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Post by acidohm on Mar 10, 2016 20:31:36 GMT
Thanks for putting all that together Mboy....really appreciated.
Bob Tisdale is very good at conveying these concepts.
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Post by graywolf on Mar 15, 2016 12:27:05 GMT
Febs PDO came in at another big positive ( 1.75) so on the way up again? In 8 months, should the positives remain, we will see more positive months since 98' than negative......... not a thrilling PDO-ve period to say the least!
With AGW forcing being noted in the PDO figures since the early 90's I have to wonder if this PDO-ve reflects what we ought to expect in future with only the extremes showing a negative PDO and the rest either neutral of positive/strong positive?
I suppose any measure using ocean temps as a guide will see issues once oceans show a warming trend?
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Post by sigurdur on Mar 15, 2016 12:41:44 GMT
Graywolf: When do you foresee the oceans showing a warming trend?
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Post by missouriboy on Mar 24, 2016 15:04:51 GMT
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Post by sigurdur on Mar 24, 2016 15:21:23 GMT
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Post by missouriboy on Mar 24, 2016 15:48:31 GMT
I was referring to the part east of Japan. Seems like the growing blue blob in the N Pacific may be deflecting the current southeastward toward about 30 N (rather than its usual 40 N) at about 180 E Longitude.
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Post by sigurdur on Mar 24, 2016 17:10:03 GMT
Ok, yep, the Oyashio Current.
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Post by icefisher on Mar 26, 2016 1:26:31 GMT
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Post by graywolf on Jun 8, 2016 15:12:23 GMT
Seem to have mislaid the thread! March came in at +2.0 followed by April with a big 2.62...... waiting on May now but the 'warm horse shoe persisted throughout the month ( as has June thus far?) so I'm expecting another big positive when the data is out?
So why is this period ( since 98') called negsative? when you look at the data there are more high positive values than negative high values ( 2.0 and over) since 98' and we are only 6 months off having the highest run of any sign since 98'? Is anyone expecting a return of the cold horse show prior to Christmas?
Anyhoo's, the oddest section of the data is the last section ( post 1980?) when we appear to see 'positive' or 'neutral' but no real real lengthy negatives?
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Post by acidohm on Jun 8, 2016 15:57:32 GMT
Seem to have mislaid the thread! March came in at +2.0 followed by April with a big 2.62...... waiting on May now but the 'warm horse shoe persisted throughout the month ( as has June thus far?) so I'm expecting another big positive when the data is out? So why is this period ( since 98') called negsative? when you look at the data there are more high positive values than negative high values ( 2.0 and over) since 98' and we are only 6 months off having the highest run of any sign since 98'? Is anyone expecting a return of the cold horse show prior to Christmas? Anyhoo's, the oddest section of the data is the last section ( post 1980?) when we appear to see 'positive' or 'neutral' but no real real lengthy negatives? This?? ioc-goos-oopc.org/state_of_the_ocean/all/
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Post by icefisher on Jun 9, 2016 4:32:32 GMT
Seem to have mislaid the thread! March came in at +2.0 followed by April with a big 2.62...... waiting on May now but the 'warm horse shoe persisted throughout the month ( as has June thus far?) so I'm expecting another big positive when the data is out? So why is this period ( since 98') called negsative? when you look at the data there are more high positive values than negative high values ( 2.0 and over) since 98' and we are only 6 months off having the highest run of any sign since 98'? Is anyone expecting a return of the cold horse show prior to Christmas? Anyhoo's, the oddest section of the data is the last section ( post 1980?) when we appear to see 'positive' or 'neutral' but no real real lengthy negatives? Why? Because its a "multi-decadal" effect. Since 1998 the index has overall been negative. Interestingly it has averaged positive for January thru May over the past 18 1/3rd years. But it has averaged negative for June through December. The effect is constantly changing over the 220months since Jan 98 the index has been positive 100 months and negative 120 months. But if you go back to 1976 the index has been positive 301 months out 484. So clearly on a multi-decadal scale its negative now. We will know if that changed in a decade or so. But if there was ever a place to not get sucked into wiggle watching this is it, especially since SST trends are removed to arrive at the index. Looking for a balance, assuming the index is balanced, we probably need another 118 months of negatives. If its not balanced then the index is actually inaccurate. . . .no doubt from being poorly defined area wise. But the PDO is relatively new and the ENSO index has changed area definitions about 3 times since it was created.
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Post by Ratty on Jun 9, 2016 5:01:45 GMT
[Snipped GW's post ] Why? Because its a "multi-decadal" effect. Since 1998 the index has overall been negative. Interestingly it has averaged positive for January thru May over the past 18 1/3rd years. But it has averaged negative for June through December. The effect is constantly changing over the 220months since Jan 98 the index has been positive 100 months and negative 120 months. But if you go back to 1976 the index has been positive 301 months out 484. So clearly on a multi-decadal scale its negative now. We will know if that changed in a decade or so. But if there was ever a place to not get sucked into wiggle watching this is it, especially since SST trends are removed to arrive at the index. Looking for a balance, assuming the index is balanced, we probably need another 118 months of negatives. If its not balanced then the index is actually inaccurate. . . .no doubt from being poorly defined area wise. But the PDO is relatively new and the ENSO index has changed area definitions about 3 times since it was created. Shifting the goalposts? IF, ** What do you mean by "especially since SST trends are removed to arrive at the index." ** ( Ice Fisher - IF saves keystrokes) .
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Post by icefisher on Jun 9, 2016 19:18:10 GMT
[Snipped GW's post ] Why? Because its a "multi-decadal" effect. Since 1998 the index has overall been negative. Interestingly it has averaged positive for January thru May over the past 18 1/3rd years. But it has averaged negative for June through December. The effect is constantly changing over the 220months since Jan 98 the index has been positive 100 months and negative 120 months. But if you go back to 1976 the index has been positive 301 months out 484. So clearly on a multi-decadal scale its negative now. We will know if that changed in a decade or so. But if there was ever a place to not get sucked into wiggle watching this is it, especially since SST trends are removed to arrive at the index. Looking for a balance, assuming the index is balanced, we probably need another 118 months of negatives. If its not balanced then the index is actually inaccurate. . . .no doubt from being poorly defined area wise. But the PDO is relatively new and the ENSO index has changed area definitions about 3 times since it was created. Shifting the goalposts? IF, ** What do you mean by "especially since SST trends are removed to arrive at the index." ** ( Ice Fisher - IF saves keystrokes) . from climatedataguide.ucar.edu/climate-data/pacific-decadal-oscillation-pdo-definition-and-indices"The Pacific Decadal Oscillation (PDO) is defined by the leading pattern (EOF) of sea surface temperature (SST) anomalies in the North Pacific basin (typically, polewards of 20°N). The SST anomalies are obtained by removing both the climatological annual cycle and the global-mean SST anomaly from the data at each gridpoint. Positive values of the PDO index correspond with negative SST anomalies in central and western North Pacific (extending eastwards from Japan), and positive SST anomalies in the eastern North Pacific (along the west coast of North America). The positive phase of the PDO is also associated with positive SST anomalies across the central and eastern tropical Pacific."
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Post by graywolf on Jun 13, 2016 14:12:51 GMT
Well May came in with a record high ( for the month) leaving just 5 more months of positive before it becomes the longest running contiguous signal since 98'........
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Post by icefisher on Jun 18, 2016 2:07:48 GMT
Well May came in with a record high ( for the month) leaving just 5 more months of positive before it becomes the longest running contiguous signal since 98'........ I wouldn't be surprised if it were a record at all. Its quite possible that the El Nino shift is much stronger when the Pacific is in its cold phase since much of the El Nino is attributed to warm water back sloshing into the eastern Pacific. If the cold phase of the Pacific causes more warm water in the western Pacific then that back slosh could be enhanced. This El Nino took me by surprise. While El Nino wise the numbers were not more powerful than 98 the push north of warm water out of the tropics was much larger than 98. It was very noticeable in waters off California and the effect on fish migrations was at least as strong as 1957 when a super El Nino occurred during the previous cold phase. No warm phase El Nino (from 1976 or 9 to 2010 or 12} had as much effect on pushing tropical migratory species into southern California as the 1957 and 2015 El Ninos. Unfortunately, the 1957 El Nino was not monitored. It was reconstructed. We really are infants in understanding our oceans. We know more about the surface of Mars than we do the bottom of the ocean.
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