The oft-reported figure of 97% could probably use some context, as the figure today, using the latest data, is probably much higher.  The 97% figure comes from a paper published in Environmental Research Letters by Cook et.al., in May 2013.  In that paper the authors explain that they:

"[examined] 11 944 climate abstracts from 1991–2011 matching the topics 'global climate change' or 'global warming'. We find that 66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW, 0.7% rejected AGW and 0.3% were uncertain about the cause of global warming. Among abstracts expressing a position on AGW, 97.1% endorsed the consensus position that humans are causing global warming."

Note that these abstracts included papers from the 90's, when the science was far less certain.  In the past 30 years, the consensus has moved to essentially 100%.  Today, different scientists in the field may disagree about the magnitude, but virtually none of them disagree with the fact of AGW.