From The Guardian comes a summary of three new studies into the link between human activities and global warming.
Here's The Guardian's summary of the summaries (follow the link for more info)
To summarize, the evidence that humans are the dominant cause of the current global warming is overwhelming (which is the reason behind the 97 percent expert consensus), and continues to grow. And while the media has lately tended to focus on the few papers that suggest climate sensitivity is relatively low, there is a growing body of evidence based on cloud observations that it's actually on the high end, above 3°C warming in response to doubled CO2, which under business as usual would lead to more than 4°C warming by 2100 – a potentially catastrophic scenario.
In short – it's us, it's bad, and if we don't change course, it's a potential catastrophe.