You need it in order to cite your sources and give create to the creator of the source. You also need to know who the creator of the source is since you need to know if they are trustworthy or not. For example, an anonymous creator might give false info. And you also need to see if the person is bias or trusted.
In order for us to make sure of it, i.e. to make sure of the validity of the information because we cannot rely on any source without making sure of its source and the validity of the information and the existing data
Floods are made more likely by the more extreme weather patterns caused by long-term global climate change. Change in land cover—such as removal of vegetation—and climate change increase flood risk.
