Balkanhawk is correct
The operator should provide the pilot with a table with Field Alt vs Temp= LW for several climb gradients in order to comply with approach climb performance.
In the airbus you only can find it until 2,5% for CAT I and 2,1% for CAT II/III.
FCOM 3.05.35
Any climb gradient greater than that , refer to the table that you should be provided.