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#895615 - 03/11/2010 23:11 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
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Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
In the post above, an extreme value I forgot to mention was the daily maximum temperature anomaly, plotted on the x-axis of all six graphs.
The Manilla mean daily maximum temperature anomaly in October 2010 was nearly three degrees below the average for the decade 1999 to 2008. shocked


Edited by Surly Bond (03/11/2010 23:17)
Edit Reason: word omitted
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#901622 - 28/11/2010 17:47 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
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Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Log of Smoothed Maximum Temperature and Rainfall
Last 3 years at Manilla

In Post #869352 of 24/6/10 I presented an earlier graph like this, showing Manilla's smoothed (gaussian, half-width 6 months) monthly temperature and rainfall anomalies. This one has complete smoothing to May 2010, with reduced smoothing for later months, until November 2010 is the raw anomaly (provisional to 28/11/10).


Recently, the rainfall anomaly curve has tracked the daily maximum temperature curve fairly closely, with each 12 mm of positive rainfall anomaly matching minus one degree of temperature anomaly. The last positive temperature anomaly peak in November 2009 was sharp, but the corresponding negative rainfall anomaly peak was broad.
Currently there is a large negative anomaly of maximum temperature and a large positive anomaly of rainfall. However, future smoothed values may not be quite so large.

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#902215 - 30/11/2010 16:00 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
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Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
As amendment to the above graph in Post #901622, final rainfall data make the November 2010 raw rainfall anomaly value +38.3 mm rather than +29.9 mm.
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#902913 - 01/12/2010 21:54 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
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Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Manilla Smoothed Monthly Anomalies of Climate Variables
Parametric Plots
Update for November 2010

I last discussed these trends in September (Post #880243).
In the current plots we see final smoothed trends for autumn 2010. These are plotted as filled red diamonds, the last being for May 2010. Unfilled diamonds mark provisional trends for winter 2010 and little-smoothed to unsmoothed points for spring 2010, ending with an orange diamond for the November 2010 raw value.

Daily Maximum Temperature
On each plot, the x-axis has the anomaly of mean daily maximum temperature. The min value in Feb 2008 (-1.61) and max value in Nov 2009 (+1.35) are also the extremes (plotted in blue) of the smoothed data set. In autumn 2010 (ending May-10) the smoothed temperature anomaly fell much faster than it had risen in the previous autumn. Partially smoothed later values suggest that an extreme negative temperature anomaly came in October 2010.

Rainfall
Rainfall anomalies are plotted (inverted) on the y-axis of the first graph. Fully-smoothed autumn values rose with falling maximum temperature, but remained negative. Later values generally rose rapidly to an extreme positive raw value of +38 mm in November.



Cloudiness
During autumn of 2010 the anomaly of percent cloudy days rose to a new record for fully-smoothed values. It continued to rise to an apparent extreme in October 2010.


Early morning Dew Point
The Dew Point anomaly was positive and rising in autumn. It seems to have peaked at less than a record value in September 2010.


Daily Temperature Range
The temperature range anomaly fell during autumn to a new negative record for smoothed data. It continued to fall to an apparent negative peak in September 2010.



Daily minimum temperature
Autumn daily minimum anomalies fell little below the peak of December 2009. Later they traced an arc through the "Equable" zone of the graph, ending near zero.



Subsoil temperature
The autumn subsoil temperature anomaly was near zero and scarcely falling. It then accelerated downwards to an apparent negative extreme in October 2010.
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#918527 - 30/12/2010 18:55 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
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Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW

This is a big climatic swing that we are having.


For over a year, there has been a persistent rapid decline in daily maximum temperature, matching a rapid rise in rainfall.
The swing seems to amount to about four degrees in temperature and 55 mm in monthly rainfall. If the peaks have already been reached, the swing will become rather less when the latest data have been smoothed.
Still, it will be much bigger than any other swing in this twelve-year record.

Most anomalies on this record are small: less than 20 mm per month for rainfall and one degree for temperature. Current anomalies are twice as large.
Other large anomalies are:
1. The 2002 extreme drought, with anomalies peaking in autumn at -26 mm for rainfall and +1.3 degrees for temperature;
2. Excessive rainfall (noticed by nobody) in spring 2005, peaking at +20 mm, with no temperature anomaly;
3. A very cool summer in 2007-08, with temperature anomaly -1.6 degrees, but no rainfall anomaly;
4. A heat-wave in spring 2009, with temperature anomaly +1.3 degrees, just as in the 2002 drought. This time, however, the rainfall anomaly was much less: only -15 mm.
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#919982 - 02/01/2011 20:08 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
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Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Manilla Smoothed Monthly Anomalies of Climate Variables
Parametric Plots
Update for December 2010: "Still More Flooding Rains".

New data for December 2010 allow updating with more smoothing applied to all months back to June 2010, which is now fully smoothed. A new commentary on the trends to replace the one in Post #902913 will be held over for another two months, when the winter months of 2010 will all be fully smoothed.

The December 2010 data, marked with orange diamonds, are yet again in the "Flooding Rains" area in the bottom left corner of five of the six graphs. Anomaly values of rainfall, cloudy days, Dew Point, temperature range and subsoil temperature are extreme. The Minimum temperature anomaly is stuck near zero.

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#956054 - 04/02/2011 20:38 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
Weatherzone Addict

Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Manilla Smoothed Monthly Anomalies of Climate Variables
Parametric Plots
Update for January 2011: "Flooding Rains" stop.

New data for January 2011 allow updating with more smoothing applied to all months back to July 2010, which is now fully smoothed. A new commentary on the trends to replace the one in Post #902913 will be held over for another month, when the winter months of 2010 will all be fully smoothed.

The January 2011 data, marked with orange diamonds, have leapt away from the "Flooding Rains" area in the bottom left corner of the graphs. Anomaly values of Maximum temperature and temperature range are up, and that of rainfall is down.
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#956070 - 04/02/2011 21:04 Re: Observations of climate variation [Re: Surly Bond]
crikey Offline
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Registered: 01/02/2011
Posts: 3184
Loc: Tweed Heads
Moisture from the seas north NW and NE of northern teritory are feeding moisture into the remnants of yasi. The system is gaining size. and looking to grow its tail is nearly connecting with the southern system in east SA and all of Vic Why is it starting to spiral. Is there such a thing as an inland cyclone or is that just a pretty pattern of spiralling cloud?. Refer to your satellite image on this page


Edited by crikey (04/02/2011 21:05)
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#969272 - 04/03/2011 20:42 Re: Observations of climate variation [Re: crikey]
Surly Bond Offline
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Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Manilla Smoothed Monthly Anomalies of Climate Variables
Parametric Plots
Update for February 2011

Sudden Rise in Temperatures!

I last discussed these trends in December (Post #902913).

In the current plots we see final smoothed trends for winter 2010. These are plotted as filled red diamonds, the last being for August 2010. Unfilled diamonds mark provisional trends for spring 2010 and little-smoothed points for summer 2010-11, ending with an orange diamond for the February 2010 raw value.

Daily Maximum Temperature
On each plot, the x-axis has the anomaly of mean daily maximum temperature. The min value in Feb 2008 (-1.61) and max value in Nov 2009 (+1.35) are also the extremes (plotted in blue) of the smoothed data set. In winter 2010 the smoothed temperature anomaly fell very rapidly to near the earlier record low smoothed value. Partially smoothed later values suggest that an extreme negative temperature anomaly came in November 2010. The raw value for February 2011 is remarkably high.

Rainfall
Rainfall anomalies are plotted (inverted) on the y-axis of the first graph. Fully-smoothed winter values were all positive, rising with falling maximum temperature. Later values generally rose rapidly to an apparent positive extreme in November.February's value was very low and January's was very high.


Cloudiness
During winter of 2010 the anomaly of percent cloudy days rose to yet a new record for fully-smoothed values. It continued to rise to an apparent extreme in October 2010, since when it has remained extremely high.


Early morning Dew Point
The Dew Point anomaly was positive and rapidly rising in winter. It seems to have peaked at less than a record value in October 2010. By February the anomaly was much less positive.


Daily Temperature Range
The temperature range anomaly fell during winter to yet a new negative record for smoothed data. It continued to fall to an apparent negative peak in October 2010. The raw value for February and the little-smoothed value for January are right back near normal.


Daily minimum temperature
Winter daily minimum anomalies remained little below the peak of December 2009. Later values traced an arc through the "Equable" zone of the graph, until February's raw value was again near the December 2009 peak ("Hot Days; Hot Nights").


Subsoil temperature
The winter subsoil temperature anomaly was below zero and falling quite rapidly. It then accelerated downwards to an apparent negative extreme in November 2010. By February, the raw value was back higher than any point on the 3-year trace.
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#982301 - 05/04/2011 18:52 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
Weatherzone Addict

Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Manilla Smoothed Monthly Anomalies of Climate Variables
Parametric Plots
Update for March 2011: Extreme cloudiness.

New data for March 2011 allow updating with more smoothing applied to all months back to September 2010, which is now fully smoothed. Smoothed September values include new 12-year record anomalies for daily maximum temperature (low), cloudy days (high) and daily temperature range (low).
Most of the March 2011 raw data values (orange diamonds) are nearer to normal than to recent extremes. As an exception, the March cloudiness anomaly is a record +37%: there were 19 cloudy mornings instead of 8.



A new commentary on the trends to replace the one in Post #969272 (above) will be held over until the spring months of 2010 are all fully smoothed.
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#987190 - 02/05/2011 21:25 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
Weatherzone Addict

Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Manilla Smoothed Monthly Anomalies of Climate Variables
Parametric Plots
Update for April 2011: Sunny return from "flooding rains".

New data for April 2011 allow updating with more smoothing applied to all months back to October 2010, which is now fully smoothed. Smoothed October values include new 12-year record anomalies for daily maximum temperature (low) and cloudy days (high).
Most of the April 2011 raw data values (orange diamonds), other than daily maximum temperature, are now on the "droughts" side of normal rather than the "flooding rains" side, which had dominated for about a year.



A new commentary on the trends to replace the one in Post #969272 (second above) will be held over until the spring months of 2010 are all fully smoothed.
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#992993 - 02/06/2011 13:24 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
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Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
"Flooding rains" climate peaked here in October 2010
Manilla Smoothed Monthly Anomalies of Climate Variables
Parametric Plots
Update for May 2011

Smoothed data to November 2010
Fully smoothed data for spring of 2010 show that several variables reached peak values during the season. First, temperature range anomaly reached a minimum in September. Next, in October, daily maximum temperature anomaly reached a minimum, rainfall anomaly a maximum, and Dew Point anomaly a maximum. In November, subsoil temperature anomaly reached a minimum. Cloudiness anomaly may have reached a maximum in that month, but perhaps smoothed December or January values will be higher.
Daily minimum temperature anomaly did not peak. Through spring it fell steadily from a high positive value.

In an earlier post I noted a tendency for variables to peak in a particular order.
"For a "flooding-rains" peak:
First: Daily Temperature Range (min);
One month later: Rainfall (max), Cloud (max);
Two months later: Daily Max Temperature (min), Dew Point (max);
Four months later: Daily Min Temperature (min), Subsoil Temperature (min)."

Not much is different in this case. In particular, daily temperature range was the first to peak (WHY?), and subsoil among the last. However, the time of rainfall maximum did not precede the time of daily maximum temperature minimum.



Data after November 2010
During summer most variables seemed to be moving towards "droughts" but this pattern broke down in autumn:
Max temp anomaly did not quite reach normal before falling again;
Rainfall anomaly became negative then returned to positive;
Cloud anomaly had just one negative value before returning to record cloudiness;
Dew Point anomalies accelerated to extremely low values;
Temp range anomaly went very positive before falling slightly;
Min temp anomaly fell rapidly, independent of max temp anomaly;
Subsoil temp anomaly stabilised at a slightly positive value.

I am surprised that extreme cloudiness and extreme low humidity occur together. I am also puzzled about the weak association between daily max and min temperatures. This is a worry because daily minimum temperatures provide the most consistent signal of climate change during the last century.

Note:
New data for May 2011 allow updating with more smoothing applied to all months back to November 2010, which is now fully smoothed. Fully smoothed data - gaussian smoothing with half-width 6 months - are plotted in red, partly smoothed data uncoloured, and unsmoothed data for the last data point in orange. January data points are marked by squares.
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#998244 - 30/06/2011 15:04 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
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Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
No droughts or floods here lately
Some parts of Australia have had floods or droughts lately. Rainfall records show it is NOT true for the north-west slopes of NSW. Perhaps there are other areas for which the same can be said.

To take long duration effects first, 30-year (360-month) rainfall totals have been neither extremely high (>90th percentile) nor extremely low (<20th percentile) since 1999-2000, when they were extremely high. They were similarly high in 1991 and 1984, and phenomenally high (>99th percentile) in 1978-79. The last time of extremely low rainfall of 30-year duration was 1954, more than half a century ago.
For ten-year (120-month) rainfall totals, the year 2010 had extremely low values due to lingering effects of the brief (in this area) drought of winter 2002. By 2011 this effect had passed. Going back, the next extreme values were high values in 1984, then phenomenally high values (as above) in 1978-79. Before 2010, the most recent extremely low 10-year rainfalls were in 1966-67.
For 12-month rainfall totals, extreme values come more frequently. There were extremely low values from November 2009 to June 2010, in January and February 2007, and (the 2002 drought) from July 2002 to April 2003. The latest extremely high 12-month values were August 1998 to April 1999: a high-rainfall event almost exactly compensating for the following low-rainfall event of 2002.

Rainfall events that are extremely high (leading to floods) or extremely low (droughts) lend themselves to hyperbole (now shortened to a buzzword). The weather really has been quite close to the average in recent years, at least here, providing nothing for demagogues to get their teeth into.
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#998823 - 03/07/2011 20:24 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
Weatherzone Addict

Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Dry air but not warm or sunny

Manilla Smoothed Monthly Anomalies of Climate Variables
Parametric Plots
Update for June 2011


Raw anomaly data for June 2011 (shown in orange) are a little strange.
Daily max temperature, shown on the x-axis of all six graphs, has stalled without quite rising to normal from the extreme cold of last October.
Two variables indicate severe drought: Rainfall was very low, and so was the early morning Dew Point.
Most other variables are near normal, or slightly to the "flooding rains" side of normal.
Percent of cloudy mornings (>4 Octas) remains stable at a very high positive anomaly. For a calendar month that had 35% cloudy mornings in the reference decade beginning in 1999, it now has 55% cloudy mornings. (Has this really happened nowhere else? Is Manilla uniquely affected?)

Note:
New data for June 2011 allow updating with more smoothing applied to all months back to December 2010, which is now fully smoothed. Fully smoothed data - gaussian smoothing with half-width 6 months - are plotted in red, partly smoothed data uncoloured, and unsmoothed data for the last data point in orange. January data points are marked by squares.
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#1003011 - 27/07/2011 23:33 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
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Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Peaks and troughs of temperature in the Quasi-Biennial Oscillation
Manilla, NSW data from 1999

Most of this data was graphed in an earlier post.
Fully-smoothed data (gaussian smoothing with half-width six months) now extends to January 2011, with partially-smoothed data for six months after that.

The graph shows anomalies relative to (1999-2008) monthly averages of daily maximum temperature. After smoothing, the pattern is a Quasi-Biennial Oscillation (QBO) with clear peaks and troughs, as marked. The amplitude of the oscillation was less than half a degree in 2005-6, but approached minus two degrees in October 2010. Daily maximum temperature has not returned to normal since that time
Counting only the marked peaks and troughs, the mean period of oscillation during 139 months was 18.5 months. The shortest period was 8 months (May-05 to Jan-06) and the longest 35 months (Dec-06 to Nov-09).
In this data set, certain seasons have more peaks and troughs than others:
Summer (DJF): 4/15;
Autumn (MAM): 3/15;
Winter (JJA): 1/15;
Spring (SON): 7/15.
Nearly half of the peaks or troughs occurred in spring. Whether or not spring is generally the preferred season for a peak or trough in the QBO, it is true that spring has been preferred lately.

My data is local. However, there must be some wider area where results would be similar. I suggest that this pattern may apply to the region "Rain1" in Fig. 2 of Drosdowsky and Chambers (1998).
Region "Rain1" is centred near Dubbo, NSW, (close to here) and is bounded by a line through Brisbane, Cunnamulla, Hillston and Bega.

These results must surely relate to discussions about the influence of Sea Surface Temperatures on Australian climate.

I am not qualified to comment, but I hope others may do so. To say that one peak or another matches an ENSO event will not do. The whole pattern needs to fit.
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#1003132 - 28/07/2011 18:43 Re: Observations of climate variation [Re: Surly Bond]
Surly Bond Offline
Weatherzone Addict

Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Peaks and troughs of rainfall in the Quasi-Biennial Oscillation
Manilla, NSW data from 1999

This graph shows rainfall anomalies rather than the daily maximum temperature anomalies in the post above. I thought I should present this because the research that defined the Australian climate region "Rain1" analysed rainfall, not temperature.
Anomaly values are relative to monthly means of the 125-year record.
As shown in various posts on this thread, peaks and troughs in smoothed rainfall anomaly tend to coincide with, or slightly lead those of maximum temperature taken in the opposite sense: high temperature with low rainfall. However, there are many mis-matches.

Analysis of this graph finds it very similar to the temperature graph:
Counting only the marked peaks and troughs, the mean period of oscillation during 139 months was 14.5 months. The shortest period was 7 months (Sep-07 to Apr-08) and the longest 29 months (Nov-00 to Apr-03).
In this data set, certain seasons have more peaks and troughs than others:
Summer (DJF): 2/19;
Autumn (MAM): 6/19;
Winter (JJA): 2/19;
Spring (SON): 9/19.
Again, nearly half of the peaks or troughs occurred in spring. Whether or not spring is generally the preferred season for a peak or trough in the rainfall QBO, it is true that spring has been preferred lately.
The raw rainfall anomaly value for July 2011 plots off the bottom of the graph. It will not be clear whether the current rainfall deficit is worse than that of 2002 for another six months at least.


As before, I invite anyone with detailed knowledge of the history of sea surface temperatures or the Southern Oscillation Index to comment on how this specific pattern of anomalies reflects that history.
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#1003216 - 29/07/2011 10:04 Re: Observations of climate variation [Re: Surly Bond]
Keith Offline
Meteorological Motor Mouth

Registered: 16/12/2001
Posts: 6453
Loc: Kings Langley, NSW
Surly, that link to Drosdowski in your penultimate post is most useful. I'm going to have a go at reproducing the process it describes, in relation to rainfall and the SSTs...although I've not yet worked out whether I can take it further and if so, how.

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#1003257 - 29/07/2011 13:18 Re: Observations of climate variation [Re: Keith]
ROM Offline
Meteorological Motor Mouth

Registered: 29/01/2007
Posts: 6628
SB, Climate4you has an extensive post including sat based graphs and etc on global cloud cover changes which might be of interest and relevance to you.

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#1003513 - 30/07/2011 19:08 Re: Observations of climate variation [Re: ROM]
Surly Bond Offline
Weatherzone Addict

Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Keith
I am glad the you may be able to build on the link to Drosdowsky and Saunders' 1998 paper.
I am just returning the favour, as you alerted me to Drosdowsky's 1993 papers. I made serious attempts to get more information about Drosdowsky's work or updates of it, but I failed. I infer that Australian government research on climate on seasonal time-scales ceased about the turn of the century.

ROM
Many thanks for that link to the "climate4you" web-site of Professor Ole Humlum (University of Oslo). That site is invaluable for comprehensive up-to date data on world climate.
I particularly appreciated his demonstration of the very poor fit of global warming and atmospheric carbon dioxide concentration.
Unfortunately, the cloud data set you linked ends in 2008, just when my cloudiness data goes ballistic. It does show that my base period is in a time of low global cloud cover, much lower than the 1980's. Perhaps we have returned to amounts of cloud cover that were normal then.
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#1003522 - 30/07/2011 19:55 Re: Observations of climate variation [Re: Surly Bond]
ROM Offline
Meteorological Motor Mouth

Registered: 29/01/2007
Posts: 6628
You're right SB. All the global cloud cover data seems to stop in 2008.
Bob Tisdale [ Climate Observations ] suggested KNMI Climate Explorer and I know that a lot of the techo climate bloggers are into KNMI for a lot of climate data but the cloud data stops in 2008.

Likewise with "The International Satellite Cloud Climatology Project (ISCCP) "
And the the online data. It just stops in 2008


Edited by ROM (30/07/2011 20:00)

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