Global mean temperature has already risen by more than 1ºC, and that also means that the impacts of climate change become more visible. Many natural and human systems are sensitive to weather conditions. Crop yields, river floods and associated damages, ecosystems such as coral reefs, or the extent of wildfires are affected by temperatures and precipitation changes. Other factors also come into play. So, for example, crop yields around the world have increased over the last decades because of increasing fertilizer input, improved management and varieties. How do we detect the effect of climate change itself on these systems, when the other factors are excluded? This question is central for impact attribution. 'Impact of climate change' is defined as the difference between the observed state of the system  and the state of the system assuming the same observed levels of non-climate-related drivers  but no climate change.
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report