A system to derive tracks of barometric minima is presented. It isdeliberately using coarse input data in space (order of 2°×2°) and time (6-hourly to daily) as well as information from just onegeopotential level. It is argued that the results are, for one robust in thesense of an assumption of the IMILAST Project that the use of assimple as possible metrics should be strived for and for two tailored to theinput from reanalyses and GCMs. The methodology presented is a necessaryfirst step towards an automated storm track recognition scheme which will beemployed in a second paper to study the future development of atmosphericdynamics in a changing climate. The process towards obtaining storm tracks istwo-fold. In its first step cyclone centers are being identified. Theperformance of this step requires the existence of closed isolines, i.e., atopology in which a grid-point is surrounded by neighbours which all exhibithigher geopotential. The usage of this topology requirement as well as theconstraint of coarse data may lead, though, to limitations in identifyingcenters in geopotential fields with shallow gradients that may occur in thesummer months; moreover, some centers may potentially be missed in case of aconfiguration in which a small scale storm is located at the perimeter of adeep and very large low (a kind of "dent in a crater wall"). The second stepof the process strings the identified cyclone centers together in ameaningful way to form tracks. By way of several examples the capability toidentify known storm tracks is shown.
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