I noticed in one of the local small newspapers an article about an attempt to artificially make rain down at Willunga. To say that the concept of rain making is controversial is probably an understatement and the whole has a rather sordid past of scams which more than overwhelm the few successes. Now before my dear readers start thinking I’m about to rip into this latest endeavor lets just hold our horses and examine one very well documented place where this happens … for real. Tasmania.
Yes, that little annoying and poky island off our south coast has been artificially boosting their rainfall for many years.
To read it all go to here but for a brief summary, please read on. The basic idea is to seed into appropriate clouds with iodine salts, these form nucleation centers and hence rain falls that otherwise might not have. The two points to making this a success are “appropriate clouds ” and “into”. They hydro guys and gals spend some serious time choosing the clouds they will get best success from considering the prevailing weather and very carefully choose the flight path of the planes which do the seeding. This is not a cheap process and they get their bucks from the extra water generating extra power via hydroelectric generators on the dams. They also did a lot of good research early on with CSIRO to make sure it actually worked. So how do we know when things actually work? Glad you asked, answer is…the scientific method. So what is science, and no, it’s not a list of boring facts dull uninspiring science teachers are wont to trot out, especially those with no background or interest in science, which is most of them. Here’s a list I grabbed from a book many years ago and it’s stood the test of time. (And sorry , I don’t have the name of the name, I really, really wish I did.)
- Science is logical and rational.
- Science makes well-defined claims.
- Scientific hypothesis are falsifiable.
- Scientific experiments are repeatable.
- Science requires that claims are examined by peers.
- Science views unexpected gaps in theories with suspicion.
- Science requires caution in examining evidence.
- Science requires objectivity.
- Science does not accept coincidence as proof.
- Science does not accept anecdotal evidence as proof.
In real science at least 9 out of 10 of the items will be supported. If you get less than that, then you soon drift into pseudo-science and once you’re down to not many that’s the land of woo.
So let’s look at Tasmanian cloud seeding.
Point 1, yes, putting nucleation centers into clouds does make sense because that is exactly how raindrops form normally.
Point 2, yes, they explain a lot on their FAQ page. They also state their expected improvements in rainfall and where it will fall. Furthermore the CSIRO also explain under what circumstances this will and won’t work here.
Point 3, yes. When they developed their process their testing included a both seeding suitable and not seeding suitable clouds. This was a test to see if what they did had a causal relationship with what they observed.
Point 4, yes. As far I can be seen, at least 5 sets of experiments to reproduce the effect. This makes simply financial sense. Hiring planes is expensive. Hiring skilled people isn’t cheap either. Why waste money if it didn’t work?
Point 5, yes. They got the CSIRO to examine the results which has a brief summary here.
Point 6, yes. The theory was robust and they actually ran experiments to close as many gaps as possible. AS such the CSIRO found that cloud seeding would not work in many places in Australia.
Point 7, yes. They repeated the experiments over a long time span.
Point 8, yes. There isn’t hype about this working in Tasmania, it doesn’t have high profile media people ranting on how great this will be.
Point 9, yes. The first results looked promising. Did they just go with this? Nope, the repeated the experiments again and again, looking for a testing the variables that affected the results.
Point 10, yes. They actually did the experiment and allowed for the effect to not work.
So that’s how to do it properly. This latest mob down at Willunga initially had the CSIRO involved but they are no longer in the testing program.
Let’s go through the points for the latest proposal by Australian Rain Corporation.
Point 1,Is it logical and rational? Ok, so what does this thing actually do? It releases negative ions at ground level. These negative ions go up into clouds, react with oxygen and make it rain. A few questions spring to mind about how rational this is. How do the ions actually get up into clouds and can they get high enough? What sort of clouds? Why don’t the ions bond with oxygen in the air normally before they get up into clouds or doesn’t it really matter where this happens. (In which case, why say it?)
Moving on to point 2, well defined claims. They make no mention of what the conditions need to be for this to work. What sort of clouds? What sort of wind pattern? What humidity? How much do they expect? Without knowing exactly what they are claiming it’s going to be hard to tell if they have succeeded. Even the testing procedure isn’t clear no explained anywhere. This could be done without giving away trade secrets but there is no information given. They don’t even mention how they are performing their test.
Without having a well defined claim it’s going to be hard to prove them wrong so point 3 is a fail. In previous tests in Queensland the results where inconclusive but it appears their experiment was pretty badly designed compared to what CSIRO did. TO make it falsifiable they need to sometimes run the machine when they think it might cause more rain and to also not run it when weather conditions are suitable and compare the results. Comparing rainfall from different areas is pretty poor experimental design when there is a better way to do it.
As for peer review I have been unable to find any peer reviewed reports concerning the Queensland trials. Yes, I’ve seen the summary of claims but I actually need to see the report to see how the experiment was done. Snappy headlines don’t cut the mustard.
With regards to gaps in theory, well there are plenty. It’s simply not supported by any. There is a fundamental problem of how the negative ions cause rain, if they could get to where they are needed, if they didn’t react on the way up, if they are special in quantity or quality from what’s already in the atmosphere.
At least they are being a bit cautious with the poor evidence to date although as I have mentioned there is very little to actually examine. The objectivity aspect they are attempting but there are so many missing facts from a real scientific experiment it simply doesn’t look right. (And I wont go into the structure being comprised of pyramids, if nothing else that’s really poor marketing as it attaches a woo factor to the whole thing.) And we’re not accepting the results from Queensland in case they are just a coincidence and at least unlike many dodgy bits of woo like dowsing, the web site hasn’t an anecdotal testimony page.
So what to make of it all? Based on what has been made public it’s unproven pseudo-science at best but at least they are doing the experiment. Their current experiment is not very scientific as it would appear they are just turning the machine on for 3 months to see what will happen. Hopefully there is moer to the test than this. The problem with this method, which appears to be what was used in Queensland, is that we wouldn’t know what would have happened if it wasn’t turned on. There is so much variability in weather, let alone potential climate change, that comparing side by side areas really doesn’t appear to a very valid approach. Especially when the CSIRO has already demonstrated a better protocol and has it publicly available!