Climate sensitivity in the Anthropocene refers to how much the Earth's temperature changes in response to factors like greenhouse gas emissions. Scientists suggest that the Earth's sensitivity to these changes is higher than previously thought, around 4-6 degrees Celsius for doubled CO2 levels. This higher sensitivity includes feedback from things like ice melting and changes in natural carbon sinks. However, accurately measuring this sensitivity is challenging due to limited historical data and gaps in current climate models. Understanding Earth's sensitivity to human-caused changes is crucial for setting effective greenhouse gas reduction targets.