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Troposphere height

Links , pictures, research, information.

troposphere rheemoclineatmosphere temperature layers with,height

In no specific order.

Theory. Height of the troposphere

http://www-das.uwyo.edu/~geerts/cwx/notes/chap01/tropo.html

extract

‘The height of the tropopause depends on the location, notably the latitude, as shown in the figure on the right (which shows annual mean conditions). It also depends on the season (1, 2). Thus, it is about 16 km high over Australia at year-end, and between 12 – 16 km at midyear, being lower at the higher latitudes. At latitudes above 60� , the tropopause is less than 9 -10 km above sea level; the lowest is less than 8 km high, above Antarctica and above Siberia and northern Canada in winter. The highest average tropopause is over the oceanic warm pool of the western equatorial Pacific, about 17.5 km high, and over Southeast Asia, during the summer monsoon, the tropopause occasionally peaks above 18 km. In other words, cold conditions lead to a lower tropopause, obviously because of less convection.

Deep convection (thunderstorms) in the Intertropical Convergence Zone, or over mid-latitude continents in summer, continuously push the tropopause upwards and as such deepen the troposphere. This is because thunderstorms mix the tropospheric air at a moist adiabatic lapse rate. In the upper troposphere, this lapse rate is essentially the same as the dry adiabatic rate of 10K/km. So a deepening by 1 km reduces the tropopause temperature by 10K. Therefore, in areas where (or at times when) the tropopause is exceptionally high, the tropopause temperature is also very low, sometimes below -80� C. Such low temperatures are not found anywhere else in the Earth’s atmosphere, at any level, except in the winter stratosphere over Antarctica.

On the other hand, colder regions have a lower tropopause, obviously because convective overturning is limited there, due to the negative radiation balance at the surface. In fact, convection is very rare in polar regions; most of the tropospheric mixing at middle and high latitudes is forced by frontal systems in which uplift is forced rather than spontaneous (convective). This explains the paradox that tropopause temperatures are lowest where the surface temperatures are highest.

The tropopause height does not gradually drop from low to high latitudes. Rather, it drops rapidly in the area of the subtropical and polar front jets (STJ and PFJ respectively in the Figure on the left), as shown in the Palmen-Newton model of the general circulation (Fig 12.16 or Fig on left). Especially when the jet is strong and the associated front at low levels intense, then the tropopause height drops suddenly across the jet stream. Sometimes the tropopause actually folds down to 500 hPa (5.5 km) and even lower, just behind a well-defined cold front. The subsided stratospheric air within such a tropopause fold (or in the less pronounced tropopause dip) is much warmer than the tropospheric air it replaces, at the same level, and this warm advection aloft (around 300 hPa) largely explains the movement of the frontal low (at the surface) into the cold airmass, a process called occlusion (Section 13.3) (4).

 

 

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Google search.. ‘pictures tropopause height’

https://www.google.com/search?q=picture+tropopause+height&tbm=isch&source=univ&client=firefox-b-d&sa=X&ved=2ahUKEwjlnsDf-bDjAhVDfX0KHcEUAu0QsAR6BAgEEAE&biw=1025&bih=491

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QBO research

QBO ( Quasi biennial oscillation)…
LIST OF PUBLISHED RESEARCH ARTICLES

(I will add to the list as l come across them)

Click on the title to load all further entries at the base of this page

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QBO time series

QBO time series
http://www.jisao.washington.edu/datasets/qbo/
“30 hpa zonal winds on the equator up in the stratosphere ( upper atmosphere layer)
A stratospheric wind band along the equatorial latitude .
Changes direction periodically. Either easterly or westerly direction zonally across the stratospheric equatorial line of latitude”
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Wikopedia

http://en.wikipedia.org/wiki/QBO

The QBO was discovered in the 1950s

by researchers at the UK Meteorological Office (Graystone 1959)”
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QBO period/frequency

http://web.atmos.ucla.edu/~cwhung/qbo.html

“Zonally symmetric easterly and westerly wind regimes alternate regularly with periods varying from about 24 to 30 months(Holton,1992)

.

The fastest observed oscillation had a period close to 20 months(1959-1961) and the slowest was 36 months(1984-1987),
while

the mean period was 28.2 months(Pawson et al 1993b);about 5 cycles in 12 years(Maruyama,1997)”.

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Can irregularities of solar proxies help understand quasi-biennial solar variations?

Nonlin. Processes Geophys., 21, 797-813, 2014
A. Shapoval1,3,4, J. L. Le Mouël2, M. Shnirman1,2, and V. Courtillot2
http://www.nonlin-processes-geophys.net/21/797/2014/
doi:10.5194/npg-21-797-2014
“We propose that the HSV( half schwabe) behavior of the irregularity index of ISSN Iinternational sunspot number)may be linked to the presence of strong QBO before 1915–1930, a transition and their disappearance around 1975, corresponding to a change in regime of solar activity.”

Discussed here
http://hockeyschtick.blogspot.co.uk/2014/07/new-paper-finds-another-potential-solar.html
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By weathercycles Posted in QBO
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QBO time series

QBO TIME SERIES DATA

QBO TIME SERIES

    DATA

30mb zonal wind at the equator, zonal averageCalculated at NOAA/ESRL PSD
For info http://www.esrl.noaa.gov/psd/data/climateindices/list/

LINK to time series data
Numerical values
http://www.esrl.noaa.gov/psd/data/correlation/qbo.data
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CURRENT STRATOSPHERIC TEMPERATURE

1 Hecta Pascal TEMPERATURE ANOMALY

    NORTHERN HEMISPHERE

NH  Temperature anomaly

    SOUTHERN HEMISPHERE

SH stratosphere temperature anomaly
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2012 / 2013 1 hPa STRATOSPHERIC TEMPERATURE ANOMALY

1 hPa stratospheric temperature anomaly 2012  2013

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global stratosphere temperature profile _ curent
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zonal stratosphere temps _ current
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By weathercycles Posted in QBO