HR: 11:50h
AN: GC22A-07    [Abstracts]
TI: Dynamical consistent behaviour across spatial scales in large-ensemble climate experiments
AU: * Cuellar, M C
EM: mcuellar@ouce.ox.ac.uk
AF: Tyndall Centre for Climate Change Research., OUCE. University of Oxford, Oxford, OX1 3QY, United Kingdom
AU: Lopez, A
EM: alopez@ouce.ox.ac.uk
AF: Tyndall Centre for Climate Change Research., OUCE. University of Oxford, Oxford, OX1 3QY, United Kingdom
AU: New, M
EM: mnew@ouce.ox.ac.uk
AF: Tyndall Centre for Climate Change Research., OUCE. University of Oxford, Oxford, OX1 3QY, United Kingdom
AB: The use of Global Climate Model (GCM) simulations of climate systems in the assessment of potential impacts of future climate change is limited to the ability of the GCMs to simulate the climate and the presence of diverse uncertainty sources. A perturbed physics ensemble consists of a large number of model runs obtained by varying the GCM physical parameters within their physically acceptable range. Such an ensemble is specifically designed to sample climate-model uncertainty and provides a new ground to explore the possible range of future plausible climates. We present a methodology that looks for an optimal forecast combination of model runs. Such combination is optimal in the sense that if use to forecast then it will perform better than a forecast based only on historical records i.e. the climatology. In particular, we explore the Ignorance skill score. This score measures the amount of information produced when a forecast is performed using a combination of models compared to climatology. At the same time, assessment of the predictability of the resulting combinations is sought in a similar way as for medium-range/seasonal weather model-based forecasting. We compare global and regional results for the Global Mean Temperature (GMT), as a test case in a theoretical framework, using data sets of runs of the climateprediction.net; the largest perturbed physics climate model ensemble available up to date.
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1620 Climate dynamics (0429, 3309)
DE: 1626 Global climate models (3337, 4928)
DE: 1630 Impacts of global change (1225)
DE: 1637 Regional climate change
SC: Global Climate Change [GC]
MN: 2007 Joint Assembly