Function to convert the radiation data. The conversion name can be understand as follow:
conversion_1 = MJ m-2 day-1 to J cm-2 day-1;
conversion_2 = MJ m-2 day-1 to cal cm-2 day-1;
conversion_3 = MJ m-2 day-1 to W m-2;
conversion_4 = MJ m-2 day-1 to mm day-1;
conversion_5 = cal cm-2 day-1 to MJ m-2 day-1;
conversion_6 = cal cm-2 day-1 to J cm-2 day-1;
conversion_7 = cal cm-2 day-1 to W m-2;
conversion_8 = cal cm-2 day-1 to mm day-1;
conversion_9 = W m-2 to MJ m-2 day-1;
conversion_10 = W m-2 to J cm-2 day-1;
conversion_11 = W m-2 to cal cm-2 day-1;
conversion_12 = W m-2 to mm day-1;
conversion_13 = mm day-1 to MJ m-2 day-1;
conversion_14 = mm day-1 to J cm-2 day-1;
conversion_15 = mm day-1 to cal cm-2 day-1;
conversion_16 = mm day-1 to W m-2.