Floods Can Reforest The Hijaz.

Floods Can Reforest The Hijaz.

In my last post, I talked about how the water cycle in the Hijaz is disrupted, or sick.  Accurately diagnosing the causes of that disrupted functioning gives us a good idea of how to go about healing the water cycle, and also points to the resources available to us to do that in a sustainable, or even regenerative way.

That post was the last in explaining the environmental and climatic sources of the problem facing the Arabian Peninsula vis-a-vis the lack of rainfall and increasing desertification, as well as some of the political complications involved.  Here is a  summary:

The collapse of traditional rangeland practices in the 1950s lead to a tragedy of the commons and a self-replicating  cycle of desertification that increased dust in the atmosphere, increased surface and atmospheric temperatures, and eliminated many of the organisms that were producing nuclei required for rainfall.  Due to overgrazing and woodcutting, and as the cycle of desertification takes hold, vast swaths of once-lush valleys and mountains are becoming nearly devoid of life, leading to a dramatic loss of productivity and a disrupted water cycle that causes the only renewable source of freshwater to be lost in dramatic flooding events.  As this cycle continues, more and more water will be lost, less and less rain will fall, temperatures will increase, and the productivity of the land will approach 0.

At this time, I am not going to go into the political, social, or economic implications of these facts.  Instead, from this post on, I’m going to be explaining what I believe to be the only sustainable solution that has a chance at saving Saudi Arabia’s and the Arabian Peninsula’s water and food security issues.

The most valuable resources in the current water cycle are the floods that periodically rush through the wadi systems of Saudi Arabia’s west coast.  These floods (and other rains) constitute the only sustainable source of water in the entire Kingdom.  Fortunatey, these floods can be used to establish systems that will make the water cycle more regular, that will increase its cyclical frequency, as well as amplify the total amount of rain that falls.  In short, we have to use the floods to bring the rain back, and it can be done in such a way that the total precipitation increases, and the frequency of rain events increases.

The first part of this series will be all about trees and the wondrous effect they can have on the water cycle.  Here is the map, tho not a table of contents:


A pictured Mongongo Tree

Moderating Rainfall, Surface Water Flow & Water retention. 

1:  Clay pan penetration

2:  Erosion reduction, soft rain catching

3:  Hydraulic redistribution

4:  Soil moderation–increasing carbon & soil life increases water retention

Tackling the Problems of Dust, High Surface Temperatures, & Lack of Raindrop Nuclei

5:  Evapotranspiration–VOC’s, vapor, & litter

6:  Moderating hot, dry winds

7:  Extending evaporation periods while reducing evaporation from bare soils

8:  Shade, specific heat, and lower soil temperatures

9;  Wind & dust break

Providing Additional Sources of Precipitation

10: Increased condensation

This is going to get sciencey, but I promise that it will be awesome.   Here’s the first taste of awesome:  Did you know that trees can store water in the soil near their taproots during wet times and then pump it back up to their shallow roots when the soil is dry?  This is called hydraulic redistribution and will be the topic of the next post.


  1. Always leaving us in suspense.

    • There’s a lot more to go before all the loose ends are tied, Joel!


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