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Post by tallbloke on Feb 14, 2009 14:01:57 GMT
glc wants it both ways, he talks about temps recovering from the last la nina but criticises icefisher and I for running a linear trend to this current peak temperature between two la ninas.You didn't run the linear trend between "2 La Ninas". You'd better take a look again at what you and icefisher did. If you want to start in a La Nina period you need to go back to 1999 or 2000. Read it again. I didn't say I did. I said " linear trend to this current peak temperature between two la ninas." Since the 2007-2008 la nina came to an end, temperatures as you say 'recovered', and we are now entering another la nina, temperatures will fall in the coming months. Therefore, the current peak in temperature is the peak between two la ninas.
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Post by Col 'NDX on Feb 14, 2009 21:51:40 GMT
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Post by france on Feb 14, 2009 22:31:01 GMT
About ENSO, a geophysicist I know says these fluctuations happen according to the solar activity. With low solar activity is Nina and opposite with high solar activity is Nino.
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Post by magellan on Feb 15, 2009 4:42:09 GMT
glc wants it both ways, he talks about temps recovering from the last la nina but criticises icefisher and I for running a linear trend to this current peak temperature between two la ninas.You didn't run the linear trend between "2 La Ninas". You'd better take a look again at what you and icefisher did. If you want to start in a La Nina period you need to go back to 1999 or 2000. Read it again. I didn't say I did. I said " linear trend to this current peak temperature between two la ninas." Since the 2007-2008 la nina came to an end, temperatures as you say 'recovered', and we are now entering another la nina, temperatures will fall in the coming months. Therefore, the current peak in temperature is the peak between two la ninas. 2008 was a whopping .009 above 1999 and .014 above 2000. For 2009 it is .071. Where will it be on Jan 1, 2010? Should it be expected to drop like a rock during a cooling period? That appears to be the expectation of warmers to reject the hypothesis of CO2 AGW. By now even during a La Nina year such as 2008 should not even be on the radar. This illustrates the folly of using linear trends to assess non linear data. Posted in another thread:
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Post by glc on Feb 15, 2009 16:35:19 GMT
By now even during a La Nina year such as 2008 should not even be on the radar
Remember that there is a ~0.1% change in TSI between solar max and solar min, so 2008 should be ~0.7 deg cooler than 1999/2000 all other things being equal.
Also, regarding your diagram, why didn't post-1998 temperatures return to pre-1998 levels following the 1998 El Nino.
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Post by icefisher on Feb 15, 2009 21:59:33 GMT
glc wants it both ways, he talks about temps recovering from the last la nina but criticises icefisher and I for running a linear trend to this current peak temperature between two la ninas.You didn't run the linear trend between "2 La Ninas". You'd better take a look again at what you and icefisher did. If you want to start in a La Nina period you need to go back to 1999 or 2000. You could also use 2001 as it was an Enso neutral year starting as a La Nina and ending neutral as 2008 was. Picking 2000 or 1999 you are starting in big la nina years and ending in a neutral year.
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Post by tallbloke on Feb 15, 2009 22:57:40 GMT
By now even during a La Nina year such as 2008 should not even be on the radarRemember that there is a ~0.1% change in TSI between solar max and solar min, so 2008 should be ~0.7 deg cooler than 1999/2000 all other things being equal. Also, regarding your diagram, why didn't post-1998 temperatures return to pre-1998 levels following the 1998 El Nino. Leif Svalgaard reckons around a 0.1C difference between solar max and min. 0.1% of tsi is around 1.36w/m^2 which would equate to around 0.2C/decade. Where does your 0.7C figure come from? For your el nino question, check bobtisdale.blogspot.comStep changes up accompany el ninos, and likely we'll find the same in reverse with la ninas.
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Post by glc on Feb 16, 2009 0:09:17 GMT
Leif Svalgaard reckons around a 0.1C difference between solar max and min. 0.1% of tsi is around 1.36w/m^2 which would equate to around 0.2C/decade. Where does your 0.7C figure come from?My mistake - it should be ~0.07 deg. For your el nino question, check bobtisdale.blogspot.com Step changes up accompany el ninos, and likely we'll find the same in reverse with la ninas.I don't think this holds true for all El Ninos - and I doubt very much it's true for all La Ninas (think 1999/2000), but I need to read the article properly before deciding on it's merit.
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Post by bobtisdale on Feb 16, 2009 21:28:57 GMT
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Post by tallbloke on Feb 16, 2009 23:58:40 GMT
Hi Bob, The SST data for the period when we last had a long negative PDO phase is beset with bucket adjustment and inlet sensor problems (1940-1975) so I guess we'll have to wait to see if downward step changes kick in until we are further into the currently beginning negative phase. It's too noisy at the cycle peak. Thanks for all your detailed work on this stuff. It's a tremendous resource for all us climate speculators. 8-)
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Post by magellan on Feb 17, 2009 0:10:26 GMT
Bob, your opening statement is thus: Agreed, except the actual distance of warming of the surface skin of the water would be <.03mm (much less actually) as LW IR is in the 10-20 micron range, whereas SW radiation penetrates 10's of meters. Absorption coefficient of water can be found here: www.lsbu.ac.uk/water/vibrat.htmlIf you have a source for the physical process by which can explain how a 100 ppm increase in atmospheric CO2 could account for anything measurable in ocean warming I'd appreciate it. There is a lot of arm waiving, but I'd like to see some experimental evidence. Thank you.
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Post by woodstove on Feb 17, 2009 1:24:33 GMT
Bob, your opening statement is thus: Agreed, except the actual distance of warming of the surface skin of the water would be <.03mm (much less actually) as LW IR is in the 10-20 micron range, whereas SW radiation penetrates 10's of meters. Absorption coefficient of water can be found here: www.lsbu.ac.uk/water/vibrat.htmlIf you have a source for the physical process by which can explain how a 100 ppm increase in atmospheric CO2 could account for anything measurable in ocean warming I'd appreciate it. There is a lot of arm waiving, but I'd like to see some experimental evidence. Thank you. Hey Magellan. I always appreciate your posts here. Assuming that the figure you give of possible ocean warming via CO2-emitted LW IR is dead on, couldn't the argument be made that you're falling into the same trap as the AGWers when they over-rely on radiative transfer in some largely static fantasyland, seeming to ignore or miss convection in the atmosphere? That is to say that the ocean surface is constantly shifting, so if the topmost layer is warmed, and milliseconds later there is a new topmost layer, then the heat should get mixed downward. No?
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Post by nautonnier on Feb 17, 2009 2:06:19 GMT
That's what I was thinking - the sea surface is never 'flat' unlike a nicely balanced beaker in a closed environment under an infrared source.
<---------- Look waves, wavelets, ripples, foam, spray - I see a lot of sea
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Post by glc on Feb 17, 2009 9:01:03 GMT
Hey Magellan.
I always appreciate your posts here. Assuming that the figure you give of possible ocean warming via CO2-emitted LW IR is dead on, couldn't the argument be made that you're falling into the same trap as the AGWers when they over-rely on radiative transfer in some largely static fantasyland, seeming to ignore or miss convection in the atmosphere? That is to say that the ocean surface is constantly shifting, so if the topmost layer is warmed, and milliseconds later there is a new topmost layer, then the heat should get mixed downward. No? I'm with Magellan on this one (there's a first - and probably a last). The depth of penetration of LW IR (typically emitted by the atmosphere) is around the thickness of human hair. Why is it any more likely that the 'heated' skin would mix down than it would radiate back into the amosphere - or even increase the rate of evaporation a tiny amount. The 'official' explanation is not that downward IR heats the ocean but that the heated skin layer slows the rate of cooling from the ocean below. This realclimate article is worth a look www.realclimate.org/index.php/archives/2006/09/why-greenhouse-gases-heat-the-ocean/langswitch_lang/sk
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Post by tallbloke on Feb 17, 2009 10:27:14 GMT
Oh No! Groundhog day again. ;D
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