Climate signals refer to the patterns or changes in the climate system that can be measured and used to understand long-term climate trends. These signals can include factors such as temperature, precipitation, wind patterns, and ocean currents, among others. By studying these signals, scientists can gain insight into how the Earth's climate is changing over time, and how human activities may be influencing these changes. Climate signals play a crucial role in climate research and can help inform decisions related to adaptation and mitigation strategies for addressing climate change.