A ventilation apparatus for artificial ventilation of a patient, encompassing: - a respiratory gas source arrangement (15, 62) that furnishes an inspiratory respiratory gas for artificial ventilation of the patient; - a flow modification apparatus that is embodied to generate and to quantitatively modify an inspiratory respiratory gas flow; - a humidification apparatus that is embodied to quantitatively increase the absolute moisture content of the inspiratory respiratory gas flow, the humidification apparatus comprising for that purpose a liquid reservoir and a modifiable-power-level evaporation apparatus; - a respiratory gas conduit arrangement having a proximal longitudinal end located closer to the patient during operation and having a distal longitudinal end located farther from the patient during operation, in order to convey the inspiratory respiratory gas flow from the humidification apparatus to the patient; - a proximal temperature sensor that is embodied to detect the temperature of the respiratory gas flow in the proximal longitudinal end region of the respiratory gas conduit arrangement; - a humidity sensor arrangement that is embodied to detect at least one humidity state value of the inspiratory respiratory gas flow which indirectly or directly represents an absolute moisture content of the inspiratory respiratory gas flow; - a flow sensor that is embodied to quantitatively detect the respiratory gas flow; - a control apparatus which is signal-transferringly connected to the proximal temperature sensor, to the humidity sensor arrangement, and to the flow sensor, and which is embodied to control the operating power level of the evaporation apparatus depending on a predefined setpoint moisture content of the respiratory gas and depending on signals of the proximal temperature sensor, of the humidity sensor arrangement, and of the flow sensor, the humidity sensor arrangement being arranged upstream, in an inspiration direction of the respiratory gas flow, from the humidification apparatus and being embodied to detect the humidity state value upstream from the humidification apparatus; the ventilation apparatus comprising at least one ambient temperature sensor that is embodied to detect the temperature of the environment of the ventilation apparatus; the control apparatus being signal-transferringly connected to the at least one ambient temperature sensor and being embodied to control the operating power level of the evaporation apparatus, in addition to the dependences already recited, additionally depending on signals of the at least one ambient temperature sensor. - a respiratory gas source arrangement (15, 62) that furnishes an inspiratory respiratory gas for artificial ventilation of the patient; - a flow modification apparatus that is embodied to generate and to quantitatively modify an inspiratory respiratory gas flow; - a humidification apparatus that is embodied to quantitatively increase the absolute moisture content of the inspiratory respiratory gas flow, the humidification apparatus comprising for that purpose a liquid reservoir and a modifiable-power-level evaporation apparatus; - a respiratory gas conduit arrangement having a proximal longitudinal end located closer to the patient during operation and having a distal longitudinal end located farther from the patient during operation, in order to convey the inspiratory respiratory gas flow from the humidification apparatus to the patient; - a proximal temperature sensor that is embodied to detect the temperature of the respiratory gas flow in the proximal longitudinal end region of the respiratory gas conduit arrangement; - a humidity sensor arrangement that is embodied to detect at least one humidity state value of the inspiratory respiratory gas flow which indirectly or directly represents an absolute moisture content of the inspiratory respiratory gas flow; - a flow sensor that is embodied to quantitatively detect the respiratory gas flow; - a control apparatus which is signal-transferringly connected to the proximal temperature sensor, to the humidity sensor arrangement, and to the flow sensor, and which is embodied to control the operating power level of the evaporation apparatus depending on a predefined setpoint moisture content of the respiratory gas and depending on signals of the proximal temperature sensor, of the humidity sensor arrangement, and of the flow sensor,