Back to Search
Start Over
A probabilistic calibration of climate sensitivity and terrestrial carbon change in GENIE-1.
- Source :
- Climate Dynamics; Oct2010, Vol. 35 Issue 5, p785-806, 22p, 2 Diagrams, 5 Charts, 7 Graphs
- Publication Year :
- 2010
-
Abstract
- In order to investigate Last Glacial Maximum and future climate, we 'precalibrate' the intermediate complexity model GENIE-1 by applying a rejection sampling approach to deterministic emulations of the model. We develop ~1,000 parameter sets which reproduce the main features of modern climate, but not precise observations. This allows a wide range of large-scale feedback response strengths which generally encompass the range of GCM behaviour. We build a deterministic emulator of climate sensitivity and quantify the contributions of atmospheric (±0.93°C, 1 σ) vegetation (±0.32°C), ocean (±0.24°C) and sea-ice (±0.14°C) parameterisations to the total uncertainty. We then perform an LGM-constrained Bayesian calibration, incorporating data-driven priors and formally accounting for structural error. We estimate climate sensitivity as likely (66% confidence) to lie in the range 2.6-4.4°C, with a peak probability at 3.6°C. We estimate LGM cooling likely to lie in the range 5.3-7.5°C, with a peak probability at 6.2°C. In addition to estimates of global temperature change, we apply our ensembles to derive LGM and 2xCO probability distributions for land carbon storage, Atlantic overturning and sea-ice coverage. Notably, under 2xCO we calculate a probability of 37% that equilibrium terrestrial carbon storage is reduced from modern values, so the land sink has become a net source of atmospheric CO. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 09307575
- Volume :
- 35
- Issue :
- 5
- Database :
- Complementary Index
- Journal :
- Climate Dynamics
- Publication Type :
- Academic Journal
- Accession number :
- 53912836
- Full Text :
- https://doi.org/10.1007/s00382-009-0630-8