OVERNIGHT ENERGY: Carbon dioxide levels hit new high

‘A SIGNIFICANT MILESTONE’: Scientists with the National Oceanic and Atmospheric Administration announced Wednesday that global average carbon dioxide in the atmosphere in March was over 400 parts per million for the first time since records began.

Pieter Tans, lead scientist of NOAA’s Global Greenhouse Gas Reference Network, called passing the 400 per million mark a “significant milestone,” and said that it was inevitable, given carbon emissions from human activities like burning fossil fuels.

“This marks the fact that humans burning fossil fuels have caused global carbon dioxide concentrations to rise more than 120 parts per million since pre-industrial times,” he said. “Half of that rise has occurred since 1980.”

{mosads}Scientists and environmentalists believe that somewhere between 350 parts per million and 450 parts per million marks a safe level to prevent catastrophic climate change.

While hitting 400 itself makes little difference, it nonetheless can add urgency to the fight against greenhouse gas emissions for greens and others.

Read more here. 

ON TAP THURSDAY I: Six Senate Democrats will hold a press conference on the biodiesel mandate in the renewable fuel standard, and to urge the Environmental Protection Agency to finalize a strong standard.

ON TAP THURSDAY II: Sens. David Vitter (R-La.), Tom Udall (D-N.M.) and other supporters will hold a press conference to talk about their efforts to reform the Toxic Substances Control Act. Their measure passed the Environment and Public Works Committee last week.

Rest of Thursday’s agenda …

Robin Dunnigan, the deputy assistant secretary of State for energy diplomacy, will speak at an Inter-American Dialog event on Central American energy. 

Reuben Sarkar, the Department of Energy’s deputy assistant secretary for transportation, will be part of a panel discussion on how the energy boom could impact transportation.

The Woodrow Wilson Center will hold a forum on the Quadrennial Energy Review. Melanie Kenderdine, the director of the Energy Department’s Office of Energy Policy and Systems Analysis, will participate.  

AROUND THE WEB:

Hawaii’s legislature passed a bill to end its ethanol mandate, the Associated Press reports. It would be only the second state to repeal an ethanol mandate.

The mayor of Las Vegas has pledged to lie down on a highway to stop nuclear waste from being shipped to Nevada, the Las Vegas Review-Journal reports.

Time has a photo gallery of the ways California is coping with its dwindling water supply. 

IN CASE YOU MISSED IT:

Check out Wednesday’s stories … 

-Senator pushes bill to speed up pipeline approval
-Oil train derails, explodes in North Dakota
-Senator pushes bill to modernize energy
-Carbon dioxide hits new milestone
-Carson in Iowa: Use oil subsidies for ethanol
-Canadian province loses pro-Keystone leaders

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