Lawrence Berkeley National Laboratory

Ever wonder what’s in the black cloud that emits from some semi trucks that you pass on the freeway? Lawrence Berkeley National Laboratory (Berkeley Lab) scientist Thomas Kirchstetter knows very precisely what’s in there, having conducted detailed measurements of thousands of heavy-duty trucks over months at a time at two San Francisco Bay Area locations.

Ever wonder what’s in the black cloud that emits from some semi trucks that you pass on the freeway? Lawrence Berkeley National Laboratory (Berkeley Lab) scientist Thomas Kirchstetter knows very precisely what’s in there, having conducted detailed measurements of thousands of heavy-duty trucks over months at a time at two San Francisco Bay Area locations.