Projects per year
Despite the observed monotonic increase in greenhouse-gas concentrations, global mean temperature displays important decadal fluctuations typically attributed to both external forcing and internal variability. Here, we provide a robust quantification of the relative contributions of anthropogenic, natural, and internally-driven decadal variability of global mean sea surface temperature (GMSST) by using a unique dataset consisting of 30-member large initial-condition ensembles with five Earth System Models (ESM-LE). We present evidence that a large fraction (~29–53%) of the simulated decadal-scale variance in individual timeseries of GMSST over 1950–2010 is externally forced and largely linked to the representation of volcanic aerosols. Comparison with the future (2010–2070) period suggests that external forcing provides a source of additional decadal-scale variability in the historical period. Given the unpredictable nature of future volcanic aerosol forcing, it is suggested that a large portion of decadal GMSST variability might not be predictable.
- 1 Active
Pitman, A. J., Jakob, C., Alexander, L., Reeder, M., Roderick, M., England, M. H., Abramowitz, G., Abram, N., Arblaster, J., Bindoff, N. L., Dommenget, D., Evans, J. P., Hogg, A. M., Holbrook, N. J., Karoly, D. J., Lane, T., Sherwood, S. C., Strutton, P., Ebert, E., Hendon, H., Hirst, A. C., Marsland, S., Matear, R., Protat, A., Wang, Y., Wheeler, M. C., Best, M. J., Brody, S., Grabowski, W., Griffies, S., Gruber, N., Gupta, H., Hallberg, R., Hohenegger, C., Knutti, R., Meehl, G. A., Milton, S., de Noblet-Ducoudre, N., Or, D., Petch, J., Peters-Lidard, C., Overpeck, J., Russell, J., Santanello, J., Seneviratne, S. I., Stephens, G., Stevens, B. & Stott, P. A.
Monash University – Internal University Contribution, Monash University – Internal School Contribution, Monash University – Internal Faculty Contribution, University of New South Wales, Australian National University , University of Melbourne, University of Tasmania, Bureau of Meteorology (BOM) (Australia), Department of Planning, Industry and Environment (DPIE) (New South Wales)
1/01/17 → 3/08/24