The plot a month later

June 2, 2015 Leave a comment

Over the past month I have worked solid on rewriting the plot facilities

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Figure 1, low resolution web image, comparable as shown at the beginning of May except a different geographic projection, done using wildly different software.

This is a quick look at what is new, the full thing is about to be used as part of a major article at the Talkshop.

Why? I was thoroughly fed up with fighting gnuplot, drives many people half crazy trying to get it to do what is wanted, all too often it simply can’t. In this case the final straw was no way of disabling automatic smearing of colour, nor can it draw literal filled polygons. (very amusingly given the authors say it can’t it then when writing out SVG format proceeds to write out filled polygons… can’t make it up stuff)

I was already using GLE, a tool with ancient origins. This will do what I say so all those polygons are drawn one at a time. The whole thing is very complicated, more so since my code writes GLE code and data before passing the whole lot over for plotting (GLE in turn calls ghostscript with postscript code, wheels within wheels)

There is more…

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Categories: software, temperature

Images of the 1998 El Niño in world temperature maps

May 5, 2015 3 comments

A reader asked for a time representation… a tricky problem via a web site, the data is large…

Here are three different views, two from the UK Met Office and one from UAH, the newly released version. These run from January 1996 through December 2000.

Firstly here is an overview an Hovmoller plot for the same time span. These are widely used but rarely for earth whole views. Here are some I prepared earlier as a 2012 article (includes [2]) elsewhere which might help understanding on what I am doing for this article.Image

Figure 1, Hovmoller diagram of 1998 El Nino, UAH TLT V5.6 [1] (as PDF 142kB)

The 1998 El Niño event was similar to the less known ~1876 event, both seeming increasingly muted in the Met Office data. The El Niño form is a pulse of warmth primarily in tropical regions followed by a cool period. The warmth gradually disappearing apparently flowing poleward, producing a characteristic sideways V shape in Hovmoller graphics. The cool in inside the V. Perhaps preceeded by coolish. This pattern has repeated over the years.

Unfold

If instead of folding all longitudes into a mean as above a plain XY map for a month gives a different view, so we may be able to see from where on the globe there are contributions.

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Global temperature map comparison

May 4, 2015 7 comments
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UAH TLT V6 beta, click for larger

This new work showcases one month available for all datasets, February 2015. The image above, lower troposphere from UAH V6 beta is merely a picture, the true work is in a PDF for local display. The intent is information, not hitting you in the face, so whilst as such green is a colour few people like that is how it has turned out. New geographic map, new colours.

Combined images, PDF (2.9MB), the cover page explains more.

I leave the reader to draw conclusions. As I get accused, understating, some surprises are inside.

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A novel presentation of 177 UK meterorological sites

April 26, 2015 7 comments

This is a large work where I am dismayed at having a choice forced by inaction of others between junking the work or showing known defective data which precludes much in the way of worthwhile further analysis.

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Here is a 180 page document containing frequency plots for all 177 Met Office Datapoint site’s hourly data since July 2014. In addition geographic linkage is provided by location maps for each site and live links to public aerial images where known.

Document link, PDF 11.3MB

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Categories: analysis, weather

Annual report on GFS GCM performance

January 30, 2015 Leave a comment

A mailing list I receive from UCAR brought news of an addition to the GFS forecast archive “New Dataset: NCEP GFS 0.25 Degree Global Forecast Grids Historical Archive” and links to a web page.

On browsing an excellent general interest snippet appeared

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Page 16/17, performance over time for a few parameters of various GCM and with the observation on the GFS useful horizon “Increase is about one day per decade”.

Review of GFS Forecast Skills in 2013
Fanglin Yang
IMSG – Environmental Modeling Center
National Centers for Environmental Prediction

Link is on the performance review page, 2013 rev. is PDF (2.7MB)

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Categories: analysis, Modelling, weather

Fast tidal data facility, UNESCO / IOC

January 3, 2015 Leave a comment

A couple of days I spotted a data event worth following up but I needed high resolution tidal data, difficult to find.

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UNESCO / IOC have created a facility directly linked to many (768 listed) tidal gauges provided true high resolution data, such as 15 minute and with a record of up to 30 days.

The intent seems to be providing public data for safety and research, such as Tsunami monitoring.

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Categories: Datasets, sea level

Katesbridge exponential cooling

December 29, 2014 2 comments

The night of 28th to 29th December 2014 was calm under high pressure across much of the UK after a clear sunny winter’s day. It was going to be cold.

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[UPDATE: Met Office, -8.8C ]

This is a partial weather station in Northern Ireland, red trace is temperature, pink is dewpoint and green is wind. No other data.

This blog article is an addition to this one at Tallbloke’s, and providing the data.

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Categories: weather

History of early polar ice cores

December 12, 2014 Leave a comment

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From time to time the US military produce historical works.

Chester Langway[1] in retirement wrote this work to commemorate a 50th anniversary. Published by the US Army Corps of Engineers.

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Categories: History, Ice core

A real world demonstration of cloud controlling radiation

December 7, 2014 Leave a comment

The original text struck me as inappropriate so I’ve edited it. I put it down to being overtired. The original is archived if anyone wants to see it, just ask (there is a contact form), no questions asked on why.

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This is a huge plot including hourly data from WMO3768 Farnborough, England, a synoptic Met Office station where I estimate the site meets WMO 2010 recommendation Class 1, although the presence of a triangular airfield runway layout surrounding the station will have some side effects.

A details view of the plot is only practical via PDF (201kB)  Very likely the PDF will open looking as above so you need to set magnification and scroll around the plot, 100% is the intended view. Some details of interest are reproduced below at a normal scale.

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Categories: analysis, temperature, weather

Czech-Canadian tree ring study

September 26, 2014 1 comment

This post is in honour of a great mind where I have more to say sometime.

The late Vít Klemeš who died 2010 gave a talk on July 12, 2007, in the HW2003 Workshop on Analysis of Variability in Hydrological Data Series, at the IAHS General Assembly in Perugia, Italy.

He concluded with a truism I believe in

The moral of my talk is this: The most fun and perhaps the greatest value of doing something is in doing it. The results may well go up in smoke, be wrong, become obsolete and forgotten, but some new ideas may have emerged in pursuing them, and some of them may somewhere, sometime, bear fruit. …”

They have, right now.

And that is Vít Klemeš. He had a sense of fun, sense of humour, yet enough is revealed in past writing showing he comes across as quietly subtle, a real technician, the lack of ego which comes with confidence.

This presentation is as a PDF at a moderate technical level which might seem somewhat wooden in places. It needs a degree of background knowledge, without this maybe there is enough.

 

 

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Categories: humour, Minder
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