One of the main scientific problems for understanding southern Africa’s climate is that different models give contradictory scenarios for climate trends over the next 5–40 years. Through a transdisciplinary learning approach and scientific research, ICLEI contributes to an improved understanding of climate processes, and regional and local climate trends that drive the southern African climate system’s natural variability and responses to change within that system. ICLEI addresses the challenge of providing accessible, timely, applicable and defensible climate information that is needed by decision-makers operating at the city regional scale.