Human shadow cast over Caribbean slows coral growth
April 15, 2013
Striking Caribbean sunsets occur when particles in the air scatter incoming sunlight. But a particulate shadow over the sea may also have underwater effects
Striking Caribbean sunsets occur when particles in the air scatter incoming sunlight. But a particulate shadow over the sea may also have underwater effects. Researchers including STRI's Héctor Guzmán, linked airborne particles caused by volcanic activity and air pollution to episodes of slow coral reef growth recorded in coral reef cores.
Like tree rings, long-lived coral skeletons preserve a record of coral expansion. With researchers from the University of Queensland, the Australian Nuclear Science and Technology Organization and STRI, Lester Kwiatkowski, University of Exeter, analyzed coral cores drilled in reefs near the Atlantic entrance of the Panama Canal formed by the coral species Siderastrea siderea between 1880 and 1989 and cores from the Turneffe atoll in Belize formed by Montastrea faveolata between 1905 and 1998. An Earth-system model simulation told them how well sea-surface temperature, short-wave radiation and aragonite-saturation state -a measure of ocean acidification- predicted changes in coral growth.
"Our study suggests that coral ecosystems are likely to be sensitive to not only future global atmospheric carbon dioxide concentration but also to regional aerosol emissions associated with industrialization and decarbonization," said Kwiatkowski.
"The coral growth chronology for Panama allowed us to identify the effects of human interventions at the beginning of 1900s," said Guzmán, "but the decline in growth observed by the middle of the 20th century corresponding to the beginnings of the industrial era in coastal Panama remained unresolved by the model."
Reference: Kwiatkowski, L., Cox, P.M., Economou, T., Halloran, P.R., Mumby, P.J., Booth, B.B.B., Carilli, J. and Guzman, H.M. 2013. Caribbean coral growth influenced by anthropogenic aerosol emissions. Nature Geoscience. doi:10.1038/ngeo1780 published online 7 April, 2013