ABSTRACT - DRUM - University of Maryland

above the convectively adjusted region, suggesting no direct role of convection on the
cold point temperature.
A variety of observational evidence, however, suggests the tropopause
temperatures are indeed affected by tropospheric processes [Johnson and Kriete, 1982;
Highwood and Hoskins, 1998; Sherwood et al., 2003]. A climatological connection
between tropopause temperatures and convection has also been shown [Reid and Gage,
1981; Reid and Gage, 1985; Randel et al., 2000]. Randel et al. [2000] showed that
variations in tropopause characteristics are coherent with the El Nino-Southern
Oscillation (ENSO). Kiladis et al. [2001] also showed the tropopause potential
temperature over a site in the western Pacific changes in response to the movement of
convection.
1.2.3 Overshooting deep convection into the TTL
One of the most efficient ways for deep convection to affect properties in the
TTL is by mixing-in of the overshooting deep convection into the air in the TTL. The
equivalent potential temperature in the boundary layer of convective regions peaks at
345 K and is generally less than ~355 – 360 K [Folkins et al., 2000]. ‘Overshooting’
deep convection describes convection reaching potential temperatures higher than
~355 – 360 K, and that has likely overshot its level of neutral buoyancy (LNB). If this
air subsequently mixes with higher potential temperature air during ‘overshooting’, the
resulting mixture will settle at altitudes above the parcel’s initial LNB.
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