Convection in PIDCAP - A descriptive approach
- Autor(en)
- Michael Hantel
- Abstrakt
Following the scientific objectives of BALTEX, this report contributes to a diagnostic understanding of higher latitude convection. For the PIDCAP period (Aug-Sep-Oct 1995) we have studied daily fields of: The subgridscale vertical flux c≡g-1cp ′ω′̄ of equivalent temperature, referred to as convective flux (diagnosed from routine gridscale data); analyzed surface precipitation; the convective available potential energy CAPE; lightning records; and radar patterns from the NORDRAD network. - We have suggested earlier that the convective flux is the proper dynamic measure to quantify convection. Here we show in a first case-study part that in areas with significant upward values of c the other parameters also indicate convective activity. Yet there is nowhere a one-to-one relationship between c and rain, or c and CAPE. In some cases the diagnosed convective fluxes are caused by gridscale frontal processes while in others they are due to static instability. - In a second statistical part we compare the first three EOF profiles of c with the subjectively classified convective flux types deep convection (DC) and boundary layer convection (BL). EOF1 is highly correlated with DC while the rotated EOF2+EOF3 is well correlated with BL. The classical convection indicators (CAPE, lightning) are weakly correlated among each other and with precipitation but hardly at all with the convective flux. - These results corroborate our earlier conclusion that the convective flux c is a useful diagnostic parameter. Nevertheless, understanding convection requires a concerted effort in which more than one tool is to be employed. © Gebrüder Borntraeger, Berlin, Stuttgart 2000.
- Organisation(en)
- Institut für Meteorologie und Geophysik
- Journal
- Meteorologische Zeitschrift
- Band
- 9
- Seiten
- 77-84
- Anzahl der Seiten
- 8
- ISSN
- 0941-2948
- Publikationsdatum
- 2000
- Peer-reviewed
- Ja
- ÖFOS 2012
- 1030 Physik, Astronomie
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/0a735e73-ce19-4f39-8653-c30eab0d2da0