Database for CTM model validation studies
CTM model evaluation strategy
1. General concept
Model simulated tracer fields can be compared one-by-one with observed data included in the ETHmeg database. For each month between Jan 1995 and Dec 1998 a table can be obtained containing the times and positions of all observations availabe during that month. This information can then be used during a model run to interpolate at each model time step the simulated tracer fields to all measurement points available for that time. Thus for each observation point a corresponding set of interpolated model values is generated. The time and position table contains an additional column called ID which allows linking each observation point to the corresponding campaign and flight, and thus to the corresponding tracer measurements. For each campaign(and measurement platform) a specific range of ID numbersis reserved. IDs are numbered sequentially according to the flight number.
2. Step-by-step instructions
Note: the ETHmeg database focuses on the following tracers: O3, CO, OH, HO2, H2O2, H2O, NO, NO2, HNO3, and PAN. Partly other tracers were included as well.