Emergence of multiple ocean ecosystem drivers in a large ensemble suite with an Earth system model ...

• Main Authors: Rodgers, Keith B., Lin, J., Frölicher, Thomas L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2015
• Subjects: Ocean acidification
• Online Access: https://dx.doi.org/10.3929/ethz-b-000101963; http://hdl.handle.net/20.500.11850/101963

Marine ecosystems are increasingly stressed by human-induced changes. Marine ecosystem drivers that contribute to stressing ecosystems – including warming, acidification, deoxygenation and perturbations to biological productivity – can co-occur in space and time, but detecting their trends is complicated by the presence of noise associated with natural variability in the climate system. Here we use large initial-condition ensemble simulations with an Earth system model under a historical/RCP8.5 (representative concentration pathway 8.5) scenario over 1950–2100 to consider emergence characteristics for the four individual and combined drivers. Using a 1-standard-deviation (67% confidence) threshold of signal to noise to define emergence with a 30-year trend window, we show that ocean acidification emerges much earlier than other drivers, namely during the 20th century over most of the global ocean. For biological productivity, the anthropogenic signal does not emerge from the noise over most of the global ... : Biogeosciences, 12 (11) ...