dioxide from the atmosphere than it releases. Think about something like trees.

Whales absorb more carbon than they release. As ecosystem engineers, whales dive to ocean depths to feed on krill, fish, or marine mammals depending on the species. After feeding, whales come back to the ocean’s surface. They release enormous fecal plumes. These plumes are rich in iron and nitrogen which are both considered limiting nutrients that the ocean ecosystem depends on. Phytoplankton growth is stimulated as a result, leading to greater rates in photosynthesis which pulls carbon dioxide out of the atmosphere.

Nutrient cycling also occurs across oceans. Baleen whales migrate from highly productive, high-latitude feeding and low-latitude calving grounds. During the winter months when the whales are in the warmer waters of the calving grounds, they fast. For example, humpback whales will migrate from Alaska to Hawai’i. So, they move the nutrients from the waters of Alaska to the waters of Hawai’i, again contributing to increases in phytoplankton and photosynthesis.

Whales also act as forms of carbon sinks themselves. When whales die, they sink to the ocean floor. Each great whale (which includes the species blue, bowhead, sperm, southern right, North Pacific right, North Atlantic right, sei, Bryde’s, Omura’s, fin, grey, and humpback) sequesters 33 tons of carbon dioxide on average, or 66,000 pounds. When their bodies sink to the ocean floor, they take those 66,000 pounds of carbon out of the atmosphere for centuries, along with feeding the species that call the ocean depths their home. Scientists found that before industrial whaling, populations of whales would have sunk between 190,000 to 1.9 million tonnes of carbon per year which is the equivalent of taking between 40,000 and 410,000 cars off the road each year.

In comparison, an oak tree can only store as high as 48 pounds of carbon dioxide every year, or 14,400 pounds of carbon dioxide in its lifetime.

However, this impact and climate mitigation measure is limited. Whale populations have significantly declined since the 1700s.

What’s happening to whales?

Whales were killed at large rates for the oil in their bodies, mostly in their blubber, from the 16th century to the 19th century. This oil was used for lighting and lubrication for the gears of the industrial revolution. This demand for whale oil was replaced with petroleum oil products.

Whales were also killed during World War II when whale oil was important to the fat rations of Europe.

As whales have low reproductive rates, these whaling efforts devastated their populations. For example, pre-whaling blue whale populations had about 350,000 individuals. Today, there are about 5,000-10,000 blue whales in the Southern Hemisphere and about 3,000-4,000 in the Northern Hemisphere.

When the whale populations were decimated, whaling efforts began declining. By the 1980s, the international whale trade was dead, though there were some countries that did not follow suit with the rest of the world. Those countries still continue to have a whaling industry.

In 1946, the International Whaling Commission (IWC) was established to conserve whale stocks. Initially, it prohibited the killing of right and gray whales and limited the annual Antarctic kill to 15,000 Blue Whale Units. During the 1986-90 whaling season, a moratorium on all commercial whaling was agreed to by members of the IWC. It remains in force, though Japan and Norway both have continued their whaling efforts.

Though commercial whaling has significantly declined, whales are still under threat. Whales are also dying from the effects of climate change, fisheries, pollution, and other human-wildlife conflicts.

Climate change impact on whales

Climate change is causing rising ocean temperatures. This rise leads to changes in plankton levels. Phytoplankton survive better in cooler temperatures. Zooplankton, many of the whale species primary food source, feed on this phytoplankton. When phytoplankton declines, zooplankton declines.

Zooplankton also depend on sea ice coverage as the microalgae that grows in the ice is an important food source for the zooplankton. With sea ice melting, this food source is also declining.

With zooplankton declining, the whale populations also decline.

The population decline is not just happening to baleen whales. Toothed whales are also seeing declines in their food sources as the entire ocean ecosystem is declining in health due to climate change.

Conclusion

We need to protect whales and keep investing and advocating for nature-based solutions that promote sustainable climate mitigation measures.

Works Cited

●      British Antarctic Survey. “Retreating Sea Ice Keeps Zooplankton in the Depths.” British Antarctic Survey, 28 Aug. 2023, https://www.bas.ac.uk/media-post/retreating-sea-ice-keeps-zooplankton-in-the-depths/.

●      Center for Biological Diversity. “Blue Whale.” Center for Biological Diversity, 2023, https://www.biologicaldiversity.org/campaigns/esa_works/profile_pages/BlueWhale.html

●      Chami, Ralph, et al. “Nature’s Solution to Climate Change.” IMF, Dec. 2019, https://www.imf.org/en/Publications/fandd/issues/2019/12/natures-solution-to-climate-change-chami#:~:text=Whales%20accumulate%20carbon%20in%20their,of%20the%20atmosphere%20for%20centuries.

●      ClientEarth Communications. “What Is a Carbon Sink?” ClientEarth, 22 Dec. 2020, https://www.clientearth.org/latest/news/what-is-a-carbon-sink/.

●      Copernicus. “2024 Is the First Year to Exceed 1.5°C above Pre-Industrial Level.” Copernicus, 10 Jan. 2025, https://climate.copernicus.eu/copernicus-2024-first-year-exceed-15degc-above-pre-industrial-level#:~:text=2024%20is%20confirmed%20by%20the,above%20its%20pre%2Dindustrial%20level.

●      European Commission. “Nature-Based Solutions .” Research and Innovation, 2025, https://research-and-innovation.ec.europa.eu/research-area/environment/nature-based-solutions_en.

●      Gibson, Kalina. “The Trump Administration’s Retreat From Global Climate Leadership.” Center for American Progress, 21 Jan. 2025, The Trump Administration’s Retreat From Global Climate Leadership.

●      Griscom, Bronson W., et al. “Natural Climate Solutions.” Proceedings of the National Academy of Sciences, no. 44, Proceedings of the National Academy of Sciences, Oct. 2017, pp. 11645–50. Crossref, doi:10.1073/pnas.1710465114.

●      IUCN. “Ensuring Effective Nature-Based Solutions - Resource | IUCN.” IUCN, 13 Feb. 2024, https://iucn.org/resources/issues-brief/ensuring-effective-nature-based-solutions.

●      Jackson, Gordon. “Whale Oil.” Encyclopædia Britannica, Encyclopædia Britannica, https://www.britannica.com/technology/whale-oil. Accessed 10 Apr. 2025.

●      Kaunana. “New Study Reveals Whales as Marine Ecosystem Engineers.” Kaunana, 7 July 2014, https://manoa.hawaii.edu/kaunana/new-study-reveals-whales-as-marine-ecosystem-engineers/.

●      Kogut, Peter. “Natural Disasters 2024: Chronicle Of Extreme Weather Events.” EOS Data Analytics, EOS Data Analytics, 24 Jan. 2025, https://eos.com/blog/natural-disasters-2024/.

●      National Marine Sanctuary Foundation. “How Does Whale Poop Help Climate Change? .” National Marine Sanctuary Foundation, Dec. 2018, https://marinesanctuary.org/blog/whale-poop-and-climate-change/.

●      NOAA. “Whales and Climate Change: Big Risks to the Ocean’s Biggest Species | NOAA Fisheries.” NOAA, 2022, https://www.fisheries.noaa.gov/national/climate/whales-and-climate-change-big-risks-oceans-biggest-species.

●      NOAA Fisheries. “Humpback Whale .” NOAA, 2025, https://www.fisheries.noaa.gov/species/humpback-whale.

●      Rafferty, John. “Hurricane Helene.” Encyclopædia Britannica, Encyclopædia Britannica, http://www.britannica.com/event/Hurricane-Helene. Accessed 10 Apr. 2025.

●      Whale and Dolphin Conservation. “Climate Change.” Whale and Dolphin Conservation, Whale & Dolphin Conservation UK, 10 Mar. 2025, https://uk.whales.org/our-goals/create-healthy-seas/climate-change/#:~:text=Whales%20play%20a%20key%20part,change%20and%20sustain%20fish%20stocks.

●      Whaling History. “Whaling History.” Whaling History – Connecting All Things Whaling, 2025, https://whalinghistory.org/.

●      Yeo, Sophie. How Whales Help Cool the Earth. BBC, 20 Jan. 2021, https://www.bbc.com/future/article/20210119-why-saving-whales-can-help-fight-climate-change.