  We apply an approach from cognitive linguistics by mapping Conceptual
Metaphor Theory (CMT) to the visualization domain to address patterns of visual
conceptual metaphors that are often used in science infographics. Metaphors
play an essential part in visual communication and are frequently employed to
explain complex concepts. However, their use is often based on intuition,
rather than following a formal process. At present, we lack tools and language
for understanding and describing metaphor use in visualization to the extent
where taxonomy and grammar could guide the creation of visual components, e.g.,
infographics. Our classification of the visual conceptual mappings within
scientific representations is based on the breakdown of visual components in
existing scientific infographics. We demonstrate the development of this
mapping through a detailed analysis of data collected from four domains
(biomedicine, climate, space, and anthropology) that represent a diverse range
of visual conceptual metaphors used in the visual communication of science.
This work allows us to identify patterns of visual conceptual metaphor use
within the domains, resolve ambiguities about why specific conceptual metaphors
are used, and develop a better overall understanding of visual metaphor use in
scientific infographics. Our analysis shows that ontological and orientational
conceptual metaphors are the most widely applied to translate complex
scientific concepts. To support our findings we developed a visual exploratory
tool based on the collected database that places the individual infographics on
a spatio-temporal scale and illustrates the breakdown of visual conceptual
metaphors.
