Here's an interesting read, the experts are still struggling to create models to predict future long term weather trends.
http://www.nature.com/news/climate-forecasting-a-break-in-the-clouds-1.10593
Here's an intresting excerpt, what they're saying is that aeresol pollutants could be masking the effects of global warming, and with the increased focus on limiting aeresol pollutants (coal from coal fired electrical plants is a prime factor), the atmosphere becomes clearer, and could lead to an even higher rate of global warming. Just an example of how complex this issue is, and the effects of unintended consequences. In other words, by "cleaning up" the atmosphere, we may be making global warming worse.
As climate researchers test drive the new generation of models, they are particularly keen to measure the models' overall sensitivity: how strongly they warm up in response to increasing concentrations of greenhouse gases. The addition of indirect aerosol effects makes the new model at NCAR more sensitive to greenhouse gases, says NCAR researcher Andrew Gettelman. Simulations show that the additional cooling from aerosol pollution, as well as the direct effect of haze, masked some of the warming from greenhouse gases during the twentieth century; but the model shows enhanced warming in the twenty-first century as curbs on pollution expose the full power of greenhouse gases. In simplified runs that double greenhouse-gas concentrations — which could happen by the end of this century — the new atmospheric model projects a 4 °C rise in global temperatures, whereas the previous model showed a 3.1 °C increase