In total, 30 percent of olive oil produced in the past five years was made from Picual olives

In second place was another Spanish variety, Arbequina from which 10 percent of the world’s olive oil has been produced over the same period

Along with analyzing which types of olives are being used in olive oils, two authors also investigated how the olives are being harvested and pressed as well as their environmental impact

The two found that 61 percent of olive oils are being produced from traditional groves, while 29 percent come from medium-density olive groves and 10 percent come from high-density groves

Vilar and Enrique Pereira also estimate that each hectare of olive trees sequester about 2.6 tons of carbon, on average, each year (which means each acre sequesters about 0.95 tons of carbon each year)

“International Olive growing sequesters 30 million tons of carbon dioxide, 10 percent of the total carbon dioxide that Spain generates per year