Initialized near-term regional climate change prediction

Abstract

Climate models are seen by many to be unverifiable. However, near-term climate predictions up to 10 years into the future carried out recently with these models can be rigorously verified against observations. Near-term climate prediction is a new information tool for the climate adaptation and service communities, which often make decisions on near-term time scales, and for which the most basic information is unfortunately very scarce. The Fifth Coupled Model Intercomparison Project set of co-ordinated climate-model experiments includes a set of near-term predictions in which several modelling groups participated and whose forecast quality we illustrate here. We show that climate forecast systems have skill in predicting the Earth's temperature at regional scales over the past 50 years and illustrate the trustworthiness of their predictions. Most of the skill can be attributed to changes in atmospheric composition, but also partly to the initialization of the predictions.

Climate model simulations of the observed early-2000s hiatus of global warming

“…A similar loss of skill for those same years is also seen in the Atlantic (Supplementary Fig. 3), although the overall skill levels in the Atlantic are higher than in the Pacific 33,34 (for example, 20 hindcast periods have anomaly pattern correlation values above +0.8 for the Atlantic in Supplementary Fig. 3, whereas there are only 5 in the Pacific in Fig.…”

“…The lack of skill for the six initial years 1986-1991, out of the 46 possible initial years in the hindcast period, probably contributes to the lower overall skill for some areas of the Pacific region for the entire hindcast period from 1960 to 2005 for grid-point time series correlations 1,33,34 . Reasons for this drop in skill for those initial years are at present under investigation.…”

Impact of observed North Atlantic multidecadal variations to European summer climate: a linear baroclinic response to surface heating

“…The North Atlantic has been shown to be a key region for the prediction of climate on decadal time scales. Robust prediction skill has been established for various parameters, such as temperature and heat content (Pohlmann et al 2009;Kröger et al 2012;Doblas-Reyes et al 2013). Prediction skill is further assessed for climate impacts, such as for the multidecadal variability of Atlantic tropical cyclones, which have been considered to origin from the subpolar gyre region (Smith et al 2010;Dunstone et al 2011), or the European summer climate Hermanson et al 2014;Sienz et al 2016).…”

Recent advances in understanding the Arctic climate system state and change from a sea ice perspective: a review

“…SPECS and the CMIP6 decadal prediction experiments) promise rapid knowledge gains on the real-world potential. Current retro-active prediction experiments provide good predictability for the Arctic area (Doblas-Reyes, 2013) On the down side for predictability prospects is the thinning of the sea ice, which possibly reduces predictability due to lower signal storage capacity in the ice and increased interannual variability. It is unknown to what extent this can be compensated by heat anomalies stored in the ocean.…”