Observational evidence shows that the Walker circulation (WC) in the tropical Pacific has strengthened in recent decades. In this study, we examine the WC trend for 1979–2005 and its relationship with the precipitation associated with the El Niño Southern Oscillation (ENSO) using the sea surface temperature (SST)-constrained Atmospheric Model Intercomparison Project (AMIP) simulations of the Co...

Changes of the Asian summer monsoon in response to anthropogenic forcing are examined using observations and phase 5 of the Coupled Model Intercomparison Project (CMIP5) multimodel, multirealization ensemble. In the twentieth century, CMIP5 models indicate a predominantly drying Asian monsoon, while in the twenty-first century under the representative concentration pathway 8.5 (RCP8.5) scenario...

A dynamical relationship that connects the extratropical tropopause potential temperature and the nearsurface distribution of equivalent potential temperature was proposed in a previous study and was found to work successfully in capturing the annual cycle of the extratropical tropopause in reanalyses. This study extends the diagnosis of the moisture–tropopause relationship to an ensemble of CM...

This study aims to understand the relative roles of external forcing versus internal climate variability in causing the observed Barents Sea winter sea ice extent (SIE) decline since 1979. We identify major discrepancies in the spatial patterns of winter Northern Hemisphere sea ice concentration trends over the satellite period between observations and CMIP5 multi-model mean externally forced r...

Power spectra of global surface temperature (GST) records (available since 1850) reveal major periodicities at about 9.1, 10–11, 19–22 and 59–62 years. The Coupled Model Intercomparison Project 5 (CMIP5) general circulation models (GCMs) (IPCC AR5 2013) are not able to reconstruct this variability. From 2000 to 2013.5 a GST plateau is observed while the GCMs predicted a warming rate of about 2 ...

The temperature contrast between the Northern and Southern Hemispheres—the interhemispheric temperature asymmetry (ITA)—is an emerging indicator of global climate change, potentially relevant to the Hadley circulation and tropical rainfall. The authors examine the ITA in historical observations and in phases 3 and 5 of the CoupledModel Intercomparison Project (CMIP3 and CMIP5) simulations. The ...

Possible future changes of North Atlantic hurricane intensity and the attribution of past hurricane intensity changes in the historical period are investigated using phase 5 of the Climate Model Intercomparison Project (CMIP5), multimodel, multiensemble simulations. For this purpose, the potential intensity (PI), the theoretical upper limit of the tropical cyclone intensity given the large-scal...

Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Abstract Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Abstract Superimposed on the continued increase in the atmospheric CO 2 concentration is a prominent seasonal cycle. Ground-based and aircraft-based observation records show that the amplitude of this seasonal cycle has increase...

The El Ni~ no–La Ni~ na asymmetry is evaluated in 14 coupled models from phase 5 of the Coupled Model Intercomparison Project (CMIP5). The results show that an underestimate of ENSO asymmetry, a common problem noted in CMIP3 models, remains a common problem in CMIP5 coupled models. The weaker ENSO asymmetry in the models primarily results from a weaker SST warm anomaly over the eastern Pacific ...

[1] Seventeen coupled general circulation models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) are analyzed to assess the dynamics and variability of the North Pacific Subtropical Countercurrent (STCC). Consistent with observations, the STCC is anchored by mode water to the north. For the present climate, the STCC tends to be stronger in models than in observations because of t...