When communicating climate visually, understanding how humans perceive information can be very valuable. What units do people naturally grasp, how do they judge quantity, and when do context effects distort perception? Drawing on vision science, Simon Rushton tries to provide answers to these questions, to help effectively convey quantities and relationships, and also understand when the eye is being misled. He explains the importance of choosing intuitive rather than abstract units, potential problems in conveying quantity, and strategies to minimize them. Furthermore, Rushton touches on recent research on whether visual summary statistics are useful and explain cases where visual representations deliberately exploit the working of the visual system to produce misperceptions.

Vision scientist and professor at the School of Psychology, Cardiff University