Here is a look at some of the transportation headlines gathered by us and the Metro Library. The full list of headlines is posted on the library’s blog.

First fuel efficiency and greenhouse gas emission standards announced for trucks (L.A. Times)

Emphasis on the word “first.” Although trucks and heavy vehicles make up only four percent of the vehicles on the road, they use 20 percent of the gas due to the long distances they travel, their weight and corresponding lousy mileage. More emissions equals more pollution, of course, and the new rules are designed to cut those emissions by 20 percent and raise trucks’ average six miles per gallon to eight. The announcement by President Obama comes on the heels of his release of new fuel standards for cars to an average of 54.5 miles per gallon in 2025. If all this gets implemented, it could be a nice punch to the face of air pollution — if, and it’s a big if — Americans don’t go hog-wild driving and find ways to burn more gasoline.

Alex Steffens: We can’t avert climate change without dense cities (Streetsblog Capitol Hill)

The urban writer argues that we can’t avoid climate change simply by switching to cleaner fuels — we still burn too much fossil fuels. His argument: the only way to seriously reduce greenhouse gases is to live in denser cities where people don’t have to drive everywhere to do everything. This post also includes a fascinating — albeit older — chart comparing population density in cities to the energy consumed by transportation. Not surprisingly, European cities fare well, American cities don’t. I’m not sure Moscow is still all that efficient, however. By most accounts, traffic there has gotten pretty bad as vehicle ownership has soared.

A tale of a cyclist hit twice by a motorist (Grist) 

Need to feel your blood boil? Read this scary story about a cyclist in Mississippi hit from behind by a woman motorist who allegedly was using her cell phone at the time. It gets worse. After the accident, the motorist got back in her car and ran over the cyclist a second time. The cyclist is recovering, and the motorist may only be charged with a misdemeanor. Mississippi, btw, doesn’t have a law against using a handheld cell phone to talk and/or text while driving.