THERE has been no general decline in rainfall in Australia due to global warming. But it is possible that the Murray Darling Basin, once regarded as the food bowl of Australia, will get even drier.
When farmers say that the region has never been as dry in their lifetime they are correct. However, the data clearly show that over south eastern Australia the first half of the 20th century was much drier than the second half and the recent ‘drought’ is a return to the conditions of the early 20th century. Also, the recent dry period is not yet as dry as the period from about 1935 through 1945.
The Bureau of Meteorology (BOM) have taken the station annual rainfall since 1900 and created maps of annual rainfall. They have then calculated the average annual rainfall within various regions, including the Murray Darling Basin region. At the website the BOM also have this map which shows the annual departure from the average (anomaly) together with the 11-year average plotted on the 6th year of the averaging period.
The data are available at:
http://www.bom.gov.au/cgi-bin/climate/change/timeseries.cgi?graph=rranom&area=mdb&season=0112&ave_yr=11
Click on the graph for a better larger view.
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Jen,
Where was this graph when everyone was screaming recently, “worst drought in 1000 years!”?
So the 30’s “dustbowl” was not just confined to America or even the Northern Hemisphere? Are you implying that this “warming” was “Global”? But I thought I read that Global Warming was caused by the 6 billion people on this planet who have pushed us past peak oil running cars and factories on oil and coal for 50 years. Your scientific evidence flies in the face of that, indicating an early century warming that couldn’t have been caused by these Anthropogenic factors.
Well, sorry for you and science, but I’m gonna believe Al Gore. Have you ever seen the size of the projector screen in his movie. Anyone with a projector screen that big HAS to be important, famous, and therefore right about everything. You’ve probably never even been on TV.
Just proves what a joke this whole alarmist nonsense has become.
I’ve lived through the whole of that second WETTER half century on the Murray and remember the incredible flooding, but I suppose the leftwing idiots will claim that it wasn’t NATURAL as well.
Why did they ever listen to these idiots, but Jennifer I sincerely hope we don’t experience a similar period like 1935 to 1945 because if we do a lot more hardship is yet to come.
maybe it’s more about how we handle the water in the catchment.
Are there any maps showing the extend of agriculture in the basin over the same time period? My understanding is that today we have much more agriculture in the marginal areas – so the drought experienced by many farmers is worse than it has ever been – as they were seduced in to more marginal land in the wetter period.
I agree MattB – there have been huge irrigated vineyards established all along the Hay plain in the past 20 years.
What janama and MattB said.
Water in minus water out equals water remaining. Very little water remaining equals drought.
No doubt this will all spin off into a useless AGW-connection distraction, but the point is that we need to take less water out of the system. Particularly if, for whatever reason, we can expect less coming in.
It strikes me as strange that the BoM produced a graph showing anomalies over the period 1900-2008 using a baseline for 1961-1990, smack in the middle of the apparent wetter phase of the climate. This is why many more years show a dry anomaly than a wet anomaly. I’d be interested to see how the graphs and maps appeared if based on 1900-2000.
This website:
http://gustofhotair.blogspot.com/2007/10/more-rain-and-no-change-in-drought-and.html
shows that every state of Australia has had an increase in rainfall since 1950 when compared to the 50 years before that. In fact, the increase since 1950 has been on average 9.5% greater. Critics will argue that this is due to long periods of drought and occasional heavy rains. But the website shown above will show that there is no increase or decrease in amount of heavy rains australia wide, as well as no increase or decrease in consecutive dry days.
A picture is worth a thousand words, and a good graph is worth more.
Also worth considering is that the base period for anomaly comparison (1961-90) appears to have an average above the average for the whole period (1900-2008). I wonder how many other often quoted statistics use a base period that is similarly unrepresentative of the longer term situation?
I’ve never been to your charming country, but there may be an historic parallel with the Colorado River in the Western U.S. There was an agreement between my country and Mexico that allocated the water in the Colorado. But the assumptions about annual flows were unrealistic. The result? The river delta has been a desert for for some time. Some of the local residents would probably enjoy seeing at least a remnant of the old riparian habitat.
“No doubt this will all spin off into a useless AGW-connection distraction,”
No one’s mentioned AGW but seeing as you did, you might recall that it was the AGW alarmists who have been pointing to this “unprecedented” drought as proof of our guilt.
That is AGW guilt, not excess usage guilt.
MDB is a big place eh?
hahahahahahahahaha !
I am neither a scientist nor a statistician, but I believe this graph is meaningless.
The MDB is 100million hectares in area and represents 14% of the Australian landmass.
Within its boundaries are a range of dispatate climate regions. From the mostly summer rainfall of the rolling hills of southern central Queensland, through mostly desert regions of western NSW to the high precipitation mountain regions of NE Victoria.
So large and diverse is this area, that is home to 3 M people and produces 43% of Aus. total agricultural production, that we often see events like at present.
Where the Darling catchment which has been dry for years is now largely out of drought, while the Lachlan and Murrumbidgee valleys are still without worthwhile runoff rain.
Why the B of M would want to average this out and how they thought this could be of some use is beyond me.
From all of the records which I have I do support the claim that if there is no flooding in the system this year then it will be the longest period since the arrival of whiteman.
To Matt B And Janama, THe MDB contains large areas of both dry land farming and irrigated agriculture. The development of the Mallee soils for wheat, sheep farming was completed by about 1950 and all that has happened since is the amalgamation into larger holdings. While it can be claimed to be rainfall marginal, these farmers are profitable and as efficient as any in the world.
In relation to irrigated agriculture, while State sponsered irrigation areas have been in existence since the early 1900s, there was a huge increase in irrigation on most of the valley flood plains during the 1970s and 80s.
I was was involved in quite a lot of this development on the Murrumbidgee and Lachlan rivers.
However, as I have said on this site before and others places, what is presently being claimed by many is simply false!
Irrigators do not and have never owned any water.
The water of the MDB is owned by the State authorities.
Each year NSW Water (previously WCIC) assess what water is in storage and likely inflows and then allocate that water as follows:
1: Stream flow and stock and domestic, which includes town and city use.
2: All contractual agreements with other states, mostly SA.
3: First priority for remaining water to farmers with permanent plantings. (fruit trees and vines.
4: Any remaining water is made available to irrigators with licences for annual plantings.
If NSW Water decide there is only sufficient water for the first 3, then other irrigators get no water.
This has been the case for the last several years.
BUYING WATER LICENCES FROM IRRIGATORS ACHIEVES NOTHING!
To FDB, water remaining in the rivers s largely unrelated to drought.
Pikey.
As usual Jen fails to report on the contemporary interesting climate science on the subject.
Doesn’t mention inflows.
Doesn’t do antecedent conditions and clustering.
Doesn’t give a spatial context.
As usual with the ol’ shell game – leave out half the shells. Good propaganda strategy.
But hey we’ve been over this about 20 times. If you haven’t cottoned on by now – try Fine Cotton.
But denialists will buy anything – why bother getting all sophistmuckated.
Last August I was in Echuca and took a ride on a steamboat up the Murray River, a peaceful and happy experience. There was time to look around at an unfamiliar landscape. On the south (Victorian) side of the river it was mostly red gum bush, possibly park or State forest, I couldn’t tell. But on the north (NSW) side the banks of the river had been subdivided and developed into small rural holdings and kilometres of side-by-side holiday cottages. Each of them had its pipe down to the river and its electric pump, and surrounding the houses were patches of vivid green lawns and irrigated fruit trees. I have no idea how significant this use of river water is, probably trivial in the overall context of the the Murray, but it spoke to me of a profligate society, and one where government planning is hopelessly short-sited to allow this sort of development right on the river bank.
Later I drove on the NSW side of the river to Albury, and found that a feature of agriculture in this area is dairy farming on irrigated pastures. The vast quatities of water being applied must have been coming straight out of the Murray, or from near-river aquifers which amounts basically to the same thing. I don’t blame the farmers, who presumably have permits and quotas dished out by the government. However, I think of these two things every time I hear people saying that the Murray is going dry because of global warming.
Pikey – On a hot summer’s day I swam in the Murrumbidgee river. It was 40 degrees in the sun and I froze in the freezing Murrumbidgee river. How and ecology could exist in that environment beggars belief, more than ten minutes in there and you’ll have a headache, just like Torquay in winter. That’s where it all starts, the screwing around with the water yet on this part of the island, water is precious.
Hi Jennifer,
An interesting article pointed out by Jonathon Lowe. It reminded me of the rather absurd claim made by AGW alarmists that increasing temperature will cause droughts. The more obvious likelihood surely is that slightly increased sea temperatures will cause increased evaporation and more rainfall.
A more general comment:
What sin did you ever commit to have Luke inflicted on you. What did we readers ever do to deserve him.
Luke, why don’t you give it a rest.
Why do you like nonsense Alan – are you all up for bad science (certainly your comment indicates you came down in the last shower)?
Half the story your cup of tea mate ?
And “AGW alarmists that increasing temperature will cause droughts” – says who?
Hi Janama,
I have not said there were not environmental problems within the MDB.
What really annoys me and everyone who has some understanding of the system and the health of the river eccology, is that while Brown, Wong, Sinclair Garrett and their Media Support Gang have been trumping up false claims, really serious environmental problems have been totally overlooked or neglected.
The release of cold water from the bottom of dams is a problem (although not as severe as you may claim). However it is an engineering problem that is realitively easy to overcome.
A much greater problem is European Carp.
I challenge the people listed above to explain to all, if they have the welfare of the MDB at heart, why are they avoiding this issue?
Could it be because there is no identifiable scapegoat?
To all above!
The Murray is not dying.
The river red gums are alive and well.
The drought is all but over.
Luke, you backslider. You have repeatedly claimed that the shortage of water in recent times in the MDB was a direct result of AGW,
Stupidity I can tolerate.
Lying I cannot.
Pikey.
Lying you cannot eh Pikey – yea – me too.
I said there is a good reason to suspect AGW involvement in the drought.
Didn’t say it was “caused” by high temps. That might add to the effect somewhat.
Like determined denialists might – you wouldn’t be trying to verbal me would ya?
Isn’t it strange Pikey mate – that somehow Jen’s lead post just funnyily enough seems to forget items like:
“Murray system inflows: In response to the below average rainfall, Murray system inflows have reduced to historically low levels. The three month total of 140 GL for January to March 2009 was slightly lower than the previous historic minimum of 150 GL in January to March 2007. Inflow for the 2008-09 water year is currently tracking as the 6th driest in 117 years of records. The persistence and severity of this drought, particularly over the past three years, is unprecedented.”
http://www.mdba.gov.au/system/files/MDBA_Drought_Update_April_2009.pdf
And Pikey – isn’t even funnier that although no case for AGW supposedly exists – well it’s just so strange that all those papers on IOD, SAM, STR, Walker circulation that show an AGW influence at play – somehow – don’t know how – those papers just keep fallin’ through them thar cracks.
You’d have to to wonder wouldn’t you?
But Pikey – let us not concern ourselves with relevant information.
However, the data clearly show that over south eastern Australia the first half of the 20th century was much drier than the second half and the recent ‘drought’ is a return to the conditions of the early 20th century. Also, the recent dry period is not yet as dry as the period from about 1935 through 1945.
dear Jennifer, rainfall is not the only factor affecting “drought”.
surprise surprise, but temperature might have an effect as well.
think about it.
Luke, got caught out again, I see. Tsk, tsk! Weasel wording something just to cover your arse? your arguments are getting wilder, louder, weaker, and more angry.
Am I correct that when I look at this graph and add ‘guesstimates’ for each these periods, I get these approximate numbers?
Taken over 5 year period
5 year average 1900-1904 (incl) – minus 500mm anomaly 5 year average 2004-2008 (incl) – minus 350mm anomaly
Taken over a 10 year period
1900-1909 (incl) – minus 630mm anomaly 1999-2008 (incl) – minus 540mm anomaly
And the figures for 1895 -1899 are not available (the Federation Drought went from 1895-1902+). However, the rainfall figures for Deniliquin on the Murray show below average rainfall there for each of those pre-1900 years. In fact, from 1895 – 1906, Deniliquin only had one year above average rainfall (1906).
The cycle of drought starts again (once in a hundred year drought?) but there was no AGW or warming at present trends then to cause those 1900’s low rainfall figures.
How CoRev? Put up or shut up.
kasphar – at the same time as the federation drought northern Australia was flooding, just as it is now and I assume Lake Eyre was full as it is now.
I agree with DanP and Peter Pond, this use of an atypical 30 year mean to graph a 100 year anomaly series is at least deceptive, and more likely, downright sinister. If the mean of the entire data set was used then the past decade is unremarkable.
And as I have stated before on this blog, there is absolutely no excuse for EVER publishing an anomaly series without displaying it in the actual scale of the records. The mean rainfall for the MDB is about 500mm per annum so the maximum positive anomaly of +300mm should be shown on a vertical scale to +800mm with the negative anomaly of -250mm shown as +250mm on the graph.
This would provide a much truer picture of the situation with a total amplitude of variation being 110% of the mean.
Hi Luke & All,
I think most of us here are ONLY concerned with relevant information. So here is some for you to consider Luke:
As mostly agreed above this graph is a useless waste of effort.
However in relation to the claims you have posted relating to storage inflow, you may consider this:
There was NO stream flow monitors prior to the 1960s. Claims of lowest stream flows for 117 years are ludicrous, as there were no dams built then.
This is at best wild guesstimates.
However here are the facts as at May 4th 2009.
DAM Capacity %09 %08 Present storage.
Megalitres
Blowering 1.6M 30 24 480,000
Burrendong 1.2M 20 16 240,000
Burrinjuck 1.01M 38 41 384,000
Carcoar 36,000 9 7 3,000
Chaffey 62,000 98 76 61,000
Copeton 1.36M 13 21 177,000
Dartmouth 3.9M 21 16 816,000
Hume 3M 4 7 112,000
Keepit 425,000 35 24 149,000
Menindee 1.7M 13 33 221,000
Windamere 368,000 23 24 149,000
Wyangla 1.2M 7 11 84,000
Eildom 3.2M 13 13 407,000
Yarrawonga 140,000 88 68 103,000
TOTAL STORAGE AS AT MAY 4th 2009 3,186,000 megalitres.
Luke this is the present position and does not include a number of smaller storages.
In relation to inflow, which I check every week, while it is still low, there is increasing flows into most storages as the area under drought continues to decrease.
In relation to how long it would take for this situation to turn around and have most of the dams near capacity.
With the exception of Dartmouth on the Mitta Mitta, which is the biggest storage in the system, outside the Snowy; it could happen very quickly with above average winter or spring rains,
Just because it has been so dry for so long, it is false to say the dams will take years to replenish.
I have seen Burrinjuck fill in 2 days.
Things are not as bad as you and the MDB group may like to wish for to support your AGW sensationalism.
Pikey.
again, temperature changed as well. looking at rain only is simply a false approach.
could those who are trying to talk away the drought please talk to a farmer now or then?
How tedious you are Pikey
(1) most of the storages you’ve mentioned don’t flow into the upper Murray. So don’t bung on the irrelevant listings.
(2) the Murray River is the record drought affected system as MDBC state
(3) the mechanisms for the Murray system missing out on rain are now confirmed in obs and reproduced in models – changes in Southern Annular Mode, sub-tropical ridge, Indian Ocean Dipole and Walker circulation – all manifesting in ongoing drought sequences resulting in unprecedented calculated inflows. The science points to an involvement of anthropogenic effects from decreasing stratospheric ozone combined with increasing greenhouse gases and overlaid over natural variation.
(4) of course water monitoring doesn’t go back 117 years and dams are relatively recent. But somehow I think the MDBC know this. It’s relatively simple to derive a well validated model of inflow for the purpose of transforming the historical rainfall record in water inflows. This is hardly new or even difficult despite your sneering.
(5) back to back years of dry, and antecedent conditions – a dry catchment – means that this sequence is now worst on record. I think the farmers affected may have even worked it out for themselves.
(6) worst on record doesn’t prove AGW involvement either. But the science above mixed with a record dry on the Murray gives the hypothesis of AGW prolonging the drought – adding to it – HEAVY weight. Not perfect weight – but heavy weight.
(7) mid-latitude drying effects are predicted by the AGW models – but the involvement of Antarctica makes the situation more complex.
(8) Yes it will rain again sometime (maybe even quickly – maybe not) – otherwise we are truly stuffed. But the question is how long till the drought sequence reoccurs. This sequence has its roots in the 1990s.
The probability of you taking any of this on board or even following up on the science is minimal so why do I bother?
Frankly Jen’s treatment of the situation is shoddy and blatantly political.
Regarding Sod comment about higher temperatures affecting the drought, it is my understanding in the Northern Hemisphere at least, the rise in temperatures has occurred mainly in winter/spring and at night, (less evaporation?) rather than in summer and in daytime.
Interesting to see that graph. I spoke to a rice farmer from Riverina whose family has lived in the area for 150 years, and he said that the present drought was the the THIRD worst, not the worst, from their records. They grew sheep/wool in the early days and only moved into rice when the irrigation scheme and wetter years arrived. No rice for several years now.
So it is the number of users of the normal water that is the problem.
Hey Luke,
Do us all a service and read your post again and then try to convince us you are not on the “funny weed.”
Your post makes no sense, or you have no understanding of the MDB.
Possibly both.
Your reference to the MDBC report was not confined to the upper Murray.
Your response is garbage.
Pikey.
The Federation Drought started in 1895. If you add those years to the ones you see in the graph, I can’t see how you can say this recent drought is worse. The first 10 years at the beginning of the last century was drier Aust-wide than recently (ie 1999-2008 incl) and if you look closely at the graph above, you see the same pattern for the MDB (regardless of sequence).
Some areas went from 1895 – 2005 before the drought broke (ie Deniliquin). The BOM had this to say about the Fed drought.
‘The five years leading up to Federation (January 1901) saw intermittent dry spells over most of the country, particularly in 1897 and 1899; in most of Queensland, dry conditions were virtually unbroken from 1897.
Rivers in western Queensland dried up; at Bourke, the Darling River virtually ran dry. Further south, towns near the Murray River such as Mildura, Balranald and Deniliquin – at that time dependent on the river for transport – suffered badly. The Australian wheat crop was all but lost, with close to the lowest yields of the century.’
And from
http://www.abc.net.au/water/stories/s1836657.htm
“During the federation drought, 50 per cent or more of stock died of thirst or starvation. “You could walk or drive a horse and cart across the Murray River. It had completely dried up around Swan Hill and around north west Victoria.”
So, ‘worst on record’? Very debatable.
I don’t care what the post is about. It’s standard sleight of hand by Jen to say there’s no AGW in the MDB – when there arguably is a case. Next you guys will be averaging the solar system’s rainfall !
MDB report says
“Murray system inflows for the three years ending in March were 5,160 GL, or 46 % of the previous three year minimum of 11,300 GL in 1943 to 1946. The persistence and severity of this drought, particularly over the past three years, is unprecedented.”
Figure 2 mate !
My first comment was that the MDB is a big place ! A number of climate zones.
http://www.bom.gov.au/climate/current/statements/scs16.pdf
Figure 3 Pikey – you can’t DENY IT ! 13 years in the making and still going despite PDO change and La Nina …
Your response is typical of the sand-papering denialist. Hence we just fucking laugh at you guys papering over cracks !
kasphar – will agree Federation Drought was more widespread – but from SW WA to the lower MDB – the rainfall over a long period is gone. 12-13 years ?!
kasphar – also the river won’t run dry due to numerous dams and weirs. Animals don’t die like they used to – transport, communications and experience !
Luke has run this official “low inflow” scam on this blog before. And each time he has sidestepped the fact that very large tracts of the upper Murray catchment were burnt out in 2003 and the resulting vigorous regrowth has very seriously diminished catchment water yield.
The MDB Mafia have consistently failed to properly account for changes in vegetation within the catchment. They persist with the totally dishonest portrayal of current post clearing flows as being equivalent to the natural pre-settlement flows. The senior execs of MDBC went out of their way to discourage the 2004 house of reps inquiry from considering the increased yield that was produced by clearing so they could continue to claim that current irrigation allocations were unsustainable.
Yet, the work of Zhang and Vertessy et al make it very clear that the pre-clearing normal flow for the entire basin was only 16,000 Gl with an 8,000Gl increase from clearing activities. And after deducting irrigation extractions of 11,000Gl the current outflow is still 13,000Gl. Add back the SA allocations which still flow the full length of the river system and the reality is that outflows are only slightly down on pre-settlement levels.
But in recent years the area of native regrowth has expanded considerably, by at least 14 million ha in NSW and the broadscale regrowth from the 2003/6 fires, mostly on national park tenure, now constitute a major new, and unapproved, source of water extraction. The venal scum that Luke spends so much time covering for on this blog are perfectly aware of the impact of their management policies on system flows but they choose to remain silent to further their objective of depopulating the entire basin.
The MDB Depopulation Mafia are proven experts in misleading by way of half truths and partial facts like these sleazy inflow stats. On ya bike, Luke, make some room here for honourable men and women.
Love it when the waddler tries the big ram raid.
MDB Depopulation Mafia – well jeez mate you’d better stop living the high life with Foxtel in the burbs and get on down to Come By Chance. You hate the metroscum – so what’s your excuse. You should be in the middle of the MDB. Be handy if you needed to whip on down to Goolwa to punch out a few locals wouldn’t it?
Again you should work in the butcher shop with the little finger on the scales. You’ve skipped from the Murray to the whole MDB hoping the readers didn’t notice. Hands off the scales mate.
And you’re bluffing your arse off – tell us how they do the inflow calculations? Come on – you don’t even know ya big lair? The calcs are fine – you’re not not.
As for the fires – ho hum. Check the rainfall maps I have cited above. No rain is no rain mate. Sort of basic isn’t it.
In any case there would be more trees at the turn of the century 1900s – less land cleared – more trees – more suck – but you haven’t added that in – so we need to increase the earlier drought inflows for that. giggle – you haven’t a clue.
And there’s never been any catchment fires before? Yea sure. Funny how they seem to happen in these big droughts? Part of the landscape dude.
Anyway – you haven’t got time to be here. You’ll have to whip down to the MDB and stop the population exodus.
As I keep pointing out, there were lower rainfall figures between the 1900-1908 then 2000-2008, both Aust-wide and MDB area.
What else can I say?
Good on you Kasphar, the mass delusion about rain and drought in this country runs so deep, facts need repeating. The 2002 drought was only ever the Great West Queensland Drought of 2002 see my analysis of BoM high quality rain stations.
http://www.warwickhughes.com/2002/
Lots more articles about rain – drought at.
http://www.warwickhughes.com/blog/?cat=5
Pity we’re not talking about Australia wide eh? As usual denialists love to deliberately miss the point.
Regrowth uses more water than old growth, eco-gimp. And the reason this recent post fire regrowth has a bigger impact on water yield is that this lot cannot be recleared or thinned as was the case in the past. Remember the clearing bans, boy wonder? All the ecological chooks are home to roost and all our little bimbocrat mate can do is crank out the old undergrad sneer.
And you seem to think the term “metroscum” refers to all metropolitan dwellers. Nope, just the sad plodders who believe what the ABC and the Courier Mail tells them. The ones who send a hundred bucks to greenpimp each year so they don’t feel guilty about their two SUV’s that have never seen a dirt road. The ones who think they have been real clever by buying their water in the 12 bottle “economy pack”.
Pfft – You have no calculations on any of the relativities x areas – and are simply pulling numbers sans bum.
Still waiting for your explanation of the how the inflows are calculated. You don’t know do you? But happy to put the boot in.
Nar you hate metrodwellers – you just wreak of metro abuse – turn off the Foxtel – eschew the shopping malls – get down to the indulgent hobby farm and tend the prickles.
Is that a touch of land envy we can detect in our treeless, landless eco-drone? He thinks he could do a better job at land management but will never get to find out because he is just another ‘poh white campus trash’.
Warwick
You are quite right in one of your links that you state that the BOM have the data to correct many of the fallacious claims made
about drought and floods by providing the media with the facts. But they don’t and I’m not sure why.
Obviously we wouldn’t be wasting our time looking up difficult to find data if the truth, from a reliable source, can be accessed.
Your graph at ‘The 2002 drought in Australia, growth of a myth’ is the type of graph that needs to be known about.
Has it been updated?
If all the money which has been wasted on a non-existant ‘AGW/CC’, had been spent instead on things like the ‘Bradfield Scheme’ then presumably the Mighty Murray wouldn’t be in the state it is now?
What this meaningless graph doesn’t show is which month the rain falls, in the Murray region if all the rain falls in the summer it is useless, worse than useless most of the time because crops and pasture don’t grow in summer only weeds. we need rain in autumn, winter and spring.
We haven’t had an autumn break for 15 yrs, we rarely get enough in winter and spring has become very very dodgy. You might also note that the period 35-45 had unders and overs, from 2000 on its all under and the previous years when it was over I bet that rain fell mostly in summer
If you want to fool somebody use a graph, that is a well known fact in the field of statistics and probability, in fact whole books have been written on this subject, it all depends on the presentation, and this one omits the most relevant information, and is therefore useless and a rather suspect was formulated for a different purpose that this blogger has used it for.
To base ones argument on one graph is an exercise in fooling fools.