General AGW debate thread

[skierinvermont]

No way in hell can you figure out how much to remove based on ENSO. Lets see some freakin evidence of your claim in how much to remove.

Lets see it. You cannot attibute a certain amount to ENSO because the ONI, or Nino SST, is only part of ENSO, and how the GTA has been affected by each driver and forcings is NOT KNOWN, only that there is a correlation.

ANd...

Your +.06C does not apply after the PDO flip anyway, so its kinda over anyway.

I'm not going to teach you statistics over the internet. Take a college level statistics class or start reading here:

http://en.wikipedia....sis_of_variance

http://www.realclimate.org/index.php/archives/2008/07/global-trends-and-enso/

[BethesdaWX]

Even if you attempt to remove ENSO ( you will do in incorrectly), trending in the AO/NAO, AMO/PDO, changes in GCC which are unknown, Global Volcanism, Global SST's, All have to be accounted for.

Do we know how much to correct for that? No, but we do know those factors HAVE led to warming in the timeframe you're looking at. Not How Much.

[BethesdaWX]

I'm not going to teach you statistics over the internet. Take a college level statistics class or start reading here:

http://en.wikipedia....sis_of_variance

That has nothing to do with removing for ENSO, and how much for each event.

In fact, read the section "assumptions"...there you get it.

[BethesdaWX]

And if you select a period which shows no trend in ENSO, or if you remove the effect of ENSO statistically as many people often do, then the trend since 1998 is around +.08C/decade.

+PDO and strengthening +AMO would account for that even if it was true. Thats only part of the story too.

Again, expected. You cannot remove for ENSO accurately.

[BethesdaWX]

I'm not going to teach you statistics over the internet. Take a college level statistics class or start reading here

http://www.realclima...rends-and-enso/

GISS? Are you that desperate?

Realclimate/skeptical science have these type of issues. Using sunspot numbers/TSI to correlate to global temperatures, instead of the Geomagnetic Flux/10BE which corretales 100%.

Or using GISS instead of UAH/RSS.

Thats where they get their answers.

[nzucker]

I'm not going to teach you statistics over the internet. Take a college level statistics class or start reading here:

Bethesda does have a point: you cannot effectively remove any global oscillation in an independent fashion, since we aren't able to fully comprehend the various interactions between solar, NAO/AO, ENSO/PDO that may in one way or another influence the change in global temperature. Without a doubt, you can make an approximation of what the global temperature trend would be since 1998 without ENSO fluctuation, and you arrive at a figure around .07-.08C; it's important to admit however, that this is an approximation and a reductionist approach in some senses that reflects how humans understand weather patterns by categorizing them, not by how they actually work.

[BethesdaWX]

I have to say, looking at the latest ocean data tells me that El Niño is trying to get a foothold across the Tropical Pacific. What's going to be crucial is whether those cold SSTs over the negative subsurface pocket in the eastern regions keep feeding the La Niña despite how much warmth has built in from Indonesia. We still have the strong trade winds and -PDO configuration that favors a La Niña, but it wouldn't take much at this point given the above-average OHC in the ENSO region to make a reversal in direction.

Obviously, a lot of us East Coast weenies are praying for a weak Niño, so these are good signs.

How quickly we go to Neutral this spring summer will determine alot on the hurricane season.

Also, whether we drop from Weak El Nino to Cold Neutral Next winter in the timeframe, or remain warm, will have implications.

I'm thinking we slowly rise to El Nino this fall before it Quickly Dies off next FEB.

[BethesdaWX]

Bethesda does have a point: you cannot effectively remove any global oscillation in an independent fashion, since we aren't able to fully comprehend the various interactions between solar, NAO/AO, ENSO/PDO that may in one way or another influence the change in global temperature. Without a doubt, you can make an approximation of what the global temperature trend would be since 1998 without ENSO fluctuation, and you arrive at a figure around .07-.08C; it's important to admit however, that this is an approximation and a reductionist approach in some senses that reflects how humans understand weather patterns by categorizing them, not by how they actually work.

Thankyou.

Also take into account the rapid +AMO warming since 1994, and the +PDO for much of that timeframe, and that can account for any remaining warming trend until 2007...which is (coincidently) when any background warming stops..

[nzucker]

How quickly we go to Neutral this spring summer will determine alot on the hurricane season.

Also, whether we drop from Weak El Nino to Cold Neutral Next winter in the timeframe, or remain warm, will have implications.

I'm thinking we slowly rise to El Nino this fall before it Quickly Dies off next FEB.

Having a weak El Niño this fall in a general -PDO pattern would be great news for winter lovers like me...brings to mind cold/snowy winters like 63-64, 68-69, and 69-70.

I doubt the Pacific breaks into a full strong Niño/+PDO regime given how persistent the trades and high SOI as well as the strength of the SST anomalies in the North Pacific, just very clear that there's some feedback between the warm SSTs near the Aleutians and that big Central Pacific/Aleutian ridge that sets the whole longwave North American pattern in motion. We also need to see a defined Kelvin Wave to go over to El Niño, and that doesn't appear to be coming for at least a few weeks, and climatologically wouldn't.

[BethesdaWX]

Having a weak El Niño this fall in a general -PDO pattern would be great news for winter lovers like me...brings to mind cold/snowy winters like 63-64, 68-69, and 69-70.

I doubt the Pacific breaks into a full strong Niño/+PDO regime given how persistent the trades and high SOI as well as the strength of the SST anomalies in the North Pacific, just very clear that there's some feedback between the warm SSTs near the Aleutians and that big Central Pacific/Aleutian ridge that sets the whole longwave North American pattern in motion. We also need to see a defined Kelvin Wave to go over to El Niño, and that doesn't appear to be coming for at least a few weeks, and climatologically wouldn't.

yeah that would be the perfect snow setup for us, although I'm not a cold weather fan at all. I love the Heavy, Wet, Warm snows that coat everything and give me a fantastic workout in shoveing and tree cutting. Cold air is gross.

I could be wrong, but I feel theres no way we go into Strong El Nino, or anything close to it. I could obviously be wrong, but I'd think low end moderate is as high as we can do.

(My personal viewpoint below) Going to go on a rant here.

Thing is, the higher the El Nino, usually the stronger the La Nina afterwards, the climate system responds to changes within the system (atmosphere & oceans) by doing the Opposite to counteract. UNLESS the forcing is outside the climate system (aka, the Sun, GCR, etc), which is where we see a break in the usualy "wave equilibrium" pattern on the planet, and a base influence. Example...... a Huge Volcano erupts...cools the globe. What happens next? GLAAM spikes, El Nino Develops, and the global warms in response.

[nzucker]

yeah that would be the perfect snow setup for us, although I'm not a cold weather fan at all. I love the Heavy, Wet, Warm snows that coat everything and give me a fantastic workout in shoveing and tree cutting. Cold air is gross.

I could be wrong, but I feel theres no way we go into Strong El Nino, or anything close to it. I could obviously be wrong, but I'd think low end moderate is as high as we can do.

(My personal viewpoint below) Going to go on a rant here.

Thing is, the higher the El Nino, usually the stronger the La Nina afterwards, the climate system responds to changes within the system (atmosphere & oceans) by doing the Opposite to counteract. UNLESS the forcing is outside the climate system (aka, the Sun, GCR, etc), which is where we see a break in the usualy "wave equilibrium" pattern on the planet, and a base influence. Example...... a Huge Volcano erupts...cools the globe. What happens next? GLAAM spikes, El Nino Develops, and the global warms in response.

The Earth always tries to balance itself out...that's why we often see record breaking Niñas like 73-74 and 88-89 after strong El Niños. I'd think two strong Niños in three years would violate that balance, but who really knows? Usually when you get a strong La Niña, it makes such an imprint on global SSTs and atmospheric circulations that it's extremely hard to go back towards El Niño, especially a more powerful one. I'm wondering if the fading of the cold surface waters in the western ENSO regions and the strength of the subsurface warmth there might mean we're to go into a west-based weak El Niño with the PDO remaining quite negative and the extensive cold pool in ENSO Region 2 and to its south remaining in place. That would certainly be a tough winter to analog.

Another thing to watch is the solar activity; if we start seeing more CMEs, that might be a support for El Niño. Landscheidt among others believed that bursts in solar activity could be related to the development of ENSO events, so that's something to watch. Lately activity has plateaued some and the trades have returned to the ENSO area, but will that tendency continue into Summer 2011? The unusually deep minimum in solar activity may have strong repercussions down the road in determining what type of ENSO state we see and how the -AO/-NAO pattern stays intact.

[BethesdaWX]

Looking at that Subsurface water, alot of that warmth in the western areas is going to get beaten down to pulp before it even reaches the surface.

Looks like the classic signal of west-central based ENSO, probably has a short lifespan though, in looking at the conformation of the anoms.

Funny though, our recent La Nina was not nearly as strong as the recent El Nino in 2010, but we Outdid the spike, and with more cooling to come in March, not to mention it was the fastest 4 month drop on record.

[nzucker]

Looking at that Subsurface water, alot of that warmth in the western areas is going to get beaten down to pulp before it even reaches the surface.

Looks like the classic signal of west-central based ENSO, probably has a short lifespan though, in looking at the conformation of the anoms.

Funny though, our recent La Nina was not nearly as strong as the recent El Nino in 2010, but we Outdid the spike, and with more cooling to come in March, not to mention it was the fastest 4 month drop on record.

The interesting aspect of the ENSO trends is the cold subsurface pool in the eastern regions that seems to have recently surfaced. NOAAs 3/14 SSTA map showed cold SSTs surfacing in Region 2, which had warmed a lot in February, and that area of cold water seems to be gaining ground in the shallow subsurface despite the warmth spreading as far as 110W from Indonesia. This is almost exactly the opposite of 2008, when the cold waters in the western regions were holding on much better but the eastern area had become almost permanently dominated by warmth. Having a constant cold feed from the Peruvian coastal areas extending deep into the subsurface will certainly help our La Niña hold its ground, especially considering the strong trade winds currently occurring and persisted to continue for the next week. Today's SOI was +26.18, and the last week has seen a solid string of double-digit positive SOI values, with one more trade surge expected to take place on 3/16-17, perhaps sending the SOI once again into the +35 range as it was a few days ago. So you may be correct that much of the subsurface warmth will never see the light of day given the persistent easterlies and the Niñas firm anchoring in the Baja California, Peruvian, and Southern Ocean cold pools, some of which extend deep down into the ocean. There's definitely a strong battle occurring but the La Niña is probably one step ahead in the war.

Given these conflicting ENSO tendencies and model output, I don't think anyone would forecast a moderate/strong ENSO state for Winter 11-12. It seems that most forecasts are centered around weak Niña to neutral, with a few long-range mets like Chuck going for a weak El Niño. That's obviously a good sign for our winter, as we average the most snowfall in weak ENSO states, and I believe this applies to most of the I-95 corridor. I know that NYC has seen highest snowfall in a weak El Niño historically, but two of the East Coast's best winters, 95-96 and 60-61, were weak Niña/negative-neutral years. The famed March 3, 1960 Appalachian/Northeast blizzard and connected cold wave also took place in a negative neutral regime, and a weak Niña in 66-67 led to one of the snowiest winters ever in the NYC northern suburbs and parts of New England. So things are looking good in that respect, coupled with the NAO/PDO cycles being firmly in the negative realm, leading me to believe that next winter holds at least as much promise as the last two have delivered, and perhaps more for the Mid-Atlantic where a strong Niña is difficult with the lack of STJ activity. Interestingly, although the January 1996 blizzard was formed by the polar jet, the STJ did become active later that winter to create a very snowy February and March, and in some places April. Also, we'll have the cooler global temperatures on our side and perhaps better arctic ice conditions pending what goes down this summer. But I digress... (Sorry, I already miss winter and am in withdrawal till gardening season starts in April)

[BethesdaWX]

The interesting aspect of the ENSO trends is the cold subsurface pool in the eastern regions that seems to have recently surfaced. NOAAs 3/14 SSTA map showed cold SSTs surfacing in Region 2, which had warmed a lot in February, and that area of cold water seems to be gaining ground in the shallow subsurface despite the warmth spreading as far as 110W from Indonesia. This is almost exactly the opposite of 2008, when the cold waters in the western regions were holding on much better but the eastern area had become almost permanently dominated by warmth. Having a constant cold feed from the Peruvian coastal areas extending deep into the subsurface will certainly help our La Niña hold its ground, especially considering the strong trade winds currently occurring and persisted to continue for the next week. Today's SOI was +26.18, and the last week has seen a solid string of double-digit positive SOI values, with one more trade surge expected to take place on 3/16-17, perhaps sending the SOI once again into the +35 range as it was a few days ago. So you may be correct that much of the subsurface warmth will never see the light of day given the persistent easterlies and the Niñas firm anchoring in the Baja California, Peruvian, and Southern Ocean cold pools, some of which extend deep down into the ocean. There's definitely a strong battle occurring but the La Niña is probably one step ahead in the war.

Given these conflicting ENSO tendencies and model output, I don't think anyone would forecast a moderate/strong ENSO state for Winter 11-12. It seems that most forecasts are centered around weak Niña to neutral, with a few long-range mets like Chuck going for a weak El Niño. That's obviously a good sign for our winter, as we average the most snowfall in weak ENSO states, and I believe this applies to most of the I-95 corridor. I know that NYC has seen highest snowfall in a weak El Niño historically, but two of the East Coast's best winters, 95-96 and 60-61, were weak Niña/negative-neutral years. The famed March 3, 1960 Appalachian/Northeast blizzard and connected cold wave also took place in a negative neutral regime, and a weak Niña in 66-67 led to one of the snowiest winters ever in the NYC northern suburbs and parts of New England. So things are looking good in that respect, coupled with the NAO/PDO cycles being firmly in the negative realm, leading me to believe that next winter holds at least as much promise as the last two have delivered, and perhaps more for the Mid-Atlantic where a strong Niña is difficult with the lack of STJ activity. Interestingly, although the January 1996 blizzard was formed by the polar jet, the STJ did become active later that winter to create a very snowy February and March, and in some places April. Also, we'll have the cooler global temperatures on our side and perhaps better arctic ice conditions pending what goes down this summer. But I digress... (Sorry, I already miss winter and am in withdrawal till gardening season starts in April)

Agreed. Next winter could be crazy huge for the Entire East Coast, I'm also thinking Weak El Nino next winter, reversing to Neutral by FEB/MAR/APR. La Nina has 1 up in the battle because its still around lol...but the aspect of balance plays here, ENSO likely plays a much smaller role for the next 2 yrs.

One thing that caught my eye very quickly, and got me jumping really good, is what the Westerly QBO is trending, and where it could end up by next winter. I don't want to say anything and Jynx it, but take a look youself!!!

[nzucker]

Agreed. Next winter could be crazy huge for the Entire East Coast, I'm also thinking Weak El Nino next winter, reversing to Neutral by FEB/MAR/APR. La Nina has 1 up in the battle because its still around lol...but the aspect of balance plays here, ENSO likely plays a much smaller role for the next 2 yrs.

One thing that caught my eye very quickly, and got me jumping really good, is what the Westerly QBO is trending, and where it could end up by next winter. I don't want to say anything and Jynx it, but take a look youself!!!

Can you link me to some updated QBO data? I see it's gone down some since November, but don't have the latest readings. What is the exciting news? We'd be in great shape if we had a -QBO during a time of solar minimum, as that tends to lead to sudden stratospheric warming which sends the AO/NAO into their favorable negative states. If we got a weak, west-based El Niño (which certainly seems possible given the warmth towards Indonesia in the subsurface and the weakening cold anomalies at the surface in Region 3.4/4), we might see a very favorable winter pattern since El Niño also helps to warm the stratosphere and could work in tandem with the dropping QBO to create a high-latitude blocking pattern like 09-10, except with more cold air available since global temperatures are lower and the El Niño would almost definitely be weaker. Fortunately, with a -QBO/low solar, the SSW usually happens early in the winter, and that's the time when global temperatures might be coldest and lead to a true arctic blast for much of the East Coast. If we could get the STJ working, we might have an ideal winter pattern like 77-78 with an even more extreme NAO unlike the Central Canada block that occurred that time around. A third historic winter would be almost unprecedented for NYC...Central Park did have 50.7" in both 1915-16 and 1916-17, as well as a cold snowy winter in 1917-18, but this would be even more impressive since KNYC had 51.4" in 09-10 and is over 60" this season. The northern suburbs where I live also approached 50" in 08-09 as we jackpotted in the 12/19/08 storm with 8". Can you tell I'm excited?

ENSO may play a smaller role but a weak Niña/weak Niño tends to create a more impressive high-latitude blocking pattern than stronger ENSO events, since the jet tends to be weaker to parallel the ENSO state. Also, the PNA tends is usually much more favorable in these states than in a strong La Niña year like 10-11, where you're almost certain to see the trough shift to the West in February, giving the East a mild end to the winter...we've seen this many times in stronger Niñas like 75-76 and 88-89 where the East starts pretty cold in Dec/Jan and then warms up dramatically for the second half of the winter. This year was even more extreme up here since we had such a brutally snowy and frigid December and January, and then conditions turned placid in February and have been that way since with very little in the way of snowfall. A weaker ENSO state would allow us to see more variation from the PNA, and we'd almost definitely average a +PNA if we get a weak El Niño. One thing I've tended to notice is that the east-based weak Niños tend to be very cold but not as snowy (69-70, 76-77) whereas the west-based events have the best of both worlds (77-78). A weak Niño also seems to be much colder than a strong Niño, perhaps due to the powerful STJ introducing too much warmth in Strong Niños. Even though 2009-10 was in the top 20 coldest winters for the CONUS since records began in the 1890s, there was very little in the way of arctic air. 850s here reached a minimum around -18C in December compared to around -20C on January 24th this year and nearly -25C on January 16, 2009 two winters ago!

[skierinvermont]

Bethesda does have a point: you cannot effectively remove any global oscillation in an independent fashion, since we aren't able to fully comprehend the various interactions between solar, NAO/AO, ENSO/PDO that may in one way or another influence the change in global temperature. Without a doubt, you can make an approximation of what the global temperature trend would be since 1998 without ENSO fluctuation, and you arrive at a figure around .07-.08C; it's important to admit however, that this is an approximation and a reductionist approach in some senses that reflects how humans understand weather patterns by categorizing them, not by how they actually work.

It is not perfect - but there is absolutely no denying the underlying approximate warming trend of around .07-.08C/decade as you said. Instead he insists there is a cooling trend because he selects period with strong -ENSO tendencies.

[nzucker]

It is not perfect - but there is absolutely no denying the underlying approximate warming trend of around .07-.08C/decade as you said. Instead he insists there is a cooling trend because he selects period with strong -ENSO tendencies.

You can't deny that we've still seen some warming since 1998; the combination of sources yields an estimate of .08C/decade compared to IPCC projections of .2C/decade or so. This is reduced if you run it since 2001, and the lowest I've heard is around .04-.05C/decade using an ENSO-corrected analysis of RSS data since 2001. The number should decline some more with 2011 being a relatively cool year globally and the chances remaining high for another Niña in Winter 11-12. I think we both understand that statistical methods can isolate factors for approximate analysis but can never be perfect since they ignore the fact that ENSO is part of an intricate, interwoven climate system which cannot be dissembled piece by piece without losing some of its meaning. I would argue that volcanic eruptions like Pinatubo are more suited for isolation, but even that is not perfect since high-latitude volcanoes can create a +AO tendency and all volcanoes can cause an El Niño to form by changing wind and ozone patterns in the atmosphere...these factors in turn may affect the global temperature trend. In any case, the argument that temperatures have warmed less than expected by the IPCC or Hadley Center holds water when doing ENSO-corrected analysis since either 1998 or 2001, and if you don't correct for ENSO it holds even more water when you do the 1998-2011 trend line, obviously a biased picture but one that may be symbolic in many ways of the transition from +PDO/high solar to -PDO/low solar.

Thoughts on next winter, skier? Have you been following the spreading warmth in the sub-surface? Do you think the -NAO will come back as per decadal/solar tendency if we do see a weak Niña or weak Niño rather than the current strong Niña?

[skierinvermont]

You can't deny that we've still seen some warming since 1998; the combination of sources yields an estimate of .08C/decade compared to IPCC projections of .2C/decade or so. This is reduced if you run it since 2001, and the lowest I've heard is around .04-.05C/decade using an ENSO-corrected analysis of RSS data since 2001. The number should decline some more with 2011 being a relatively cool year globally and the chances remaining high for another Niña in Winter 11-12.

The current La Nina and a potential Nina next year won't affect the underlying warming trend. It will simply require a larger correction to remove the ENSO tendency.

The latest ENSO model runs have ticked colder.

[nzucker]

The current La Nina and a potential Nina next year won't affect the underlying warming trend. It will simply require a larger correction to remove the ENSO tendency.

The latest ENSO model runs have ticked colder.

Again, though, you can only correct to a certain extent; if you believe it's going to be typical to see La Niña after La Niña in our current -PDO/low solar environment, then perhaps a partial correction would be called for? We might want to settle on the average ONI we expect the next decade, -.05 to -.1 seems pretty reasonable to me, and thus allow the global temperature trend to account somewhat for the PDO. When you're early in the -PDO cycle, it's not unusual to see a run of La Niña...48-49, 49-50, 54-55, 55-56, 56-57 were all La Niñas, with only one of the list being weak, and that's only a nine year period! If we think the solar minimum may be enhancing the Niña base state, then perhaps we can expect stretches like that to persist. This will affect the global temperature trend, which will affect how quickly ecosystems and our society need to adapt to climate change, which will affect cost/benefit analysis...you get the idea!

Nice to hear the ENSO models have ticked a bit colder...I'd like a weak La Niña as it ensures cold global temperatures and gives us a great shot at a snowy/cold winter in the East. Lots of sweet analogs to break out if we get into a weak Niña with a -NAO dominating. It would be insane to see something like 95-96 after the past two winters, but it seems the snowy years do come in bunches as the late 50s/60s shows for most of the East Coast cities. No one would have expected a 90" winter with three HECS here in 60-61 after a 28" blizzard in March 1960, but so it was. In any case, I don't think the ENSO models have too much credibility at this point; a smart forecaster would wait until June before making serious predictions, as that's when the 2009-10 Niño started ramping up as did the 2010-11 La Niña. Early spring trends in SSTs mean relatively little as everything tends to be in flux.

[BethesdaWX]

Nzucker, remember that alot of the warming/cooling trends are caused by the PDO/AMO themselves, so Even if the removing of ENSO is somehow correct, the +0.8C is easily accounted for by the +AMO warming, and the +PDO, and the resulting warmer global SST's. With the release of the FEB 2011 anom, we are now in a cooling trend since 2002.

Unfortunately for Skier, the underlying warming trend ends in 2007 as 3 of the past 4 years have average below the decadal mean.

Also, here is the latest QBO data

http://www.esrl.noaa...lation/qbo.data

2010 -16.02 -16.98 -19.68 -23.57 -26.28 -25.05 -9.84 1.45 6.58 10.83 12.16 10.97

2011 9.18 10.05

I'd be surprised if MAR comes in higher, I like the trends. I've been wrong before though.

[BethesdaWX]

Instead he insists there is a cooling trend because he selects period with strong -ENSO tendencies.

Why do you constantly talk BS about me? How desperate are you? I never said anything like that.

You need to get out of the denial you've been in the entire thread. Even if the +.08C since 1998 were correct, the extra warming would be accounted for by +PDO = warming Global SST's, & the growing +AMO throughout the timeframe...to name a few.

Now, show me where you got those numbers from. Because I'm damn sure they are not from UAH or RSS.

NSIDC, GISS, HAD?

[skierinvermont]

Why do you constantly talk BS about me? How desperate are you? I never said anything like that.

You need to get out of the denial you've been in the entire thread. Even if the +.08C since 1998 were correct, the extra warming would be accounted for by +PDO = warming Global SST's, & the growing +AMO throughout the timeframe...to name a few.

Now, show me where you got those numbers from. Because I'm damn sure they are not from UAH or RSS.

NSIDC, GISS, HAD?

Actually it is from UAH. This is what tacoman and zucker and I used when we agreed the underlying ENSO correected trend since 1998 was around +.08C/decade and a little lower than that since 2002. Though it is probably better to use an average of Had+GISS, given the large disagreements about satellite data.

The PDO has had a cooling tendency during the period in question. The AMO has no detectable correlation to global temperatures. And the solar cycle has had a strong cooling effect. Removing all factors and one probably arrives close to the theoretical +.15C/decade warming trend.

[BethesdaWX]

Actually it is from UAH. This is what tacoman and zucker and I used when we agreed the underlying ENSO correected trend since 1998 was around +.08C/decade and a little lower than that since 2002. Though it is probably better to use an average of Had+GISS, given the large disagreements about satellite data.

The PDO has had a cooling tendency during the period in question. The AMO has no detectable correlation to global temperatures. And the solar cycle has had a strong cooling effect. Removing all factors and one probably arrives close to the theoretical +.15C/decade warming trend.

No, absolutely not. You're wrong. The PDO warmed steadily from 1999-2006. AMO has a very signficant effect, as you can read below

http://www.ossfounda...oscillation-amo

What are the impacts of the AMO?

The AMO has affected air temperatures and rainfall over much of the Northern Hemisphere, in particular, North America and Europe. It is associated with changes in the frequency of North American droughts and is reflected in the frequency of severe Atlantic hurricanes. It alternately obscures and exaggerates the global increase in temperatures due to human-induced global warming.

FYI, With the release of FEB 2011, we've now dropped to a cooling trend). Again, cooling trend.

PDO trended up from 1999-2006....again...Up!

Net WARMING since 1999. Wonder why the cooling trend has been so slight since 2002 (cooling as of FEB2011)? Look below. Record breaking +AMO during this timeframe, warming +PDO, El Nino Dominance....Check and Mate bro.

MJO, PDO et al.

http://ggweather.com/enso/mjo.htm

Also.... You are the only one denying the AMO correlation...are you a denier just like we skeptics apparently are?

Its a freakin Carbon Copy of the PDO, and it has a huge correlation (see below)

Listen: The AMO has a large effect on the NH, it doesn't directly correlate to global temperatures since other drivers have larger impacts, but the AMO has a Major Impact on the Arctic, North American Continent, Europe, and Eurasia/Russia.

LOOK

-AMO phase 1963 - 1993

+AMO Phase 1994- Present

You Are making this stuff up right out of your head, and I'm getting weary of setting you straight.

[skierinvermont]

The U.S. does not equal the globe. Moreover, you have simply selected one cycle, when a correlation test can be conducted globally for the last 100 years. There is no detectable effect of the AMO on global temperatures.

The ENSO corrected trend since 1998 is ~.08C/decade. After additionally correcting for the solar cycle (and perhaps also the drop in the PDO) the underlying trend is more like the theoretical value of +.15C/decade.

There is no need to correct for the AMO, as it has not affected global temperatures historically as far as I am aware. If you have a statistical study showing a correlation, go ahead and post it. Moreover, there has been no trend in the AMO in the last 10 years. Even if the AMO has some slight effect, it was causing warming during the 80s and 90s, when it was transitioning from negative to positive.

[BethesdaWX]

The U.S. does not equal the globe. Moreover, you have simply selected one cycle, when a correlation test can be conducted globally for the last 100 years. There is no detectable effect of the AMO on global temperatures.

The ENSO corrected trend since 1998 is ~.08C/decade. After additionally correcting for the solar cycle (and perhaps also the drop in the PDO) the underlying trend is more like the theoretical value of +.15C/decade.

There is no need to correct for the AMO, as it has not affected global temperatures historically as far as I am aware. If you have a statistical study showing a correlation, go ahead and post it. Moreover, there has been no trend in the AMO in the last 10 years. Even if the AMO has some slight effect, it was causing warming during the 80s and 90s, when it was transitioning from negative to positive.

please read carefully

http://www.ossfoundation.us/projects/environment/global-warming/atlantic-multidecadal-oscillation-amo

1) I have now showed you the PDO had a net warming trend from 1999-2006, do you understand this? The PDO itself cools global temps on its own, in addition to its effect on ENSO (which is what gives it dominance). The Warming in the PDO from 1999-2006 had a WARMING impact on the globe.

2) I linked you 3 sources, one is peer reviewed...even AGWers know the AMO influences global temps...NOT correlates directly, as there are other factors. The AMO has a large impact on the US, Canada, The Arctic, Greenland, Europe, Russia, and Asia.....the NH in general.

Do you think the USA is closer to the AMO than Europe, The Arctic, Canada, Russia, Greenland? The AMO impacts the entire NH which will in turn effect the global Anom. The effect the AMO has on the US is nothing compared to that in the Arctic, Europe and Canada.

The AMO went positive in 1994,and warmed steadily until today. Arctic Temps correlate perfectly.

[skierinvermont]

please read carefully

1) I have now showed you the PDO had a net warming trend from 1999-2006, do you understand this? The PDO itself cools global temps on its own, in addition to its effect on ENSO (which is what gives it dominance). The Warming in the PDO from 1999-2006 had a WARMING impact on the globe.

2) I linked you 3 sources, one is peer reviewed...even AGWers know the AMO influences global temps...NOT correlates directly, as there are other factors. The AMO has a large impact on the US, Canada, The Arctic, Greenland, Europe, Russia, and Asia.....the NH in general.

Do you think the USA is closer to the AMO than Europe, The Arctic, Canada, Russia, Greenland? The AMO impacts the entire NH which will in turn effect the global Anom. The effect the AMO has on the US is nothing compared to that in the Arctic, Europe and Canada.

1) Yes the PDO may have had net warming from 1999 to 2006. But that is not the period in question.. the period in question was either 1998-present or 2002-present.. and over both those periods the PDO had a NEGATIVE TREND. It reeks of blatant bias when you randomly select the period 1999-2006 out of your hat.. when that period has nothing to do with the periods we have been discussing. You keep claiming temps have been decreasing 2002-present and I point out that the PDO and ENSO declined over this period so it is not very useful for detecting the underlying AGW trend. In response you say.. 'bu.. bu but the the PDO increased 1999-2006." What the hell does 1999-2006 have to do with our discussion of 2002-present, a period during which both the PDO and the ONI declined, obscuring the underlying AGW warming trend. Switching from 2002-present to 1999-2006 is blatant bias.

2) None of the sources you linked to are peer reviewed. Link to a study which demonstrates a statistical correlation between the AMO and global temperatures.

Even the solar cycle, with its rather small effect of .1C from peak to trough directly correlates. No such correlation can be found for the AMO, so if there is an effect it must be substantially smaller than .1C. You claim that we can't find a correlation because it is obscured by other factors. This reveals a fundamental failure to understand statistical techniques on your part. Even factors with small effects like intra-cycle solar changes correlate to global temperature. The AMO does not in any significant manner.

[BethesdaWX]

I beg you to read carefully, please We'll be able to better debate this if we read everything,and clear up some mis-understandings on what the AMO/PDO have attributed to the 1998-2011 time period.

please read slowly, even if what I write makes you cringe...you'll respond better of you read slowly.

1) The PDO had a net warming from Late 1998 through Early 2006. Factor that in to the 1998 - 2011 period.

2) The AMO (as I will link and explain below), went Positive in 1994, and warmed steadily until today.

3) Remember, we are only 4 years into the "official" -PDO phase....it is young, immature, and will Not Only be Muted somewhat by the +AMO phase, but will less dominant early on, as evidenced by the Recent Strong El Nino in 2010.

4) Do you know why, when we correlate Global temps to The PDO/AMO....the AMO is included? It has the SAME EFFECT the PDO does...Just Minus ENSO!

THE AMO

http://www.ossfounda...oscillation-amo

Data from NOAA

The AMO is an ongoing series of long-duration changes in the sea surface temperature of the North Atlantic Ocean, with cool and warm phases that may last for 20-40 years at a time and a difference of about 1°F between extremes. These changes are natural and have been occurring for at least the last 1,000 years. Source: http://www.aoml.noaa...hod/amo_faq.php Atlantic Multidecadal Oscillation (AMO)

Atlantic Multidecadal Oscillation (AMO) FAQ's

What is the AMO?

The AMO is an ongoing series of long-duration changes in the sea surface temperature of the North Atlantic Ocean, with cool and warm phases that may last for 20-40 years at a time and a difference of about 1°F between extremes. These changes are natural and have been occurring for at least the last 1,000 years.

How much of the Atlantic are we talking about?

Most of the Atlantic between the equator and Greenland changes in unison. Some area of the North Pacific also seem to be affected.

What phase are we in right now?

Since the mid-1990s we have been in a warm phase.

What are the impacts of the AMO?

The AMO has affected air temperatures and rainfall over much of the Northern Hemisphere, in particular, North America and Europe. It is associated with changes in the frequency of North American droughts and is reflected in the frequency of severe Atlantic hurricanes. It alternately obscures and exaggerates the global increase in temperatures due to human-induced global warming.

How does the AMO affect rainfall and droughts?

Recent research suggests that the AMO is related to the past occurrence of major droughts in the Midwest and the Southwest. When the AMO is in its warm phase, these droughts tend to be more frequent and/or severe (prolonged?). Vice-versa for negative AMO. Two of the most severe droughts of the 20th century occurred during the positive AMO between 1925 and 1965: The Dustbowl of the 1930s and the 1950s drought. Florida and the Pacific Northwest tend to be the opposite - warm AMO, more rainfall.

How does the AMO affect Florida?

The AMO has a strong effect on Florida rainfall. Rainfall in central and south Florida becomes more plentiful when the Atlantic is in its warm phase and droughts and wildfires are more frequent in the cool phase. As a result of these variations, the inflow to Lake Okeechobee - which regulates South Florida's water supply - changes by 40% between AMO extremes. In northern Florida the relationship begins to reverse - less rainfall when the Atlantic is warm.

How important is the AMO when it comes to hurricanes - in other words - is it one of the biggest drivers? Or Just a minor player?

During warm phases of the AMO, the numbers of tropical storms that mature into severe hurricanes is much greater than during cool phases, at least twice as many. Since the AMO switched to its warm phase around 1995, severe hurricanes have become much more frequent and this has led to a crisis in the insurance industry.

Does the AMO influence the intensity or the frequency of hurricanes (which)?

The frequency of weak-category storms - tropical storms and weak hurricanes - is not much affected by the AMO. However, the number of weak storms that mature into major hurricanes is noticeably increased. Thus, the intensity is affected, but, clearly, the frequency of major hurricanes is also affected. In that sense, it is difficult to discriminate between frequency and intensity and the distinction becomes somewhat meaningless.

If the AMO (in part) affects hurricanes - what drives the AMO?

Models of the ocean and atmosphere that interact with each other indicate that the AMO cycle involves changes in the south-to-north circulation and overturning of water and heat in the Atlantic Ocean. This is the same circulation that we think weakens during ice ages, but in the case of the AMO the changes in circulation are much more subtle than those of the ice ages. The warm Gulf Stream current off the east coast of the United States is part of the Atlantic overturning circulation. When the overturning circulation decreases, the North Atlantic temperatures become cooler.

Can we predict the AMO?

We are not yet capable of predicting exactly when the AMO will switch, in any deterministic sense. Computer models, such as those that predict El Niño, are far from being able to do this. What is possible to do at present is to calculate the probability that a change in the AMO will occur within a given future time frame. Probabilistic projections of this kind may prove to be very useful for long-term planning in climate sensitive applications, such as water management.

<A name=faq_10>Is the AMO a natural phenomenon, or is it related to global warming?

Instruments have observed AMO cycles only for the last 150 years, not long enough to conclusively answer this question. However, studies of paleoclimate proxies, such as tree rings and ice cores, have shown that oscillations similar to those observed instrumentally have been occurring for at least the last millennium. This is clearly longer than modern man has been affecting climate, so the AMO is probably a natural climate oscillation. In the 20^th century, the climate swings of the AMO have alternately camouflaged and exaggerated the effects of global warming, and made attribution of global warming more difficult to ascertain.

If were to ask ANY met here, I'm sure 99% of them would say the AMO has a significant effect on global temperatures.

The Combined effects of Warmer Global SST's as a result of the +AMO, warming +PDO from Late 1998- 2006, and its effects, are more than enough to account for +.08C increase, even if it were correct. Also note the trending in the NAO/AO, The IOD (indian ocean dipole)...everything is accounted for.

[skierinvermont]

1) The PDO had a net warming from Late 1998 through Early 2006. Factor that in to the 1998 - 2011 period.

This makes zero sense. You are selecting 1999-2006 because the PDO warmed over that period. The correct and unbiased thing to do would be to take the trend from 1998-2011 directly (which is negative) instead of taking 1999-2006 and "factoring that into" 1998-2011.

None of the rest of your posts provides evidence of a correlation between the AMO and global temperatures. Provide me a peer reviewed study which demonstrates a correlation (correlation coeffecients, etc.).

[BethesdaWX]

This makes zero sense. You are selecting 1999-2006 because the PDO warmed over that period. The correct and unbiased thing to do would be to take the trend from 1998-2011 directly (which is negative) instead of taking 1999-2006 and "factoring that into" 1998-2011.

None of the rest of your posts provides evidence of a correlation between the AMO and global temperatures. Provide me a peer reviewed study which demonstrates a correlation (correlation coeffecients, etc.).

1) Dude, I'm selecting 1998-2011 because of your claimed +.08C warming which you never gave evidence to...PDO warmed from 1998-2006, (8 years) then fell negative as we entered the "official" negative base phase in 2007 thru 2009, went positive in 2010, now is back negative. The +.08C stops at 2007, thats the problem with using a weighted mean trend.

NOAA says themselves AMO has a large correlation to the Global temperatures...are you claiming you know more than them?

http://www.aoml.noaa...hod/amo_faq.php

NOAA states the AMO has affected global temps significantly, enough to distort "global warming"

In the 20^th century, the climate swings of the AMO have alternately camouflaged and exaggerated the effects of global warming, and made attribution of global warming more difficult to ascertain.

[VAwxman]

The AMO is essentially the same type of oscillation as the PDO, just on the Atlantic side. Therefore, if one assumes that the PDO can modulate global temperatures, then you have to assume the AMO can as well. The reason it is tougher to correlate, however, is due to the smaller size of the Atlantic, especially versus the Pacific side, which makes the Pacific much more meaningful and easier to correlate. Other factors can more easily override the Atlantic signal.

For folks that do long range forecast, it's a lot like the QBO. If you look at correlations in a vacuum, the signal is hard to see, but it can constructively or destructively intefere with the signal you get when combining everything else.