Qatar Petroleum Refinery

The world’s 11 “largest” listed oil companies were recently compared on a reserves basis, ostensibly to help investors analyze the firms. But “largest” and “resources” were not defined, and international oil companies were compared with national oil companies, which leaves plenty of questions. [Wall Street Journal]

Mexico announced it will alter its constitution to allow greater foreign company oil sector investment. This is potentially the “country’s biggest overhaul since the passage of the North American Free Trade Agreement in 1994.” However, questions remain about oil companies booking reserves, which could limit investment. [Financial Times]

Climate change is now being blamed for runaway poison ivy growth. “In the last 50 years, the growth rate of poison ivy plant already has doubled.” Apparently poison ivy loves carbon dioxide. [Grist]