Understanding and predicting the state of North Atlantic Oscillation (NAO) is key to forecasting weather in United Kingdom (UK). It has been shown that particular phases Madden–Julian (MJO) act as precursors either NAO+ or NAO? events. We assess ability UK Met Office coupled climate model (HadGEM3-GC3.1-MM) simulate these NAO responses at lead times 1–2 weeks show improvements are needed modell...

To better understand what drives El Niño, an analytical model of the coupled ocean-atmosphere system over the equatorial Pacific is constructed. The equatorial atmosphere is approximated as a linear feedback system whose surface winds are driven by sea surface temperature (SST) gradients and whose thermal effect is to restore the entire equatorial SST to its maximum value-the SST of the warm-po...

Nonlinear projections (NLP) of the Arctic Oscillation (AO) index onto North American winter (December–March) 500-mb geopotential height (Z500) and surface air temperature (SAT) anomalies reveal a pronounced asymmetry in the atmospheric patterns associated with positive and negative phases of the AO. In a linear view, the Z500 anomaly field associated with positive AO resembles a positive North ...

Tropical Pacific sea surface temperature anomalies influence the atmospheric circulation, impacting climate far beyond the tropics. The predictability of the corresponding atmospheric signals is typically limited to less than 1 year lead time. Here we present observational and modelling evidence for multi-year predictability of coherent trans-basin climate variations that are characterized by a...

Terrestrial paleoclimate records rely on proxies hosted in alluvial strata whose beds are deposited by unsteady and nonlinear geomorphic processes. It is broadly assumed that this renders the resultant time series of terrestrial paleoclimatic variability noisy and incomplete. We evaluate this assumption using a model of oscillating climate and the precise topographic evolution of an experimenta...

Atmospheric variations on multi-decadal time scales, or climate regimes, can cause significant alterations throughout the physical environment, often with remarkable consequences for animal populations and ecosystems. Here we report that the climate regimes in the Baltic Sea area, which are based on the North Atlantic Oscillation and two more regional oceanographic variables, account for the ob...

Separating low-frequency internal variability of the climate system from the forced signal is essential to better understand anthropogenic climate change as well as internal climate variability. Here both synthetic time series and the historical simulations from phase 5 of CMIP (CMIP5) are used to examine several methods of performing this separation. Linear detrending, as is commonly used in s...