tag:blogger.com,1999:blog-2220966763638300672.post1607246704720216504..comments2023-07-29T05:11:23.558-04:00Comments on Climate Observations: February 2011 SST Anomaly UpdateBob Tisdalehttp://www.blogger.com/profile/15462377647970214137noreply@blogger.comBlogger7125tag:blogger.com,1999:blog-2220966763638300672.post-40428357725514494622011-03-16T05:52:17.938-04:002011-03-16T05:52:17.938-04:00Robert: I forgot to tell you. In the post I link...Robert: I forgot to tell you. In the post I linked for you the other day about calculating the AMO as the difference between the North Atlantic and the Rest of the World SST anomalies, I had used 15% as the scaling factor of the North Atlantic. The 15% was 1/2 of the 30% represented by the surface area of the Atlantic (North and South) when compared to the rest of the world WITHOUT the Arctic and Southern Oceans. That is, using the surface areas of the Atlantic, Indian and Pacific Oceans, the Atlantic represents about 30% of the global surface area. Half of that is obviously 15%. This seemed appropriate as a ballpark number since GISS deletes most of the Southern and Arctic Oceans. However, if you include the Southern and Arctic Oceans, the percentage of the North Atlantic would drop to around 12%. If you include only the surface area of the coordinates used in the post, that scaling factor for the North Atlantic would drop to around 11.5%.Bob Tisdalehttps://www.blogger.com/profile/15462377647970214137noreply@blogger.comtag:blogger.com,1999:blog-2220966763638300672.post-54069938262549595172011-03-14T19:51:48.160-04:002011-03-14T19:51:48.160-04:00Robert: I discussed the same method of calculating...Robert: I discussed the same method of calculating the AMO a few weeks before Zeke in this post:<br />http://bobtisdale.blogspot.com/2011/02/comments-on-taminos-amo-post_03.html<br /><br />The reason my graph... <br />http://i53.tinypic.com/2v1ukg5.jpg<br />...looks different than Zeke's is due to the differences in the SST datasets.<br /><br />I discussed that with Zeke on Zeke's AMO post at Lucia's.Bob Tisdalehttps://www.blogger.com/profile/15462377647970214137noreply@blogger.comtag:blogger.com,1999:blog-2220966763638300672.post-72518931555906717822011-03-14T16:29:20.193-04:002011-03-14T16:29:20.193-04:00Hey Bob,
I was wondering how would one compute an...Hey Bob, <br />I was wondering how would one compute an AMO index similar to how it was done over Lucia's (by Zeke) from a practical perspective using KNMI. I can make a gridbox for the North Atlantic just fine but how can I get a series for the rest of the world excluding the North Atlantic?Robertnoreply@blogger.comtag:blogger.com,1999:blog-2220966763638300672.post-2658928049466610512011-03-09T10:28:48.262-05:002011-03-09T10:28:48.262-05:00John: There are as many theories about the cause ...John: There are as many theories about the cause of the 1976/77 Pacific climate shift as there are papers. Each paper would offer an additional insight. Two that stand out are (1) a shift in sea level pressure in the North Pacific and (2) a pocket of extratropical warm waters from the below the surface of the South Pacific finding its way into the tropics. I haven't found one that is convincing on its own. 1976/77 was also the end of a multiyear La Nina. <br /><br />I have read a paper (maybe more than one) about shifts occurring in the 1910s and the 1940s as well, but it would take some time for me to find it (them) again.Bob Tisdalehttps://www.blogger.com/profile/15462377647970214137noreply@blogger.comtag:blogger.com,1999:blog-2220966763638300672.post-31436280942838495812011-03-09T09:35:24.454-05:002011-03-09T09:35:24.454-05:00Hi Bob -
Do we have any solid theories as to what...Hi Bob -<br /><br />Do we have any solid theories as to what caused the Pacific Climate Shift? Or any reason to think it will shift in the opposite direction (e.g. analysis showing past shifts occurred)?<br /><br />Trying to remember, but I can't recall anything specific.<br /><br />Thanks, as always.Johnnoreply@blogger.comtag:blogger.com,1999:blog-2220966763638300672.post-59479709571758433592011-03-09T06:22:40.522-05:002011-03-09T06:22:40.522-05:00I'm hoping the AMO will start to decline and/o...I'm hoping the AMO will start to decline and/or that there will be a Pacific Climate Shift in the opposite direction. That way it could be determined if the recent warming is simply an "alignment" of multidecadal ocean "cycles".Bob Tisdalehttps://www.blogger.com/profile/15462377647970214137noreply@blogger.comtag:blogger.com,1999:blog-2220966763638300672.post-3325950288158777502011-03-08T23:03:58.672-05:002011-03-08T23:03:58.672-05:00Thanks Bob,
So you're seeing another step up ...Thanks Bob,<br /><br />So you're seeing another step up in global SST? I think some AGW-theory critics were expecting (hoping for) a step down to appear by the end of this La Nina given that solar and many of the natural ossilations have changed direction recently. If it's not CO2, have you any ideas what might be making all the steps upward ones?HRnoreply@blogger.com