Department of Chemistry, Purdue University, West Lafayette, IN, USA

now at: School of Public and Environmental Affairs, Indiana University, Bloomington, IN, USA

Department of Chemistry, Purdue University, West Lafayette, IN, USA

Purdue Climate Change Research Center, Purdue University, West Lafayette, IN, USA

Department of Chemistry, Purdue University, West Lafayette, IN, USA

Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, IN, USA

Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI, USA

Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI, USA

Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, USA

Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, USA

now at: Air Pollution Prevention and Control Division, National Risk Management Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA

Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, USA

University of Michigan Biological Station, Pellston, MI, USA

School of Public and Environmental Affairs, Indiana University, Bloomington, IN, USA

École des Mines de Douai, Douai, France

Université Lille Nord de France, Lille, France

School of Public and Environmental Affairs, Indiana University, Bloomington, IN, USA

Department of Chemistry, Indiana University, Bloomington, IN, USA

School of Public and Environmental Affairs, Indiana University, Bloomington, IN, USA

Department of Chemistry, Purdue University, West Lafayette, IN, USA