Upper Wave - Typical Appearance In Vertical Cross Sections

by ZAMG

Isentropes:
Isentropes show mainly frontal character. No impact from Upper Wave
Temperature Advection:
Maximum at 300 hPa or at higher levels, connected to tropopause folding (related to potential vorticity), cold advection below the Wave bulge at lower levels
Vorticity Advection:
Significant maximum of positive vorticity advection at upper levels connected to the sharpening of the upper level trough at 300 hPa
Vertical motion:
Vertical motion indicates rising air, with the maximum at upper levels, due to a rising upper relative stream

	22 August 2005/12.00 UTC - Meteosat 8 IR 10.8 image; position of vertical cross section indicated

Temperature Advection

	22 August 2005/12.00 UTC - Vertical cross section; black: isentropes (ThetaE), red thin: temperature advection - CA, red thick: temperature advection - WA, orange thin: IR pixel values, orange thick: WV pixel values

Vorticity Advection

	22 August 2005/12.00 UTC - Vertical cross section; black: isentropes (ThetaE), green thin: vorticity advection - NVA, green thick: vorticity advection - PVA, orange thin: IR pixel values, orange thick: WV pixel values

Vertical Motion

	22 August 2005/12.00 UTC - Vertical cross section; black: isentropes (ThetaE), cyan: vertical motion (omega) - upward motion, orange thin: IR pixel values, orange thick: WV pixel values

Potential Vorticity

	22 August 2005/12.00 UTC - Vertical cross section; black: isentropes (ThetaE), dark green thin: potential vorticity <1 unit, dark green thick: potential vorticity >=1 unit, orange thin: IR pixel values, orange thick: WV pixel values

Distinction between Wave and Upper Wave according to vertical cross sections

Upper Wave	Wave
TA indicates a CF in CA, CA dominates	WA dominates at all levels in the area of cloud band
Intense PV sinking only down to 400 hPa, PV=0.8 units below 500 hPa, no significant PV at lower levels	PV = 1 down at middle and low levels, interaction with upper levels
Maximum of upward motion at higher levels	Strong upward motion throughout the low and mid levels of the troposphere

Below left is the case of an Upper Wave, below right is the case of a Wave (2nd row below left shows vertical cross section over Wave bulge). While the Upper Wave has no separate maximum of PV>=1 unit at low levels, the Wave case from the 4 July 2005/12.00 UTC shows a distinct maximum at low levels, which is usually more intense and can exceed PV>=2 units.

22 August 2005/12.00 UTC - Vertical cross section; black: isentropes (ThetaE), dark green thin: potential vorticity <1 unit, dark green thick: potential vorticity >=1 unit, orange thin: IR pixel values, orange thick: WV pixel values	04 July 2005/12.00 UTC - Vertical cross section; black: isentropes (ThetaE), dark green thin: potential vorticity <1 unit, dark green thick: potential vorticity >=1 unit, orange thin: IR pixel values, orange thick: WV pixel values


04 July 2005/12.00 UTC - Meteosat 8 IR 10.8 image; position of vertical cross section indicated

Menu Of Upper Wave

Key Parameters

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