Lately, there have been many explosions around our area and some locals have told me that they are a form of rain-making, as we are in the dry season right now. I started to think about whether humans can make rain and remember back to the cloud seeding that was common in Australia a few decades ago. The Indian rain dances are NOT what I am talking about – the most fluid induced from those would be the sweat on the dancer.
But I started to think about the simple definition of rain-making. This is when below zero temperature seeds of dry ice or silver iodide are introduced into clouds either by rocket or plane to start the process of that cloud releasing its load of moisture. Too often these days our rains fall where they are not needed and the idea is to select a cloud that is hovering over your newly sown crops and make it rain there. Or over the water catchment areas. Would it be useful at all in Australia? Can we convert this continent from being the driest to some happy medium of moisture falling from the sky to rejuvenate our dying rivers?
In a nutshell, yes we can. But what it would require is a rather FAST tree-planting effort, working in from the edges of our green belts and expanding these to probably a hundred times their size and then continuing that process. And then waiting a couple of years for the trees to grow. While, in effect, it probably is not vital what kind of trees to plant, I would advocate the planting of mixed forests of wattles (nitrogen fixers), eucalypts and ashes (tall canopy trees that grow fast), oaks, poplars, nut trees and other introduced species to ensure a better compost effect. New Zealand Coprosmas could be sown in large belts as a fire retardant measure. (This is the mirror bush – the type with shiny leaves you can use to play music).
Tree planting is by far the best and sustainable option as rain is made when terpenes from their leaves are released into the atmosphere. Terpene is a component in resin. These derivatives of tree sap can also come from the swallowtail butterfly so you can see an entire ecology goes towards making rain naturally.
Terpenes naturally occurring in the resin are released by trees in greater quantities during warmer weather. Cloud seeding may speed up the rain process. In the 1950s in Australia it was common for planes to be flying into the clouds to disperse chemicals into them to make it rain. The practice was abandoned because there is no way to run a control experiment to compare what may have fallen naturally. In Beijing, there was cloud seeding a-plenty to combat pollution, fog and to prevent rain happening during the opening ceremony. It seemed to have worked but is unprovable in a scientific cause and effect sense.
Terpenes are a completely natural cloud seeding process as trees continually give off their gases in correct quantities to ensure that rain will fall to keep those trees alive. It’s a nifty cycle of life. Thus tree planting is a MUST. You can read a pretty good article here. As the CSIRO was involved in many experiments they would have plenty of information on the topic.
We should lobby local, state and federal governments to honour Hawkey’s hollow claim that a billion trees would be planted by the time that no child would live in poverty in Australia. Of course, with interest, now that number has more than doubled. And there are still children living in poverty in Australia.
There’s no need to leave it to government though. Plant some trees in your back yard. Individuals can join in any local tree-planting effort and know that you are increasing productive rains by creating new forests.