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Bushdodge
13th May 2021, 22:10
I've seen questions asking about "Warm Sector Depressions" in the new UK PPL Meteorology e-Exam. Does anyone have any suggestions as to where I can find reliable, factual information about "Warm Sector Depressions"?

I can't find this term used in the same way in the PPL books, my ATPL books or the ATPL books we have at work. I interpret "Warm Sector Depression" to be the WARM SECTOR of a FRONTAL DEPRESSION. Based on the 'correct' answers in the e-Exam, I can only conclude that they are using the term "Warm Sector Depression" to refer to the entire depression (and not just the warm sector).


https://cimg1.ibsrv.net/gimg/pprune.org-vbulletin/1536x1998/pprune1_7f07db43799f5960ebbea7bb0443c67852016bd9.jpg
https://cimg2.ibsrv.net/gimg/pprune.org-vbulletin/672x504/untitled_5e4177249632f4c9986407762d6f2c7bc7dc9929.png

excrab
14th May 2021, 09:31
Information about warm sector depressions can be found in the “Handbook of Aviation Meteorology” published in 1971 by her majesty’s stationary office. I have no idea if it’s actually reliable or factual, and I didn’t really understand it forty years ago either


https://cimg6.ibsrv.net/gimg/pprune.org-vbulletin/2000x1504/b782db0b_ef1a_4a79_9b68_be640735fc98_8dd8162f90043f0bc25f7c1 2139e83c45afe9566.jpeg

A small section of the million or so words of text states that “The depression itself, travelling with the fronts, usually has a velocity roughly equal in speed and direction to that of the geostrophic wind in the warm air”, which seems to be pretty much what it says in the extract in the original post.

Don’t know if that helps, but they obviously exist somewhere in the collective memory of the CAA question setters.

Alex Whittingham
14th May 2021, 10:21
I'd agree. there are other sorts of depressions, tropical cyclones for instance, polar lows. They are using the term 'warm sector depression' instead of 'frontal depression' I think.

selfin
14th May 2021, 17:58
A digital copy of the Handbook of Aviation Meteorology is available free of charge from the Met Office at https://digital.nmla.metoffice.gov.uk (Met Office General Met Publications -> Glossaries, Handbooks & Guides).

B2N2
14th May 2021, 20:16
Am I the only one who thinks this is ridiculous for Private Pilot level?

Whopity
14th May 2021, 22:13
I have a copy of Met.O.630/AP3340 Handbook of Aviation Meteorology 1960 which I was issued with in the RAF. It uses a sub-title "Warm-sector depression" under the broader heading General Distribution of Weather in a Frontal System.
For PPLs I rather like Brian Cosgrove's book; Pilot's Weather, a very pracical book aimed at Microlight Pilots. He makes no mention of a Warm Sector Depression but talks of Anabatic and Katabatic Fronts providing lots of pictures of the associated cloud formations..

As UK weather is predominately associated with frontal depressions, I think the associated weather is relevant to the private pilot.

MrAverage
15th May 2021, 09:38
I'm with you B2N2.

The average PPL here in the UK does 20 hours a year if he's lucky, possibly flying once a month, many do less. Certainly, I couldn't afford much more for the first ten years. I could also introduce you to many pilots who haven't picked up a book in decades, having only just scraped through their writtens. They probably didn't revise the areas they failed questions in either. The hope is that they remember the bits that really matter.

I would suggest it may have been better to show the candidate a picture of a squall line ahead of the aircraft and give four choices of what to do.

The sort of question the OP quoted is fine for RAF trainees and ATPL students, with their advanced capabilities, but not for a PPL student with possibly below average intelligence. Or as I call it, simply not that clever.

Whopity
15th May 2021, 11:44
We have no idea what the quesion was, the OP simply said I've seen questions asking about "Warm Sector Depressions"
By all accounts the new questions were set and vetted by a team of FIs with AOPA involvement. In the past questions were invariably set by Examiners whose background was in professional training and that often accounts for the unwarranted complexity of some quesions.
Without knowing what the actual question was, its difficult to say if it is relevant or not.

Fl1ingfrog
15th May 2021, 23:06
Regurgitated names: the illustration in the original post shows a depression's warm sector following it's development. Exactly the same thing but with the words in a different order than they were in the days of the empire. A 'warm sector depression' is also a 'depression warm sector'. Depressions are commonly formed in mid latitudes so giving to that name. The term 'Atlantic' was because, they were observed, most commonly, of being created there. Of course the same phenomenon happens throughout the world from a range of stimuli when differing air masses come together.

Anyway, I hope that old obsolete names aren't being re-used in the current exams there's enough concocted confusion already.

The sort of question the OP quoted is fine for RAF trainees and ATPL students, with their advanced capabilities, but not for a PPL student with possibly below average intelligence. Or as I call it, simply not that clever.

I presume that is tongue in cheek.

Bushdodge
19th May 2021, 11:48
Thanks everyone for the answers. I suppose the MetOffice handbook is a reasonable source for the CAA to use, even if the terminology may be outdated.

Unfortunately, that means that I will have to start teaching that warm sector depressions have circular isobars (which is a deciding factor in the 'correct' answer in the new exams). From all the information I can find, it would seem that the cold sector has circular isobars and the warm sector has straight, parallel isobars.

Fl1ingfrog
19th May 2021, 19:01
No, I wouldn't agree with that. An isobar is a line of equal pressure. It takes the shape of the pressure it depicts. The illustrations from the “Handbook of Aviation Meteorology” show lines that are not straight.

Bushdodge
19th May 2021, 20:31
The descriptions in the Bristol GS, CATS, and PadPilot ATPL books all either depict or state the warm sector isobars are straight, but a handbook written in the 70s and last updated in the 90s depicts something different. Really... who cares? We're pilots, not meteorologists. Before these questions appeared out of nowhere in the new and improved exams (at PPL level!), I had absolutely no interest whatsoever in what shape the isobars are... nor would any PPL holder find this information practical.

I suppose if I want a definitive answer as to what it is the CAA has decided I should already be aware of and be teaching, I'll have to ask them. The references to textbook pages in the old answer booklet were useful.

Whopity
20th May 2021, 08:52
The isobars in the cold sector will have a tight radius because they are close to the centre of the low wheras the isobars in the warm sector will have a much lower radius because they are a long way from the centre of high pressure and theoretically curve in the opposite direction. Sadly, this is beginning to look more like a pointless question.

Fl1ingfrog
20th May 2021, 12:14
Sadly, this is beginning to look more like a pointless question.

Yes I agree. The illustrations commonly used are over simplified and do sometimes infer that the warm air mass emanates from the centre of the depression and that depressions are circular and tight. This is not true. They vary in size and shape and the existence of cold/warm sectors are also complex in effect, shape and size. What is known is that warm air increases the density and so the pressure will therefore oppose the effects caused by the cold air mass. The distribution of pressure will be different in the warm air than that in the cold sector and cannot be depicted by straight or curved lines except as a simple illustration when a deeper knowledge is not required. You certainly cannot teach that the pressure distribution in the warm sector is always linnear because it rarely will be.

Fl1ingfrog
21st May 2021, 13:12
the feelings of hopelessness when encountering such a ridiculous question.

The only ridiculous question is the one that isn't asked. Thank you Bushdodge for asking the question, I'm sue that answering the question has been of benefit to us all.

Ascend Charlie
24th May 2021, 01:25
https://cimg8.ibsrv.net/gimg/pprune.org-vbulletin/894x1376/warm_sector_4af742c64858380db2b842ff5ba58bef828f0e0f.png
This looks more like a warm "sector" on a cold day...

excrab
24th May 2021, 09:17
https://cimg8.ibsrv.net/gimg/pprune.org-vbulletin/894x1376/warm_sector_4af742c64858380db2b842ff5ba58bef828f0e0f.png
This looks more like a warm "sector" on a cold day...

Isn’t that the same picture as in the original post, just turned through 90 degrees?

As the polar front runs generally SW to NE over the U.K. then for U.K. met theory the OP picture is theoretically more accurate, I would have thought. Using the word “theoretically”
as there is a lot of variation, as has been mentioned.

Ascend Charlie
25th May 2021, 10:39
Isn’t that the same picture as in the original post, just turned through 90 degrees?


Yes, to make it look like a warm tit on a cold day. Jeez doesn't anybody have a funny bone any more?