Visualizing Science: How Color Determines What We See   [ Journal Article ]

Zeller, Stephanie; Rogers, David
2020, (Published in EOS: Science News by AGU).

Color plays a major role in the analysis and communication of scientific information. New tools are helping to improve how color can be applied more accurately and effectively to data.


Colormapping resources and strategies for organized intuitive environmental visualization   [ Journal Article ]

Samsel, Francesca; Wolfram, Phillip; Bares, Annie; Turton, Terece; Bujack, Roxana
Environmental Earth Sciences, 78 (9), pp. 269, 2019, ISSN: 1866-6280, (LA-UR-19-20060).

Visualizations benefit from the use of intuitive organized color application, enabling a clearer understanding and communication. In this paper, we apply the concept of semantic color association to the generation of thematic colormaps for the environmental sciences in combination with principals of artistic color theory to expand feature resolution and create visual hierarchies within a visualization. In particular, we provide sets of color scales, colormaps and color organization guidance for semantically aligned water, atmosphere, land, and vegetation visualization. Strategies for directing attention via saturation levels and saturation sets of colormaps enable deployment of these techniques. All are publicly available online and accompanied by tools and strategy guidance.


ColorMoves: Real-time Interactive Colormap Construction for Scientific Visualization   [ Journal Article ]

Samsel, Francesca; Klaassen, Sebastion; Rogers, David
2018, (LA-UR-17-29913).

The visualization of scientific data is both a science and an art, in which many tools are used to explore, discover and communicate the information within the data. This process is increasingly difficult, as the size and complexity of data is constantly advancing. Color is a potent tool in scientific data visualization, and has been well studied. However, color’s full potential for communication and discovery remains untapped. Effective use of color requires a depth of understanding and experience employing color and color relationships, in combination with tools to translate that knowledge into scientific visualization workflows. In this paper, we present ColorMoves, an interactive tool that promotes exploration of scientific data through artist-driven color methods in a unique and transformative way. We discuss the power of contrast in scientific visualization, the design of the ColorMoves tool, and the tool’s application in several science domains.

Art, Affect and Color: Creating Engaging Expressive Scientific Visualization   [ Inproceedings ]

Samsel, Francesca; Bartram, Lyn; Annie, Bares
In proceedings IEEE Visualization 2018, 2018.



Employing Color Theory to Visualize Volume-rendered Multivariate Ensembles of Asteroid Impact Simulations   [ Inproceedings ]

Samsel, Francesca; Patchett, John; Rogers, David; Tsai, Karen
Proceedings of the 2016 CHI Conference Extended Abstracts on Human Factors in Computing Systems, pp. 1126-1134, ACM, 2017, ISBN: 978-1-4503-4656-6, (LA-UR-17-20419).

We describe explorations and innovations developed to help scientists understand an ensemble of large scale simulations of asteroid impacts in the ocean. The simulations were run to help scientists determine the characteristics of asteroids that NASA should track, so that communities at risk from impact can be given advanced notice. Of relevance to the CHI community are 1) hands-on workflow issues specific to exploring ensembles of large scientific data, 2) innovations in exploring such data ensembles with color, and 3) examples of multidisciplinary collaboration.

Intuitive Colormaps for Environmental Visualization   [ Inproceedings ]

Samsel, Francesca; Turton, Terece; Wolfram, Phillip; Bujack, Roxana
Rink, Karsten; Middel, Ariane; Zeckzer, Dirk; Bujack, Roxana (Ed.): Workshop on Visualisation in Environmental Sciences (EnvirVis), The Eurographics Association, 2017, ISBN: 978-3-03868-040-6, (LA-UR-17-22224).

Visualizations benefit from the use of intuitive colors, enabling an observer to make use of more automatic, subconscious channels. In this paper, we apply the concept of intuitive color to the generation of thematic colormaps for the environmental sciences. In particular, we provide custom sets of colormaps for water, atmosphere, land, and vegetation. These have been integrated into the online tool: ColorMoves: The Environment to enable the environmental scientist to tailor them precisely to the data and tasks in a simple drag-and-drop workflow.

The Good, the Bad, and the Ugly: A Theoretical Framework for the Assessment of Continuous Colormaps   [ Inproceedings ]

Bujack, Roxana; Turton, Terece; Samsel, Francesca; Ware, Colin; Rogers, David; Ahrens, James
IEEE Visualization, 2017.

A myriad of design rules for what constitutes a “good” colormap can be found in the literature. Some common rules include order, uniformity, and high discriminative power. However, the meaning of many of these terms is often ambiguous or open to interpretation. At times, different authors may use the same term to describe different concepts or the same rule is described by varying nomenclature. These ambiguities stand in the way of collaborative work, the design of experiments to assess the characteristics of colormaps, and automated colormap generation.

In this paper, we review current and historical guidelines for colormap design. We propose a specified taxonomy and provide unambiguous mathematical definitions for the most common design rules.

A Crowdsourced Approach to Colormap Assessment   [ Inproceedings ]

Turton, Terece; Ware, Colin; Samsel, Francesca; Rogers, David
Lawonn, Kai; Smit, Noeska; Cunningham, Douglas (Ed.): EuroVis Workshop on Reproducibility, Verification, and Validation in Visualization (EuroRV3), The Eurographics Association, 2017, ISBN: 978-3-03868-041-3.

Despite continual research and discussion on the perceptual effects of color in scientific visualization, psychophysical testing is often limited. In-person lab studies can be expensive and time-consuming while results can be difficult to extrapolate from meticulously controlled laboratory conditions to the real world of the visualization user. We draw on lessons learned from the use of crowdsourced participant pools in the behavioral sciences and information visualization to apply a crowdsourced approach to a classic psychophysical experiment assessing the ability of a colormap to impart metric information. We use an online presentation analogous to the color key task from Ware’s 1988 paper, Color Sequences for Univariate Maps, testing colormaps similar to those in the original paper along with contemporary colormap standards and new alternatives in the scientific visualization domain. We explore the issue of potential contamination from color deficient participants and establish that perceptual color research can appropriately leverage a crowdsourced participant pool without significant CVD concerns. The updated version of the Ware color key task also provides a method to assess and compare colormaps.

Arctic Messages: Arctic research in the Vocabulary of Poets and Artists   [ Presentation ]

Samsel, Francesca

Arctic Messages is a multidisciplinary work designed to encourage dialogue on the changing Arctic ecosystems and ramifications on global societies. Driven by the desire to provide avenues into the science and impacts of the changing Arctic tundra, our team comprised of Arctic researcher, a poet, a visual artist and visualization experts set out to create a blended language able to speak to the general public. Arctic Messages is one facet of our broader effort - experimentation of communication mediums able to engage viewers and raise awareness of the Arctic and its impact on global weather patterns. The work centers on the belief that facts alone have not served us well in broadening interest and dialogue. We are seeking to craft a blended language that speaks to our humanity as well as our intellect.

ColorMoves: Optimizing Color's Potential for Exploration and Communication of Data   [ Presentation ]

Samsel, Francesca


Evaluating the Perceptual Uniformity of Color Sequences for Feature Discrimination   [ Inproceedings ]

Ware, Colin; Turton, Terece; Samsel, Francesca; Bujack, Roxana; Rogers, David
Lawonn, Kai; Smit, Noeska; Cunningham, Douglas (Ed.): EuroVis Workshop on Reproducibility, Verification, and Validation in Visualization (EuroRV3), The Eurographics Association, 2017, ISBN: 978-3-03868-041-3, (LA-UR-17-24206).

Probably the most common method for visualizing univariate data maps is through pseudocoloring and one of the most commonly cited requirements of a good colormap is that it be perceptually uniform. This means that differences between adjacent colors in the sequence be equally distinct. The practical value of uniformity is for features in the data to be equally distinctive no matter where they lie in the colormap, but there are reasons for thinking that uniformity in terms of feature detection may not be achieved by current methods which are based on the use of uniform color spaces. In this paper we provide a new method for directly evaluating colormaps in terms of their capacity for feature resolution. We apply the method in a study using Amazon Mechanical Turk to evaluate seven colormaps. Among other findings the results show that two new double ended sequences have the highest discriminative power and good uniformity. Ways in which the technique can be applied include the design of colormaps for uniformity, and a method for evaluating colormaps through feature discrimination curves for differently sized features.


Optimizing for Visual Cognition in High Performance Scientific Computing   [ Journal Article ]

Ware, Colin; Rogers, David; Petersen, Mark; Ahrens, James; Aygar, Erol
Electronic Imaging, 2016 (16), pp. 1–9, 2016, ISSN: 2470-1173.

High performance scientific computing is undergoing radical changes as we move to Exascale (1018 FLOPS) and as a consequence products for visualization must increasingly be generated in-situ as opposed to after a model run. This changes both the nature of the data products and the overall cognitive work flow. Currently, data is saved in the form of model dumps, but these are both extremely large and not ideal for visualization. Instead, we need methods for saving model data in ways that are both compact and optimized for visualization. For example, our results show that animated representations are more perceptually efficient than static views even for steady flows, so we need ways of compressing vector field data for animated visualization. Another example, motion parallax is essential to perceive structures in dark matter simulations, so we need ways of saving large particle systems optimized for perception. Turning to the cognitive work flow, when scientists and engineers allocate their time to high performance computer simulations their effort is distributed between pre and post run work. To better understand the tradeoffs we created an analytics game to model the optimization of high performance computer codes simulating ocean dynamics. Visualization is a key part of this process. The results from two analytics game experiments suggest that simple changes can have a large impact on overall cognitive efficiency. Our first experiment showed that study participants continued to look at images for much longer than optimal. A second experiment revealed a large reduction in cognitive efficiency as working memory demands increased. We conclude with recommendations for systems design.

Discovery Jam: An IEEE Vis 2017 Workshop Proposal   [ Inproceedings ]

Rogers, David; Aragon, Celia; Keefe, Dan; Meyer, Miriah; Samsel, Francesca
2016, (LA-UR-16-23006).

It is clear that modern scientific discovery requires a new data-intensive approach. Vast stores of data available - from experiments, observations and simulations - may enable countless new discoveries, yet scientists continue to struggle to make sense of their data. Like many IEEE VIS attendees, we believe visualization holds an answer to this problem, but we also believe that a new, perhaps even disruptive, approach is needed in order to realize this potential. Building on the success of our team’s halfday workshop at VisWeek 2016, we propose a full-day Discovery Jam workshop that includes a hands-on data hack-a-thon in collaboration with domain scientists. The Discovery Jam demonstrates - through example - a culture of collaboration and training a new cohort of scientists, technologists, and artists to work together toward discovery across disciplines. The Discovery Jam will bring scientists to VisWeek, to present their difficult, high-impact science discovery problems to experts in the vis community. The results from the workshop will be added to the online online community being hosted at

Visualization and Analysis of Threats from Asteroid Ocean Impacts   [ Inproceedings ]

Patchett, John; Samsel, Francesca; Tsai, Karen; Gisler, Galen; Rogers, David; Abram, Greg; Turton, Terece
2016, (Winner, Best Scientific Visualization and Data Analytics Showcase; LA-UR-16-26258).

An asteroid colliding with earth can have grave consequences. An impact in the ocean has complex effects as the kinetic energy of the asteroid is transferred to the water, potentially causing a tsunami or other distant effect. Scientists at Los Alamos National Laboratory are using the xRage simulation code on high performance computing (HPC) systems to understand the range of possible behaviors of an asteroid impacting the ocean. By running ensembles of large scale 3D simulations, scientists can study a set of potential factors for asteroid-generated tsunamis (AGTs) such as angle of impact, asteroid mass and air burst elevation. These studies help scientists understand the consequences of asteroid impacts such as water dispersement into the atmosphere, which can impact the global climate, or tsunami creation, which can place population centers at risk. The results of these simulations will support NASA’s Office of Planetary Defense in deciding how to best track near-Earth objects (NEOs).

Interactive Colormapping: Enabling Multiple Data Ranges, Detailed Views of Ocean Salinity   [ Inproceedings ]

Samsel, Francesca; Klassen, Sebastian; Petersen, Mark; Turton, Terece; Abram, Greg; Rogers, David; Ahrens, James
Proceedings of the 34rd Annual ACM Conference Extended Abstracts on Human Factors in Computing Systems, ACM, San Jose, California, 2016, (LA-UR-15-20105).

Ocean salinity is a critical component to understanding climate change. Salinity concentrations and temperature drive large ocean currents which in turn drive global weather patterns. Melting ice caps lower salinity at the poles while river deltas bring fresh water into the ocean worldwide. These processes slow ocean currents, changing weather patterns and producing extreme climate events which disproportionally affect those living in poverty. Analysis of salinity presents a unique visualization challenge. Important data are found in narrow data ranges, varying with global location. Changing values of salinity are important in understanding ocean currents, but are difficult to map to colors using traditional tools. Commonly used colormaps may not provide sufficient detail for this data. Current editing tools do not easily enable a scientist to explore the subtleties of salinity. We present a workflow, enabled by an interactive colormap tool that allows a scientist to interactively apply sophisticated colormaps to scalar data. The intuitive and immediate interaction of the scientist with the data is a critical contribution of this work.

Animated Versus Static Views of Steady Flow Patterns   [ Inproceedings ]

Ware, Colin; Bolan, Daniel; Miller, Ricky; Rogers, David; Ahrens, James
Proceedings of the ACM Symposium on Applied Perception, pp. 77–84, ACM, Anaheim, California, 2016, ISBN: 978-1-4503-4383-1.

Two experiments were conducted to test the hypothesis that animated representations of vector fields are more effective than common static representations even for steady flow. We compared four flow visualization methods: animated streamlets, animated orthogonal line segments (where short lines were elongated orthogonal to the flow direction but animated in the direction of flow), static equally spaced streamlines, and static arrow grids. The first experiment involved a pattern detection task in which the participant searched for an anomalous flow pattern in a field of similar patterns. The results showed that both the animation methods produced more accurate and faster responses. The second experiment involved mentally tracing an advection path from a central dot in the flow field and marking where the path would cross the boundary of a surrounding circle. For this task the animated streamlets resulted in better performance than the other methods, but the animated orthogonal particles resulted in the worst performance. We conclude with recommendations for the representation of steady flow patterns.


Pursuing Value in Art-Science Collaborations   [ Journal Article ]

Campbell, Bruce; Samsel, Francesca
35 , pp. 6-11, 2015.

Over decades and centuries, the practices of art and science have diverged as separate disciplines and, driven by scrutiny and opinions, have sought to define what makes a great artist or scientist. It is not surprising, therefore, that many scientists remain unfamiliar with the many and varied artistic contributions to scientific advancement. Art-science case studies aren't encountered in our everyday work, but they can be highly suggestive of approaches for creative thinking and innovation. Today you can readily find scientists whose work could be shared with the general public more effectively. By introducing an Art on Graphics department to CG&A, the department editors aim to expose the work of teams that draw on the skills of art, science, and technology professions to make rigorous innovative contributions to the domain of computer graphics and applications.

Using the Arts as a Bridge to Public Understanding of Data-Intensive Earth Science Research through Climate Prisms: The Arctic   [ Journal Article ]

Deck, Linda; Samsel, Francesca; Wilson, Cathy; Rodriguez-Acosta, Mireya

An ever-growing body of research in Informal Science Education is showing that the arts contribute greatly to engaging the free-choice science learner. This kind of learning goes on outside of the classroom, notably in science centers and museums, where novel, experiential approaches can be piloted. A new exhibit, Climate Prisms: The Arctic, is being mounted by a team of artists and scientists at the Bradbury Science Museum of Los Alamos National Laboratory. It presents the pipeline from collecting soil samples in the Arctic to analyzing them in the labs to the statistical analysis of the findings and on to the input into the climate model, using prisms of art: visual art, poetry, scientific text, information graphics, field imagery and others. The presentation encourages users to view Arctic science through these different lenses. Each person plots their own path, moving through the content at the pace and level that best enables them to engage with the material. With the entry points through multiple artistic voices, learners hearts and feelings are directly reached, building primarily affective connections and then curiosity, rather than cognitive. The project itself is a large display screen driven by a touch interface designed for individual or small group viewing. Content paths are determined by an underlying system of tags, levels, content categories and related research areas. A screen shows a set of images. Each image can be accessed to provide image-specific information or can be a launching pad for a new set of related content and images that allows the user to continue on their exploration journey. Each person, each time they visit, creates a unique path through over 2000 pieces of content according to the unique set of learning assets and interests they bring with them at that visit. Embedded assessment will log basic demographics and each individual foray through the content. These assessments will be analyzed to explore trends of use and drive further content development.

Visualization of ocean currents and eddies in a high-resolution global ocean-climate model   [ Inproceedings ]

Samsel, Francesca; Petersen, Mark; Abram, Greg; Turton, Terece; Rogers, David; Ahrens, James
Proceedings of the International Conference on High Performance Computing, Networking, Storage and Analysis 2015, 2015, (LA-UR-15-20105).

Climate change research relies on models to better understand and predict the complex, interdependent processes that affect the atmosphere, ocean, and land. These models are computationally intensive and produce terabytes to petabytes of data. Visualization and analysis is increasingly difficult, yet is critical to gain scientific insights from large simulations. The recently-developed Model for Prediction Across Scales-Ocean (MPAS-Ocean) is designed to investigate climate change at global high-resolution (5 to 10 km grid cells) on high performance computing platforms. In the accompanying video, we use state-of-the-art visualization techniques to explore the physical processes in the ocean relevant to climate change. These include heat transport, turbulence and eddies, weakening of the meridional overturning circulation, and interaction between a warming ocean and Antarctic ice shelves. The project exemplifies the benefits of tight collaboration among scientists, artists, computer scientists, and visualization specialists.

Climate Prisms: The Arctic Connecting Climate Research and Climate Modeling via the Language of Art   [ Journal Article ]

Samsel, Francesca; Deck, Linda; Campbell, Bruce

Climate science is conveyed via visualization of a climate model – an abstraction that removes the science from the research field activity that forms the basis for constructing the model. Climate Prisms: The Arctic is about bridging the distance between the physical world and the scientific visualization through multiple approachable modalities pulled from both the world of art and the world of science. By allowing participants to view science through different lenses, each person plots their own path, moving through the content at the pace and level that best enables them to engage with the material. The project itself is a museum-based exhibit featuring a large display screen driven by a touch interface designed for individual or small group viewing. Content paths are determined by an underlying system of tags, levels, content categories and related research areas. A screen shows a set of images. Each image can be accessed to provide image-specific information or can be a launching pad for a new set of related content and images that allows the user to continue on their exploration journey. Each person creates a unique path through hundreds of pieces of content. Embedded assessment will log basic demographics and each individual foray through the content. These assessments will be analyzed to explore trends of use and drive further content development.

Color Mapping in VIS: Perspectives on Optimal Solutions   [ Presentation ]

Samsel, Francesca



Art-Science-Collaborations: Examine the Spectrum   [ Inproceedings ]

Samsel, Francesca
VISAP IEEE Vis 2013, 2013.

Collaborations between artists, visualization specialists and scientists produce a broad range of outcomes. They vary widely in purpose, scope and form. Being familiar with the range of possibilities as well as understanding the vocabulary and processes of the respective disciplines facilitates the process. The collaboration process ranges from artists assisting with color maps and design decisions to scientists collaborating with artists on work designed to hang in a gallery. The outcomes often extend beyond the original intent. Visualization specialist and scientists speak of the surprising impacts on their work. Art and visualization both are exploratory processes as well as communication avenues. Collaborations between the three fields show the potential for outcomes from increasing understanding of science to discovering solutions to significant problems of our time.