1 Division of Earth &Ocean Sciences, Nicholas School of the Environment, Duke University, Durham, North Carolina 27708, USA; and at the Duke Center for Sustainability &Commerce, Duke University, Durham, North Carolina 27708, USA.
2 Nicholas Institute for Environmental Policy Solutions, Duke University, Durham, North Carolina 27708, USA.
3 Division of Marine Science and Conservation, Nicholas School of the Environment, Duke University Marine Laboratory, Duke University, Beaufort, North Carolina 28516, USA.
4 Division of Environmental Science and Policy, Duke University, Durham, North Carolina 27708, USA.