While much is known about marine aerosol generation, little is known about aerosol produced from breaking waves in large freshwater environments or about what implications this aerosol may have for air quality and climate. We present here evidence of significant particle production from the surface of the Great Lakes. In 2009, vertical profiles of the submicron particle size distribution were measured over Lake Michigan, where we found substantial increases in ultrafine particle concentrations with the source at or near the lake surface. The Aitken mode aerosol concentration exhibits an exponential correlation with wind speed, suggesting that breaking waves along the surface were causing the observed particle formation. A calculated dry particle size distribution based on analysis of the lake water shows reasonable agreement with our observed size spectra. This new particle production source is previously un‐studied and could significantly impact atmospheric composition in the region surrounding fresh water lakes.

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This paper argues that planning in the Global South needs to be embedded within a more complex and systemic framework based on understanding cities' functions and transformations, at both local and regional levels, whilst advocating for and incorporating informal and temporary dynamics. This is to differentiate between two competing processes: formal planning and citizen-led place-making, here considered as a form of reactive alternative-substitute place-making that occurs when there is no available alternative. The paper calls for a better integration of such impermanent, adaptable, temporary and alternative forms of place-making into the planning process for regional futures.