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Post by commonsense on Sept 4, 2011 20:51:57 GMT
I was enjoying my retirement, thank you. By the way, I'm learning quite a bit on this thread. I still think that a grand minimum is not probable, and that even if it does occur, it won't change things too terribly much, perhaps a temporary few tenths of a degree C. We're warming up, and transient factors, such as volcanoes and grand minimums, are just bumps in the road. Actually, if we do go into a grand minimum, the temp decline will prob me more than a few tenth of a degree C. This will have profound effects on food supply, and that will be the driving cause of disruption throughout global society. Justsomeguy provided a link to an estimate. It's from 2001, so its a bit dated. Do you have anything that contradicts the estimate? www.sciencemag.org/content/294/5549/2149.short"We examine the climate response to solar irradiance changes between the late 17th-century Maunder Minimum and the late 18th century. Global average temperature changes are small (about 0.3° to 0.4°C) in both a climate model and empirical reconstructions." |
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Post by sigurdur on Sept 4, 2011 21:02:32 GMT
commonsense:
I was referring to just that paper. Note the temp decrease was between 1 and 2C in the NH, where most of the worlds food is grown. Also happens to be where most of the worlds people live as well.
The paper also has a flaw, but can be overlooked. They assume that TSI dropped substantially during the period of study, when in fact newer reconstructions indicate that the drop was marginal at best.
This points to something else as the driver of the temperature drop. Personally, I lean towards the potential drop in solar wind, which allows GCR to bombard us. It also seems the jet stream moves quit dramatically during periods of low sun activity. The combination of these things results in much more variable NH weather, and as such is noted by humans.
The paleo record of around where I live shows a much more than 2.0C drop in temps. Not a good thing for food production at all.
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Post by justsomeguy on Sept 4, 2011 21:52:38 GMT
The jetstream movement and the arctic oscillation changes would be scary for a planet needing to feed a few billion more mouths in the next 50 years. As for dated, I can find much more recent scholarship on the Maunder generally, that author is the one who predicted jetstream movement. See this paper for example: www.mps.mpg.de/projects/sun-climate/papers/uvmm-2col.pdfFocus on Figure 6 and 8, where we have the highest TSI in the recent past during the 20th Century warming - but it is dropping fast now. |
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Post by sigurdur on Sept 4, 2011 22:06:59 GMT
justsomeguy:
Thank you for the link. I did a quick read, this one will take longer to read again slowly and digest. I see that they have broken the TSI by band, I have not read this type of analysis before. This analysis raises a few questions......very interesting.
Thank you again.
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Post by julianb on Sept 9, 2011 8:39:26 GMT
A read through this paper now awaiting publication, will show why TSI is THE only consideration for temperature, apart from the slight increase in distribution of heat between day lit and night hemispheres caused by GHG's, and they only flatten the profile. theendofthemystery.blogspot.com/2010/11/venus-no-greenhouse-effect.html#commentsI know some of you will dismiss it out of hand, but read through all the responses to see how his arguments stand up to criticism. |
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Post by trbixler on Sept 9, 2011 14:04:43 GMT
Not sure if Maunder is in store but probably cooling. "Stunning Revelation From Santer et al. Study: Confirms Insignificant & Immaterial Warming By Year 2100"  Using 17 years (204 months) worth of data through the end of July 2011, the plot on the left reveals that global warming since August 1994 is rather modest and non-existent since 1998. The linear trend from this 17-year span indicates that global temperatures will be only 0.85°C higher by January 1, 2100. The light blue fitted curve suggests that global temperatures are actually moving towards a cooling period, not a warming. The grey fitted curve for CO2 keeps to a linear path ("business as usual") it has long had. Let's identify what human CO2 impacts (past, present and future) have had on the climate per this 17-year period: This 17-year gold-standard, blessed by the holier than thou team of Santer et cohorts, basically confirms that human CO2 emissions have had little, if any, impact on global temperatures. This 17-year span confirms that climate models based on the myopic CO2-"science" are spectacularly wrong. This 17-year span confirms that future global warming will at most be modest. This 17-year data confirms what skeptics have been saying for the last 17 years: runaway positive feedback is a fantasy and future global warming is unlikely to be catastrophic. "Note to readers: The linear trend that produces 0.85°C by 2100 is not a prediction. Actual global temperatures may be higher or lower. No one knows for sure. Most importantly, as this 17-year evidence indicates, current climate models are completely clueless as to future temperatures." www.c3headlines.com/2011/09/stunning-revelation-from-santer-et-al-study-confirms-insignificant-immaterial-warming-by-year-2100.html |
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Post by dontgetoutmuch on Sept 9, 2011 21:14:40 GMT
JulianB
I looked at your link to TSI, but the article in question dealt with a discussion about Venus's high temperatures being caused by atmospheric pressure rather then a runaway greenhouse effect.
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Post by sigurdur on Sept 10, 2011 2:19:07 GMT
JulianB I looked at your link to TSI, but the article in question dealt with a discussion about Venus's high temperatures being caused by atmospheric pressure rather then a runaway greenhouse effect. Try it again. I just clicked on it and the link goes to the graph. And this graph is something I have been stateing for quit some time. One has to look at all the avail data, and it is very evident we have not warmed for approx 15 years now. |
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Post by commonsense on Sept 10, 2011 3:12:21 GMT
A read through this paper now awaiting publication, will show why TSI is THE only consideration for temperature, apart from the slight increase in distribution of heat between day lit and night hemispheres caused by GHG's, and they only flatten the profile. theendofthemystery.blogspot.com/2010/11/venus-no-greenhouse-effect.html#commentsI know some of you will dismiss it out of hand, but read through all the responses to see how his arguments stand up to criticism. The paper makes an elementary error. Venus is far more reflective than Earth. The albedo of Venus is 0.65, while earth's albedo is 0.357. Thus, Venus does NOT absorb more energy from the sun than the Earth does. Thus, your paper proves the greenhouse effect. |
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Post by trbixler on Sept 10, 2011 3:37:41 GMT
A read through this paper now awaiting publication, will show why TSI is THE only consideration for temperature, apart from the slight increase in distribution of heat between day lit and night hemispheres caused by GHG's, and they only flatten the profile. theendofthemystery.blogspot.com/2010/11/venus-no-greenhouse-effect.html#commentsI know some of you will dismiss it out of hand, but read through all the responses to see how his arguments stand up to criticism. The paper makes an elementary error. Venus is far more reflective than Earth. The albedo of Venus is 0.65, while earth's albedo is 0.357. Thus, Venus does NOT absorb more energy from the sun than the Earth does. Thus, your paper proves the greenhouse effect. Apparently you did not read the article and the responses. "This point is fundamental to exposing the incompetence behind the consensus, which insists upon treating the surface of the planet as a blackbody emitter (that is, using the Stefan-Boltzmann equation, "corrected" by "albedo" or not, as it suits their purpose), even though any second-year physics student should know you can only replace an actual body by an equivalent blackbody when the only energy interaction the body has with the rest of the universe is electromagnetic radiation; and the surface of the Earth (or any planet with an atmosphere) does not fit that requirement (since its atmosphere intervenes between it and outer space, and that atmosphere transfers energy by convection and conduction as well as by radiation, scattering the latter all and sundry along the way). In short, you have to draw a shell around the whole Earth-plus-atmosphere system to use the Stefan-Boltzmann equation, and any radiation coming out of that shell, just like any radiation entering it, is part of the thermodynamics of the atmosphere, unavoidably." |
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Post by commonsense on Sept 10, 2011 3:42:11 GMT
Not sure if Maunder is in store but probably cooling. Using 17 years (204 months) worth of data through the end of July 2011, the plot on the left reveals that global warming since August 1994 is rather modest and non-existent since 1998. The linear trend from this 17-year span indicates that global temperatures will be only 0.85°C higher by January 1, 2100. The light blue fitted curve suggests that global temperatures are actually moving towards a cooling period, not a warming. The grey fitted curve for CO2 keeps to a linear path ("business as usual") it has long had. Let's identify what human CO2 impacts (past, present and future) have had on the climate per this 17-year period: This 17-year gold-standard, blessed by the holier than thou team of Santer et cohorts, basically confirms that human CO2 emissions have had little, if any, impact on global temperatures. This 17-year span confirms that climate models based on the myopic CO2-"science" are spectacularly wrong. This 17-year span confirms that future global warming will at most be modest. This 17-year data confirms what skeptics have been saying for the last 17 years: runaway positive feedback is a fantasy and future global warming is unlikely to be catastrophic. "Note to readers: The linear trend that produces 0.85°C by 2100 is not a prediction. Actual global temperatures may be higher or lower. No one knows for sure. Most importantly, as this 17-year evidence indicates, current climate models are completely clueless as to future temperatures." www.c3headlines.com/2011/09/stunning-revelation-from-santer-et-al-study-confirms-insignificant-immaterial-warming-by-year-2100.htmlTruly an analysis that attempts to hide the data rather than enlighten. Note the phrase "at least". That doesn't make 17 years a gold standard, but a bare minimum. Plus note that they didn't bother to analyse the data at all, but made a simplistic linear extrapolation. Obviously ENSO must be included in the analysis. They ignored it. The data is weighted heavily to El Nino in the early years and La Nina in the later years, for example, obviously skewing the results. Had the authors been honest, they would have adjusted for that. The use ot the phrase "gold standard" also smacks of dishonesty. No, it is obvious that the authors are either dishonest or inept. |
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Post by trbixler on Sept 10, 2011 3:50:29 GMT
Not sure if Maunder is in store but probably cooling. Using 17 years (204 months) worth of data through the end of July 2011, the plot on the left reveals that global warming since August 1994 is rather modest and non-existent since 1998. The linear trend from this 17-year span indicates that global temperatures will be only 0.85°C higher by January 1, 2100. The light blue fitted curve suggests that global temperatures are actually moving towards a cooling period, not a warming. The grey fitted curve for CO2 keeps to a linear path ("business as usual") it has long had. Let's identify what human CO2 impacts (past, present and future) have had on the climate per this 17-year period: This 17-year gold-standard, blessed by the holier than thou team of Santer et cohorts, basically confirms that human CO2 emissions have had little, if any, impact on global temperatures. This 17-year span confirms that climate models based on the myopic CO2-"science" are spectacularly wrong. This 17-year span confirms that future global warming will at most be modest. This 17-year data confirms what skeptics have been saying for the last 17 years: runaway positive feedback is a fantasy and future global warming is unlikely to be catastrophic. "Note to readers: The linear trend that produces 0.85°C by 2100 is not a prediction. Actual global temperatures may be higher or lower. No one knows for sure. Most importantly, as this 17-year evidence indicates, current climate models are completely clueless as to future temperatures." www.c3headlines.com/2011/09/stunning-revelation-from-santer-et-al-study-confirms-insignificant-immaterial-warming-by-year-2100.htmlTruly an analysis that attempts to hide the data rather than enlighten. Note the phrase "at least". That doesn't make 17 years a gold standard, but a bare minimum. Plus note that they didn't bother to analyse the data at all, but made a simplistic linear extrapolation. Obviously ENSO must be included in the analysis. They ignored it. The data is weighted heavily to El Nino in the early years and La Nina in the later years, for example, obviously skewing the results. Had the authors been honest, they would have adjusted for that. The use ot the phrase "gold standard" also smacks of dishonesty. No, it is obvious that the authors are either dishonest or inept. Really, an astute observation of the team. "Comments On The New Paper “Separating Signal And Noise In Atmospheric Temperature Changes: The Importance Of Timescale” By Santer Et Al 2011" From Santer " We compare global-scale changes in satellite estimates of the temperature of the lower troposphere (TLT) with model simulations of forced and unforced TLT changes. While previous work has focused on a single period of record, we select analysis timescales ranging from 10 to 32 years, and then compare all possible observed TLT trends on each timescale with corresponding multi-model distributions of forced and unforced trends. We use observed estimates of the signal component of TLT changes and model estimates of climate noise to calculate timescale-dependent signal-to-noise ratios (S/N). These ratios are small (less than 1) on the 10-year timescale, increasing to more than 3.9 for 32-year trends. This large change in S/N is primarily due to a decrease in the amplitude of internally generated variability with increasing trend length. Because of the pronounced effect of interannual noise on decadal trends, a multi-model ensemble of anthropogenically-forced simulations displays many 10-year periods with little warming. A single decade of observational TLT data is therefore inadequate for identifying a slowly evolving anthropogenic warming signal. Our results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature." pielkeclimatesci.wordpress.com/2011/09/07/comments-on-the-new-paper-separating-signal-and-noise-in-atmospheric-temperature-changes-the-importance-of-timescale-by-santer-et-al-2011/ |
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Post by sigurdur on Sept 10, 2011 4:14:45 GMT
trblixer:
And even that 17 years is potentially not long enough. The trend of the noise shows that in reality it is closer to 60 years, and we aren't even close to that length of time with any reliable data.
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Post by icefisher on Sept 10, 2011 4:26:14 GMT
Truly an analysis that attempts to hide the data rather than enlighten. Note the phrase "at least". That doesn't make 17 years a gold standard, but a bare minimum. Plus note that they didn't bother to analyse the data at all, but made a simplistic linear extrapolation. Obviously ENSO must be included in the analysis. They ignored it. The data is weighted heavily to El Nino in the early years and La Nina in the later years, for example, obviously skewing the results. Had the authors been honest, they would have adjusted for that. The use ot the phrase "gold standard" also smacks of dishonesty. No, it is obvious that the authors are either dishonest or inept.
Santer statistics are the gold standard of IPCC's position.
One can certainly question Santer and his statistics but its a sword that cuts two ways that is if you have any common sense you will see that instantly.
All that is going on here is trying to buy a few more years. Its clear already that that .85 warming per century is not going to alarm anybody an that is where we are at as far as model validation goes. Heck if you take 31 years its still only about 1.4. Thats also outside the range of the IPCC.
The problem here is if global warming hasn't been disproven it is even in worse shape about getting proven. Santer wishes to couch it as if the models had already been validated. "Reverse findings". What findings?
As I see it using Santer's standards, we need 4 years to disprove AGW and 17 years to prove it.
You don't establish skill by guessing the cause of a past 17 year period of warming. Anybody that does survey work understands that. Its like flying over the arctic and finding 4 dead polar bears when you weren't looking for polar bears. Its a finding of convenience. You need replicates to establish anything from that.
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Post by trbixler on Sept 10, 2011 14:20:28 GMT
trblixer: And even that 17 years is potentially not long enough. The trend of the noise shows that in reality it is closer to 60 years, and we aren't even close to that length of time with any reliable data. Hmmm 60 years. Maybe its the CO2 cycle.  landscheidt.wordpress.com/ |
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