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Post by handyman on Apr 28, 2011 21:50:54 GMT
It was around 4pm when the 1974 Xenia tornado struck. Now, I have little fear of tornadoes that occur in daylight because I can see them. At night, or when things become unclear due to rain wrapping, that's a different story.
A few years back I purchased a weather radio. It's 1 for 2 on tornado warnings right now. Missed the first tornado warning the same week I bought it because the NOAA transmitter was taken offline by an earlier storm that day.
It seemed that, starting with the 1974 tornado, there were several years, lasting into the early 80's, that tornado warnings were much more frequent than the norm. So what you are saying about the weather the next 4-5 years seems right, if solar-forced weather repeats itself about every 36 years. There were very few tornado warnings between the mid-80's through the late '00's.
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Post by scpg02 on Apr 28, 2011 22:17:01 GMT
It was around 4pm when the 1974 Xenia tornado struck. Now, I have little fear of tornadoes that occur in daylight because I can see them. At night, or when things become unclear due to rain wrapping, that's a different story. A few years back I purchased a weather radio. It's 1 for 2 on tornado warnings right now. Missed the first tornado warning the same week I bought it because the NOAA transmitter was taken offline by an earlier storm that day. It seemed that, starting with the 1974 tornado, there were several years, lasting into the early 80's, that tornado warnings were much more frequent than the norm. So what you are saying about the weather the next 4-5 years seems right, if solar-forced weather repeats itself about every 36 years. There were very few tornado warnings between the mid-80's through the late '00's. I don't normally watch the news but happened to catch a report on FOXNews this morning. I expected the usual blame on AGW but no, the head of NOAA said it was just spring and normal for this time of year. Then the reporter went on to add that they had done some research and these types of events have been decreasing over the last 30 years. |
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Post by AstroMet on Apr 29, 2011 0:26:11 GMT
It was around 4pm when the 1974 Xenia tornado struck. Now, I have little fear of tornadoes that occur in daylight because I can see them. At night, or when things become unclear due to rain wrapping, that's a different story. A few years back I purchased a weather radio. It's 1 for 2 on tornado warnings right now. Missed the first tornado warning the same week I bought it because the NOAA transmitter was taken offline by an earlier storm that day. It seemed that, starting with the 1974 tornado, there were several years, lasting into the early 80's, that tornado warnings were much more frequent than the norm. So what you are saying about the weather the next 4-5 years seems right, if solar-forced weather repeats itself about every 36 years. There were very few tornado warnings between the mid-80's through the late '00's. Yes, we've seen fewer of these major tornado events since 1950 but the wider numbers of tornadoes, like the F1 and F2 -rated tornadoes have been increasing in frequency. Astrometeorologically, what has been noticeable are the configurations. These storms were generated within three days after maximum lunar declinations. This happened in April 1974 too. The most recent maximum southern Lunar declination occurred April 21, during the Moon's perigee phase, then the Moon crossed the equator April 28. These lunar maximums and their effects on our atmospheric tides are always present at stormy outbreaks, many of them violent weather according to the seasons they occur. |
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Post by thermostat on Apr 29, 2011 2:22:19 GMT
Magellan, The short answer is that I have access to the literature when I am online on my academic server at the lab. I'm not on that server right now. I can only suggest that when you are at your lab that you open your computer and provide us with credible literature. Thank you once again in advance. Sigurdur, I went back to the literature as requested and found this key paper: "Understanding Recent Stratospheric Climate Change. JOURNAL OF CLIMATE. 15 APRIL 2009." I think this paper is most relevant to the present discussion. Also, and even more relevant, I found this recent paper; "An update of observed stratospheric temperature trends" JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 114, D02107, doi:10.1029/2008JD010421, 2009 For interested forum members, this second 2009 publication is a key reference. This is the 2009 summary of where we are in understanding stratospheric cooling. Here is their summary, "Temperature changes in the lower stratosphere show cooling of 0.5 K/decade over much of the globe for 1979–2007" more completely; "An updated analysis of observed stratospheric temperature variability and trends is presented on the basis of satellite, radiosonde, and lidar observations. Satellite data include measurements from the series of NOAA operational instruments, including the Microwave Sounding Unit covering 1979–2007 and the Stratospheric Sounding Unit (SSU) covering 1979–2005. Radiosonde results are compared for six different data sets, incorporating a variety of homogeneity adjustments to account for changes in instrumentation and observational practices. Temperature changes in the lower stratosphere show cooling of 0.5 K/decade over much of the globe for 1979–2007, with some differences in detail among the different radiosonde and satellite data sets. Substantially larger cooling trends are observed in the Antarctic lower stratosphere during spring and summer, in association with development of the Antarctic ozone hole. Trends in the lower stratosphere derived from radiosonde data are also analyzed for a longer record (back to 1958); trends for the presatellite era (1958–1978) have a large range among the different homogenized data sets, implying large trend uncertainties. Trends in the middle and upper stratosphere have been derived from updated SSU data, taking into account changes in the SSU weighting functions due to observed atmospheric CO2 increases. The results show mean cooling of 0.5–1.5 K/decade during 1979–2005, with the greatest cooling in the upper stratosphere near 40–50 km. Temperature anomalies throughout the stratosphere were relatively constant during the decade 1995–2005. Long records of lidar temperature measurements at a few locations show reasonable agreement with SSU trends, although sampling uncertainties are large in the localized lidar measurements. Updated estimates of the solar cycle influence on stratospheric temperatures show a statistically significantsignal in the tropics (30N–S), with an amplitude (solar maximum minus solar minimum) of 0.5 K (lower stratosphere) to 1.0 K (upper stratosphere). I think the JOURNAL OF GEOPHYSICAL RESEARCH paper presented above is an important paper. Check it out for yourself if you have questions. |
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Post by sigurdur on Apr 29, 2011 2:39:27 GMT
Thermostat:
Thank you. You indicate that the 2nd paper is more pertinent than the 1st. Being I am going to have to buy this from the library, would I be more satisfied buying both of them?
Or is the 2nd one credible enough?
Thanks again.
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Post by sigurdur on Apr 29, 2011 2:41:49 GMT
Also, Was the size of the atmosphere taken into account in deriving the temperature trend of the strat in the above paper? From my understanding, the size plays a part in the temperature of the Strat as the pressure differential changes the perimiters of the Strat itself.
The diff of the atmosphere is from the effect of the solar wind/mag field etc.
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Post by sigurdur on Apr 29, 2011 2:45:55 GMT
I moved your reponse and link to the trop warming/strat cooling thread Thermostat.
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Post by thermostat on Apr 29, 2011 3:07:32 GMT
Thermostat: Thank you. You indicate that the 2nd paper is more pertinent than the 1st. Being I am going to have to buy this from the library, would I be more satisfied buying both of them? Or is the 2nd one credible enough? Thanks again. Sigurdur, The question of whether stratopheric cooling is occurring or not is central to the present discussion. I suggest that obtaining access to a university library system would be helpful. But, regardless, if asked which publication is most significant, I would say "An update of observed stratospheric temperature trends" JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 114, D02107, doi:10.1029/2008JD010421, 2009 |
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Post by thermostat on Apr 29, 2011 3:17:37 GMT
Thermostat: Thank you. You indicate that the 2nd paper is more pertinent than the 1st. Being I am going to have to buy this from the library, would I be more satisfied buying both of them? Or is the 2nd one credible enough? Thanks again. Sigurdur, I suggest you figure how to get access a university library system. That's where the scientifc substance in question is found. |
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Post by codetalker on Apr 29, 2011 5:26:08 GMT
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Post by glc on Apr 29, 2011 7:56:19 GMT
Thermostat (#1368) Re: Strat Cooling Though the figures cited in the study are probably accurate the situation in the stratosphere is not a straightforward as is implied. This is one of the (very few) issues on which I agree with Magellan. All the cooling in the lower stratosphere has immediately followed the 2 major volcanic eruptions. On each of these occasions there has been a sharp upward spike followed by a precipitous drop in temperature. There was a step down in temperature following El Chichon (1982) and a further step down following Pinatubo (1991). There has been very little cooling since. It's a bit out of date, but the first graph in this link illustrates the point www.scscertified.com/lcs/docs/Tropotemptrends.pdf |
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Post by glc on Apr 29, 2011 8:33:02 GMT
Further to my previous post (#1375) This is an exchange between Gavin Schmidt and Roy Spencer (RealClimate 2004): Roy W. Spencer says:
10 Dec 2004 at 1:53 PM
1. The stratosphere does NOT have a positive lapse rate…it is negative. A positive lapse rate is one in which temperature decreases with height. That’s why it’s called a “lapse” rate.
Response: Thanks for pointing out the slip. Fixed it. – gavin
2. The answer to the original question depends on time and space scales involved…if it is referring to global trends in recent decades, then you didn’t really answer the question: the lower stratosphere has cooled in recent decades primarily due to ozone depletion, while the troposphere has warmed (presumably) from the enhanced greenhouse effect.
Response: Fair point. The observed lower stratosphere trend is mainly due to decreasing ozone. Further up, and over the longer term, greenhouse gas changes are likely to be dominant. – gavin www.realclimate.org/index.php/archives/2004/12/why-does-the-stratosphere-cool-when-the-troposphere-warms/ So Schmidt and Spencer were agreed that ozone depletion was responsible for the decline in LS temperatures. Here's a plot of global ozone levels from wiki: en.wikipedia.org/wiki/File:TOMS_Global_Ozone_65N-65S.pngNote the drop in the early 1980s - and then another one in the early 1990s. Coincidence?? |
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Post by magellan on Apr 30, 2011 4:12:48 GMT
Further to my previous post (#1375) This is an exchange between Gavin Schmidt and Roy Spencer (RealClimate 2004): Roy W. Spencer says:
10 Dec 2004 at 1:53 PM
1. The stratosphere does NOT have a positive lapse rate…it is negative. A positive lapse rate is one in which temperature decreases with height. That’s why it’s called a “lapse” rate.
Response: Thanks for pointing out the slip. Fixed it. – gavin
2. The answer to the original question depends on time and space scales involved…if it is referring to global trends in recent decades, then you didn’t really answer the question: the lower stratosphere has cooled in recent decades primarily due to ozone depletion, while the troposphere has warmed (presumably) from the enhanced greenhouse effect.
Response: Fair point. The observed lower stratosphere trend is mainly due to decreasing ozone. Further up, and over the longer term, greenhouse gas changes are likely to be dominant. – gavin www.realclimate.org/index.php/archives/2004/12/why-does-the-stratosphere-cool-when-the-troposphere-warms/ So Schmidt and Spencer were agreed that ozone depletion was responsible for the decline in LS temperatures. Here's a plot of global ozone levels from wiki: en.wikipedia.org/wiki/File:TOMS_Global_Ozone_65N-65S.pngNote the drop in the early 1980s - and then another one in the early 1990s. Coincidence?? Spencer also discussed the stratosphere in his blog. He said the major volcanoes affected the stratosphere profoundly, and not just by reducing ozone. "Presumably" is a polite way of saying it is not a given. Try going to Spencer's blog and look up what he thinks about it 7 years later; he does NOT agree LT warming is due to the "enhanced" greenhouse effect. There is no evidence to support it, and MM10 shot down Santer08 in flames.  Where is the CO2 signal in all this? It is so small it cannot be measured if it exists at all, let alone the "enhanced" greenhouse effect, unless that has been revised after the fact like everything else AGW. |
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Post by thermostat on May 1, 2011 1:17:14 GMT
Magellan,
I must apologize for the delay. I recently asserted that scientists have observed Stratospheric cooling consistent with predictions. You requested that I provide some support and I lamely said I can only get into the library when I am at the lab.
Anyway, next day, I got into the library and looked into this specific subject. I found that a useful recent investigation on temperature variation in the Stratosphere over recent years is; "An update of observed stratospheric temperature trends" Randel et al 2009. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 114.
This is a very thorough analysis of the subject of recent stratospheric cooling. The authors write...
"Temperature changes in the lower stratosphere show cooling of
0.5 K/decade over much of the globe for 1979–2007, with some differences in detail among the different radiosonde and satellite data sets."
As described at length in this excellent paper, analysis of Stratosperic temperatures is an interesting, ongoing science.
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Post by bsattu on May 1, 2011 14:41:15 GMT
Watching NAT Geo this morning, I found that the carbon dioxide was so high in the atmosphere that it caused an ice age, snow ball earth. I thought it caused global warming. Now I am really confused. Carbon dioxide over 5000ppm, are we not in the 300's. Now its saying the sulfur dioxide made the snowball earth warm up. Were are not the cause of so called climate change. Its May and its chilly still, I am moving south, because I love the warmth.
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