Ascension Decending

Ascension Island – Mid Atlantic

Well, here we have a drop in the middle of the Atlantic. But wait, there's more…

Notice that after dropping hard into the 1970’s, we get all of one year of data in the 1980’s? ( 1980 ) It is then followed by a 1991 and 1992 with all zero’s (one year could be a change of “Duplicate Number” with a reset of the running total, but 2?) then in 1993 we get October and November. So that “middle time” is very flaky with a lot of missing data. We “take a rise” back to zero (still down 1/3 C from the start and 1/2 C from the line the ‘tops’ tend to run along). So I don’t have a lot of faith in that last decade…

Maybe we can look at other Islands in the Atlantic to get a clue what’s really happening?

Sao Tome and Principe

Closer to the equator and up close to Africa. Perhaps a bit more land influenced during times of stong offshore winds, but on the edge of the Benguela Current that surrounds Ascension.

Sao Tome And Principe Monthly Anomalies and Running Total

Ok, 1/2 C rise to the trend line, but… It is dropping until we splice on another thermometer. Then it rises all the way back to the zero line, we drop one of the two thermometers, then drop the whole record in 1980. (There are records for 1982, 1989 and 1991, but the anomalies are “all zero” so these are not very useful…)

So it confirms the early drop, but then we have a “splice” issue to deal with.

Cape Verde Islands?

While it is a different body of water (North Atlantic) it is somewhat the same type of climate. Mid Atlantic Island near the Equator (within 15 degrees or so.)

Cape Verde Islands Monthly Anomalies and Running Total

Well, gee, that’s a rising trend. Isn’t it?

But what if we look more closely at the splicing and the data? There is one minor bit of “tuning” in this graph. Since a Running Total of Anomalies lags the event, I’ve lagged the graph by one year from the actual events. So when the thermometers change, the graph picks up in the following year when the anomalies from that “hit the graph”.

Cape Verde Islands by Segments Monthly Anomalies and Running Total

Harumph. So we’ve got a downtrend. We take a “flat” step up on dropping to a single thermometer. Then a final “rise in the end”. But what’s in that rise? A large quantity of missing data:

Year     dT  dT/yr Count (12 monthly anomalies Jan - Dec)
1982  -0.64      0  1     0    0    0    0    0    0    0    0    0    0    0    0	
1983  -0.64   0.18  1  -0.5 -0.1    0  0.3 -0.5  0.1    0    0  0.3  0.7  1.2  0.7	
1984  -0.46  -0.38  1  -0.5 -0.4 -1.3 -0.4  0.7 -0.4  0.7    0    0   -1   -1 -0.9	
1985  -0.83   0.01  1  -0.1  0.2 -0.5   -1 -1.6  0.5    0  0.6  0.4  0.7  0.2  0.7	
1986  -0.83  -0.29  1     0 -1.2 -0.5  0.1  0.5   -1 -0.9 -0.2  0.6    0 -0.4 -0.5	
1987  -1.12   0.44  1     0    0    0  2.4    0  1.6	0    0    0    0  1.3    0	
1988  -0.67   0.16  1     0    0  1.8 -1.7  1.4    0  0.8  0.2 -0.2 -0.4    0    0	
1989  -0.52   0.09  1   0.1    1    0    0    0    0    0    0    0    0    0    0	
1990  -0.42   0.1   1   0.1    0    0    0    0    0    0    0  0.5    0    0  0.6	
1991  -0.32  -0.03  1     0    0    0    0    0    0    0    0 -0.4    0    0    0	
1992  -0.36      0  1     0    0    0    0    0    0    0    0    0    0    0    0	
1993  -0.36  -0.05  1  -0.7    0    0 -0.1  0.2    0    0    0    0    0    0    0	
1994  -0.41  -0.05  1  -0.3    0    0    0 -0.2    0    0 -0.1    0    0    0    0	
1995  -0.46   0.18  1   1.3    0    0    0    0    0  0.9    0    0    0    0    0	
1996  -0.28   0.13  1     1    0    0    0    0    0    0 -1.6  0.2    0    0    2	
1997  -0.14   0.47  1     0    0  2.7  1.3  1.6    0    0    0    0    0    0    0	
1998   0.32   0.05  1     0    0  0.6    0    0    0    0    0    0    0    0    0	
2003   0.38  -0.1   1     0 -1.2    0    0    0    0    0    0    0    0    0    0	
2004   0.28  -0.14  1     0    0 -1.7    0    0    0    0    0    0    0    0    0	
2005   0.13  -0.13  1  -1.6    0    0    0    0    0    0    0    0    0    0    0	

Aside from the rampant number of “zero anomalies” (that usually mean missing data as opposed to the months being identical) notice that we have a gap from 1998 to 2003. So what are we really measuring (and splicing on) after 1986 ?

How About the South Atlantic

As we saw under the South American series, the Falkland Islands are a bit cool, but South Georgia show a bit of rise at the end:

Falkland Islands

Falkland Islands Hair Graph monthly anomalies and cumulative

but it, too, cuts off in the early 1980s.

South Georgia

South Georgia Hair Graph monthly anomalies with cumulative

Where we have a long down trend that suddenly reverses at the end. But wait a moment… that end. It jumps from 1982 to 2006… What are we really measuring THERE?

Year     dT  dT/yr Count (12 monthly anomalies Jan - Dec)
1981  -0.98   0.86  1   0.6  1.5 -0.5  0.4 -0.4 -0.7    3  3.7  1.5   -2  1.9  1.3	
1982  -0.12   0.03  1   1.2 -0.8    0    0    0    0    0    0    0    0    0    0	
2006  -0.08  -0.14  1     0    0    0    0    0    0    0    0    0    0 -1.7    0	
2007  -0.23  -0.99  1  -1.7 -1.4    0    0 -2.2 -0.5 -3.1  0.2 -0.9  0.9 -1.9 -1.3	
2008  -1.22    0.6  1     0    0    0    0    0    0    0    0    1  1.4  4.8    0	
2009  -0.62   0.86  1   2.4  0.9  2.6 -1.9  1.9  1.1  3.5 -2.4  0.6    0    0  1.6	
2010   0.24  -0.24  1  -2.9    0    0    0    0    0    0    0    0    0    0    0	

A lot of holes and missing data…

Conclusions

So there is the giant part of the globe, the Atlantic, that’s got nicely positioned islands suited to measuring the temperature. That are showing a very interesting cooling trend. And they substantially are cut off mid-stream.

Now, decades later in some cases, we “take a splice” and start recording anomalies again. And we’ve seen that spices are bad things…

Where there is some “warming” it is strongly tied to instrument changes and happens as something of a “step function” with those changes.

There are global scale oscillations where one part warms and another cools by a degree or so at a time. With no idea what really happened in the Atlantic (and especially the larger South Atlantic) since the 1980’s we have no clue if it continued to cool as “warming” was found in another quarter of the globe.

IMHO, it is Very Important to get vetted and validated records for those islands, from ORIGINAL RAW sources (not “corrected” nor “adjusted”) to fill in this part of the data set. With little idea what’s happening in at least 1/4 of the world, we can have no assurance that “elsewhere” means anything other than one side of an offsetting oscillator. Worse, it looks like we’ve begun to add those islands back in, now that the major ocean currents have swapped again. (We may be selecting specific phases of that oscillation and not realize it. Double booking “trends” that are just “half cycles”. )

The World Ocean seen from above the south pole

Original Image

Pick up a globe and look at it from the bottom. Notice that large empty place between South America, New Zealand and French Polynesia? Notice that “big empty” in the South Indian Ocean? Punctuated by Prince Edward Island, Crozet Island and Kerguelen Island. Where are THEIR data in the GHCN? If you know nothing about 1/3 of the planet, what do you know?

Ships at Sea Monthly Anomalies and Running Total

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