To refine her research topic and information needs effectively, Amahle should focus on "climate change impacts on coastal cities in South Africa" and prioritise recent studies. This approach allows her to concentrate on a specific geographic area while ensuring that the information is relevant and up-to-date. By narrowing her focus, she can better manage the volume of information and gather insights that are directly applicable to her research questions.
The other options—considering all global coastal cities, restricting research to theoretical models, or reviewing literature from only one discipline—may either overwhelm her further or limit the scope and applicability of her findings.