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Need better explanation and source

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"The air is compressed, and gets hotter" What like an Adiabatic process? Obviously this is not the right explanation because atmospheric pressure changes are far too small. Weburbia (talk) 05:02, 14 July 2021 (UTC)[reply]

No its not due to conservation of energy either. The heat is being carried in from the sea by the jet stream and is trapped in the heat dome, but need a proper reliable source to cover this. Weburbia (talk)

The problem is that all references up to now are the mainstream media, which is rather far from a student level in meteorology (not even talking about an expert level). The famous webpage from NOAA entitled "heat dome" relates this academic study: https://journals.ametsoc.org/view/journals/clim/31/14/jcli-d-17-0554.1.xml#bib37. They have in mind monthly-scale anomalies conducive to the rise of heat waves over the Texas area. The monthly scale is very complex and very very far from the laboratory experimental scale, so that any idea of "cooked up by the high pressure" would be just a child story. One important feature of a "heat dome" following NOAA's considerations is the feedback process from the soil which is consistent with a monthly scale and why it would not work for any ridge over a few days. A recurrent reference in the study is the 2010 Russian heatwave that has been studied at the monthly scale. The repeated "blocking" vocabulary ties to this monthly scale. Therefore, daily weather charts are not the best demonstration of any "heat dome" process. At least, we should see temperature time series over 30 days proving the rise of the heat waves.2A01:E0A:9D2:3E20:9240:6427:6F3E:B9E2 (talk) 16:45, 30 July 2021 (UTC)[reply]
As far as I can tell a heat dome is just a persistent anticyclone. It heats because air from above descends and is compressed because air pressure is higher at lower altitudes. This heats the air adiabatically. In addition anticyclones are cloud free so more sunlight reaches the ground and heats up the air. Anticyclones are regions of high air pressure but the pressure difference that heats the air is between high and low altitudes. The slightly higher pressure at low altitude causes the air to move outwards and draw air down from above which is heated. This is explained already on the anticyclone page. There may be a case for merging this page into there. Weburbia (talk) 17:53, 30 July 2021 (UTC)[reply]
I definitely agree with the description except the sentence about the outward motion. Outward motion and surface high pressure are the same thing (incompressibility rule), both are created by the descent, the descent is only the cause and not a consequence. But the scale and season of persistence is an important topic since Deng et al (the academic study) say: "The spring soil moisture anomalies subsequently play an important role in maintaining the drought and triggering the summer EHWs by a positive feedback associated with lower evaporation/precipitation" and, finally, "The dynamic mechanism proposed here could also apply to shorter time scales, such as the intraseasonal time scales" meaning that the process was first described at the seasonal scale, that is even larger than the monthly scale. I say it again, the reason why a "heat dome" webpage exists from NOAA is the study of Deng et al.2A01:E0A:9D2:3E20:9240:6427:6F3E:B9E2 (talk) 01:01, 31 July 2021 (UTC)[reply]
What about reading https://research.noaa.gov/article/ArtMID/587/ArticleID/2366/Ready-for-summer-heat-Study-finds-new-primary-driver-of-extreme-Texas-heat-waves? which is longer version of https://oceanservice.noaa.gov/facts/heat-dome.html2A01:E0A:9D2:3E20:C8CE:EA08:A1A7:2B7A (talk) 09:57, 31 July 2021 (UTC)[reply]
If you pay attention clearly to the words of the short version, NOAA say: "atmosphere traps hot ocean air". Why "ocean" ? Because this is the study of Deng et al: hot air rising from the western Pacific and descending over central (south) USA.2A01:E0A:9D2:3E20:F083:D19D:9325:F68 (talk) 10:05, 1 August 2021 (UTC)[reply]
This is a new article inspired by recent use of the terminology in the press during the extreme heat waves seen in North America. I think it is worth looking back to see how the term may have evolved. It had been used over at least the last decade in similar contexts. However, in scholar and book searches I find the term used more in the context of an "urban heat dome" which forms over a city rather than a much larger region. In an urban heat dome the heat can be generated from human activity (air conditioning, cars etc) or more likely from solar heat absorbed by buildings and roads where lack of vegetation and dry conditions prevent cooling by vaporisation. Atmospheric conditions can cause this heat to be trapped and build up. If this is the correct concept of a heat dome then is the recent phenomena an example of the same thing on a larger scale, or is it just a large and extreme anticyclone where different processes may be at work? I also see evidence that the term has been used previously for heating over dry equatorial regions such as the Sahara. Another question is whether the oceans play a role as suggested in some reports. The answers may be complex and I doubt I have enough expertise to answer it. Weburbia (talk) 11:37, 31 July 2021 (UTC)[reply]
I can understand that we are seeing a modern use but my point is that the NOAA's webpage was not a definition of this use but a vulgarization of a very specific process which concerns very specific scales, that is, the study of Deng et al. Let us consider an example: if a 1-week upper-level anticyclone stalls in summer at the subtropical latitudes over wet soils, would it be called a "heat dome"? For many mainstream meteorologists, yes (modern use), but looking at NOAA's and Washington Post descriptions, no because wet soils can damp out the heat process. I am sorry for the complexity of things, but if the "heat dome" word had originated from academic studies, it would have not been so complicated.2A01:E0A:9D2:3E20:F083:D19D:9325:F68 (talk) 10:49, 1 August 2021 (UTC)[reply]

Wiki Education assignment: WRIT 340 for Engineers - Spring 2024

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This article was the subject of a Wiki Education Foundation-supported course assignment, between 8 January 2024 and 26 April 2024. Further details are available on the course page. Student editor(s): Lorettaoei, Rabenbau, Kristenyscho, Maciej kilian (article contribs).

— Assignment last updated by 1namesake1 (talk) 23:16, 18 March 2024 (UTC)[reply]