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Post by poitsplace on Apr 3, 2009 20:43:19 GMT
Because some effects which have a significant effect over short time periods don't have a significant effect over long time periods (and vice versa). For example ENSO affects the temperature a lot over a single year. A strong el nino will make a very warm year, or a strong la nina year will make a very cool year. But over say 30 years the el ninos and la ninas largely come in equal number and cancel out therefore dampening their effect on a multi-decadal time scale. Yes and no...the change in distribution with the PDO's/AMO leads to an overall swing of about .4C which is why it's really only meaningful to measure (smoothed) peak to peak or trough to trough. No matter how anyone tries to twist it around we have no indications of any more than about .5C/century of warming...and there are still other factors we're not sure of (like we're pretty sure we probably would have been warming some anyway after the LIA).
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Post by trbixler on Apr 3, 2009 22:30:23 GMT
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Post by FurryCatHerder on Apr 3, 2009 22:46:25 GMT
Furry, are you suggesting that rain is a reduction of the overall water vapor in the atmosphere? That it is continually declining? No, because that would be stupid, and I'm not stupid. I think you need to look at the curve of temperature versus mass of water per unit volume at 100% relative humidity. There is an effective upper bound on how much water the atmosphere can hold, and it's driven primarily by diurnal changes in temperature. Usually when it exceeds saturation anywhere the problem is immediately resolved in the form of precipitation, fog or dew. It's not like the atmosphere can stay saturated ... Uh, the atmosphere doesn't behave like a liquid where more of something can just keep being added. If you throw a bucket of water in the air, the air doesn't magically hold onto it ...
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Post by jimg on Apr 4, 2009 0:34:13 GMT
Furry, look at you statements.
There is an effective upper bound on how much water the atmosphere can hold, and it's driven primarily by diurnal changes in temperature.
Usually when it exceeds saturation anywhere the problem is immediately resolved in the form of precipitation, fog or dew.
That is exactly what I said. If the air temp is 80 F at 100% humidity, then a cold air front comes in, dropping the temp to 60F. The air will be super-saturated (temporarily) and as you said, precipitation will result.
...to be continued
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Post by ron on Apr 4, 2009 0:56:48 GMT
Don't cold air fronts kind of move (a lot of) the air with them? So the saturated air gets pushed out to a large extent?
In fact, at least in the NH, aren't high pressure, fair weather areas more often than not preceeded by cold fronts?
Aren't there different types of cold fronts, some that move over and/or under air masses?
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Post by tilmari on Apr 4, 2009 18:06:18 GMT
This I sent today to climatesceptics at Yahoo:
Hi all,
When the Jupiter year 06.1987-05.1999 was nearing its end, I made a lot of calculations, and 3th April 1999 I wrote into my diary: “Now I’m sure that the 170-230 year cycle with a mean value of about 200-202 years, has in the data 1762-1999 a value of about 212 years, which means that the length of the cycle 23 will be 13.6 years instead of the “normal” value in the 20th century of 10.3 years. The Gleissberg cycle also has its minimum length of 72 years in 2005 which supports this conclusion.”
Nasa wrote recently: (“Deep Solar Minimum”). “Quiet suns come along every 11 years or so…. The current solar minimum is part of that pattern. In fact, it’s right on time. ‘We’re due for a bit of quiet –and here it is,’ says Dean Pesnell. But is it supposed to be this quiet? In 2008, the sun set the following records:
A 50-year low in solar wind pressure: Measurements by the Ulysses spacecraft reveal a 20% drop in solar wind presuure since the mid-1990’s.”
Remark the similarity with the Livingstone-Penn results.
Nasa continues: “A 12 year low in solar irradiance: … the sun’s brightness has dropped … a whopping 6% at extreme UV wavelengths since the solar minimum of 1996. A 55-year low in solar radio wavelengths… Some researchers believe that the lessening of radio emissions is an indication of weakness in the sun’s global magnetic field.”
In the latest Energy & Environment (Vol 20 No. 1 2009) I repeat, what I said on the 1st October 2008:
“The Sun’s ability to produce sunspots has since July been so small, that it is very much in line with what Livingston-Penn suggests – that sunspots may vanish by 2015. This would mean another Maunder Minimum; and the cycle 24 may may be even lower than the Dalton cycles. In practice this means that we may have to wait until 2010 for the active onset of cycle 24. We will see hardly any burst of sunspots in 2008 – only these specks that vanish as soon as they appear. 2009 would be a year of very slow growing of cycle 24.” Then I take the issue of the TSI and its record low drop to near 1365 Watts/m2. No solar constant indeed.
But now the newest analysis:
If we count as decent spots only those that have lasted more than 3 days, the cycle 24 has showed thus far 4 such ones:
6 days in 11.-16. October 2008, 8 days from 30. October to 6. November, 8 days in 10.-17. November and 5 days in 9.-13. January 2009.
In March there appeared only one sunspot group in 06.-07.03. and it belonged to the old cycle 23. The size was only 20 ppm. The last sunspot group reaching 50 ppm appeared 11.01.2009. The sunspot number was 0.7.
Sunspot number has been below 2 in October and November 2007, in July, August, September and December 2008 plus in January, February and March 2009. 100 years ago it is very probably that these 9 months would have been regarded as spotless. With this guesstimate we have after June 2008 had only 2 months with spot(s): October and November 2008.
During the previous cycle change 22/23 in 1996 there were only two months with SSN below 2 (September and October 1996).
The yearly spot value of 2007 was already only 7.6 which is below the previous minimum in 1996 (with 8.6). The value dropped to 2.6 in 2008 and the smoothed value at the moment is also 2.2 (September 2008). (A year ago it was 5.9.) We must go to the year 1913 to find a lower smoothed value (1.5). The August 2008 value means that the cycle 23 has at least a length of 12.3 years.
There have been only 3 cycles since 1749 longer than the cycle 23, the cycle 4 (1784-1798) just before the Dalton minimum, the cycle 6 (1810-1823 or the second of the Dalton cycles) and cycle 9 (1843-1856) that began the series of 5 Jovian cycles and a cool climate in 1856-1913 (sometimes called the Damon minimum). But there are no indications that we have yet seen the bottom of this minimum.
Using as criteria the part per million that the spot groups occupied the cycle 24 has overrided 50 ppm only in 12. October, 2.-4. November and 11.-13. November. March 2009 was the 4th month in row that has not have any sizeble spots. This situation prevailed also from June to September in 2008. There were 6 spotless months during the 1798 minimum, that began the Dalton minimum. Below 2 went 10 months in 1796-1800. Now we have already 9 of them in 2007-2009 (and 2 in 1996).
Considering that Livingstone has got a value from cycle 24 in January 2009 that shows that the magnetic power of the spots, that began to drop at least in 1990, has continued its linear drop leading to the spots vanishing in 2014 or 2015 plus that the Ap index had a new sizable drop in 2008 plus that the TSI continues to go below all measurements since 1979 when the satellite measurements began, we can't wait for any rapid rise for the cycle 24. This means also that the cycle will be low.
Autocorrelation of the sunspots since 1760 gives the highest correlation as 210 years. The Dalton minimum began in 1798, so I make a comparison looking 210 years back just to the beginning of the Dalton minimum.
The yearly sunspotnumbers of 1796-1797 were 16 and 6.4, the corresponding values for 2006-2007 were 15 and 7.6.
The monthly values for 11.1797-12.1798 compared to 01.2008-02.2009 (the greatest correlation) (month spotnumber / month spotnumber adjusted-to-1-AU-10.7cm-flow):
1797: / 2008: 11 ..6 / 01 ..3.4 71 12 ..3 / 02 ..2.1 69 1798: / 2008: 01 ..2 / 03 ..9.3 72 02 ..4 / 04 ..2.9 70 03 12 / 05 ..2.9 69 04 ..1 / 06 ..3.1 68 05 ..0 / 07 ..0.5 68 06 ..0 / 08 ..0.5 67 07 ..0 / 09 ..1.1 67 08 ..3 / 10 ..2.9 67 09 ..2 / 11 ..4.1 67 10 ..2 / 12 ..0.8 66 1798: / 2009: 11 12 / 01 ..1.5 67 12 10 / 02 ..1.4 68 1799: / 2009: 01 ..2 / 03 ..0.7 02 13 / 03 22 / 04 ..8 / 05 ..8 /
The yearly value for 1799 was 6.8.
Adding the previous minimum 1995-1998 yearly values to these:
1796 16 / 1995 18 / 2006 15 1797 ..6 / 1996 ..9 / 2007 ..8 1798 ..4 / 1997 22 / 2008 ..3 1799 ..7 / 1998 64 / 2009 thus far 1.2
Are we going below Dalton with the cycle 24?
************************** And then the temps. **************************
Hadcrut3 temperature values here on Earth: ================================= (baseline 1961-1990)
Global, ground-based:
2001 0.41 2002 0.46 2003 0.47 2004 0.45 2005 0.48 2006 0.42 2007 0.40 2008 0.33
last 12 months (03.2008-02.2009): 0.36
cooling from 2005 to last 12 months 0.12 degrees C
Oceans, buyos (SST):
2001 0.34 2002 0.38 2003 0.41 2004 0.38 2005 0.38 2006 0.34 2007 0.28 2008 0.25
last 12 months (03.2008-02.2009): 0.27
cooling from 2003 to last 12 months 0.14 degrees C
UAH, satellite (lower troposhere, 1-2 km) ===============================
2001 0.20 2002 0.31 2003 0.28 2004 0.20 2005 0.34 2006 0.26 2007 0.28 2008 0.05
last 12 months (03.2008-02.2009): 0.11
cooling from 2005 to last 12 months 0.23 degrees C
Sodankylä in Finnish Lapland (degrees C) =================================
2001 -0.5 2002 -0.5 2003 0.4 2004 0.4 2005 1.5 2006 0.6 2007 0.8 2008 0.5
last 12 months (04.2008-03.2009): 0.3
cooling from 2005 to last 12 months 1.2 degrees C (arctic!)
Mauna Loa CO2 annual increase (parts per million) =======================================
2001 1.6 2002 2.6 2003 2.3 2004 1.6 2005 2.5 2006 1.7 2007 2.1 2008 1.6
Helsinki 2009, placement since 1910 =============================
January -2.8 degrees C, 34/100 (warmest 1930) February -3.6 degrees C, 31/100 (warmest 1990) March -0.9 degrees C, 35/100 (warmest 2007)
CET (Central England) last 351 years, 2009 placement ==========================================
January 3.0 degrees C, 209/351 (60% of Jan’s warmer) February 4.1 degrees C, 171/351 (49% of Feb’s warmer) March 7.0 degrees C, 50/351 (14% of March’s warmer) Timo Niroma
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Post by vukcevic on Apr 4, 2009 19:59:09 GMT
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Post by Belushi TD on Apr 4, 2009 20:51:11 GMT
Furry, the atmosphere behaves EXACTLY like a liquid. A gas is a liquid that is less dense. The same equations are used to describe the behavior of a liquid and a gas.
You throw a bucket of mercury (very dense) into a lake (significantly less dense) , it will sink to the bottom, just like your tossed bucket of water (very dense compared to the air) will fall to the ground.
You take something that is about the same density as air and emit it, it will mix just fine.
Belushi TD
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Post by sigurdur on Apr 4, 2009 22:21:50 GMT
tilmari May I use your so well written response on this thread on another site?
You have really hit the nails on the heads.....thank you.
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Post by tacoman25 on Apr 4, 2009 22:50:34 GMT
Socold, I'll try this one more time. Yes or no, do you believe the variable distribution of CO2 in the atmosphere will effect the total rate of heat transfer through the atmosphere? Yes or no Because some effects which have a significant effect over short time periods don't have a significant effect over long time periods (and vice versa). For example ENSO affects the temperature a lot over a single year. A strong el nino will make a very warm year, or a strong la nina year will make a very cool year. But over say 30 years the el ninos and la ninas largely come in equal number and cancel out therefore dampening their effect on a multi-decadal time scale. Actually, depending on ocean phases (PDO), either El Nino or La Nina can dominate over 30 year periods, which of course effects temperature trends. For example, from 1946-76, negative ENSO (La Nina) conditions dominated positive ENSO (Nino) 2 to 1. From 1977-2007, positive ENSO dominated negative ENSO 2 to 1. So it would be false to assume ENSO/PDO cycle do not have an effect on multi-decadal time scales.
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Post by tilmari on Apr 5, 2009 8:54:44 GMT
tilmari May I use your so well written response on this thread on another site? You have really hit the nails on the heads.....thank you. That's OK, in fact the more people know the actual figures, we can hope the more they are sceptical about catastrophic predictions based only on some computer-aided models that have not had any reality check. Timo
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Post by trbixler on Apr 5, 2009 13:11:42 GMT
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Post by gridley on Apr 6, 2009 15:02:54 GMT
I don't know what that is. Well, you could try taking an introductory course in electronics, thermodynamics, controls, or fluid mechanics. Or you could look up "parallel circuits" for the specific aspect I'm asking about. Anything there ring a bell? My degree is merely mechanical engineering, not climate science, but I got to the point by junior year where I could do parallel circuits (or equivalent systems) in my sleep. Was it not part of your studies in... what areas of technical knowledge do you have?
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Post by gridley on Apr 6, 2009 15:20:42 GMT
I don't suppose you have a link that doesn't involve paying for content? I'm interested, but I can't say I'm that interested. :-) I am not an expert in computer modeling (though I do deal with it on a regular basis at work), but shouldn't a control model of a dynamically stable system produce a cyclical output? Or is that what you mean by "stable climate"? Also, isn't it true that in a complex system one can often accurately model short-term behavior with a lower-order formula? Thus a uniform distribution could, over the short term, mimic a variable distribution with 'reasonable' accuracy, while failing to predict long-term behavior? The equation is from here: www.agu.org/journals/gl/v025/i014/98GL01908/GEOPHYSICAL RESEARCH LETTERS, VOL. 25, NO. 14, PAGES 2715–2718, 1998 New Estimates of Radiative Forcing Due to Well Mixed Greenhouse Gases Gunnar Myhre et al Models work as follows. Models are constructed with the physics as known, but they are tuned within the uncertainties of the observations to produce a stable evolution. ie. such that a model that is run for 20 years with constant CO2, constant solar etc. will produce a stable climate that approximates to earth's climate. In other words, a control experiment is created. Model are then run again with a perturbation such as a gradual increase in CO2, or a volcano or a change in the solar constant to see what would happen. The theory is that if the "electric insulation analogue" effect were important then it would be approximately equally important in the control experiment as in the perturbation experiment with CO2 rising. So if you were to modify the CO2 in the control experiment to match the real variability of CO2, and if you were to do the same in the perturbation run, then the perturbation run would diverge the same amount from the control run because the variability was similar. Since CO2 is quite a stable gas, then this sounds reasonable to me. If, for example, we were to consider ozone though (which is another greenhouse gas), ozone is an unstable gas and is created and destroyed in different parts of the atmosphere in different ways. Furthermore, as the climate warms due to greenhouse gases and as cities grow, near surface ozone levels rise. But the converse effect of greenhouse gases is that the stratosphere cools, and this reduces amounts of ozone there. The reduced stratospheric ozone lets through more UV which means that the stratospere cools more, and reduces ozone a bit more. So it would be a less safe assumption to assume ozone were always well mixed. Indeed many of the models separately model the effects of ozone creation and destruction.
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Post by jimg on Apr 6, 2009 17:10:02 GMT
Gridley. I had to go back and read your original post on the electrical analogy, but I'll give it a shot.
In electrical circuits, if two or more resistances are placed in parallel, the total resistance is then the inverse of the sum of the inverses. ie, 1 / (1/r-1 + 1/r-2 +1/r-3....).
In the GHG world, this would mean that more IR is passed (not absorbed) than would be due to any one concentration area.
(Do I have the analogy correct?).
I don't believe this would apply as the GHG does not present a resistance to the passage of photons. If the conditons are right, the molecule may absorb, or remove, a photon from the IR flux leaving the background. It may then re-emit a photon of equal or lesser value in any direction.
The Greenhouse theory says that since 50% of those photons will be sent back from whence they came, this will reduce the rate at which energy is lost or add energy to the emitter (earth), making the earth warmer.
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