Are you ready for some good news -- tiny good news -- about global warming? In a new study, scientists in Boulder say teeny particles called aerosols are helping shield Earth from the sun. As a result, global temperatures just might rise a little less than expected. Thing is, this new study opens up a whole new set of mysteries. Ryan Warner speaks with John Daniel, s a scientist at the National Oceanic and Atmospheric Adminstration in Boulder. The photo shows light from a lidar instrument rising over Boulder. NOAA researchers are using the instrument to study the particles.