Guest essay by Dr. Norman Page
Most climate warming alarmists have recently realized that it is now counterproductive to attribute every and all extreme weather events (even cold snowy winters) to global warming and try to project a judicious objectivity by applying the cliché “weather isn’t climate” to both sides of the climate wars. In fact weather is an almost instantaneous slice through the climate space-time phase space and certain patterns will occur more frequently on a cooling rather than a warming world.
The basic principles are very simple. On a cooler Earth the temperature gradient from the tropics to the Arctic Circle is steeper.
![FS_km5000.sm[1]](http://wattsupwiththat.files.wordpress.com/2013/06/fs_km5000-sm1.jpg?resize=600%2C315)
This increased gradient creates instability and the jet stream swings further North and South as opposed to its more West – East path during warmer periods. According to the season, blocking highs may develop with colder, drier, air penetrating further South and warm moist air reaching further North. There can be enormous temperature and humidity contrasts in the narrow boundary between these masses as warm air is sucked in from the Gulf. Conditions along such a boundary are ideal for developing the wind shear necessary for the tornado swarm development seen recently in Oklahoma.
The blocking highs also push hurricanes to the east so that hurricanes like Sandy are more likely to occur.
Note that Sandy was not a powerful Hurricane in fact it came ashore as a tropical storm. The big storm surge was the result of its long path over open water while a real cooling signal was seen in the development of blizzard conditions in the NW quadrant. This classic weather pattern is shown for today 6/02/13 in Figs 1 and 2 and occurs more often during a cooling phase of the PDO and is often triggered by an E Pacific La Nina cooling, as seen in the 6/01/13 SST anomaly map Fig 3 (h/t to The Weather Channel).
It is worth noting that the pattern seen in Fig 1 is also ideal for steering any Atlantic Hurricane which develops this season in a Sandy type direction.
Fig1
Fig2
Fig3
By contrast on a warmer world tropical SSTs are higher EL Ninos more common and more powerful category 4 and 5 hurricanes e.g. Katrina and Gilbert can develop. Their path is more E-W so that they more frequently hit the Gulf Coast or even Central America.
More generally, a cooling earth is a drier earth because the winds pick up less water vapor from the cooler oceans. In the USA the cool waters off the West Coast (Fig3) will lead to more generalized droughts in the Center, West and SW and when combined with more frequent late and early frosts and snows food crop production will be threatened. What rains do come will paradoxically come from storms leading to flash flooding further restricting food production. In California itself the south will be dryer with more forest fires while in the North more of the rains will come as snow so that increasing snow pack will ameliorate the overall dryer conditions.
Most of the ideas expressed above were included in the post “”30 Years Climate Forecast” in June 2010 on my blog at http://climatesense-norpag.blogspot.com and revisited in June 2012 in the post “30 Year Climate Forecast -2 year update.”
There has been no net warming since 1997 with CO2 up over 8%. The SSTs show a cooling trend since 2003.
The problem with the IPCC and MetOffice Climate models is that, apart from the egregious structural errors in the specific models, (assuming that CO2 is the main driver when it clearly follows temperature and adding water vapor as a feedback onto CO2 to increase the sensitivity) climate science is so complex that the modelling approach is inherently incapable of providing useful forecasts for several reasons; for starters the difficulty of specifying the initial conditions with sufficient precision. All the IPCC model projections and the impact studies and government policies which depend on them are a total waste of time and money.
The only useful approach is to perform power spectrum and wavelet analysis on the temperature and possible climate driver time series to find patterns of repeating periodicities and project them forward. When this is done it is apparent that the earth entered a cooling phase in 2003-4 which will likely last for 20 more years and perhaps for several hundred years beyond that. For the data and references supporting this conclusion check the post “Climate Forecasting Basics for Britains Seven Alarmist Scientists” and several earlier posts on Climate Forecasting and Global Cooling especially “Global Cooling – Climate and Weather Forecasting” from 11/18/13.
Here is a summary of the latest forecast based not on the particular events referred to above but on the data and references linked in the series of posts on the climatesense-norpag site.
It is not a great stretch of the imagination to propose that the 20th century warming peaked in about 2003 and that peak was a peak in both the 60 year and 1000 year cycles. On that basis the conclusions of the posts referred to above were as follows.
- Significant temperature drop at about 2016-17
- Possible unusual cold snap 2021-22.
- Built in cooling trend until at least 2024
- Temperature Hadsst3 moving average anomaly 2035 – 0.15
- Temperature Hadsst3 moving average anomaly 2100 – 0.5
- General Conclusion – by 2100 all the 20th century temperature rise will have been reversed,
- By 2650 earth could be back to the depths of the little ice age.
- The effect of increasing CO2 emissions will be minor but beneficial – they may slightly ameliorate the forecast cooling and help maintain crop yields.
- There are some signs in the Livingston and Penn Solar data that a sudden drop to the Maunder Minimum Little Ice Age temperatures could be imminent – with a much more rapid and economically disruptive cooling than that forecast above which may turn out to be a best case scenario.
How confident should one be in these predictions? The pattern method doesn’t lend itself easily to statistical measures. However statistical calculations only provide an apparent rigour for the uninitiated and in relation to the IPCC climate models are entirely misleading because they make no allowance for the structural uncertainties in the model set up. This is where scientific judgement comes in – some people are better at pattern recognition than others.
A past record of successful forecasting is a useful but not infallible measure. In this case I am reasonably sure – say 65/35 for about 20 years ahead. Beyond that, inevitably, certainty must drop.
Sediment cores in Lake George and other places in Australia indicate Australia’s SE is drier during colder periods, supporting the above. The alarmists at the Climate Commission and others say the opposite, that Australia’s SE will get drier under global warming, based on a short period of sampling and associated modelling in the late 20th century-early 21st century (the short period itself is ambiguous in this regard, showing little overall trend), yet they also say one cannot use short term periods to make long term projections. They also use sediment cores at other times, just when it suits them. Selectivity anyone?
Other government scientists then use this hotter-drier SE model to cut water from irrigators (not even being required under the Water Act to examine social impacts), build desalination plants, cancel potential dams, and so on, so it isn’t just academic fluff. If it gets colder and drier, they might be on the right track, by accident.
A more believable scenario.
Very interesting take on the question.
Thanks for the links, too. A fair bit to catch up on.
“By 2650 earth could be back to the depths of the little ice age”
Should that be 2150?
The warmer weather suits me fine, I hope you are wrong.
“Note that Sandy was not a powerful Hurricane in fact it came ashore as a tropical storm.”
Depends where it came ashore. Sandy hit Cuba as a category 3 hurricane, Jamaica as a category 2. The approach of Dr Page seems a little parochial on this matter.
More generally, a cooling earth is a drier earth because the winds pick up less water vapor from the cooler oceans.
I’d say the opposite. What drives ocean evaporation is the temperature differential between ocean surface and near surface atmosphere temperature. With solar insolation constant (in fact it will increase in a colder world), a cooler atmosphere will cause more ocean evaporation, and hence a wetter world, or at least wetter land surfaces. I’m talking perhaps a decade time span here.
It all comes back to clouds once again. We need a increase in clouds to decrease solar energy input into the tropical/subtropical oceans, in order to get a colder world. Or a decrease in clouds to get increased radiative cooling in the temperate to Arctic zones. Of course, these effects reverse at night. So, alternatively we need relative changes in day to night clouds.
So, it comes down to cloud increase/decrease in areas where there is a net energy gain/loss from solar insolation vs outgoing LWR.
In Australia, and in all likelyhood much of the rest of the world, daytime clouds have been decreasing, while early night time clouds have been increasing.
http://www.bishop-hill.net/blog/2011/11/4/australian-temperatures.html
The cause is decreased anthropogenic aerosols.
Dr. Page
Making predictions could be a risky enterprise, however calculating extrapolations from existing long term trends may be less so.
Global temperature record isn’t sufficiently long to do such extrapolation with a reasonable accuracy, but using the CET regional set of data gives far more reliable scenario:
http://www.vukcevic.talktalk.net/CET-NV.htm
Observing that there is a good correlation between global and the CET, it can be speculated that if such correlation is extended in the future than a drop in the global anomaly can be hypothesized.
Another sensible article explaining what weather does, it’s just basic meteorology, something those wedded to CAGW need to get back to, too many heads buried in the sand of the next pay check. Must say though, it is one forecast that I hope is wrong, but the signs are not good.
Regards
Keith Gordon
Evaporation is function of vapor pressure, not of temperature.
Here in Aus on SBS news tonight, one of the Oklahoma tornado broke all records. It was the widest ever at 4.5km wide.
Shouldn’t that be “… to the west …”?
The aspect that Norman misses is that the temperature gradient from equator to pole can vary BOTH from:
I) Warmer SSTs pushing the tropopause up at the equator or cooler SSTs at the equator allowing the tropopause to sink at the equator AND
ii) A warmer stratosphere above the poles relative to the temperature of the stratosphere above the equator pushing the tropopause down above the poles or a cooler stratosphere at the poles relative to the temperature of the stratosphere above the equator allowing the tropopause to rise above the poles.
The former is dependent on global cloudiness and the amount of solar energy able to enter the oceans.
The latter is dependent on the mix of particles and wavelengths from the sun varying so as to differentially affect the stratospheric temperatures above poles and equator. The solar effect is greater above the poles hence different amounts of change above poles and equator.
The precise gradient of tropopause height between equator and poles affects jet stream behaviour and climate zone positioning and thus global cloudiness and the amount of solar energy able to enter the oceans to fuel the climate system.
The changing gradient allows the weather systems to slide to and fro latitudinally beneath the tropopause which affects global cloudiness and albedo.
The global climate system is comprised of a polar / equator see-saw in tropopause height between the equator and each pole in each hemisphere.
That is the mechanical process which adjusts the throughput of solar energy as a negative system response to all forcing elements including GHGs once the basic system energy content has been set by mass, gravity and ToA insolation.
As yet, I haven’t found a real world observation that fails to fit that scenario.
Norman said:
“This increased gradient creates instability and the jet stream swings further North and South as opposed to its more West – East path during warmer periods”.
I don’t think that is what the evidence tells us. The meridional jets (more swings North and South) seem to occur when the system is cooling (correct) but it is then that the gradient seems to decline (not increase). The reason being that more meridional jets both allow faster cooling at the equator as air is moved away more effectively and more warming at the poles as air from nearer the equator is advected in more often and for longer periods.
It is well established that more zonal jets result in a larger equator / pole gradient because the stronger zonal flow isolates the polar interior which then becomes colder.
Instead, I have previously suggested this:
When the sun is active the sun reduces ozone most above the poles cooling the stratosphere and raising the polar tropopause which gives a positive AO and shrinks the polar air masses at the surface.
At the same time the more poleward zonal jets result in reduced global cloudiness and more energy enters the oceans through the wider subtropical high pressure cells.
The entire global circulation shifts poleward becoming more zonal in the process and the system warms.
That gives an increased gradient during a warming spell.
When the sun is inactive the sun allows more ozone to form above the poles warming the stratosphere and lowering the polar tropopause which gives a negative AO and expands the polar air masses at the surface.
At the same time the more equatorward meridional jets result in increased global cloudiness and less energy entering the oceans through narrower subtropical high pressure cells.
The entire global circulation shifts equatorward becoming more meridional in the process and the system cools.
That gives a decreased gradient during a cooling spell.
That way round the theory fits observations.
Extremely difficult to grant this any credibility.
If warming ‘peaked’ in 2003 why have there been two years with record breaking temps since?
The decreased temperature differential between the tropics and the poles with warming because of polar amplification of AGW has increased extreme weather because the jet stream gets destabilised with a lower temperature differential causing it to meander. Theoretically the storms that form around the jet stream will be weaker because of the warming poles, but they are carried further north and south by the meanders.
When tropical storm Sandy came ashore it may longer have been a hurricane, but the associated storm surge was around a foot higher than it would have been before AGW cause sea level rise.
‘Predicting’ the weather from frequency and power analysis of records based on derived ‘cycles’ of which the is less than three full cycles of data to define the speculative frequency is little better than looking at chicken entrails.
At least with that method you can eat the chicken afterwards.
Norman Page writes: “By contrast on a warmer world tropical SSTs are higher EL Ninos more common and more powerful category 4 and 5 hurricanes e.g. Katrina and Gilbert can develop. Their path is more E-W so that they more frequently hit the Gulf Coast or even Central America.”
This is confusing. Katrina formed and dissipated in August 2005. According to the ONI index…
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears_1971-2000_climo.shtml
…ENSO-neutral (not El Niño) conditions existed then.
Gilbert formed and dissipated in September 1988, during strong La Niña conditions.
Additionally, by including El Niños in that sentence, you’re contradicting well-established El Niño-hurricane dynamics. El Niños suppress hurricane development by creating greater wind shear in the tropical North Atlantic. Bill Gray wrote his first paper about that in the 1960s.
The one thing that the Alarmism is not providing that is important is time. While I have more faith in Dr. Page’s predictions than in anything coming from the “team”, the fact remains that as their forecasts go farther and farther afield, their rhetoric becomes more violent and threatening. Actions are but one instigation away.
Margaret Hardman says:June 5, 2013 at 1:39 am
“Note that Sandy was not a powerful Hurricane in fact it came ashore as a tropical storm.”
Depends where it came ashore. Sandy hit Cuba as a category 3 hurricane, Jamaica as a category 2. The approach of Dr Page seems a little parochial on this matter.
Total projection, due to “it came ashore” meaning on the continent, not an island.
Margaret Hardman says:
June 5, 2013 at 1:39 am
The approach of Dr Page seems a little parochial on this matter.
——————————
Uh oh, school ma’am’s here again, now lecturing us on the “fact” that Cuba and Jamaica are part of the continental United States and, if you don’t think so, you’re parochial.
That aside Margaret, is this a passive aggressive attempt to say that recent carbon dioxide increases in the atmosphere cause increased hurricane activities and strengths ?? If so, please show the data you are working with.
izen says:
June 5, 2013 at 4:05 am
When tropical storm Sandy came ashore it may longer have been a hurricane, but the associated storm surge was around a foot higher than it would have been before AGW cause sea level rise.
————————————————————-
Please show the scientific data associated with this conjecture
Izen said:
“When tropical storm Sandy came ashore it may longer have been a hurricane, but the associated storm surge was around a foot higher than it would have been before AGW cause sea level rise.”
IWhat?
t was an unusually high tide, dude. Not AGW sea level rise.
Make some more things up why don’t you?
“On a cooler Earth the temperature gradient from the tropics to the Arctic Circle is steeper.”
Why?
Réaumur:
Can’t speak for anyone else, but in my observation the entire mechanism creates a relatively stable temperature in the equatorial region. It’s there that we should look to disprove CO2-caused global warming anyway. No matter how much insolation or whatever else changes, all that ends up happening is more heat is transferred away from the tropics. The only place to go is poleward.
As I’ve said before, reduced arctic sea ice is NOT an indication that catastrophe is imminent, it’s simply an indication that the system is working right, moving heat to where it can more easily be radiated away (especially in each hemisphere’s respective winter, where energy is free to radiate continuously to outer space without any additional solar load slowing it down).
Therefore, on a cooler world, the equatorial regions will retain their relatively stable temperature, but less excess heat is moved toward the poles. There, cooling becomes increasingly effective, and some really, really cold airmasses begin to settle. Eventually they need to wobble away from the pole, and when they do they collide with that warm, moist air wandering out of the tropics.
The result is more intense weather, as the extremes collide.
@- philincalifornia and RobRoy
Who question the scientific reality of recent accelerating sea level rise.
http://www.giss.nasa.gov/research/briefs/gornitz_09/
The current phase of accelerated sea level rise appears to have begun in the mid/late 19th century to early 20th century, based on coastal sediments from a number of localities. Twentieth century global sea level, as determined from tide gauges in coastal harbors, has been increasing by 1.7-1.8 mm/yr, apparently related to the recent climatic warming trend. Most of this rise comes from warming of the world’s oceans and melting of mountain glaciers, which have receded dramatically in many places especially during the last few decades. Since 1993, an even higher sea level trend of about 2.8 mm/yr has been measured from the TOPEX/POSEIDON satellite altimeter. Analysis of longer tide-gauge records (1870-2004) also suggests a possible late 20th century acceleration in global sea level.
The global land ice mass balance continues to be very negative with accelerating loss of ice from glaciers and icecaps. If cooling was really starting since 2003 then someone needs to tell all the melting glaciers, ice caps and the summer Arctic sea ice….
From Huffington Post in re OKC tornado:
“A 2 1/2-mile wide tornado would not look like a tornado to a lot of people,” Smith said, explaining that the twister would not have a tapered funnel and would instead resemble a dark cloud hanging below the horizon.
Er, how does one see a cloud hanging *below* the horizon?
@- Eustace Craunch
“Er, how does one see a cloud hanging *below* the horizon?”
Same way you see a ship appearing from below the horizon. The upper parts are visible before the lower parts which are revealed only as it gets nearer?
Patrick says:
June 5, 2013 at 2:29 am
Here in Aus on SBS news tonight, one of the Oklahoma tornado broke all records. It was the widest ever at 4.5km wide.
Widest *ever*? How do we know the width of a tornado in 1936, 1925, 1896…?
In the year 2525,
If man is still alive…..
“Eustace Cranch says:
June 5, 2013 at 6:03 am”
That’s my point. How do they know that this years event was the “widest evah”, “A record broken”?! (Should be a broken record) The truth is, “they” don’t. They have no idea. BUT alarmism sells well in Aus. It’s rather funny in fact. It’s like one of those “Say what?!” moments.
@philincalifornia says
“Uh oh, school ma’am’s here again, now lecturing us on the “fact” that Cuba and Jamaica are part of the continental United States and, if you don’t think so, you’re parochial.
That aside Margaret, is this a passive aggressive attempt to say that recent carbon dioxide increases in the atmosphere cause increased hurricane activities and strengths ?? If so, please show the data you are working with.”
The first sentence is rather a twisted way of saying what I already know but what the esteemed Dr didn’t spell out. I am certain that Cubans and Jamaicans don’t view coming ashore with the same slackness of meaning.
That aside, I am not the one trying to prove anything here. Dr Page is. There is no necessity for me to do so. He has put up something that is presumably falsifiable. No one has to put up an alternative theory or explanation. I was merely pointing out a sloppy piece of writing, as I am sure others will do in my own language from now on.
Réaumur says:
June 5, 2013 at 5:21 am
“On a cooler Earth the temperature gradient from the tropics to the Arctic Circle is steeper.”
Why?
Reversal of the fact that the poles have warmed more than the tropics with warming.
“The only useful approach is to perform power spectrum and wavelet analysis on the temperature and possible climate driver time series to find patterns of repeating periodicities and project them forward. “
Not really, because you do not know from that analysis the time phases of the periodicity and you do not know the cause of the geometry.
A better approach is taking the real astronomical geometry of all the solar tides:
See Solar tides vs hadcrut3
V.
Patrick,
I did think you were being a bit sarcastic. Glad you confirmed it.
Since CO2 acts like a blanket it spreads the heat more evenly and makes storms less violent.
Jut remember basic thermodynamics. The alarmists hate this simple fact.
The strongest winds in the solar system are on Neptune where temperatures are almost absolute ZERO !
It sounds like what I learned in physics. Its the difference in potential across a boundary that generates energy. Bigger temperature difference=more energy for storms.
“On a cooler Earth the temperature gradient from the tropics to the Arctic Circle is steeper.”
I disagree since the North pole has warmed more than the rest of the planet.
The South pole has cooled slightly !
Eustace Cranch, you are welcome. I admit, I should use the sarc on/off tags, British humour is usually subtle and mine is rather dry (Maybe that’s the Irish, Belgian, Australian, New Zealand and Ethiopian influence? *shrugs*). However, in Aus, we have two, state funded (I love my tax $$’s being “spent wisely”), predominantly and seriously pro-AGW news outlets. One is ABC the other is SBS. Any bad “weather event” is shown. Tornados in the US, floods in Germany etc etc. Although rarely stated, the subtext is AGW driven climate change the cause. It’s there, like the itch you can’t get to (Unless there is a tree nearby. Bear/tree/itch, you get the picture).
It is an election year after all in Aus, and the “Queen” of the most expensive “proice ohn carbohn”, Gillard, will find out how (I hope) most Aussies appreciate that on 14th Sept. If Ford is any example, as well as the 2010 election result, maybe “Aussies” will “wake up”. I won’t hold my breath!
izen says:
June 5, 2013 at 5:57 am
Most of this rise comes from warming of the world’s oceans and melting of mountain glaciers, which have receded dramatically in many places especially during the last few decades.
=========
I spent 20 years offshore, sailing the Pacific and Indian Oceans in small boats. The charts for all the remote islands were drawn 200-300 years ago, during the Age of Exploration. These charts are exceedingly accurate, to 1 foot resolution, drawn by the likes Cook, Bligh, Vancouver and Flinders. They were painstaking in their efforts because their very lives depended on getting it right.
And what do these charts tell us? There has been no significant sea level rise over the past 200-300 years. The rocks awash at low tide are still awash, even after centuries have passed. This would indicate that any changes we are seeing a either local or cyclical in nature, or so slow that the natural accumulation of soils and reefs along with the industry of humans keeps pace.
Worst case, one satellite is showing about 1 foot per century in rise, over a very short period. About what the IPCC itself projects for the next century. And this is reason to worry, to shut down the world’s economy, to deny Africa access to coal to industrialize as we did in the west? Is the world going to once again impose slavery on Africa, slavery to artificially high energy costs? Have we learned so little since 1807?
If the past is a predictor of the future (but wait! We need a mechanism), the rest of this century will see deep intrusions of cold air over the northern hemisphere continents in wintertime. Tropical activity should continue to decrease until 2040, based on a 60 year cycle with the last minimum in 1980 and, based on a 1200 year cycle, after the year 2150 a warm period analogous to the Medieval Warm Period will arrive and last 350 years. The balance of this century could be rough. We should get ready. We have been flummoxed by the warmists into ignoring the past.
“ferd berple says:
June 5, 2013 at 6:41 am”
You are correct. In the hundreds of years of Royal Naval history, and sea “data”, there is no evidence of any significant sea level rise.
Volker Doormann says:
June 5, 2013 at 6:18 am
A better approach is taking the real astronomical geometry of all the solar tides:
=============
correct. it is how we calculate the ocean tides on earth. we don’t do it from first principles the way they try and simulate climate with models, because it doesn’t work. The process is inherently chaotic and you cannot cancel chaos by treating it like a random process. It only appears random due to limited sampling.
Every physical object has natural frequency(s), which will resonate in response to cyclical forcings. This resonance will far exceed the response expected from non-cyclical forcings. Thus, over time cyclical behavior will dominate the system and can be used to make predictions.
For example: The ocean tides on earth would be about 1 foot in height due to the combined gravitational pull of the moon and sun. Yet we routinely see tides much higher than this. It is rare to find any location with a maximum tidal range of only 1 foot. The reason we see higher tides is because the relative motion of the earth, sun and the moon creates an oscillation. In effect the water in the oceans starts swirling around like water in a rocking bowl of water, in phase with the motion, which amplifies the tidal range.
So, we calculate tides very much the way we calculate horoscopes, by using the position of the sun, moon and planets in the sky in relation to historical observation. Who’d have thought. Astrology delivering a more accurate prediction than science.
izen says:
June 5, 2013 at 5:57 am
———————————
To the extent that on some coasts sea level has risen slightly since the end of the Little Ice Age c. 1850, the fantasy of AGW has nothing to do with it. Sea level in NYC is about a foot higher now than during the big 1821 storm, but natural warming of the ocean & sinking land explain that insignificant change with room to spare, without human culpability. Seal level rise is not accelerating, but decelerating.
The ability to do work is not dependent on temperature but on temperature gradient. In fact the hoary old saying “nature hate a vacuum” could be better stated as “nature hates a gradient”.
Patrick says:
June 5, 2013 at 6:53 am
You are correct. In the hundreds of years of Royal Naval history, and sea “data”, there is no evidence of any significant sea level rise.
===========
Which explains why “the Team” uses proxies like sea sediment to judge sea level rise, rather than simply looking at the single most authoritative reference on sea levels in the world. The British Admiralty charts.
Every navy in the world, hundreds of millions of miles in cargo shipping, they all use charts based on the BA charts drawn 200-300 years ago. Most of the worlds oceans has never been resurveyed since then. (there are places still unsurveyed, such as Bligh water in Fiji and parts of the coast of Sarawak in Northern Borneo – from first-hand knowledge). And while we do see datum corrections on the charts for GPS, WGS84, etc. nowhere is there a datum correction for global sea level rise.
Think about it. There is a claim of significant sea level rise. Yet the naval charts, the charts on which so much of the world depends for commerce and safety, these charts have no mention of global sea level rise. Well, if it happening, why isn’t it on the charts? There is a rule in business. If it isn’t written down, it didn’t happen.
“ferd berple says:
June 5, 2013 at 7:15 am
Think about it. There is a claim of significant sea level rise. Yet the naval charts, the charts on which so much of the world depends for commerce and safety, these charts have no mention of global sea level rise. Well, if it happening, why isn’t it on the charts? There is a rule in business. If it isn’t written down, it didn’t happen.”
Exactly! It’s rather a hoot isn’t it and one “alarmists” just don’t get! however, AFAIK, one has to pay to see the RN archives these days. Take Henry the 8th’s Mary Rose…was sunk off Portsmouth…and not “discovered” for ~450 years. No significant SLR in ~450 (Assuming land levels were the same).
Vukcevic@2.13 (Volker Doorman@6.18)
You say
“Making predictions could be a risky enterprise, however calculating extrapolations from existing long term trends may be less so.”
I assume you mean the risk of being wrong. Because I’m retired I don’t have to worry about academic peer pressure,getting published or institutional funding so I can call it as I see it.
Extrapolation from existing trends is really my approach. I agree with the early decadal extrapolations on the graph you linked to. Eyeballing it, it looks like the peaks are suspiciously close to the 60 year PDO cycle which incidently is 3 times the Jupiter Saturn lap period for those like Volker who wish to speculate about mechanisms.(Thats a clue for Leif Svalgaard)
All I do is to make the perfectly reasonable assumption that the recent temperature peak was a peak in both the 60 year and a millenial solar cycle.and that the trends for 2000+/- to 3000+/-
will repeat the 1000- 2000 trends with a little extra cooling because of the longer term decline to the next Big Ice Age. Having some passing acquaintance with the proxy literature I would suggest that the currently most useful compilation for thinking about the record of the last 2000 years is.Fig 5 in Christiansen and Ljungqvist 2012
http://www.clim-past.net/8/765/2012/cp-8-765-2012.pdf .
This is Fig 3 in my post at http://climatesense-norpag.blogspot.com/2013/05/climate-forecasting-basics-for-britains.html
Those areas on the charts marked “unsurveyed” stick with me years later. Each time you sail through one of them you develop a healthy new respect for the men and ships that went before, when the whole world was marked “unsurveyed”.
Normally the charts show fathoms and feet, nice friendly reassuring numbers that you have enough water under the boat. That there isn’t some hidden danger up ahead, waiting to tear the bottom out of your boat. Then in some remote region, where you are well and truly on your own, the numbers stop and “unsurveyed” appears, signalling the edge of the known world. And there is no way around, except to go forward.
Dr. Page ended his article, saying:
“In this case I am reasonably sure – say 65/35 for about 20 years ahead. Beyond that, inevitably, certainty must drop.”
Margaret Hardman alleges @ June 5, 2013:
“That aside, I am not the one trying to prove anything here. Dr Page is.”
——
Dr. Page’s comment hardly represents an attestation of “proof”. At best, he simply asserts his way of looking at things.
From memory the “British” (Don’t quote me on this) discovered a “trench/hole” in the Pacific and was found later to be 6 miles deep?
Margaret Hardman says:
June 5, 2013 at 1:39 am
Gawd, Margaret, what do you have for lunch, testosterone sandwiches with a side of frightened schoolchildren?
You said: Sandy hit Cuba as a category 3 hurricane, Jamaica as a category 2.
I say:
… it made landfall near Bull Bay, Jamaica as a moderate Category 1 hurricane …
http://en.wikipedia.org/wiki/2012_Atlantic_hurricane_season#Hurricane_Sandy
(please bear in mind the above reference has been approved by the guardian of all things global warming on wiki – William the Weasel)
@Patrick says:
June 5, 2013 at 7:48 am
http://en.wikipedia.org/wiki/Challenger_Deep#History_of_depth_mapping_from_the_surface
Steven Devijver says:
June 5, 2013 at 2:22 am
” ” More generally, a cooling earth is a drier earth because the winds pick up less water vapor from the cooler oceans.”
Evaporation is function of vapor pressure, not of temperature”
Steve, I can’t leave you with this misunderstanding (I thought someone here would have pointed it out before now – function of vapour pressure, correct but vp itself is a function of temp.
.http://courses.chem.psu.edu/chem12h/vapor.pdf
Indeed, at 10C the saturation vp is double that at 0C and at 20C is double that at 10C, not quite redoubles at 30 C.
“John Tillman says:
June 5, 2013 at 7:56 am”
Thanks for that.
“More generally, a cooling earth is a drier earth because the winds pick up less water vapor from the cooler oceans.”
I would think that the polar/NH to equatorial temperature gradients driving average higher wind speeds would result in MORE water evaporation (think unheated hand dryers in rest rooms everywhere). And based on my experience with swimming pools, temperature would be a minor factor relative to wind speed. The higher evaporation would cause water/air cooling and possibly drive higher cloud cover with increasing amounts relative to NH distance to the equator, reducing effective solar input even more (on average). Then once the snow cover kicks in…… A possible downward spiral making warm periods the exception?
Without getting into a lot of detail about the mechanisms, which are conjecture at this point, (we don’t really know), when we are in a cool phase the Arctic is cooler, sea ice increases, and systems moving to the south from the high latitudes are colder. However, over a whole cycle, the tropics both warm and cool much less than high latitudes, with very little change at the equator. Thus air masses moving up from the south do not cool as much as those moving down from the Arctic. Hence, when such masses meet, in a cooler world there is a larger temperature gradient at the interface, which will fuel more powerful storms, at least for tornadoes over North America. Murray.
To author Norman:
All your conclusions are good and correct, the driving forces behind
the cooling process are 5 macro-forcings, calculated in
http://www.knowledgeminer.eu/eoo_paper.html
Take a look, cheers JS
murrayv says:
June 5, 2013 at 8:08 am
“…in a cooler world there is a larger temperature gradient at the interface, which will fuel more powerful storms, at least for tornadoes over North America.”
Hmm… based on what? Looking at tornado statistics over the last 100 years, I can’t discern any correspondence of incidence to global average temperature, either warming *or* cooling.
I think Dr. Page is probably wrong about the 1000 year cycle. It bottomed near the middle of the 6th century, peaked in the 11th century, bottomed again in the late 17th century (about 1100 years ?), so the next peak should be expected about the middle of the 23rd century. Whenever I see comments about the various solar cycles, the Jose cycle (180 years) seems to be ignored. Looking back at the last few centuries a case can be made for a Jose peak about 1940-45., which would suggest the next bottom about 2030-35. The 60 year cycle probably did peak about 2003/5, so will also bottom near 2035. We also have a solar deep grand minimum under way, for which the coldest period might be near 2035. I think Vukcevic’s projection is right for the coming bottom, but fails to take into account the ca 1100 year cycle and the Jose cycle for his projection from there on. The LIA had all of these cycles bottoming. Tis time we lack the 1000 year cycle bottom. The descent into the next really cool period should bottom in the 28th century – like the LIA or the end of the current interglacial? Murray
This scenario is actually more troubling than 3 deg C warming.
Murayv I said
” I would suggest that the currently most useful compilation for thinking about the record of the last 2000 years is.Fig 5 in Christiansen and Ljungqvist 2012
http://www.clim-past.net/8/765/2012/cp-8-765-2012.pdf .
This is Fig 3 in my post at http://climatesense-norpag.blogspot.com/2013/05/climate-forecasting-basics-for-britains.html”
The closest millenial cycle is probably the most relevant – the 1000 peak seems pretty good here.
See also Fig 2 in the last link for the miennial cycle.periodicity.
James@48 Very true. I’m hoping people will realise that themselves. I don’t want to sound like a reverse alarmist by stressing the point.
Philip Bradley
http://www.climatedata.info/Impacts/Impacts/dust_files/BIGdust_-_epica.gif.gif
The changes am seeing to the jet stream over here in the UK all point to a cooling climate.
l have noticed the pattern changing since 2007, where they has been a increasing trend in the jet stream moving south. lt started off been mostly during the summer months, but now its extending to the rest of the year. The current jet stream pattern over europe does not bode well for the coming winter. Because if the current pattern stays in place then its risk on for a other winter like 1962/63 to take place here in europe.
“Winter is coming.”
OT: http://ezralevant.com/2013/06/taking-on-turbine-towers.html
lgl @ 9.38. Your link illustrates my colder – dryer point beautifully. Thanks.
Speaking of Sandy by an odd coincidence I captured the birth of Sandy…..http://markesanchez-marke.newsvine.com/_news/2012/10/28/14762575-the-spirit-of-the-atlantic-surveys-his-realm
John Tillman says:
June 5, 2013 at 7:08 am
izen says:
June 5, 2013 at 5:57 am
———————————
OK Izen, John beat me to it, but thanks for your answer.
You provided data relating to sea level rise (albeit questioned by other commenters), BUT provided zero data supporting the rest of the assertions in your post. So we can let WUWT readers assume that there isn’t any. That would fit with my observations too, as I can’t find any either.
From http://www.nasa.gov/mission_pages/hurricanes/archives/2012/h2012_Sandy.html
“Sandy Was Still a Hurricane After Landfall
On Oct. 29, 2012 at 11 p.m. EDT, the center of Hurricane Sandy was just 10 miles (15 km) southwest of Philadelphia, Penn., near 39.8 North and 75.4 West. Sandy was still a hurricane with maximum sustained winds near 75 mph (120 kph) and moving northwest at 18 mph (30 kph). Sandy’s minimum central pressure had risen to 952 millibars. The hurricane-force-winds extended 90 miles (150 km) east of the center of circulation. Tropical-storm-force winds, however, went much further, as far as 485 miles (780 km). ”
This is interesting as well http://www.nhc.noaa.gov/data/tcr/AL182012_Sandy.pdf
By the way, Billy, are you any relation of Keith Waterhouse?
Admission of error: Sandy reached Jamaica as a cat 1 hurricane.
Dr Norman Page says:
June 5, 2013 at 7:25 am
“All I do is to make the perfectly reasonable assumption that the recent temperature peak was a peak in both the 60 year and a millenial solar cycle.and that the trends for 2000+/- to 3000+/- will repeat the 1000- 2000 trends with a little extra cooling because of the longer term decline to the next Big Ice Age. “
Well, see. There are some traps. An analysed 60 year cycle is concluded from a temperature spectrum with a calibrated time scale from what? Timescales from isotopic samples do not have the astronomical accuracy. It can be shown that some relevant FFT power peaks are fitting with the solar tides only, if the time scale is shifted by a factor. This suggests that the isotopic calibration is not correct, and if this is true, then it is possible that the value of the 60 years is also not correct.
An other trap is the power strength of a temperature peak. In general the frequency dependence is a well known 1/f² function, and the frequency is the synodic tide frequency. But if the function of a cycle is not a simple sinusoid function, there do appear higher harmonics at higher frequencies. This is the case for a near ‘200’ year cycle in the spectrum, but it is still the 5th harmonic of the main solar tide period of ~900 years. To calculate the temperature approach it is therefore unalterable to calculate the strength of each single tide frequency out from the 1/f² law and take the real astronomical tide function, which has never a sinusoid shape. Only by this doing one gets a good temperature approach and a good temperature forecast.
Regarding the mechanism of solar physics, it is remarkable that the Neutrino capture rate correlates positive with the hadcrut4 temperature.
There is – known since G. Bond – a ~900 year climate period, from which the Little Ice Age is a triple minimum, and it will repeat again in some centuries; This is not to be mixed up with the saw tooth like Big Ice Age periods of 41 ky or 90 ky. At present the sea level rise has finished in praxis and has started some 15.000 – 20.000 years ago. With the long cooling phase of maybe 40 ky to 90 ky the next Big Ice Age will not repeat prior to that time span.
izen says:
June 5, 2013 at 5:57 am
“The global land ice mass balance continues to be very negative with accelerating loss of ice from glaciers and icecaps. If cooling was really starting since 2003 then someone needs to tell all the melting glaciers, ice caps and the summer Arctic sea ice….”
Melting depends not on the differential of temperatures but on temperatures. Why do you warmists never argue rationally?
Dr Norman Page says:
June 5, 2013 at 7:25 am
Extrapolation from existing trends is really my approach. I agree with the early decadal extrapolations on the graph you linked to. Eyeballing it, it looks like the peaks are suspiciously close to the 60 year PDO cycle
That may be the case, but I am not entirely convinced since periods vary between ~45 and ~65 years (top graph)
http://www.vukcevic.talktalk.net/NVb.htm
indeed average since 1650s is 60 years, but the PDO’s records are not long enough to make a conclusive judgment.
On the other hand the CET periodicity follows closely the tectonic events in the N. Atlantic which are unlikely to be caused by PDO, but they are loosely correlated to solar activity (last graph), something in future science may wish to consider.
The actual temperature curve is the end result of interactions between the phases of multiple drivers .First the Milankovic orbital cycles and then solar cycle activity cycles of various lengths.I believe that the neutron count is a good proxy for solar activity mainly the solar magnetic field strength.and captures most of the first principal component.Using wavelet analysis you can see the amplitude of any resonances come and go through time. At certain periods some frequencies are more prominent than others.Forecasts can be based on repeat periodicities operative closest in time to the start point where other things are most likely to be eaqual In this case I really believe the
Christiansen et al time proxy series linked at my 9.02 post is most useful. It checks well against the written climate and weather record reported eg in Fagans book “The Little Ice Age”
The uncertainty lies in whether we are at the peak of a millenial cycle or not – right now it sure seems reasonably plausible looking at the Christiansen reconstruction.
izen says:
June 5, 2013 at 5:57 am
@- philincalifornia and RobRoy
Who question the scientific reality of recent accelerating sea level rise….
>>>>>>>>>>>>>>>>>>>>>
…have paid attention to their geology courses sea level rise graph.
(The hysteria about ‘Sea Level Rise’ would be hysterically funny if it wasn’t used as a political club.)
izen says: @ June 5, 2013 at 5:57 am
The global land ice mass balance continues to be very negative with accelerating loss of ice from glaciers and icecaps. If cooling was really starting since 2003 then someone needs to tell all the melting glaciers, ice caps and the summer Arctic sea ice….
>>>>>>>>>>>>>>>>>>>
Some One DID.
Again you are not paying attention to the longer view.
H/T to John Kehr, the Inconvenient Skeptic. (Leave it to an engineer to have both feet planted firmly in reality.)
Dr Norman Page says:
June 5, 2013 at 12:15 pm
“The uncertainty lies in whether we are at the peak of a millenial cycle or not – right now it sure seems reasonably plausible looking at the Christiansen reconstruction.”
The caveat would be resolution of the proxies, for the same reason that it is incorrect to append a high resolution recent instrumental series to a low resolution one. The older data may have variability greatly reduced compared to recent data. One must be sure he isn’t looking at a hockey stick.
Of all the online ‘discussions’ I’ve had, the most “blank stare” and non sequitor responses I’ve ever received were on this very topic when attempting the explain cold/dry versus warm/moist air masses driving weather events in conjunction with the concept that global warming happens more at the poles than the tropics. A warmer earth should, in general, bring fewer not more extreme weather events.
Eustace Cranch says:
June 5, 2013 at 6:03 am
Patrick says:
June 5, 2013 at 2:29 am
Here in Aus on SBS news tonight, one of the Oklahoma tornado broke all records. It was the widest ever at 4.5km wide.
Widest *ever*? How do we know the width of a tornado in 1936, 1925, 1896…?
>>>>>>>>>>>>>>>>>>>>>>>.
widest ever at 4.5km wide??? (4 miles is = 6.44 kilometers)
The tornado was so strong it drove straw through telephone poles. You could still see the path where it leveled everything a half decade later.
murrayv says:
June 5, 2013 at 8:28 am
I think Vukcevic’s projection is right for the coming bottom, but fails to take into account the ca 1100 year cycle and the Jose cycle for his projection from there on.
Thanks for the expression of confidence, but time will tell. In the CET extrapolation I used only periods below 100 years, since I think it is necessary to have at least three full periods for a particular frequency to be considered at least semi-permanent feature. Thus, both Jose and 1100 cycles even if they exist can’t be validated from the CET data with the required degree of confidence.
Pochas – Take a look at the Christiansen et Al methods. They say
“The proxies are of different types and of different resolutions (annual, annual-to-decadal,
and decadal) but all have previously been shown to relate to local or regional temperature. We use a reconstruction method, LOCal (LOC), that recently has been shown to confidently
reproduce low-frequency variability. Confidence intervals are obtained by an ensemble pseudo-proxy method that both estimates the variance and the bias of the reconstructions.
The two-millennia long reconstruction shows a well defined Medieval Warm Period, with a peak warming ca. 950–1050AD reaching 0.6 C relative to the reference period 1880–1960.” AD.
This is why I place some confidence in their reconstructions.
Good thread, with input from various posters we can piece together some plausible dynamics with solar influences which also include terrestrial cycles. There is no doubt that this topic is complicated. The simplistic, opportunistic method of matching model predictions to past weather is demonstrably faulty. The increase in positive AO in the 80’s and 90’s, for example, was “predicted” by models in the early 2000’s. The current negative AO excursions are now also “predicted” by models along with handwaving about sea ice.
As near as I can tell, the models flipped from +AO to -AO with a 2005 paper with some rather speculative modeling. The rhetoric got ramped up with the 2009/10 negative AO causing east coast (DC and surroundings) snowstorms. The obvious motivation was the need to explain increased snowfall to gullible politicians. The sea ice anomalies explanation was especially implausible considering the sea ice boundary is always somewhere and shifting it is not going to alter the dynamics of the flow.
One point of disagreement with the OP, I don’t think meridional flow is some sort of feedback from warming or cooling, dictated by the temperature gradient. The causes of perturbations in the flow are much too complex to be considered feedback. All weather is local and the average gradient, like the average global temperature and average humidity does not matter in the least to any of the weather. The gradient from the perturbations overwhelms the averages.
I too have looked at history to ‘forecast’ the future – see http://meteosoft.wordpress.com/
I’ve identified the following long term ‘cycles’ (ignoring the more chaotic short term oscillations):
6000 Yr – peak circa 1200BC and a trough circa 1800AD
1100 Yr – the Minoan (1100BC), Roman (1AD) and Medieval (1600-1800AD) warm periods
64 Yr – PDO/AMO
21 Yr – Hale Cycle
Add a small temperature increase for CO2 (0.0052 degC / Yr) and you get (as an Excel function):
Public Function GlobalTempAnomBase8110(Year As Integer) As DoublePi = 3.1415926
GlobalTempAnomBase8110 = (0.5 * Cos(Pi * (Year + 1000) / (6000 / 2)) + 0.31) +
(0.5 * Cos(Pi * Year / (1100 / 2)) - 0.3) +
(0.15 * Sin(Pi * (Year - 4) / (64 / 2)) - 0.04) +
(0.04 * Sin(Pi * (Year - 4) / (21 / 2)))
If Year > 1944 And Year < 2136 Then
GlobalTempAnomBase8110 = GlobalTempAnomBase8110 + 0.0052 * (Year - 1944)
Else If Year >= 2136 Then
GlobalTempAnomBase8110 = GlobalTempAnomBase8110 + 1
End If
End Function
This formula, when plotted against the 10 year moving average of the global temperatures (excluding GISS which I don’t trust!), I get a correlation coefficient of 0.989, which is an excellent fit.
This additional temperature increase was anchored to 1°C in 2136, as it is assumed that more efficient, cheaper, non-fossil fuel energy sources would be widely used by then.
Rob
Meteosoft – You havent looked at History too closely if you think the MWP was 1600 – 1800.
Dr Norman Page says:
June 5, 2013 at 6:53pm
“You havent looked at History too closely if you think the MWP was 1600 – 1800”
Oops, and thanks…
Meant:
1600-1800AD of course was the LIA
Rob
Dr. Norman Page claims that Sandy came ashore as a tropical storm.
Not true – Sandy came ashore as an extratropical storm, a Nor’Easter.
Also, Sandy’s strongest sustained winds as determined by the
National Hurricane Center (often extrapolated from winds at levels
other than the standard 10 meters above surface) were slightly
above hurricane force. And unusually, on the left side of the storm,
south of the center, over water and in an offshore direction.
There was 1 measurement of 75 MPH sustained wind (1 minute
average), at 18 meters above an island surface. There was 1
other measurement at a lower elevation that translates by usual
rules to 78 MPH. So, there is fair chance that spotty 74-plus MPH
sustained winds occurred at 10 meters above land.
It could be correct that Sandy was no longer capable of achieving
hurricane-qualifying winds 10 meters above land when Sandy made
landfall. But the National Hurricane Center made a determination
that this was occurring over water in an unusual part of the storm.
That may be related to the storm having gone through a transition
to an especially strong extratropical type storm.
I forgot to mention a couple sources:
http://www.nhc.noaa.gov/data/tcr/AL182012_Sandy.pdf
(especially towards the bottom of page 5)
http://www.nhc.noaa.gov/archive/2012/SANDY.shtml?
especially:
http://www.nhc.noaa.gov/archive/2012/al18/al182012.public.030.shtml?
http://www.nhc.noaa.gov/archive/2012/al18/al182012.update.10292255.shtml?
http://www.nhc.noaa.gov/archive/2012/al18/al182012.update.10300002.shtml?
http://www.nhc.noaa.gov/archive/2012/al18/al182012.public.031.shtml?
Notable: http://www.nhc.noaa.gov/archive/2012/al18/al182012.fstadv.030.shtml?
This says hurricane force sustained winds were confined to south of
the center at 7 PM, an hour before landfall.
Forecast for a few hours after landfall (2 AM) was max sustained
winds 1 knot above “hurricane qualifying”, and confined to the southeast
quadrant of the storm.
The intervals between the Roman , MWP, and the current warming look closer to a 900 year cycle than they do a 1k cycle. The trick is how far along are we on any given cycle.
ferd berple says: June 5, 2013 at 6:58 am
Volker Doormann says:
June 5, 2013 at 6:18 am
A better approach is taking the real astronomical geometry of all the solar tides:
=============
So, we calculate tides very much the way we calculate horoscopes, by using the position of the sun, moon and planets in the sky in relation to historical observation. Who’d have thought. Astrology delivering a more accurate prediction than science.
I do know very well, that Anthony would not have any astrology discussion his blog, and do respect that.
For clearness of the subject I would like say some words.
To predict the long term *) global climate tides from the solar tides as an effect from neighbour couples, it needs not only the heliocentric ecliptically positions of the objects, it needs also the strength of the solar tide effect. This is very easy, because one can show that the strength function follows a simple 1/f² law; the ~900 year period of Little Ice Ages shows a bigger effect in the global temperature (~ +-2.0 K) than effects from the inner Jupiter couples (~ +-0.1 K).
*) To predict the short term global climate, the solar tides have to modulated with the strong oscillations of the ocean streams resulted from the resonating earth axis frequency (Chandler) and its sub harmonics with the Jupiter frequency of 0.08432 y-1 (10:1, 5:1, 5:2, 10:3).
The geometry of the solar tides controlling the terrestrial global climate is based on astronomy and its laws given by Johannes Kepler and Simon Newcomb. The strong coherence of the geometry with the global temperature, plus the 1/f² law for the strength, suggest that there must be a physical mechanism between, and this holds as scientific argument also, if the kind of mechanism is unknown till now.
These points are scientific arguments using the astronomical solar synodic tide functions as base. Beside other trigonometry gymnastics of mathematic terms detached from any real geometric structures, this, my behaviour is unique, because it is the only method with a real geometric astronomy structure as base. No fantasy cycles named after authorities in discovering cycles of years with variations of 50% or greater.
Thank You.
V.
“Gail Combs says:
June 5, 2013 at 1:43 pm”
It’s not unusual for the pro-AGW MSM in Aus to not get their history and facts correct. It’s an election year, SBS is an alternative Govn’t propaganda outlet to the usual ABC. An election year and far to many Aussies are falling for the alarmist “carbon driven climate change” tripe broadcast each and every day.
If my memory serves, I have seen images of that event. One that sticks in my mind was a picture of a 4X2 section of wood had punctured both walls of a front tyre and then in on through the firewall into the engine bay, all driven by the storm.
Dr Norman Page says:
June 5, 2013 at 12:15 pm
“The uncertainty lies in whether we are at the peak of a millenial cycle or not – right now it sure seems reasonably plausible looking at the Christiansen reconstruction.”
I’m not sure about extracting anything conclusive from proxy reconstructions. Loehle 2007 and 2008 has proxy peaks and valleys all over the place, largey missing the dark ages minimum and putting the MWP peak as early as 880. Historic records suggest a real dark ages (migration?) minimum in the 6 century and also suggest that the MWP optimum was probably later, more likely late 11th century.
Also see : http://scienceandpublicpolicy.org/images/stories/papers/reprint/holocene.pdf
http://scienceandpublicpolicy.org/reprint/holocene_temperature_records_show_millennial_scale_peroidicity.html
The analyses of several different proxy records of past temperatures provide a large set of apparent cycles that seem to group into a near 1000 year cycle and a near 1500 year cycle.
All values presented (extracted by the method of analysis from the data presented) for the near 1000 year cycle are 1000 (faint), 1030, 1067, 1089, 1152, 1190, 1200 and 1230 years. The authors find a 1013 year mean without saying exactly how. The average of the values given above is 1120 years. Excluding the questionable 1000 year case, the median value is 1089 years. Using the extremes a value could be inferred of 1130 +- 100 years. Perhaps 1100 years would be the best estimate to use.
For the near 1500 year cycle we find mentions of a possible 1339 year case and more likely 1408, 1436, 1470, 1479, 1486, 1527, 1552, 1571, 1650, 1660, 1667, and 1681 year examples. The authors find a 1525 year mean. Using all of the above I find a 1533 year mean, or excluding the doubtful 1339 years, a mean of 1549 years. Using all of the values, the median is 1527 years and the range would be 1510+-170 years. Excluding the 1339 case the range would be 1540+-140 years. If we leave out the 4 values greater than 1600 which seem rather anomalous we are left with a mean of 1491.
Given the margin of error on any of the estimates, the simple original value of 1500 years seems good enough.
We seem to have 2 possible cycles, 1100 years and 1500 years.
The authors also find 2 groupings for the date of the MWP peak. The first is AD 798, 833, or 948, giving a mean about AD 860. The second group is AD 1036, 1047, 1088 and 1138 giving a mean of 1077. The latter value seems more consistent with most other findings. The range for this group would be 1087+-51 years. Probably AD 1100 is a good value to use. Was there an earlier peak near AD 860?? . Loehle 2007 finds the main peak about 880-900 and the second lower peak about 1000.
Using AD 1100 for the MWP and adding 1100/2 = 550 years would put the bottom of the LIA at AD 1650. Other estimates seem to place it closer to 1670-1680. The next long cycle warm peak would be about 2200, but not likely before 2150 (1650+500).
Murray
Norman
I agree with you that a cooler climate may mean more storms than warmer climate .Nowhere is this more apparent than when it comes to tornadoes in the US, In the case of Strong to Violent Tornadoes F3+ , there was a strong cluster of these between 1954 and 1974. Of the 21 years in this period, 16 out of 21 had colder than normal spring and the years with the most strong tornadoes had colder than normal spring [with the exception of 1974]. This year is following the same pattern with April and March below normal temperatures and the tornado count is up. I have not seen the figures for May yet , but again strong tornadoes happened in this month. With colder years being projected for the next several decades, there is a greater probability of many more cooler springs and more stronger tornadoes as well like the 1950-1970’s
Meteosoft says: June 5, 2013 at 6:22 pm
I too have looked at history to ‘forecast’ the future – see http://meteosoft.wordpress.com/
Meteosoft, your calculation is very interesting. I agree that we are notb yet at theb warm peak of this long cycle, and that the next bottom is about whare you show it. However, I doubt theb 6000 year cycle. I think you are seeing a long cooling trend since the holocene optimum. A similsr trend shows up in the Eemian. Also you might consider the Jose cycle of very near 180 years. There is probably also a Deep Grand Minimum solar cycle of about 360 years – See “Climate and Solar Regularities” at http://www.agwnot.blogspot.com.. Murray
Tornadoes are rare on the Canadian Prairies but they do occur occasionally and they have happened when temperatures are unseasonably cool. The Regina Cyclone of 1912 with 28 deaths, the Kamsack tornado in 1944 with 2 deaths and even the extensive tornadoes experienced in 2010 share one thing in common. They were preceded by cooler daytime temperatures than those that are more commonly experienced for that time of year. Perhaps it is anecdotal but I would entirely agree with the premise that a cooler than average year is more likely to produce a tornado as opposed to a hotter drier year, especially in the Canadian Prairie region of North America.