Watch CNBC's full interview with Goldman Sachs' Jeff Currie on energy markets

Investors are gearing up for a big OPEC meeting on Wednesday. Jeff Currie, Goldman Sachs global head of commodities, joins CNBC's 'Squawk Box' to break down investors' expectations. "What we see in terms of the fundamentals and the demand: There is a slowdown occurring, but it's not a contraction,"Currie tells CNBC.