Today, was attempting to study for my Environmental Biology exam and was reading about climate change. I've lived without a car for the past four years, walking (and for a year using my bike) to get to work, school, and stores. My terrain is limited, and I'm awed the rare times I get a ride on the highway.
I remembered the HOV lane from my childhood in Georgia, and decided to look up what all those were about.
http://en.wikipedia.org/wiki/High-occupancy_vehicle_lane
I'm pretty enthusiastic about these--I suspect the one I remember from childhood was motivated by a desire to reduce traffic congestion, but carpooling would be a great way to reduce greenhouse gas emissions (and encourage social behavior). I'm not sure to what extent people actually change their behavior to utilize these travel-time benefits, though.
From the wikipedia page: "According to the FHWA, among the HOV facilities with utilization data available, the HOV facility with the highest number of peak hour persons in the HOV lanes is the New Jersey Route 495 Lincoln Tunnel bus lane, with 23,500 persons in the morning peak,[4] and 62,000 passengers during the 4-hour morning peak.[7]"
This blew my mind. 62,000 people moving EVERY DAY in giant metal vehicles through just one lane to and from a location. It makes no sense to my mind why people would move back and forth that much--it seems so inefficient, and is just mind-boggling in scale, and then to think that similar mass movements of people must happen in many, many more locations...