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pottyprof

Oceanic Debate

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With more research going into exploring our seas and oceans, what discoveries are being made? What are we learning from these discoveries and how do they affect us?

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Hi Folks

For me it is all about the oceans distribution of heat and the complex cycles of mixing and ocean current movements that could be the key to really understanding a lot of the recent global warming phenomena.

Even you do not believe this to be 100% the case, there is a lot we need to discover about the various ocean cycles and their potential impacts on our climate

http://www.drroyspencer.com/

If you take a look at an update on Roy Spencers website arguing the case for the PDO and how it can be seen to have impacted on Global temperatures over the past 100 years you can see a possible mechanism.

As for the here and now, ..... well take a look at this:

AMSRE-SST-Global-and-Nino34-thru-June-17-2010.gif

LA Nina is gearing up nicely.

The rate at which the Nino34 SSTs are falling is striking, as seen in this plot of the SST change rate for that region

AMSRE-SST-Nino34-change-rate-thru-June-17-2010.gif

There has also been a recent increase in global reflectance (as measured by NASA's aqua sattellite), probably due to an increase in global low cloud cover. Here's the graph:

AMSRE-CLW-est-of-CERES-SW-global-60N-60S-thru-June-17-2010.gif

This should begin to show itself in a reduction in global temperature over the second half of 2010.

Guess we'll wait and see.

Y.S

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Hi Folks,

Just as an update to the above post:

UAH_LT_1979_thru_June_10.gif

The globe is still running warm with an anomaly of +0.44 degreed C, but the El-Nino spike has faded and we should be on the way down as La-Nina takes hold.

As ever, time will tell.

Y.S

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Hi All,

I see that the good old CFS is going along with Joe laminate floori's prediction of a second half year temperature plunge .....: Even colder for first few months of next year (we'll see .. ??)

Thought I'd post this in here as it relates to the previous two posts I made.

glbT2mSea.gif

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Well that puts the UK within the warm atlantic anoms over the winter months, that'll sure be better than being snowed in for 4 to 5 weeks again (well those of us in wheelchairs and dependant on transport to get out and about at least!!!).

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I can't quite make out the uk on those maps. How accurate are these?

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I have no idea what T2m stands for but if you look at the same site as YS posted above, but look at the Europe maps, they show colder than normal from August until Feb/March next year.

What does T2m stand for and how does it influence our weather?

http://www.cpc.noaa.gov/products/people/wwang/cfs_fcst/images1/euT2mSea.gif

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I have no idea what T2m stands for but if you look at the same site as YS posted above, but look at the Europe maps, they show colder than normal from August until Feb/March next year.

What does T2m stand for and how does it influence our weather?

http://www.cpc.noaa....s1/euT2mSea.gif

Temperature at 2 metres above ground I suspect.

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Temperature at 2 metres above ground I suspect.

Hi Pete G,

Yes, that is what I believe the T2 to mean.

Y.S

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I'd also think it was a 2m temp J', for some reason it's a global standard but for the oceans?

Oceans will chill ,or warm, air masses that trawl over them so surely it is the surface temp across waters?

Anyhooo's, slowly , but surely, we are getting our act together with the Argo buoys. If we can couple them with deep sea probes in the 'cold currents' then over time we will amass enough data to see the changes currently occuring across the globe. As it is the oceans are even trickier than the atmosphere when it comes to teasing out 'natural' from 'human induced. In the meantime I suggest we use our nous as to what occurs to the oceans when we trap extra heat into the global system.

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Thanks for the answers folks.

Going by those European maps we can expect a colder than average but also dryer than average winter, sounds like an Easterly winter to me.

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http://www.scienceda...00713101412.htm

Had been having a look at the pacific 'warm pool' and came across this.

Grant motivated science at its best. The term "newly detected" being the first clue.

There are are five factors that govern sea level, the first and least important being the rotation of the earth that moves the mass towards the equator but is not relevant because it is pretty much a constant. The second and most notable is the gravitational effect of the moon and sun and that is the most obvious and dramatic- resulting in our tides. The third is wind and this can and does produce measurable differences in regional sea levels as do four and five which are ocean currents and air pressure.

The implication that the warming of the Indo Pacific Warm Pool is partly to be blamed on greenhouse gasses is not verifiable or scientific but pure speculation at best or bull-dust at worst. The use of the words- appear at least partly, likely is amplifying, may aggravate, could have, primarily caused by human-generated increases of greenhouse gases (going out on a limb here), imply that if, may experience, may also etc. further erode any credibility of any scientific worth. They do of course then go on to say that these rises are weather driven and that of course a rise here results in a fall there. See this paper http://palaeoworks.anu.edu.au/pubs/Gaganetal04.pdf to understand better the uncertainties involved. None of the oscillatory ( warm pools and currents as they all are) are not static and change all the time on various and variable time scales. If one is going to blame greenhouse gasses on the warming in one instance what would you then blame in the case of cooling as in the developing La NINA or the now established PDO? All of these are not fully or poorly understood.

Of course they end with the obligatory more research is needed plea. Worthless.

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Just read an interesting article by Atmoz - it's a couple of years old but is well worth a read for those who still think that an oscillation, and in this case the PDO can cause global warming:

http://atmoz.org/blog/2008/08/03/on-the-relationship-between-the-pacific-decadal-oscillation-pdo-and-the-global-average-mean-temperature/

Two stand-out quotes from the above link:

"On Friday I was pointed to another Internet posting that purported to show that the recent warming is due to changes in the PDO. ... I’ve written before that the PDO cannot contribute to global warming for the simple reason that for the ‘classical’ definition of PDO, the trend is removed (eg, at the University of Washington). There will still be variations about the mean, and those variations may mask or enhance the global warming signal in the global mean surface temperature, but it cannot contribute to a trend." [emphasis mine]

There follows a really informative discussion of the relationship between the region wher the PDO is defined, and the warming global oceans.

The second stand-out comment:

"This implies that the mode of variability known as the PDO has the same spatial and temporal characteristics as the mean global surface temperature anomaly. The PDO doesn’t cause global warming, the PDO is global warming. (Insert all the caveats of PCA; statistical relationship not causal, linear, etc.)"

- See the article for the quote in the context of the analysis. What he's done is perform the analysis that extracts the PDO signal on the whole ocean dataset - you get exactly the temperature rise you expect (ie one that matches the observational global temperature timeseries) - the variations, with a warming trend, in the Pacific are merely the local expression of that. The local variations, like PDO or ENSO may tweak global temperature up or down a bit, and this is very noticeable with ENSO, but they fundamentally cannot cause global warming.

sss

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However, most of the people who push the likes of ENSO and the PDO don't actually think that they cause global warming, but rather that their contributions to short-term temperature variability, "tweaking" global temperatures up and down, could have contributed to the warming over the last 50 years. Then to justify that view they need to show that they have shifted towards dominance of phases in recent years that favour a positive "tweak" on global temperatures, and argue that once those phases reverse we may see a cooling. So that article isn't really refuting that common "sceptic" line of thinking, but rather a weakened version of it.

Similarly, if the PDO is capable of introducing short-term variability into mean global temperatures, if the PDO signature follows global temperatures it doesn't immediately follow that "the PDO is global warming". This assumes that there has not been a shift in the mean phase of the PDO towards dominance of a pattern that favours a global temperature that is "tweaked" to the high side. If this assumption turns out to tbe correct, then we can safely reach this conclusion, but not before the assumption is shown to be highly likely to be accurate.

Personally I very much doubt that the PDO has made a significant contribution to global warming in the last few decades, but at the same time, I think some of the arguments that are being used to dismiss the idea are flawed.

ENSO has been discussed in many other areas- I think the general impression has been of ENSO making a small contribution to the warming, but for instance the 2000s were warmer globally than the 1990s despite the mean phase of ENSO falling from positive to near-neutral, so probably not more than a small one.

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However, most of the people who push the likes of ENSO and the PDO don't actually think that they cause global warming, but rather that their contributions to short-term temperature variability, "tweaking" global temperatures up and down, could have contributed to the warming over the last 50 years. Then to justify that view they need to show that they have shifted towards dominance of phases in recent years that favour a positive "tweak" on global temperatures, and argue that once those phases reverse we may see a cooling. So that article isn't really refuting that common "sceptic" line of thinking, but rather a weakened version of it.

Similarly, if the PDO is capable of introducing short-term variability into mean global temperatures, if the PDO signature follows global temperatures it doesn't immediately follow that "the PDO is global warming". This assumes that there has not been a shift in the mean phase of the PDO towards dominance of a pattern that favours a global temperature that is "tweaked" to the high side. If this assumption turns out to tbe correct, then we can safely reach this conclusion, but not before the assumption is shown to be highly likely to be accurate.

Personally I very much doubt that the PDO has made a significant contribution to global warming in the last few decades, but at the same time, I think some of the arguments that are being used to dismiss the idea are flawed.

ENSO has been discussed in many other areas- I think the general impression has been of ENSO making a small contribution to the warming, but for instance the 2000s were warmer globally than the 1990s despite the mean phase of ENSO falling from positive to near-neutral, so probably not more than a small one.

Hi TWS,

Fair summation.

For those of us that subscribe to the PDO and other cycles impact on the global temperature scene, it is the secondary impacts on cloud formation that can have an added impact to the climate system (as this is the primary mechanism of altering albedo).

Of course I think its just plain common sense that cycles of warm and cold water appearing over such a vast surface is bound to have some direct impact due to heat transfer and distribution to the land.

Y.S

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Personally I very much doubt that the PDO has made a significant contribution to global warming in the last few decades, but at the same time, I think some of the arguments that are being used to dismiss the idea are flawed. ENSO has been discussed in many other areas- I think the general impression has been of ENSO making a small contribution to the warming, but for instance the 2000s were warmer globally than the 1990s despite the mean phase of ENSO falling from positive to near-neutral, so probably not more than a small one.

its not just the PDO but the whole system has been running on overdrive warm in the last decade or so. We've never seen such a long period where we've seen a combined +PDO/IDO/AAM and when you get that its not going to be any shocker to get temps rise...but note we've not been able to punch above a certain point and we've levelled off more or less now.

Also note how we came in about 0.1C below 1998's peak with a warmer Tropical Atlantic and a weaker El Nino, I'm sure if we had a 1998 El nino tihs year we'd peak pretty much at exactly the same point as we did in 1998.

As I've said countless times before look at early 2009 if you want to see what just 4-6 months can do to global temps when you do get two out of three of the big indices flip negative...we went from being about 0.35C above normal all the way down to something like 0.07C above normal when the La Nina combined for the first time since the late 80s with a cool AMO pattern and a weak -ve PDO signal...now if that could happen from a high baseline imagine what could happen when we get into a long term -PDO/AMO and any multi-year La Nina developed like we saw in the 70s...make no doubt about it we will go below average globally.

My BIG concern is more people become skeptical of AGW...then when we flip back into a +ve period again we see another big stair-step upwards in the space of 3-5 years of at least another 0.3-0.5C from where we are now, afterall its no surprise global temps first rose somewhat in the early 90s, then shot up during the late 90s and held firm when we've had the triple alliance as I like to call it.

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post-2752-055520700 1279613173_thumb.jpg

Show how 'clean' (not) our ships are! Borth Pacific yesterday from MODIS 'pic of the day'

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Everything is primed for a big global cooldown in the next 12 months, the La Nina is looking VERY impressive right now, and the PDO looks like its going to stay negative for some time. The Atlantic should also lose its tropical warmth as the hurricane season kicks in...so we effecvtivly have 3 oceanic factors all cooling at the same time...

Probably have a shot at going as cold as we saw in 1992-1994 with the global cooling that occured IMO, esp if the Nina really powers up...

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As the 'Hurricane season kicks in'?

No sign of that yet!!!

We've had a few seasons now with 'mid season downgrades' from NHC haven't we?

Why should that be?

Could it be the 'indicators' you feel 'predict' are 'old Hat'?

Could it be that we need revise the 'old thinking' as AGW re-writes the 'natural cyclical forcing's' book?

Time to think the un-thinkable K.W. .................

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Blimey GW, that's a big ask. Are you seriously proposing that a rise of less than 1degree C over the last 30 odd years can, or has over-ridden natural ocean cycles?

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As the 'Hurricane season kicks in'?

No sign of that yet!!!

We've had a few seasons now with 'mid season downgrades' from NHC haven't we?

Why should that be?

Possibly down to AGW theory claiming that frequency and strength of tropical storms will increase, which to me says there's something wrong with the theory atm.

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Fortunately, I've decided to buy a great big book on oceanography and will report back soon. I've also just this minute bought the normal selection of reviews on the subject to supplement the text (normal behaviour if you want to tell everyone the LI is good and everything else is not so good)

For those who wish to posit 'a few' then please refer back to Tamino's posts where 'a few' simply doesn't cut the mustard. Statistics is there for a a very (very!) good reason.

Report back soon :rofl:

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As for the hurricane season, well its probably more of a case...of dare I say it....the agencies not actually doing proper research on what could happen if the La Nina strengthens enough. In a mod/strong La Nina most seasons only get 12-14NS but they tend to feature quite a few beefy storms in those numbers. I've explained why in other places before but to put it simply the La Nina does not favour early development at all as we don't get the hybrid systems you get in neutral/El Nino years due to a more zonal flow.

So yeah its more of a case of the agencies under-estimating the La Nina in a big way, its REALLY becoming very impressive now in terms of the structure, probably has a reasonable shot at getting close to strong category if not into it and that will help to cool the globe I'd have thought over time.

Worth noting globally we are WAY down on the 2004-2006 period, I suspect the sun must be playing a role...

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