The selections in this sub-menu allow the user to define the nature of the output from MAGICC. The Reference year for climate model output determines which year is assumed to be the baseline year relative to which future changes in global-mean temperature and sea level are calculated. The default year is 1990, as used by the IPCC. However, the user may wish to choose a year such as 1976 which is broadly representative of the period 1961-90, the thirty-year period used to define the baseline climatologies used in SCENGEN and in many other climate scenario and impacts assessments. Note that the choice of reference year in MAGICC will not affect the choice of reference year in SCENGEN.
The First year for climate model output determines the first year for which the range of diagnostic information from MAGICC is written to the report files that can be Viewed from the Main Menu. The default year again is 1990.
The Last year for climate model run informs MAGICC when to cease calculations and when to cease reporting. The default end-year is 2100, but the user may wish the calculations to continue to a later year if emissions information is given beyond 2100 (as in the stabilization emissions scenarios). If a date later than 2100 is selected, the user should be aware that the chosen Emissions Scenarios should also be appropriately amended to continue beyond 2100. Caution should be exercised when interpreting results from MAGICC beyond the year 2100.
The Printout interval for climate model determines the interval at which the diagnostic information from MAGICC is written to the report files that can be Viewed from the Main Menu. The default interval is five years, although there may be there are many occasions when intervals of, for example, one year or 10 years may be preferable.