Errors in global precipitation measurement

Mother Jones news has an “alarming” article called “Our Coming Mega-Drought” in which they say “…virtually all of the world except for China and Russia will experience increased drought by 2030 and severe drought by 2060” and they cite these computer model maps at left.

Yes, it looks pretty bad. But the thing about models, is that they are very sensitive to starting conditions, and like we’ve learned with temperature measurement errors worldwide, so are there errors with precipitation measurement. Rain gauges are easily influenced by wind, and wind eddies. So things like buildings, shrubbery, trees, and station moves can all have an impact. Pierre Gosselin at No Tricks Zone has a good summary of issue related to precipitation measurement which I present below.

======================================================

Huge Global Precipitation Deficits Due To Woefully Inaccurate Measurement Techniques!

By P Gosselin on 24. Oktober 2010


NOAA 8 inch rain gage. Source: http://www.crh.noaa.gov/iwx/?n=coop_station 

German Weather Service meteorologist Christoph Hartmann writes what I think is a surprising essay on measuring precipitation, and the errors in doing so. Indeed Hartmann says precipitation may be understated by up to 50%, or much more at some locations.

As Hartmann explains, measuring precipitation is by no means an exact science, and results have to be taken with a lump of salt.

There are many sources of errors, and in his essay here he looks at just two main sources: wind and instrumentation.

But first, let’s take a look at how precipitation is measured. In his previous essay he described two types of precipitation measuring gages. In Germany precipitation is measured with the unit of liters/m², e.g. 25.4 liters is an inch of rain.

Two methods of measuring precipitation

Hartman explains that precipitation is generally measured by a rain gage with a known opening area, for example 200 cm² in Germany, which is positioned 1 meter above the ground surface. The gage funnel catches the precipitation and leads it to either

1) a graduated measuring tube or a
2) an optical drop counter

Optical rain gage (drop counting). Source: atmos.washington.edu 

With the measuring tube system, the tube is graduated and the amount of precipitation can be simply read off. With the optical rain gage (drop counter), the amount of precipitation is derived from the number of drops. If the precipitation is snow or ice, then the measuring tube or optical gage are brought inside and the captured precipitation is melted and measured.

Wind and errors up to 400%

Hartmann explains that the biggest sources of error are wind-related. This is easily seen when measuring snowfall. Just before a snowflake falls into the gage, air turbulence sucks it back out tosses it overboard. Just taking a look around after a blizzard, it’s easy to imagine how difficult it is to measure snowfall. Places exposed to wind are barren, while other places are covered by meter-deep snowdrifts. How much snow really fell?

Hartmann says measurement errors of up 400% can occur over time when measuring powdery snowfall in alpine, polar or windy areas.

One way to reduce error is to place the instrument in a wind-protected area. By measuring the wind speed, it is then possible to adjust precipitation measurements. But Hartmann writes:

Wind effects lead to an under-estimation of the actual fallen precipitation. The level of deviation depends on the speed of the wind and the type of precipitation.

Because wind speeds are factored into precipitation measurements, climatological precipitation trends without taking changes in wind speeds into account should always be deduced very carefully.

The second problem encountered arise from the two above described measurement instruments, especially with the optical rain gage, writes Hartmann. With frozen precipitation, the gages are heated up in order to melt the precipitation. But this involves evaporation. And under torrential rains, the optical gage becomes much less accurate. The result, writes Hartmann:

Under equal precipitation amounts, the optical gage measures less precipitation than the measuring tube, both in summer and in winter.

So if two different stations use different instruments, them they will show different precipitation amounts even when the actual precipitation is the same. In summary, Hartmann writes his stunning conclusion:

In total these two sources of errors lead to a precipitation deficit of 5 to 15% for liquid precipitation, and between 20 and 50% for solid [frozen] precipitation. In very windy locations, the deficits are substantially more.

Because instruments measure less precipitation than what actually falls, it means we have a worldwide precipitation deficit solely because of the measurement method.

What does it all mean? Are many of the reported droughts solely the product of faulty readings? And we all thought that the network of temperature measurement stations was a mess. This is a huge open floodgate to potential climatological data manipulation and bogus assertions. See here for example: motherjones – the coming mega-drought (h/t NTZ reader DirkH).

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70 Responses to Errors in global precipitation measurement

  1. Tim says:

    A warmer world is a wetter world so lets generate some more water vapor (you know that REAL GHG!). A lot more CO2 will probably be ineffective in warming the world but it won’t hurt either as plants can use it.

  2. R. de Haan says:

    Messages of doom, disaster and downfall is all they can produce.
    Is there no notion that their models are crap?
    Don’t they know how stupid it is to make any long term prediction about our weather or climate?
    This is tiresome to say at least.

  3. tone says:

    My backyard measurements (2 gauges- drip counter and graduated measuring tube) are sometimes way out from the nearby airbase rain fall measurements (6km distant).
    Rain patterns, like thunderstorms, upset a region’s rain measurements.
    So how correct really are official rain recordings in catchment areas?
    My own measurements also show over thirteen years averaged rainfall by the month is decreasing, and also a three year cycle (using excel “19 moving average” – graph 2 at http://tonyf.customer.netspace.net.au/weather&rainfall/rainfall_since_1999.htm)

  4. DireWolf says:

    I seem to remember a recent WUWT blog where the Australian weather service adjusted the historical precipitation chart down. http://wattsupwiththat.com/2010/10/15/bom-disappears-rainfall-data-no-trend-becomes-downtrend/ I suspect intentional human error may be another leading factor in missing precipitation.

  5. Douglas DC says:

    Mother Jones trying to replace Nature? National Geographic?Weekly World News?
    What next-”Nostradamus’ predictions given to Bat Boy?” sorry if I sound a bit cynical.
    I recall they were on the “next Ice Age ” bandwagon….

  6. Jantar says:

    Unfirtunately I don’t read German, so can’t tell if the point I’m about to make was covered or not.

    There is another very common type of rain guage that is mentioned in this post. That is the tipping bucket rain gauge. All stations on our network (located in South Island New Zealand) use the tipping bucket type. I believe that they are subject to the same types of errors discussed here, but also to another error that overstates the rainfall in some circumstances.

    I have installed a cheap chinese made weather station at home, just for my own interest, and happened to notice a strange situation recently. We were experiencing very strong pre frontal winds with gusts exceeding 70 kmh. It hadn’t started to rain yet, but the rain guage started showing readings. I went out to the weather station to see what was happening, and discovered that at certain wind speeds the rain gauge would vibrate and operate the tipping bucket. Thus rain was being recorded when none was actually falling. It may also explain why our remote weather stations at work sometimes show rain in the prefrontal conditions earlier than we were expecting.

  7. rbateman says:

    Or, in the case of a local rain guage, it was broken most of the year while funds were not available to fix it.
    In another case, it was not properly supported by the computer controls, so it would fill up because the automatic dump mechanism didn’t work.

  8. DirkH says:

    The motherjones H/T must go to thegoodlocust; i found it in Tips&Notes and posted it in Pierre’s blog:
    “thegoodlocust says:
    October 24, 2010 at 9:34 am
    Here is an amusingly idiotic article from Mother Jones:[...]”

    And it’s really amusing; the guy starts rather good, even identifies the study as a modeling study, but ends with “This will happen in the next 20 years if we don’t act now”, completely forgetting that it’s all computer conjecture. People are so easily fooled when a computer is involved. I should exploit that more myself…

  9. Phil R says:

    Mother Jones news has an “alarming” article called “Our Coming Mega-Drought” in which they say “…virtually all of the world except for China and Russia will experience increased drought by 2030 and severe drought by 2060”

    Hmm… Mother Jones news and the only two countries that won’t experience increased drought are or were both communist….

  10. Richard P says:

    I participate in the CoCoRaHS rain Gauge Network. While working on my Master’s degree I did a short study on gauge accuracy and precision. There are 4″ dia gauges with a graduated cylinder for the reading. My results mirrored the links above for high winds. Much of the under reporting I saw was due to splash out of the rain hitting the funnel. This was confirmed with a high speed video camera. Given similar measuring methods the precision was +/- 1%, however if I removed the funnel and just used the 4″ dia tube during high wind situations, the difference was 20% to 80% more collection in the open tube.

    Like everything in science, you must know the limits of your measurement system before making assessments no less model inputs for the data.

  11. Neo says:

    I have this Charlie Brown feeling of …
    AAAAARgh !! Can’t anybody do this stuff right ?

  12. WillR says:

    Aw sheesh. Bring Back Al Gore and his floods… I am sure we can cope with that a lot easier. It looks like we have a choice — nay a cornucopia of disasters from which to chose — so we may as well choose those that favor us… Even the reverse revolving hurricanes would likely be better…

  13. DirkH says:

    Phil R says:
    October 24, 2010 at 6:18 pm
    “Hmm… Mother Jones news and the only two countries that won’t experience increased drought are or were both communist….”

    You mean communism helps? That’s good news. The social democrats, Greens and Communists in Germany could form the next government here in Germany if elections were held now. So we should be save from drought.

    Every dark cloud has a silver lining…

  14. Ron House says:

    But, but, but… There was a research result reported here a few months back that we would all die of heat stroke because the temps would be high and we would be unable to cool by sweating due to 100% humidity. At 100% humidity the merest shade of cooling (e.g. when the sun goes down) and it is raining. So how do droughts happen? It couldn’t be that the alarmists are making up whatever BS they think will ‘sell’, could it? Nah!

  15. steven says:

    CCSP, 2008: Reanalysis of Historical Climate Data for Key Atmospheric Features

    “It is unlikely that a systematic change
    has occurred in either the frequency or
    area coverage of severe drought over the
    contiguous United States from the midtwentieth
    century to the present.”

  16. John Kehr says:

    This type of predication is garbage. Even without the issues of initial conditions based on measurement systems the science is flawed. The “proposed” warming will dramatically increase the amount of evaporation from the oceans. While patterns could shift if global warming really did happen, the amount of total rainfall would increase globally.

    A quick look at the map shows that the expectation is that the jet streams would stop functioning and somehow the Gulf of Mexico would stop sending vast amount of humid air into the central United States. It appears that he used every scenario that causes drought and simply amplified them.

    John Kehr
    The Inconvenient Skeptic

  17. Richard Sharpe says:

    Ron House says on October 24, 2010 at 6:37 pm

    But, but, but… There was a research result reported here a few months back that we would all die of heat stroke because the temps would be high and we would be unable to cool by sweating due to 100% humidity. At 100% humidity the merest shade of cooling (e.g. when the sun goes down) and it is raining. So how do droughts happen? It couldn’t be that the alarmists are making up whatever BS they think will ‘sell’, could it? Nah!

    Well, what will happen is that the moisture will precipitate out but it will evaporate again before hitting the ground, so there will be more droughts while there will also be an acceleration of the hydrological system so that there is tons more moisture in the atmosphere.

    Simple, isn’t it?

  18. Dave Springer says:

    It’s worse than we thought. Climate change is now laws of physics change.

    Do these idiots really expect anyone to believe that the water cycle is going to cease working virtually all over the globe? Oh wait. They published it in Mother Jones news. Of course they’ll believe it.

  19. Jimbo says:

    CERTAINTIES?

    “…virtually all of the world except for China and Russia will experience increased drought by 2030 and severe drought by 2060″

    UNCERTAINTIES?

    [IPCC - 2007]
    Climate Change 2007: Working Group I: The Physical Science Basis
    3.3 Changes in Surface Climate: Precipitation, Drought and Surface Hydrology
    In situ measurements are especially affected by wind effects on the gauge catch, particularly for snow but also for light rain. For remotely sensed measurements (radar and space-based), the greatest problems are that only measurements of instantaneous rate can be made, together with uncertainties in algorithms for converting radiometric measurements (radar, microwave, infrared) into precipitation rates at the surface. Because of measurement problems, and because most historical in situ-based precipitation measurements are taken on land leaving the majority of the global surface area under-sampled, it is useful to examine the consistency of changes in a variety of complementary moisture variables.
    http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch3s3-3.html

    Then there is this:

    “…..evidence indicates that summer soil moisture content has increased during the last several decades at almost all sites having long-term records in the Global Soil Moisture Data Bank (Robock et al., 2000).”
    Journal of Hydrology Volume 319, Issues 1-4, 15 March 2006
    more…

    In the meantime the Sahel is greening in a co2 enhanced, warming world.

  20. Robert of Texas says:

    As someone noted, rain is a very local phenomenon. I have seen it raining heavily a mile from my house, but upon reaching my driveway find my yard still parched and dry. So it would seem reasonable at least where I live that the variance of any one station would be so ridiculously high as to be unusable for trend analysis. Maybe where you have monsoons and large area rainfall it would work as the larger rain pattern would be (I speculate) more constant.

    It seems to me that lake levels, dam water-flow, and river flow information would be more useful (if kept and accurrate enough) for determining rainfall trends related to climate. As a lake will tend to accumlate water from the same area of land over time it seems it would be a good proxy. Surely communities keep track of how much water they pull from lakes and rivers for water treatment. This would be an interesting study for someone with the time.

  21. Ryan Maue says:

    As it happens, this southern U.S. drought is probably not caused by global warming — not mostly, anyway. Like most droughts until now, its primary cause is natural climate oscillations (this year’s La Niña) and bad luck (no hurricanes so far this season).

    This equivocation in the article seems to blow up whatever predictions are made afterward…

    And no hurricanes to Mother Jones is: “bad luck”. WTF?

    REPLY: I was going to comment on that one, but figured I’d leave it to you if you want to expound on it. – Anthony

  22. Smokey says:

    Phil R says:

    “Hmm… Mother Jones news and the only two countries that won’t experience increased drought are or were both communist…”

    Mother Jones is seriously wrong. China has been experiencing major droughts since before AGW was a twinkle in Svante Arrhenius’ daddy’s eye: click

    The Gobi Desert is only about 40 km from Beijing, and it is heading their way. They’re trying to stop it. Wishful thinking, just like Mother Jones’ belief that deserts are caused by “AGW.”

  23. RiHo08 says:

    My local rain gauge is the ground water level in the 5 interconnected (via gravel veins) gravel pits in our local wetlands that have no discernable outlet. My calibration is where trees that have grown in the recent but distant past lower water table and whether or not they are covered, and if so, for how long: ie, have they survived being water logged for the past year. Four inch diameter poplar and cottonwood trees have died over the past year from being submerged for more than a year. So, in my estimation, the ground water level has risen more than 2 feet. Judging by the 6 foot extent of the shoreline brown of the surrounding grass, it seems that the high water from this last winter and spring has receded to a level 2 feet above previous “normal” levels. No recent drought in my immediate neck of the woods. Last weekend, our Fall Color Tour took us to a Northern region identified October 19th as moderate drought region on the usual NOAA maps. We tramped through rivers, streams, bogs, and lakes with water upto high water marks and were briskly flowing. Campfire wood we purchased was wet and we had a dickens of a time getting it started. Now this is not a global assessment, and admittedly very regional, but the drought maps and our direct experience over the same mapped areas was markedly different. I wonder how much time drought people spend tramping through the woods? fishing the streams? eyeballing rather than relying on some remote rain gauge which may or may not be accurate? I had better close my bedroom window, I hear thunder rumbling and it is getting closer.

  24. johnmcguire says:

    I use the five gallon bucket method and probably get as good accuracy. I used to use my wheelbarrow tell the bottom rotted out.

  25. Olen says:

    Is Mother Jones available for Vegas. They sure know how to make a safe bet. Picking 2060 is brilliant.

  26. Jimbo says:

    Douglas DC says:
    October 24, 2010 at 6:00 pm
    ………..
    I recall they were on the “next Ice Age ” bandwagon….

    They have said quite a few alarmist things in the past.
    See “The Thirteenth Tipping Point” [2006].
    http://motherjones.com/environment/2006/11/thirteenth-tipping-point
    http://motherjones.com/environment/2006/11/thirteenth-tipping-point?page=2
    http://motherjones.com/environment/2006/11/thirteenth-tipping-point?page=3

  27. Richard says:

    Rainfall measurements over even small distances is quite variable, even when using exactly the same type of equipment.

    When doing a trial to determine the feasibility of using treated Kraft pulp mill wastewater for irrigating pastureland, it was essential to know the natural rainfall. The field used was about 150x250m and used 6 rain gauges, one in the centre of the shorter sides and 2 on each of the longer. The closest hills would have been about a Km away and the nearest trees, young pines ~5m tall, about 100m away. The gauges could vary by more than a factor of 2, and there was no constant pattern. A low gauge one time could be the high gauge the next and, from memory, no two gauges ever gave the same reading except when rainfall was non-existent or very low.

    Which rain gauge gave the correct reading? Who knows? If 6 gauges within 250m of each other cannot agree then how can any data collected from rain gauges be said to have any degree of either accuracy or precision? The data is possibly accurate to within an order of magnitude but that is all.

  28. Jimbo says:

    I just don’t get this drought issue. Global warming will lead to more water vapour in the atmosphere. Where will it all go? To Russia, China, the Oceans or outer space?

    This is a total crock based on a money scam backed up with damned LIES.

  29. Has a published computer model finding ever shown that the future will be better? That no additional funding is needed to study how to forestall doom? Ever? Just once?

    Just asking…

  30. davidmhoffer says:

    I read the mother goose story. Jones. I meant Jones. It was something about the sky is falling. No… not falling. Rain. Yup, that was it, rain not falling. Anyway, they went to see the king… No, I’m mixed up again. They went to pick the king. Not the king, the king’s court. Anyway, some of them got bonked on the head by Acorns which is how they knew the sky… no the rain wasn’t falling. No it was falling now, but soon it wouldn’t be. Really complicated the story, sorry. Anyway, it turned out that only one of them had been bonked on the head by Acorns, the rest were already bonkers, but that isn’t the point, the point is that the rain wasn’t going to fall anymore. But picking a king’s court is no easy task and some of the people who are trying to become courtiers don’t seem worried about the rain not falling because they drink a lot of Tea. Drinking Tea makes you stupid, or maybe being stupid makes you drink Tea, I forget, but the Tea makes you go pee which is like water falling. Way better than Cool-Aid which is fatal sometimes but usually just makes you bonkers. Hallucinagenic I think they call it, if you drink the Cool-Aid it makes you think the sky is falling. Or not falling. No, it was the rain. Rain not falling. If you drink the Tea, the rain won’t fall and we’ll all die. That was it. So all these folks who are bonkers want the king’s courtiers to be bonkers too which is why they started saying that if you drink Tea we’ll all die and proved it with some colorful pictures. Not the kind kids make with crayons, these are much better. They are made of tiny dots and if you just believe in them hard enough, POOF! they become proof. The king himself must have taken a few dots… I mean believed hard enough because he is really upset that some of his new courtiers might be Tea drinkers and who knows which of his plans they will pee on? Rumour is he is angry, in fact livid, the blood pressure has turned his face red. Which is really odd because lot’s of people said he was black but they were only half right, so now that he has turned red, what color is he? The Tea drinkers are adamant that this is the You ESS of Aye where color doesn’t matter but if you put a bit of whiskey in with their Tea they’ll tell you after a couple of cups they figure that was his real color in the first place. But I’m off on a tangent, sorry. Oh yes, the Cool-Aid drinking Acorn bonked little chickens are all afraid the rain won’t fall so they don’t want anyone to pick courtiers who think the rain will fall because they’ll help make the rain not fall by making it warmer which causes water vapour to leap out of the oceans in vast quantities into the sky from which it then doesn’t fall. The dots in the picture prove it if you just believe hard enough. Turns out Daffy Duck was wrong, gravity doesn’t work after all. Well of course he wasn’t made of little dots, not at first, I think they used pencil crayons, so maybe that’s the reason. Point being that I thought the Acorns had gone away, but there still seem to be a lot of people who have been bonked and want all the rest of us to be bonked as well. Bunch of bonkers. If they get their way we’ll all be bonked. Boinked. We’ll all be boinked. And the sky will fall anyway. I mean rain. I mean rainfall. Been drinking beer as I type this and it seems to be wanting to come out the other end so gotta sign off and run go… let some rain fall. I’d say what color but color doesn’t matter in the You ESS of Aye.

    Oh wait, I’m in Canada. Dang. Can’t vote. Not much rain here but got snow, lotsa snow. White snow. Well some that’s yellow. Mostly white. Is that why your king doesn’t like us?

    [REPLY - May Foxey Loxey eat all your Chicken Licken ~ Evan]

  31. DesertYote says:

    The noise machine is setting up the ground work for what they anticipate might be a cooling trend. If it global temps cool, then they can start talking about drought. Warm-Wet or Cool-Dry, they will always have something to talk about, and its mans fault!

  32. rbateman says:

    If the 2060-2069 model is correct for the far North, then with that much precipitation the Ice Sheet is advancing. Followed up with Low Pressure cells that duck south of the High Pressure cells that like to park over Ice Sheets. The present deserts would then turn green with the forced weather patterns due to advancing Ice Sheets, and the model is junked.

  33. crosspatch says:

    Actually, calling for “megadrought” is a pretty good call as the past 500 years have been one of the wettest periods in the past several thousand years. So a return to something a little closer to average for the past, oh, 5000 years or so would be a “megadrought” relative to what we perceive as “normal”. It hasn’t been “normal” since Europeans arrived in the Great Basin and far West.

  34. Pat Moffitt says:

    Wait a minute!!! Define drought. The Mother Jones article never says what type of drought. One can have a hydrologic drought- like Lake Meade where a new allocation draws off a million acre-feet/yr more water than is released to it from Lake Powell. We can have a Meteorological drought which is tied to a decline in precipitation and finally an agricultural drought associated with soil moisture, aridity and a particular crops needs.

    Drought is a complex subject and often not linked in any meaningful way to climate or precipitation.

    Consider the Colorado River drought- in 1903 it delivered some 22,000 ft3/s of water to the head of it’s estuary. By 1934 water irrigation diversions were siphoning 80% of the river’s flows. By the 1950s the Colorado no longer reached the sea drying up its estuary. In 1996 0, nada, zip, zilch zero flow was recorded at the point the Colorado River enters Mexico. I listen in frustration to the media reports on climate change causing a drier western US– the cynic in me asks drier than what -ZERO? And this problem is not going to be fixed by windmills.

    Demand precise definition as a first step in any problem discussion.

  35. Robin Kool says:

    With all other things equal, a warmer atmosphere should mean more evaporation of water, wherever there is water to evaporate: oceans, lakes, rivers, swamps and anyplace that is wet because it has just rained.
    Vegetation also evaporates more water when it is warmer.

    Warmer air ->more evaporation – more rain.
    Or: CO2 driven global warming ->warmer air -> a larger volume of water constantly being evaporated and raining out.

    On the other hand:
    If global warming is really going to happen mostly on the North and South Poles and at night, as I have read, then the difference in temperatures between the poles and the equator (which is what drives the wind globally – right?) and between day and night, will diminish, resulting in less wind.
    Less wind -> less evaporation – less rain.

    When there is no wind, all that warm air does very little evaporating. Air is a very bad conductor of heat, as anybody with double glazing knows.
    When there is wind, warmer air gives more evaporation.

  36. B says:

    Depends if the weather is fully controlled by then. You can see it is already heavily modified.

  37. AusieDan says:

    Hey but in my country
    Hot means dry
    and cold means wet.
    What on earth am I missing?

  38. davidmhoffer says:

    [REPLY - May Foxey Loxey eat all your Chicken Licken ~ Evan]

    I’m waiting for Foxey Loxey to make her move. Foxey wanted to be king but settled for being a courtier and now her job seems to be to go to foreign places on the orders of the king and uhm… rain on them. Unless they’re tyrants of course and then she has to su- be nice to them. I think she still wants to be the king though, and she just might resign after the Tea party has its party to celebrate all the new courtiers and challenge the king for his right to run to be king. Her husband Bill said she would be a queen not a king, but she told him point blank she had a bigger pair than he did and would make a better king which the tea partiers got a chuckle out of, but they want Monica’s number to see if it is true.

  39. freersben says:

    mqbec Google ydd pxpbb

  40. tom s says:

    Just playing devils advocate here, but won’t they just say that ‘it’s not the absolute value, but the change over time’. So, even though your measuring device measures incorrectly in absolute terms, you will still be able to gleen a rate of change over time. However, from what precip studies I have seen based on observed data there is not much of a longterm trend noted, in spite of supposed warming of the smashingly significant 0.6C this past century.

    I take longterm model predictions with a grain of salt and in the NCAR study that I read they put a disclaimer at the bottom of the press release that says this;

    “Future drought. These four maps illustrate the potential for future drought worldwide over the decades indicated, based on current projections of future greenhouse gas emissions. These maps are not intended as forecasts, since the actual course of projected greenhouse gas emissions as well as natural climate variations could alter the drought patterns.”

    SO WHAT THE HECK IS THE PURPOSE? Why share this with the public? It has no predictive value?….Yes….soooo….then…..huh? Yet the alarmists take it as signed sealed delivered I’m yours!

    (shrugs shoulders)

  41. PM says:

    Slightly off topic. NASA has been reseraching rain formation in Finland, it seems that the climate models are somewhat lacking.

    http://www.hs.fi/kotimaa/artikkeli/Nasa+haki+Suomesta+tietoa+tihkusateesta/1135261134496

    Google translate gives the general idea of the news

  42. mosomoso says:

    Recently, NSW emerged from its long drought. Just as a particularly lethal and expensive quango called the Murray-Darling Basin Authority was publishing its findings that water quotas would have to be drastically and permanently cut, our great western rivers went into flood.

    No probs. The Authority still thinks it’s a great idea to wipe out irrigation agriculture and the towns that depend on it. (Large-scale harvesting and damming of water is now, of course, a non-topic.) I’m sure you’re familiar with the terminology of these guys: “environmental flows”, “life of rivers”, “green jobs”, “sustainability”, “long term climate change”. (To be completely fair, those environmental flows of black, de-oxygenated sludge are proving deadly to river life. So it’s not just humans and livestock that are targetted by our green theorists.)

    Should eastern Australia return to its mid-century warmer/cooler pattern, there will be plenty of flooding for our model-builders and catastrophists to invoke as proof of Gaia’s wrath. It will be a brief if difficult transition for the poor loves, but, believe me, a good sized Aussie flood will make for better photo-ops than stranded polar bears and groaning glaciers.

    Moreover, since you can make a model do anything (except predict or portray accurately), I see a shift in the PDO as a chance for Mann and Hansen to re-invigorate their careers. That whole warming gig is so last century anway.

  43. mosomoso says:

    “…its mid-century warmer/cooler pattern…”

    Whoops. I did mean to say wetter/cooler pattern. Do not adjust your models.

  44. John Trigge says:

    As the global average temperature has risen since 1900, I would expect to see more droughts already.

    However, looking at the Australian BOM data (http://reg.bom.gov.au/cgi-bin/silo/reg/cli_chg/timeseries.cgi?variable=rain&region=aus&season=0112) it appears that Australia’s rainfall has been INCREASING since 1900. Australia, being one of the driest countries, should be getting drier according to the Mother jones’ maps.

    Re:
    Jantar says:
    October 24, 2010 at 6:02 pm

    I also have one of these (or similar) which uses a balance arm that registers 0.3mm for each movement. We recently had an earthquake and my rain data showed 150mm without any rain falling.

  45. Christopher Hanley says:

    “Australia is the harbinger of change” Tim Flannery climate alarmist extraordinaire (2009).

    In April last year, Julie Cart for the L.A. Times wrote a hyperbolic piece on the Australian drought:
    ‘…the worst drought in more than a century [not so]….prolonged drought and deadly bush fires in the south, monsoon flooding and mosquito-borne fevers in the north, widespread wildlife decline, economic collapse in agriculture and killer heat waves [none of it unprecedented or unpredictable and grossly exaggerated]…… the “accelerated climate crisis” that global warming models have forecast…’:
    http://articles.latimes.com/2009/apr/09/world/fg-climate-change-australia9
    Well the models didn’t predict the downpours (particularly in the Murray-Darling basin) of the last few months:
    http://www.bom.gov.au/jsp/awap/rain/index.jsp?colour=colour&time=latest&step=0&map=anomaly&period=3month&area=nat
    (30 year average from 1961 to 1990)

    That has been the nature of the Australian climate since European settlement and no doubt from well before:
    http://www.bom.gov.au/cgi-bin/climate/change/timeseries.cgi?graph=rranom&area=aus&season=0112&ave_yr=15

    The overall global pattern looks similar, with a slight positive trend — some areas receiving more, some less:
    http://www.bom.gov.au/cgi-bin/climate/change/global/timeseries.cgi?graph=global_r&region=global&season=0112&ave_yr=15

    Where is the evidence that it has ever been any different?

  46. david says:

    Yet more numbers, ywt more undefined error bars. The hubris of climate scientist is quite amazing. Just as computers were suppose to cut down on the need to print, but instead made thousands of charts and all writing much easier to produce which lead to much greater printer use, so computers and computer models take thousands of POORLY known and disparately created observations, and numerous POORLY understood physical processes, and arrive at CERTAIN prophecies of global disaster while demanding trillions of dollars NOW, which all sides admit will have NO EFFECT without China and India aboard.

  47. Dave Wendt says:

    Has anyone thought to post this over at RC? If it was at all believable, it would seem to put a pretty good dent in the whole CO2 driven warming – reinforcing H2O feedback meme. Do you think the lads on the Team could resist the temptation to push another potential catastrophe or are they actually bright enough to realize that by doing so they would be stepping on their own tallywackers?

  48. Norm in Calgary says:

    Yabut, wouldn’t the same error apply in the past so it all cancels out and there really is less precipitation now. Wasn’t it windy during storms from the past, or did they use the string holding the rock hanging from the tree branch to check rainfall?

  49. Ecotretas says:

    One of the biggest rainfalls in Portugal last month didn’t even get measured, and then I also detected that the public Institute (INAG) measurements were being given in mm, instead of cm, despite comparisons to nearby stations indicating 10x more rain. Details (in Portuguese) available at http://ecotretas.blogspot.com/search/label/seca

    Ecotretas

  50. JohnH says:

    Meanwhile back to UHI, center of glasgow scotland 10.25pm last night 6 Centigrade, 10 mins later 6 miles out 1 degree centigrade. 35 miles later zero degrees C.

  51. Alex the skeptic says:

    We always had shamans telling us that the world is gonna end in the year 62, 458 1002, 1704, 1922, 2000, 2012. Only in the old days they used to be laughed at and pilloried. These days they get billions in grant money from our taxes.

    Here in the middle of the Mediterranean sea, on the tiny island of Malta, we are having one of the wettest Octobers ever and already have half the annual rainfall average, measured between 1st September and 31st August. I have been following the weather here and now globally, since I was born. My father, besides being a school teacher, also kept the weather records of our town for the Maltese met office until he retired in 1981 and I used to help him read the instruments and manually work out the maths. I can easily say that rain is as abundant and as scarce as it has been for the last 50 years, some years its good, others its bad. The year before we had 28 inches of rain, last year it was 16 inches while our average is around 20 inches. This year looks like its gonna be a good rainy one.

    Rest assured that everything is normal, so drink that cup of tea and go back to sleep.

  52. mosomoso says:

    John and Christopher. Here’s a genuine Australian climate disaster, one which Tim Flannery could certainly confirm. Imagine what it would have been like further inland!:

    “At 9 a.m., 85 degrees. At noon, 104. Half past twelve, 107½. From one p.m. until 20 minutes past two 108½. At 20 minutes past two, 109. At Sunset, 89. At 11 p.m., 78½. [By a large Thermometer made by Ramsden, and graduated on Fahrenheit's scale.]…

    “But even this heat was judged to be far exceeded in the latter end of the following February, when the north-west wind again set in, and blew with great violence for three days. At Sydney, it fell short by one degree of what I have just recorded: but at Rose Hill, it was allowed, by every person, to surpass all that they had before felt, either there or in any other part of the world. Unluckily they had no thermometer to ascertain its precise height. It must, however, have been intense, from the effects it produced. An immense flight of bats driven before the wind, covered all the trees around the settlement, whence they every moment dropped dead or in a dying state, unable longer to endure the burning state of the atmosphere. Nor did the ‘perroquettes’, though tropical birds, bear it better. The ground was strewn with them in the same condition as the bats.”

    That’s an entry from the journal of Watkin Tench, Captain of Marines. He came out on the First Fleet. Curiously, Tim Flannery is particularly interested in Tench and the early settlement. Go figure.

    The reference is to the Sydney summer of 1790-1791.

  53. Alexander K says:

    I measure max and min temp plus precipitation each day in my suburban back yard in London. Despite said back yard being what should be an example of a UHI-affected site, my recorded max temps are currently around 60% LOWER than the Met Office daily forecast. My recorded min temps are also usually a significant percentage below that forecast. The forecasts seem to pass into history without comment as the met office forecasters never refer to yesterday’s actual figures but move right on to the forecast for the next day. I believe that, while my quite rudimentary equipment may be in slight error, a consistent 60% error is way beyond acceptable in terms of believable forecasting.
    I have come to the conclusion that the actual temperatures are rarely made public until a significant amount of time has elapsed or an unuasual weather event occurs and that the current reality is that the climate in the part of London where I live is much cooler than the general population are being led to believe.

  54. Christopher Hanley says:

    mosomoso (12:23 am), 109°F would have been a bit of a shock I dare say
    http://www.diggerhistory.info/images/diggers/soldier-rum-corps.jpg.
    Just for the record, the maximum temperature ever recorded at Sydney Observatory (commenced 1858) was 45.3°C (114°F) on 14th January 1939 (the atmospheric CO2 concentration then was around 310 ppm)
    http://www.bom.gov.au/climate/averages/tables/cw_066062_All.shtml.
    Hmmm, I’m getting those ‘denier’ ideas http://hidethedecline.eu/media/Northern%20hemisphere%20temperatures/crumat.jpg.

  55. John Marshall says:

    Rainfall measurement is fraught with errors. Due to the localised rainfall problem there is little chance that the maximum rainfall will be measured if at all. Warm fronts produce large area showers which may be caught by the gauge and so the area rainfall can be calculated, provided the total area is known. Summer showers are thundery and very localised and the nearest gauge may not get any rain readings at all. Most rainfall readings will be an underestimate of actual rain that fell.
    Models will produce any future scenario that you want but little of scientific substance.

  56. Alex the skeptic says:

    Richard Sharpe says:
    October 24, 2010 at 6:51 pm
    Well, what will happen is that the moisture will precipitate out but it will evaporate again before hitting the ground, so there will be more droughts while there will also be an acceleration of the hydrological system so that there is tons more moisture in the atmosphere. Simple, isn’t it?
    __________________________________________________________
    Well, the problem with catastrophic climatism is that its proponents think that it is so simple, but it is not. It is very very complicated. That is why there’s this global discussion going on. What’s sure is that more and more scientists are coming out of the woodwork saying that they are skeptical about the very idea that CO2 = global warming and logically, the rest falls flat on its face. Because since AGW rests on one forcing; that an increase in atmospheric CO2 causes global warming, then once this theory is proven wrong, AGW theory collapses, as it has already done, in my opinion. Only it is being given life support by the MSM. politicians and the money-grabbing scientists.

  57. Julian Braggins says:

    I once had a chance to compare an official Australian BoM rain gauge with my own straight sided 2″cylinder sharpened to a knife edge at the orifice to the inside edge graduated with a machinists rule on the inside. Despite the fact that they were within 2 metres of each other, my simple tube registered 20% higher over several months with daily readings.

    I could only conclude that there was some mismatch between the funnel area and the indirectly calibrated tube supplied with the official gauge. other explanations anyone?

    Granted long term trends would not be affected, but only if all the gauges were equally in error.

  58. ROM says:

    One curious old Australian grain farmer’s personal experience.
    Does seasonal rainfall vary much across a paddock?
    Paddock size; 2 kms x 2 kms; ie; 4 sq kms = 400 ha’s = 980 acres.
    No fences. No buildings. No obstructions.
    No trees within a kilometre of the paddock [ exception; neighbour's house yard approx 1/2 km from paddock.]
    Terrain flat as in almost dead flat except for a large area where there is a very gentle fall of less than 3 metres onto another large flat area.
    This particular farming region is renown for it’s flat terrain with the nearest mountain range some 80 kms to the South.[" hill's" to Americans and Europeans. This is Australia, one of the oldest and most eroded continents on Earth where you can cross some 3000 kms from the Great Australian Bight in the south to the Gulf of Carpentaria in the north without getting more than 200 feet above sea level. ]
    Soil type ; very even black cracking clays all over.
    No internal fences or any obstructions, just a big open Australian paddock!
    Crop was wheat all over.

    Late Autumn / Winter / Spring season rainfall is by far the predominant pattern [ mid April to early November is our main rainfall period down here in the SE Australia.]

    13 identical rain gauges gridded across the paddock with the outer ring of gauges placed some 50 metres in from the outside boundary fence to reduce fence effects and other influences.
    Gauges were positioned after the wheat crop was sown in mid May which is our normal sowing window for cereals.
    Gauges were measured and recorded weekly.
    Kept myself and the old dog pretty fit walking and plugging our way in wet soil across that 2 km square paddock of growing wheat to measure and record those 13 gauges.

    By late September it was quite clear from the gauge recordings that about one quarter of the paddock was consistently receiving less rainfall than the rest of the paddock.
    The deficiency amounted to over 15% difference by the time I stopped recording in mid October.
    Another corner, about 10% of the paddock received consistently higher precipitation than the rest of the paddock despite switching gauges around in case there were gauge inconsistencies.

    There was no identifiable explanation or reason for this consistent seasonal variation in rainfall across this very flat terrain and very even paddock.
    As somebody who had farmed that paddock for over some 30 years I had often noticed that where the lower rainfall had been measured in the paddock, it seemed to be consistently less yield over the years than the rest of the paddock area.

    Item 2 ;
    Grain yield and variety research plots located approximately 300 metres directly down wind a 200 metre long cross wind line of 10 metre high open forest Australian Buloke trees, with a total area of 9 ha’s.
    This patch of 9 ha’s of open forest was located directly upwind of the plots in the the prevailing winter westerly winds

    Plots extended another 60 metres down wind so the nearest plots to the tree line were at about 300 metres distance and the furtherest set of plots were at about 360 metres distance from the tree line, all directly down wind in the prevailing winter westerly winds.

    Two identical precision rain gauges were installed, one at the plots nearest the trees [ 300 metres] and one on the furtherest downwind side of the plots [ 360 metres ]
    Terrain again is dead flat with no other obstructions of any type other than that patch of Bulokes, within a couple of kilometres.

    There was a completely consistent difference in readings over some 3 months winter rainfall of some 20% between those two gauges.
    The gauge closest to the trees some 300 metres away gave the lowest readings.
    We measured those gauges as accurately as we could with a variety of methods.
    We swapped those two gauges a number of times but nothing we did changed that consistent difference in rainfall amounts between those two gauges only 60 metres apart.
    To repeat; The terrain was an open dead flat, sown paddock right across to those trees and for at least a kilometre or more around.

    The wind roll over effect from those trees was probably reason for that difference in rainfall amounts and that is the only explanation I can come up with for that remarkably consistent difference in those rainfall readings.

    I believe that a similar rainfall / paddock experiment in Western Australia also found similar unexplainable differences in rainfall patterns that could not be accounted for by any logical explanation.

    As an old Glider pilot with nearly 50 years glider flying plus some power flying , I have flown mountain wave systems and know the effects of airflow around hills and over mountains.
    Twice I have come close to being killed by the roll over of strong winds over a dense line of trees located across and upwind of where I was landing a glider.
    Despite a higher than normal airspeed I simply lost all my airspeed in a couple of seconds, as from 60 knots to zero when I hit the front down draft from the roll over and then a few very, very long seconds later it jumped to over 70 knots in about a second as I hit the backside updraft of that particular roll.
    That line of trees were located some 2 kilometres directly upwind from where I was trying to land.

    I know the turbulence that is generated a kilometre down wind from a steady wind across a hangar complex at a small country airport with one sealed strip, when a light aircraft is low down on approach for landing.

    Even where there seems to be very good locations for weather recording stations, I look at those sites and photos and I can see immediately where serious measurement problems can originate from quite long distances away as in hundreds of metres away from small as well as large obstructions.
    Obstructions and small terrain changes at distances that those with little knowledge or experience on just how our complex atmosphere is constantly changing and moving would discount as not worthy of bothering about.
    Unfortunately the accuracy of the measurements of temperature, rainfall, humidity and temperature can be and are often seriously affected and in nearly every case the effects on rainfall and etc are unknown, unmeasured and are not even ever taken into consideration or recognised as a serious problem for accurate data measurement.

  59. JKrob says:

    “Hartmann says measurement errors of up 400% can occur over time when measuring powdery snowfall in alpine, polar or windy areas.”

    I wonder if that is what is happening in internal Antarctica. They say it is a “desert” with little precipitation. But there have been stories right here on WUWT showing people digging out instruments & having to raise instrument towers to account for snow covering it…all that snow & ice has to come from somewhere – it’s all not just being shuffled around.

    Jeff

  60. Jeremy says:

    speaking of precipitation…

    I live in Southern California.
    Last year was officially the wettest year Southern California has ever had.
    At this time this year we are at: 13.94 ”
    Normal is: 9.92 ”
    Last year at this time was: 5.27 ”

    If I wanted to jump to conclusions, I’d say mother nature is turning So.Cal back into swampland.

  61. Jantar says:
    October 24, 2010 at 6:02 pm

    Unf[o]rtunately I don’t read German, so can’t tell if the point I’m about to make was covered or not.

    There is another very common type of rain guage that is mentioned in this post. That is the tipping bucket rain gauge. ….

    …. We were experiencing very strong pre frontal winds with gusts exceeding 70 kmh. It hadn’t started to rain yet, but the rain guage started showing readings. I went out to the weather station to see what was happening, and discovered that at certain wind speeds the rain gauge would vibrate and operate the tipping bucket. Thus rain was being recorded when none was actually falling. It may also explain why our remote weather stations at work sometimes show rain in the prefrontal conditions earlier than we were expecting.

    The cause of error in measuring rainfall you described has not been mentioned in the article.

    JKrob says:
    October 25, 2010 at 5:27 am

    You discussed the measurement error due to distortions by wind-driven snow. Without a doubt, snowfall measurements can be lower than the amount of snow that actually fell, for all of the reasons discovered and discussed. What was not discussed in the article by Christoph Hartmann is the possibility of more snow fall being measured than actually deposited.

    Our farm is in a flat area in which during the winter arctic-like conditions prevail quite frequently. That means that in some locations in our area it can happen that, when strong winds blow, much snow that fell already weeks prior is picked up by winds and redeposited, so much so that daily snow-plowing is necessary even though no snow had been falling for weeks.

    That sort of drifting does not involve just a bit of snow at ground level, but the snow can be lifted to such heights that the sun is obscured. Such conditions are very common in the Arctic. Those sort of conditions are not accounted for in the explanations of the measurement errors explained by Christoph Hartmann. However, that is hardly surprising, such conditions rarely, if ever, occur in Germany (except perhaps in the mountains, although I am not aware of rain gauges being located on any plains there).

    John Trigge says:
    October 24, 2010 at 11:10 pm

    I also have one of these (or similar) which uses a balance arm that registers 0.3mm for each movement. We recently had an earthquake and my rain data showed 150mm without any rain falling.

    The article by Christoph Hartmann does not mention earthquakes as a cause of error when measuring rain fall. That does not mean that your observation is incorrect.

    A search of the Internet for “precipitation “measurement error” earthquake” produces 1,910 results.

    A search of the Internet for articles on “precipitation “measurement error” wind” produces 6,420 results.

  62. pyromancer76 says:

    Thanks, Anthony. There is nothing “these people” won’t falsify or fraudulently alter for their purposes, it seems. The technology for data gathering must be put through rigorous scrutiny and no one does it quite like you. I also like it when we not only read about “the science” but about “these people”, who funds them, and for what “purposes”.

    As to Tim’s assertion (5:33 pm): “A warmer world is a wetter world so lets generate some more water vapor (you know that REAL GHG!).” Tim, it all depends on where you live when on Earth’s surface. The western U.S. goes into major droughts (according to the research I have seen) during warm periods, e.g., MWP. We do much better re water during the cold times. Is this the same for the west coast of South America? Is this true for Australia (with four oceans)? If I remember correctly the Sahel/Sahara greens during the warm times. So, I think we must differentiate between warm-wet, warm-dry, cold-wet and cold-dry — up to a point. Overall warmer is better, certainly better than advancing glaciers, but tell that to the Anasazi (major droughts 1130-1180 and 1276-1299).

    Therefore, generalizations “should be” corrected for long term history — at least the Holocene, the warm periods of which are getting less warm with each cycle. (Please correct me if I am wrong.) What a powerful combination: technology (rain guages) corrected for observation and expermentation; transparent and accountable science with vigorous “scientific” debates; a knowledge of Earth’s history and changes.

  63. Philip Finck says:

    Re: “…virtually all of the world except for China and Russia will experience increased drought by 2030 and severe drought by 2060.”

    Lets see now. Front cover of most recent Canadian Geographic; “Can You Prosper in a Hotter, Wetter World?”

    OK idiots, so which is it? Or does it really matter, it all fits Global Climate Disruption. One thing is for sure, `they’ will never be proven wrong with those types of predictions.

  64. tim says:

    “DesertYote says:
    October 24, 2010 at 8:15 pm

    The noise machine is setting up the ground work for what they anticipate might be a cooling trend. If it global temps cool, then they can start talking about drought. Warm-Wet or Cool-Dry, they will always have something to talk about, and its mans fault! ”

    You got it buddy and their carbon tax will fix all problems!!

  65. Martin Lewitt says:

    The paper demonstrates the failure of peer review in climate science. It uses the model output produced for the Fouth Assessment Report (AR4), without any acknowledgment or review of the diagnostic literature. Projections of drought without assessing the error introduced by Wentz’s finding that the models produced only one third to one half of the increase in precipitation associated with the warming are a travesty.

    This later paper by Beate G. Liepert and Michael Previdi finds Wentz’s results confirmed in latent heat fluxes.

    “Do Models and Observations Disagree on the Rainfall Response to Global Warming?”
    http://journals.ametsoc.org/doi/abs/10.1175/2008JCLI2472.1

    How did the author, his acknowledged Trenberth and the anonymous peer reviewers “miss” these papers? Maybe the only way to cleanup peer review in the climate science field is political. We need to lobby governments and legislatures to make sure that any that any model based studies they finance include a review of the diagnostic literature, and discussion of the implications of the known diagnostic issues of the models.

  66. R. Craigen says:

    A worthwhile observation but the article lacks any connection between the modelled drought and the measured rainfall. Are you saying that models are tuned to measurements that are systematically low? Also, if measurement is systematically low, and always have been, how would this affect trend inference?

    The piece is a good start, but I think it opens more questions than it closes. I guess that’s the point…

  67. Noe Me says:

    Hartmann explains that the biggest sources of error are wind-related. This is easily seen when measuring snowfall. Just before a snowflake falls into the gage, air turbulence sucks it back out tosses it overboard. Just taking a look around after a blizzard, it’s easy to imagine how difficult it is to measure snowfall. Places exposed to wind are barren, while other places are covered by meter-deep snowdrifts. How much snow really fell?

    Oh, this is a huge issue. We’ve been testing various snow gauges for a number of winters now and it’s a very time consuming task. We had to hire contractors to come and monitor the gauges and collect manual measurements for every snow fall, 24/7. Getting accurate liquid water equivalents is very difficult. A couple of years ago, we had issues with a hot plate we were deploying to the field, and the manufacturer told us that it was because we were having wind with the snow, and that wasn’t normal. We still joke about that.

  68. The Iceman Cometh says:

    My big problem with all rainfall data is that it is reported as an arithmetic average. Yet it doesn’t matter over what time scale you measure it – the distribution of rain follows anything but a normal distribution. Weibull, yes, and even log-normal is quite a good approximation, but normal it is not. That means that the arithmetic average is biased high relative to the mode (or most likely). If you rely on the arithmetic average, you will generally get less than you expect. So predictions of drought are self-fulfilling, nothing less than a simple statistical artifact.

  69. Stilgar says:

    Are there any papers discussing precipitation and land use changes?

    Would farmers changing how the farmed (irrigation methods, sprinklers vs gravity flooding, etc) as well as the types of crops grown (more water needed for some vs others).

    All would seem to influence the amount of H2O in the air.

    If there were more farms using more water in the past and fewer modern farmers using water more efficiently and drought tolerant crops could make a large difference.

  70. sky says:

    Field measurements that are systematically biased by extraneous environmental factors are nothing new in geophysics. The critical question is whether that bias is static or variable over time. In the former case, we may not know the absolute amount, but we can determine the changes reasonably reliably, and even the abolute values may be estimated well. This may be the case with rainfall. However, if the bias evolves over time in some unknown fashion, as with UHI, then the measurements provide entirely unreliable indications of the variable of interest. The two distinct cases should not be confused with one another.

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