1 The transport of the Antarctic Circumpolar Current (ACC) varies strongly across the cou2 pled GCMs (general circulation models) used for the IPCC AR4. This note shows that a 3 large fraction of this across-model variance can be explained by relating it to the param4 eterization of eddy-induced transports. In the majority of models this parameterization is 5 based on the study by Gent and McWi...

[1] The coupled global atmospheric-ocean models used for transient simulations in the IPCC AR4 report differences in the present-day shortwave forcing of more than 2 W/m. We show here that about 1.3 W/m of this spread could be explained by the different methods used to calculate cloud droplet number concentration (CDNC) from aerosol mass concentrations. Although we cannot rule out that other fo...

1 The transport of the Antarctic Circumpolar Current (ACC) varies strongly across the cou2 pled GCMs (general circulation models) used for the IPCC AR4. This note shows that a 3 large fraction of this across-model variance can be explained by relating it to the param4 eterization of eddy-induced transports. In the majority of models this parameterization is 5 based on the study by Gent and McWi...

[1] We survey the IPCC AR4 models’ responses to SRES A1B forcing in order to evaluate a prediction of climate change common to all models and testable using GPS radio occultation data over the coming decades. Of the IPCC AR4 models that submitted runs of the SRES A1B forcing scenario, we select twelve because of the timeliness of their submission. Trends in the global average surface air temper...

The Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) assessed a range of scenarios of future greenhouse-gas emissions without policies to specifically reduce emissions, and concluded that these would lead to an increase in global mean temperatures of between 1.6°C and 6.9°C by the end of the twenty-first century, relative to pre-industrial. While much political at...

many researchers have investigated how to increase the overall efficiency of solar-driven thermal systems. several key parameters, such as collector efficiency and storage tank characteristics, may impose some constraints on the annual solar fraction (asf) of such systems. in this paper, the behaviour of integrating the phase change material (pcm) in sdhw systems is modelled and optimized numer...