From the AP: Carbon dioxide, the gas largely blamed for global warming, has reached record-high levels in the atmosphere after growing at an accelerated pace in the past year, say scientists monitoring the sky from this 2-mile-high station atop a Hawaiian volcano. The reason for the faster buildup of the most important "greenhouse gas" will require further analysis, the U.S. government experts say. "But the big picture is that CO2 is continuing to go up," said Russell Schnell, deputy director of the National Oceanic and Atmospheric Administration's climate monitoring laboratory in Boulder, Colo., which operates the Mauna Loa Observatory on the island of Hawaii.