22 November 2019

Aridia ~ Towards Oasis Cities in the Drylands?

The WEF writes about Desertification: what is it and why is it one of the greatest threats of our time?
"The combined impact of climate change, land mismanagement and unsustainable freshwater use has seen the world’s water-scarce regions increasingly degraded. This leaves their soils less able to support crops, livestock and wildlife. This week, the Intergovernmental Panel on Climate Change (IPCC) will publish its special report on climate change and land. The report, written by hundreds of scientists and researchers from across the world, dedicates one of its seven chapters solely to the issue of desertification."
The 30 year climate map illustrates the geographies involved (plus see also Koppen climate maps)... In this light, it's worth inverting the issues and seeking opportunities in such drylands.  The big technological achievements of the past half-century are solar power and desalination.  But there's more, including much greater sophistication around water use, shades of greywater, cycling, and design and landscaping for water retention.  Furthermore, reforestation, for instance in the Sahel, has been done with hardier plant varieties and is increasingly including soil modification or assistive techniques to both preserve water and make maximum use of every little bit.  On arid but foggy coasts (e.g. Atacama, Namibia, etc) inexpensive materials are boosting the effectiveness of fog harvesting.  And we can learn from classic desert cities and ancient techniques (e.g. Petra, the medinas, etc) about greening the desert.  In any case, when you stitch all the existing and emergent ideas together, I believe there's a blossoming new category of "oasis cities" in arid regions.

No comments: