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Demonstration of fractional delay function on real data

November 13, 2013 1 comment
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Figure 1

The meteorological station at Armagh Observatory, Northern Ireland closed in 2000[1]. A lot of the data has been made online access via scanned logbooks and some digitised data, paid for primarily by lottery funds.

An unpublished version of the data is used as part of a fractional delay demonstration.

Earlier article providing a template and instructions is
https://daedalearth.wordpress.com/2013/11/12/fractional-dataset-delay-subsample-resolution-in-a-spreadsheet/

Read more…

Anders Angstrom: Nocturnal radiation at various altitudes

September 20, 2013 Leave a comment
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The curves bring out some interesting facts that deserve special consideration.
For ordinary values of the humidity, the effective radiation has a maximum at 1 to 4 km. altitude. An increase of the humidity or a decrease of the temperature
gradient shifts this maximum to higher altitudes. The effective radiation gradient
is consequently positive at low altitudes and negative at high altitudes. — A. Angstrom

Fig. 14 from paper 100 years ago by Anders Angstrom on LWIR emission. This shows families of curves grouped by two different lapse rates.

Note: This Daedal Earth blog article was rapidly produced to make the PDF available for citation elsewhere. Content may change later.

Sub-extract from Smithsonian Miscellaneous Collections, Volume 65, Number 3, published 1915. is A study of the Radiation of the Atmosphere

Physicist Dr Anders Angstrom was the son of physicist Dr Knut Anstrom (radiation instrument inventor) the son of physicist Dr Anders Angstrom after whom the wavelength unit the Angstrom is named. Confusion is understandable.

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High altitude atmospheric pressure and ozone, south pole

September 12, 2013 Leave a comment

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Overlay of south pole satellite measured Ozone and 1 hPa air pressure model. (note: 3 day difference of dates, data availability)

It’s spring in the southern hemisphere, sunlight is starting to buzz the atmosphere as the long night ends. Ozone is always low then.

Read more…

Categories: temperature, weather

JAXA/EORC: El Nino Watch

July 16, 2013 Leave a comment

 

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Although El Nino is not a particular interest of mine JAXA have a new web page which I think is good.

Click the image or follow this link.

The web server might be fairly slow responding if my experience from the UK is representative, no big deal. This might be because a lot of images are rendered and loaded before the page displays.

Read more…

Categories: Datasets, temperature

Is sea level really an issue?

Normalised sea level and temperature

This is likely to be controversial and dismissed by some as invalid, which is their problem.

The RSS data is monthly.

Topex/Jason data is sampled roughly every 10 days, processed into monthly and then normalised to the RSS data.

Both month data were low pass filtered at 10 years, with end correction. This is likely to be dismissed as impossible, look, it is self evidently about right.

All four are plotted above.

Other work has suggested there is a correlation between temperature and sea level, sea level lagging perhaps 4 years. (I doubt many people think that sea level causes temperature)

The actual sea level rises being talked about are extremely small relative to the size of the planet.

What if the top few x metres of sea water are warmed by 0.2K?

RSS dataset update v3.2 to v3.3

February 13, 2011 Leave a comment

So what is the difference?

Visually rendering shows a cleaner result, presumably a reduction in artefacts from the close to the knuckle high frequency response.

Not worked on time series.

Here we are for December 2010 (no old data version of Jan 2011)

December 2010 V3.2

December 2010 V3.3

Categories: analysis, Datasets, RSS, temperature

UAH global temperatures, version 5.4

January 28, 2011 Leave a comment

Earlier today I wanted to take a quick look at the global plots.

Invoke update here which gets new data, nothing happens. I’d forgotten, or it had not registered with me there is a version change and that means filename changes. No problem.

My only comment is wondering about the amount of month to month variation, an ongoing gripe with this kind of dataset (all global datasets suffer): annual variation should not be present. Such variation has the chickens in panic, watching every doom twitch is going to break eggs.

[Commented added 29th. Had a quick look at V5.4 post 2002 and it looks improved, less annual  variation. This problem is very tough for satellite data given a dataset from 1978 to date is a mix of disparate datasets. Only looking at post mid-2002 with UAH is single satellite, but as a whole dataset compromising one period for another is not an option, the dataset authors have a difficult job]

Here are September through December 2010 equal area plots, plus Hovmoller, 1990 through end 2010.

Click on an image for full size.

The pattern, can be seen over many years in Hadcrut3, is heat bumps in the tropics which then flows in time toward the poles, heat shedding. This is always followed by a colder time in the tropics. Pretty obviously this is in progress now. Expect much like the sequence after 1998. The recent cold in the northern temperature zone doesn’t figure, too transient and local to make the bigger picture.

I suspect a good measure of global is just a narrow band in the tropics, not global as such which adds confusion and time delays as heat flows. Those people trying to link terrestrial and solar might find it a better metric. That said, is there a variation in the degree of temperature variation in the north and of so why? Also the ongoing tilt from south to north, why? On the latter I suspect it is about to start moving back, but my reasons are unstated here.

Categories: analysis, Datasets, temperature, UAH

Arctic UAH TLT polar temperature plots

November 28, 2010 Leave a comment

Discussion on the Bishop’s blog could useful use plots of UAH lower troposphere data and since I can do this, two plots follow.

http://www.bishop-hill.net/blog/2010/11/27/the-arctic-gap.html

Both the following are rotated to roughly match the plots cited in the other blog.

Actually used, looks like 90,30 which is 30 degree clockwise, plot range +-4C, disc is for whole earth equal area:

lua query.lua uahtlt render year=2010 month=10 centre=90,30 size=1024,768 range=4 lamaz

Sept 2010

Sept 2010

Oct 2010

Oct 2010

This was all done quickly and I couldn’t remember how to do it! No doubt could be improved.

I am not looking for comments here.

Categories: sea ice, UAH

Most accurate global temperature?

November 6, 2010 Leave a comment

Further work on the satellite global monthly both RSS and UAH produces

global lower troposphere temperatureClick for full size.

This is the most accurate I can do at the moment.

A discovery was a time offset for the residual annual cycle and harmonics for both datasets, an unexpected and strange effect. Why? It ought to be centred on exactly one year.

I am nervous about allowing for this without knowing what is going on. Perhaps it is an artefact of the quantised satellite orbit mismatching orbital period. (is about 0.97 year instead of 1)

I’ve used datasets computed here from gridded because this avoids the Shannon limitation in the published data. (doubt it makes a material difference)

Data, intermediates, full explanations, ask.

Categories: analysis, Datasets, RSS, temperature, UAH

Time maps

April 1, 2010 2 comments

I am told the name for these is Hovmoller maps. Read more…

Categories: analysis, Datasets, temperature