Slayt 1 - RTC, Regional Training Centre - Turkey

Impacts of Parameterizing Problems associated with using parameterizations can resultfrom Interactions between parameterization schemes, where eachscheme contains its own set of errors and assumptions (forexample, a soil model and radiation scheme passing back andforth information about heating the boundary layer) The increasing complexity and interconnectedness ofparameterizations, which result in forecast errors that are moredifficult to trace back to specific processes The largest impact of using parameterization schemes is usuallyon predictions of sensible weather at the surface. These problems and impacts make generic forecast rules-ofthumbless useful and require that forecasters apply physicalreasoning on a case-by-case basis when the processes beingparameterized are important to the forecast.