Cartographic design and the quality of climate change maps

228 Climatic Change (2009) 95:219–230
surface temperatures 1970–2004.” For the only map published in an IPCC summary
report for policymakers, the evaluation reveals specific issues of cartographic quality
with this ‘high-visibility’ map. Our evaluation is of course subjective, and reflects: (1)
our choice of selected design principles, (2) the evaluation categories, (3) the lack of
multiple reviewers, and (4) the reviewers’ expertise in applying the design principles
to the evaluated map. Nevertheless, this kind of cartographic evaluation can provide
useful insights into the quality of climate change maps.
5 Toward a research and policy agenda for evaluating climate change maps
We have demonstrated how a climate change map can be evaluated. Other climate
change maps are likely to vary in quality and could benefit from such evaluation.
Poor quality climate change maps have implications for climate change research
and policymaking. We suggest a modest but important agenda to improve the
cartographic quality of climate change maps.
(a) Systematic evaluation of the cartographic design and quality of climate change
maps should be undertaken to assess and improve climate change maps.
Our evaluation was a preliminary demonstration. Evaluation methods should be
refined to include: (a) carefully designed sampling plans to select a population of
climate change maps to evaluate, (b) expanding the criteria (cartographic principles)
to apply in the evaluations, including possible weighting of criteria, (c) assembling
a panel of expert cartographers to assess map design using established evaluation
techniques, and (d) developing more elaborate and varied evaluation rankings. Such
evaluations could provide an important inventory of the state of climate change
map design, identify key examples of good design, educate climate scientists about
cartographic principles, and help target efforts to improve climate change maps.
(b) The impact of climate change maps on climate change research and policymaking
should be researched to better understand their specific role and influence.
Such research on the impact of climate change maps includes cartography of course,
but could usefully extend to psychology, sociology, and political science. There are
several key questions. How do maps influence or direct scientific efforts and research
priorities? What assumptions do scientists make about the audiences for whom they
produce the maps, do these assumptions need to change, and if so, how? How
effective are climate change maps for synthesizing and interpreting climate change
data for policymakers? How are specific maps being used to guide decision-making?
What are the implications of inserting inaccurate or misleading maps (purposefully
or not) into the policymaking process? What are the cumulative effects of maps
produced by scientific organizations when reprinted and propagated through the
popular media (unchanged or modified)? How can the cartographic design and
persuasiveness of climate change maps be improved? Research to address these
questions can illuminate the role of climate change maps, help identify key traits
of effective maps, and improve research, policy analysis, and public communication
related to climate change.