Reducing the speed limit to 50 mph, say researchers, would create the tipping point where taking transit or modes other than driving will become more attractive and therefore save CO2 emissions.
Also, it turns out that driving slower reduces emissions.
From Wired: "The faster you go, the more fuel you burn because wind resistance increases exponentially. Lowering your speed by 5 mph when traveling at 35 to 45 mph will boost fuel economy as much as 10 percent (.pdf), according to a report the General Accounting Office prepared in 2008."
Treehugger takes the Wired article a step further, presenting six reasons why slowing down is beneficial. For one:
"It could save a lot of fuel. Some estimates indicate up to 5%; In 1983, by which time many people were ignoring it, it saved 2.5 billion gallons of gasoline and diesel, or 2.2% of the total fuel used. Oil was a horrible $ 20 per barrel. Wired notes that "The Department of Energy noted in 2008 that lowering the national speed limit to 55 mph would save 175,000 to 275,000 barrels of oil daily."
FULL STORY: Slow Down and Spare the Planet

Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

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Trump Prompts Restructuring of Transportation Research Board in “Unprecedented Overreach”
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