The statement, "It is also 'more likely than not' that global average temperatures will temporarily exceed the 1.5°C threshold above pre-industrial levels 'for at least one of the five years'," indicates that there is a significant probability that global average temperatures will surpass the 1.5°C threshold above pre-industrial levels for a short period within a five-year time frame. In the context of climate change, the 1.5°C threshold refers to a target set by international agreements such as the Paris Agreement. The goal is to limit the increase in global average temperatures to no more than 1.5 degrees Celsius above pre-industrial levels to mitigate the most severe impacts of climate change. The statement suggests that there is a heightened likelihood that, due to ongoing climate change and greenhouse gas emissions, the world will experience a period where the global average temperature exceeds this 1.5°C threshold at least once during a five-year period. This underscores the urgency of addressing climate change and reducing emissions to mitigate its impact.