Finally some promising environmental news out of China. Traditionally defiant on climate change issues, China in January enacted a new law aimed at curbing pollution. The measure, which accords more powers to punish lawbreaking officials, appears to have been behind the recent closure of steel mills in Hebei and shandong provinces. As this Reuters graphic shows, the breadth and depth of China’s pollution problem is dire. Measured in concentrations of particulate matter 2.5 micrometers in diameter and smaller, 2010-2012 levels in some parts of China were more than seven times unhealthy levels, with Heibi and Shandong among the least healthy provinces. While the the closures will have limited impact on the 1.2 billi0n tons of steel that China produces annually, they are intended as an environmental message with economic teeth. ”Beijing’s battle against pollution will increase costs for steel mills and force those uncompetitive ones to go bust eventually,” Custeel analyst Cheng Xubao told Reuters last week. Promising … with a trust but verify caveat.