Urbanization represents one of the most visible land cover changes of the past two centuries. In Latin America, it has resulted in a massive expansion of impervious soil surfaces, which has led to dramatic land degradation. In particular, the expansion of impervious soils interferes with the natural process of water infiltration and increases surface run off, which in return exacerbates the magnitude of pluvial floods. Simultaneously, under the effects of climate change, the frequency of extreme rainfall events is already increasing in most Latin American cities. Against this background, the ability to preserve and rehabilitate urban green spaces has been increasingly mentioned as an option to reduce urban flood risk and adapt to these new trends. To provide empirical evidence of these potential effects, this communication assesses whether a greener urban land cover can reduce the impact of extreme rainfall events on local economic activity. To this end, a dataset of 557 cities across seven Latin American countries is assembled using the “Degree of Urbanization” concept. Earth Observations are then used to compile information at the city level on (i) rainfall patterns, (ii) land cover features using NDVI composites and (iii) local economic activity proxied through night-time light intensity. Using fixed-effect econometrics, the relationship between extreme rainfall and night-time light at the city level is assessed over the period 2013-2021. The role of urban green areas as a mediating factor is further explored. Findings indicate that cities displaying a higher share of urban green areas are less severely impacted by extreme rainfall events. Altogether these results highlight the crucial role that a more balanced urban land cover can play to foster sustainability.

Rafael Van der Borght ; Montserrat Pallares Barbera
Universitat Autonoma de Barcelona – Departamente de Geografia

 
ID Abstract: 387