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Post by jimcripwell on Aug 7, 2009 20:18:57 GMT
stevenotsteve writes "Not only does history show that it cools during a grand solar minimum but the last 30 years also shows that it warms during a grand solar maximum."
Thanks stevenotsteve. I had forgotten that part.
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Post by socold on Aug 7, 2009 21:56:09 GMT
Wow UAH actually rose 0.4C from June to July?
That's half the global warming of the 20th century!
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Post by snowguy716 on Aug 7, 2009 23:14:02 GMT
I think Joe Bastardi over at Accuweather.com makes a good point when he says that this El Niño is a "reactive" one, in that the trade winds and SSTs are simply a reaction to preexisting atmospheric conditions that are driving the El Niño, not unlike the '06-07 Niño that Jim Hansen thought was going to be 97/98 reincarnated. Joe had been saying from the get go that it was a reactive one and would fall apart early and sure enough it fell apart beginning in January.
So, it doesn't surprise me that global temperatures spiked in July, because the atmospheric conditions are already in place for El Niño... the SSTs are just lagging in this case.
In contrast, the La Niñas of the past two years were more proactive.. driven by massive upwelling of cold water from below that in turn strengthened the trade winds and created atmospheric Cold Episode conditions. That's why it took a while for temps to really drop (to Jan. '08).
Either way, I think the strongly positive SOI for July will really limit the intensity of this El Niño, but we're in uncharted territory. Never before in a forming El Niño have we seen such a strong reversal to actual La Niña SOI conditions during that summer.
The models are now responding and cooling their forecasts a bit and the Niño 3.4 region did cool last week... and upper ocean heat content is falling. This pig'll be cooked before we even get the heat going. And it'll probably mean a nasty winter for the east coast this winter.
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Post by glc on Aug 7, 2009 23:27:40 GMT
Not only does history show that it cools during a grand solar minimum but the last 30 years also shows that it warms during a grand solar maximum. What was that trace gas everyone was talking about a while back? CO something or other.
So "history" shows us does it? Could you perhaps provide a link to this history. Could you also provide justification for your comment which implies that the last 30 years were a "solar maximum". It's my understanding that the peak sunspot count occurred in ~1958.
Thanks
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Post by nautonnier on Aug 8, 2009 0:00:46 GMT
I think Joe Bastardi over at Accuweather.com makes a good point when he says that this El Niño is a "reactive" one, in that the trade winds and SSTs are simply a reaction to preexisting atmospheric conditions that are driving the El Niño, not unlike the '06-07 Niño that Jim Hansen thought was going to be 97/98 reincarnated. Joe had been saying from the get go that it was a reactive one and would fall apart early and sure enough it fell apart beginning in January. So, it doesn't surprise me that global temperatures spiked in July, because the atmospheric conditions are already in place for El Niño... the SSTs are just lagging in this case. In contrast, the La Niñas of the past two years were more proactive.. driven by massive upwelling of cold water from below that in turn strengthened the trade winds and created atmospheric Cold Episode conditions. That's why it took a while for temps to really drop (to Jan. '08). Either way, I think the strongly positive SOI for July will really limit the intensity of this El Niño, but we're in uncharted territory. Never before in a forming El Niño have we seen such a strong reversal to actual La Niña SOI conditions during that summer. The models are now responding and cooling their forecasts a bit and the Niño 3.4 region did cool last week... and upper ocean heat content is falling. This pig'll be cooked before we even get the heat going. And it'll probably mean a nasty winter for the east coast this winter. The tradewinds blow the top surface of the Pacific away from the Americas toward Indonesia actually raising the sea levels in the western Pacific. The tradewinds are strongest when the equatorial convective cells (Hadley Cells) are strongest - needing warm sea temperatures especially around Indonesia. The effect is that as the surface water is pushed away from the western coasts of the Americas cold water wells up replacing it in the eastern Pacific - a La Nina. When the sea surface temperatures decline so do the Hadley Cells. Indeed, the convection has declined so much this year that the jetstream that sits towards the polar side of the Hadley cells is closer to the equator than normal - the reason for the poor summer in Canada the North of the USA and in the UK. As the convection in the cells weakens so the inflowing air modified by the Coriolis effect - the tradewinds - decline. Without the westward pressure of the tradewinds on the sea surface the hot surface water that was being blown toward Indonesia 'slops' back in a 'Kelvin Wave' and the sea temperatures in the eastern Pacific increase as the warm surface water flows back - an El Nino. As the sea surface temperatures increase the convection increases, the tradewinds increase and the warm surface water gets blown back again. Hence it is an oscillation. However, it would be interesting to see a disspationate calculation of whether there is actually a real change in the Ocean Heat Content. There is certainly a large change in the distribution of heat and of course the rapid loss of heat into the atmosphere briefly raises atmospheric temperatures and this extra heat in the atmosphere is rapidly lost to space. So the El Nino could actually be seen as a cooling event for the planet and in some respects a La Nina could be considered as storing heat in 'the (Steve's) pipeline' in the western Pacific. So the winds resulting from atmospheric convection drive the ocean surface heat distribution which drives the atmospheric convection which drives the...... So the question is - why all the excitement over 'El Nino years' or 'La Nina Years' when it is just a redistribution of heat? And indeed when the El Nino's are net losses of ocean heat content to space?
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Post by snowguy716 on Aug 8, 2009 0:24:20 GMT
Thanks for the very informative post... that really makes sense that the cool equatorial waters would ultimately pull the jetstream further south over the region (hence the cool summer in the U.S./Canada but not necessarily so elsewhere).
I also agree that El Niño/La Niña are just redistributions of heat. The earth is not in perfect equilibrium, though. Different cycles can mean the earth stores up or radiates more heat over a longer period of time (like with the PDO).
The reason people look for information on El Niños and La Niñas around here is because they have pretty severe impacts on our weather, which impacts the economy, especially in winter since we rely on good snows for business. (northern Minnesota.. where we just finished our coldest July on record and also coldest May-July period).
If you look back at all of the moderate to strong warm episodes of the past 50 years, you'll see that impact is strongest in northern Minnesota and North Dakota with drastically warmer winter temps.
Summer time El Niños on the other hand tend to bring cooler weather in late spring/early summer and more frequent torrential rains, as was the case in 1987.
Another argument supporting what you've written is that after large volcanic eruptions, El Niños tend to form, not because of a warming planet, but because the northern latitudes are getting so much less energy due to blockage of sunlight by aerosols and dust particles. This likely forces the jetstream south and weakens the trade winds, thus allowing an El Niño to form. Look at the winter of '91/92 after Pinatubo or '82/83 after El Chinchon.
I believe the strong ocean driven La Niña of 2007/08 was driven by the heat in the Arctic in summer '07. All of that melting ice had to have some effect when it sinks. Could the response have been massive upwelling of cold water off South America?
But like a pendulum, the earth reacts to these things a little too strongly and then there is a counter reaction. This current El-Niño is a reaction to the La Niñas and subsequent cooling of the planet during the last 2 years.
Sorry the post is all over the place... it's just a collection of thoughts and ideas. Thanks again Nautonnier.
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Post by woodstove on Aug 8, 2009 1:26:06 GMT
Not only does history show that it cools during a grand solar minimum but the last 30 years also shows that it warms during a grand solar maximum. What was that trace gas everyone was talking about a while back? CO something or other. So "history" shows us does it? Could you perhaps provide a link to this history. Could you also provide justification for your comment which implies that the last 30 years were a "solar maximum". It's my understanding that the peak sunspot count occurred in ~1958. Thanks Solanki 2004: cc.oulu.fi/~usoskin/personal/nature02995.pdf(Article is entitled "Unusual activity of the Sun during recent decades compared to the previous 11,000 years")
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Post by socold on Aug 8, 2009 1:35:08 GMT
Solanki 2003: "This comparison shows without requiring any recourse to modeling that since roughly 1970 the solar influence on climate (through the channels considered here) cannot have been dominant. In particular, the Sun cannot have contributed more than 30% to the steep temperature increase that has taken place since then, irrespective of which of the three considered channels is the dominant one determining Sun-climate interactions: tropospheric heating caused by changes in total solar irradiance, stratospheric chemistry influenced by changes in the solar UV spectrum, or cloud coverage affected by the cosmic ray flux." www.mps.mpg.de/homes/natalie/PAPERS/warming.pdf
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Post by sigurdur on Aug 8, 2009 2:32:11 GMT
Solanki 2003: "This comparison shows without requiring any recourse to modeling that since roughly 1970 the solar influence on climate (through the channels considered here) cannot have been dominant. In particular, the Sun cannot have contributed more than 30% to the steep temperature increase that has taken place since then, irrespective of which of the three considered channels is the dominant one determining Sun-climate interactions: tropospheric heating caused by changes in total solar irradiance, stratospheric chemistry influenced by changes in the solar UV spectrum, or cloud coverage affected by the cosmic ray flux." www.mps.mpg.de/homes/natalie/PAPERS/warming.pdfThat paper is already outdated socold.
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Post by snowguy716 on Aug 8, 2009 4:48:18 GMT
Not only does history show that it cools during a grand solar minimum but the last 30 years also shows that it warms during a grand solar maximum. What was that trace gas everyone was talking about a while back? CO something or other. So "history" shows us does it? Could you perhaps provide a link to this history. Could you also provide justification for your comment which implies that the last 30 years were a "solar maximum". It's my understanding that the peak sunspot count occurred in ~1958. Thanks Solanki 2004: cc.oulu.fi/~usoskin/personal/nature02995.pdf(Article is entitled "Unusual activity of the Sun during recent decades compared to the previous 11,000 years") Interestingly, the Minneapolis/Fort Snelling temperature record shows a pretty strong correlation to solar irradiance. Temperatures rose fast from 1820-1835 (the first 15 years of record), which also coincided with the climb out of the Dalton Minimum. From 1840-1875 the temperature in Minneapolis plummeted 2.5˚F, just as the solar irradiance fell during the same period. The winters were particularly harsh during the 1850s and '60s. Then came something very similar to 1997/98. A strong El Niño event in 1877/78 brought the warmest winter to the region on record, blowing any modern records away by a long shot. We're talking winter temps that were consistently 1.5 to 2.5 standard deviations above normal from late November through early April. The climate was then about 3˚F warmer for 5 years after the 1877 event. A cold period came back in 1883 and lasted until 1889 before temperatures rose to the 1820-2008 mean and hovered around that until 1915. In one year, 40 years of cooling were erased and we haven't seen anything like it since. Temperatures then began to rise again in 1917/18 to about 1-1.5˚F above the 1820-2008 mean which held from 1930-1959. During that period, the warmest years occurred from 1930-1935, 1946-49, and again from 1952-1959... the latter being the warmest string of years in history to that time. Temperatures were then about 0.5-1.0˚F below the 1820-2008 mean during the 1960s and early 1970s. Another warming trend began in the mid '70s, and peaked in the late '80s and early '90s with cooler temps in the mid 90s. The period of 1978-1993 was not as warm as the 1930-1959 period.. it was 0.2-0.5˚F cooler. Then came the Super Niño of 1998 and temperatures spiked 1.5-2˚F to about 3˚F above the long term mean and remained there until 2007. 2008, the most recently available year, was 0.1˚F above normal, thus ending the string of very warm years. I would expect if we are headed into a quiet solar period that Minneapolis would see a cooling climate.
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Post by magellan on Aug 8, 2009 5:28:30 GMT
Solanki 2003: "This comparison shows without requiring any recourse to modeling that since roughly 1970 the solar influence on climate (through the channels considered here) cannot have been dominant. In particular, the Sun cannot have contributed more than 30% to the steep temperature increase that has taken place since then, irrespective of which of the three considered channels is the dominant one determining Sun-climate interactions: tropospheric heating caused by changes in total solar irradiance, stratospheric chemistry influenced by changes in the solar UV spectrum, or cloud coverage affected by the cosmic ray flux." www.mps.mpg.de/homes/natalie/PAPERS/warming.pdfAs the Solanki paper mentions Willson vs Lean throughout, it is fitting to mention this: ACRIM-gap and TSI trend issue resolved using a surface magnetic flux TSI proxy modelwww.agu.org/pubs/crossref/2009/2008GL036307.shtmlThe ACRIM-gap (1989.5-1991.75) continuity dilemma for satellite TSI observations is resolved by bridging the satellite TSI monitoring gap between ACRIM1 and ACRIM2 results with TSI derived from Krivova et al.’s (2007) proxy model based on variations of the surface distribution of solar magnetic flux. ‘Mixed’ versions of ACRIM and PMOD TSI composites are constructed with their composites’ original values except for the ACRIM gap, where Krivova modeled TSI is used to connect ACRIM1 and ACRIM2 results. Both ‘mixed’ composites demonstrate a significant TSI increase of 0.033%/decade between the solar activity minima of 1986 and 1996, comparable to the 0.037% found in the ACRIM composite. The finding supports the contention of Willson (1997) that the ERBS/ERBE results are flawed by uncorrected degradation during the ACRIM gap and refutes the Nimbus7/ERB ACRIM gap adjustment Fröhlich and Lean (1998) employed in constructing the PMOD. ” This finding has evident repercussions for climate change and solar physics. Increasing TSI between 1980 and 2000 could have contributed significantly to global warming during the last three decades [Scafetta and West, 2007, 2008]. Current climate models [Intergovernmental Panel on Climate Change, 2007] have assumed that the TSI did not vary significantly during the last 30 years and have therefore underestimated the solar contribution and overestimated the anthropogenic contribution to global warming.
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Post by radiant on Aug 8, 2009 6:38:42 GMT
Not only does history show that it cools during a grand solar minimum but the last 30 years also shows that it warms during a grand solar maximum. What was that trace gas everyone was talking about a while back? CO something or other. So "history" shows us does it? Could you perhaps provide a link to this history. Could you also provide justification for your comment which implies that the last 30 years were a "solar maximum". It's my understanding that the peak sunspot count occurred in ~1958. Thanks If you look at the years around 1958 you can see that from about 1930 to 1970 although there is the large 1958 spike those years taken together dont appear as consistantly high as the overall higher period that is progressively building for the last part of the century. If you had various moving averages it would be clearer as to exactly what is happening either way. I also note that the most intense period of solar radiation on earth is june 21st and it is generally warmer 2 months later. Similarly it is most low around december 21st and is generally most cold 2 months later. Depending where you live there is a lag anyway.
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Post by glc on Aug 8, 2009 10:27:34 GMT
Interestingly, the Minneapolis/Fort Snelling temperature record shows a pretty strong correlation to solar irradiance. Temperatures rose fast from 1820-1835 (the first 15 years of record), which also coincided with the climb out of the Dalton Minimum. From 1840-1875 the temperature in Minneapolis plummeted 2.5¢ªF, just as the solar irradiance fell during the same period. The winters were particularly harsh during the 1850s and '60s.I don't think there is a strong correlation but it's not easy to see as the plots do not use the same time axis. I think, though, you have picked out selected periods when there does appear to be a relationship. Two other things: 1. The Lean reconstruction uses TSI which I'm now being told (by JimC et al) is not the correct measure for solar activity. I can understand why they say this. TSI has only varied by ~1 w/m2 over the past 150 years, i.e. less than 0.1%, which implies (by S-B) that temperatures changes due to TSI will only have varied by 0.025% or ~0.07 deg [assuming average temp of 15 deg C (288K)]. 2. The Lean reconstruction is now almost certainly wrong. Even Lean thinks so. The early TSI estimates are now thought to be too low. Bob Tisdale covers the issue on his blog. bobtisdale.blogspot.com/2009/03/ipcc-20th-century-simulations-get-boost.htmlNote how recent reconstructions vary much less than Lean et al (and Doug Hoyt's). Interestingly Bob makes the very valid point that this puts the IPCC "detection and attribution" reconstruction of 20th century climate into considerable doubt. It's just worth considering that a non-varying sun is actually more of an inconvenience to the AGW argument than it is to the sceptics.
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Post by glc on Aug 8, 2009 10:52:56 GMT
If you look at the years around 1958 you can see that from about 1930 to 1970 although there is the large 1958 spike those years taken together dont appear as consistantly high as the overall higher period that is progressively building for the last part of the century. If you had various moving averages it would be clearer as to exactly what is happening either way.
I also note that the most intense period of solar radiation on earth is june 21st and it is generally warmer 2 months later.
Similarly it is most low around december 21st and is generally most cold 2 months later. Depending where you live there is a lag anyway.
Ok I understand your point. But the lag here is getting rather long - much longer than previous periods when the sun supposedly correlates with temperature. However, you look at it solar activity didn't peak any later than ~1990/91. Global temperatures have only recently 'flattened' - at best. In terms of sunspot activity, SC23 (the recent one) was fairly average. Every time the troposphere warms this is supposedly a sign that the earth is losing more heat. In which case the earth must have been losing heat since ~1998 and apart from a couple of La Nina episodes it still seems to be pretty toasty.
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Post by radiant on Aug 8, 2009 11:54:13 GMT
If you look at the years around 1958 you can see that from about 1930 to 1970 although there is the large 1958 spike those years taken together dont appear as consistantly high as the overall higher period that is progressively building for the last part of the century. If you had various moving averages it would be clearer as to exactly what is happening either way.
I also note that the most intense period of solar radiation on earth is june 21st and it is generally warmer 2 months later.
Similarly it is most low around december 21st and is generally most cold 2 months later. Depending where you live there is a lag anyway.Ok I understand your point. But the lag here is getting rather long - much longer than previous periods when the sun supposedly correlates with temperature. However, you look at it solar activity didn't peak any later than ~1990/91. Global temperatures have only recently 'flattened' - at best. In terms of sunspot activity, SC23 (the recent one) was fairly average. Every time the troposphere warms this is supposedly a sign that the earth is losing more heat. In which case the earth must have been losing heat since ~1998 and apart from a couple of La Nina episodes it still seems to be pretty toasty. I am assuming there is something else going on in the minimums as for example the atmosphere being smaller and less UV. I just dont know enuf about that to know either way but the atmosphere being smaller or lower seems to me to have huge implications for upper air movement. You say the earth is toasty. Is it? If by toasty you mean it has warmed .74 degree in 100 years it is within experimental error because most of our temperatures have been measured on land and for all other other reasons like urban heat island etc. Then there are the subjective things i know about for example i have a home in NZ and i am living in Finland. Then there is the canadian data from for example wheat boards where temps are much lower. From my point of view having assumed the earth was warming i am left now not knowing what is happening. What do you know about the changes in the earths atmosphere and less UV? Is that common in between solar cycles?
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