A method of modulating the cooling of a gas turbine component (32, 34), comprising: determining a target component temperature (TComponent) at which the gas turbine component (32, 34) can be maintained without the gas turbine component (32, 34) experiencing a fatigue failure over the course of a desired life (Life) of the gas turbine component (32, 34); determining a cooling air temperature (TCool Corr) to achieve the target component temperature (TComponent) in the gas turbine component (32, 34) by interpolating between first and second data points formulated based on outputs (TCool Low, TCool High) from respective control maps (144, 146), wherein the outputs are determined based on the rotational speed of a member of a gas turbine comprising the gas turbine component, the temperature of the gas path at the inlet of a blade of the member, and an input value of a cooling air mass flow rate; determining a cooling air mass flow rate (WCool Corr) by interpolating between first and second data points formulated based on outputs (WCool Low, WCool High) from respective control maps (244, 246), wherein the outputs are determined based on the rotational speed of a member of a gas turbine comprising the gas turbine component, the temperature of the gas path at the inlet of a blade of the member, and an input value of a cooling air temperature; and determining: a demanded cooling air temperature by selecting the higher of the determined cooling air temperature and a minimum cooling air temperature; and a demanded cooling air mass flow rate by selecting the higher of the determined cooling air mass flow rate and a minimum cooling air mass flow rate; such that the fatigue failure does not occur over the desired life (Life) of the gas turbine component (32, 34). determining a target component temperature (TComponent) at which the gas turbine component (32, 34) can be maintained without the gas turbine component (32, 34) experiencing a fatigue failure over the course of a desired life (Life) of the gas turbine component (32, 34); determining a cooling air temperature (TCool Corr) to achieve the target component temperature (TComponent) in the gas turbine component (32, 34) by interpolating between first and second data points formulated based on outputs (TCool Low, TCool High) from respective control maps (144, 146), wherein the outputs are determined based on the rotational speed of a member of a gas turbine comprising the gas turbine component, the temperature of the gas path at the inlet of a blade of the member, and an input value of a cooling air mass flow rate; determining a cooling air mass flow rate (WCool Corr) by interpolating between first and second data points formulated based on outputs (WCool Low, WCool High) from respective control maps (244, 246), wherein the outputs are determined based on the rotational speed of a member of a gas turbine comprising the gas turbine component, the temperature of the gas path at the inlet of a blade of the member, and an input value of a cooling air temperature; and determining: a demanded cooling air temperature by selecting the higher of the determined cooling air temperature and a minimum cooling air temperature; and a demanded cooling air mass flow rate by selecting the higher of the determined cooling air mass flow rate and a minimum cooling air mass flow rate; a demanded cooling air temperature by selecting the higher of the determined cooling air temperature and a minimum cooling air temperature; and a demanded cooling air mass flow rate by selecting the higher of the determined cooling air mass flow rate and a minimum cooling air mass flow rate; such that the fatigue failure does not occur over the desired life (Life) of the gas turbine component (32, 34).