For the first time a study published on Nature Climate Change has included the damage caused by climate change to the oceans in the calculation of the social cost of carbon, a monetary measure of the long-term consequences of CO2 emissions. Taking into account this new value, baptized blue social cost of carbon, the global social weight of CO2 emissions has almost doubled: «This study is the first to attribute equivalent economic values in monetary terms to these hitherto neglected oceanic impacts», underlines Bernardo Bastien-Olvera, coordinator of the research.
What was considered. The CO2 emitted into the atmosphere by human activities damages the oceans by heating them, altering their chemistry, reducing their ability to retain the oxygen necessary for the survival of marine species, as well as increasing extreme climate events.
All this not only damages coral reefs and coastal infrastructure, but has strong impacts on fishing activities, on the nutritional values of fish products and consequently on people’s health, as well as on other intangible values such as the benefits that we humans derive from enjoying ecosystems and biodiversity.
Doubled cost. In their analysis the authors took all these variables into account, thus arriving at calculating the blue social cost of carbon. If without this value CO2 emissions “cost” us 51 dollars per ton, calculating the consequences on the oceans the figure rises by 91% and reaches 97.2 dollars per ton. “If we do not assign an economic value to the damage that climate change causes to the oceans, it will remain invisible to major policy makers,” Bastien-Olvera underlines.
A cost that is not the same for everyone. The study also highlights that not everyone in the world suffers the consequences of damage to the oceans in the same way: islands and small economies are the most affected, because the inhabitants feed mainly on fish products and are most affected by the reduction of nutrients linked to the increase in ocean temperatures.
Including the oceans in the calculation of the social cost of carbon therefore means making visible a previously ignored part of the price we pay for CO2 emissions, providing political parties with an additional tool to adopt increasingly effective and fair laws.
