Planned adaptation to climate change requires information about what is happening and why. While a long-term trend is for global warming, short-term periods of cooling can occur and have physical causes associated with natural variability. However, such natural variability means that energy is rearranged or changed within the climate system, and should be traceable. An assessment is given of our ability to track changes in reservoirs and flows of energy within the climate system. Arguments are given that developing the ability to do this is important, as it affects interpretations of global and especially regional climate change, and prospects for the future.