The Brazilian state oil company Petrobras will soon begin the process of carbon sequestration in its Lula oil fields to reduce the environmental impact of its deep water exploration. The oil fields, in the region known as the subsalt, contain large amounts of carbon dioxide (CO2) that will now be re-injected into oil reservoirs or sub-sea salt caverns rather than released into the atmosphere. "CO2 re-injection is common in the industry, but it is not common offshore and certainly not at this depth and pressure," said Petrobras engineer Rivadavia Freitas. Environmental regulators have instructed Petrobras not to release CO2 into the atmosphere. Re-injection into oil reservoirs would boost their productivity, but analysts say that it may lead to higher production costs, though sequestration may reduce equipment corrosion. When the sequestration platform is completed, the company could re-inject as much as one million cubic meters of CO2 per day. A recent article in the journal Science indicated that continued carbon release may have a profound impact on the country, as the 2010 Amazon drought suggested the region's vulnerability to rising temperatures. The drought was more widespread than the one in 2005, which had been deemed a "once in a century" event. River levels were at their lowest in a half century, and several tributaries were completely dry, destroying trees and damaging the forest's ability to absorb carbon. For the full story, see http://www.reuters.com/article/2011/02/03/us-petrobras-co-idUSTRE7124PJ20110203. For the story on the 2010 drought, see http://www.bbc.co.uk/news/science-environment-12356835.