With discussions on what collective action must be taken to decrease fossil fuel emissions that lead to warming and extreme weather events happening on the world stage, the Purdue Climate Change Research Center (PCCRC) released animations to illustrate what is happening in Indiana.
Andrea Nebhut, a graduate student in the Purdue Forestry and Natural Resources department under Dr. Jeff Dukes, director of the PCCRC, studies the intersection of climate change, plant invasion and ecosystem services. She explained her motivation for creating the animations.
“Carbon dioxide and other gases that cause climate change are invisible, and so their impact on climate change is something we can’t see as they’re happening,” Nebhut said. “With these animations, I hope to communicate the causes and consequences of climate change on a scale that feels personal and actionable to Indiana residents.”
Animations
Background
Anthropogenic greenhouse gas emissions are changing the Earth’s climate. If current rates of greenhouse gas emissions continue, Indiana will be 5-6°F warmer by mid-century, with detrimental consequences for the local environment, human health, and the economy (Widhalm et al. 2018). However, while 75% of Indiana residents agree that climate change is occurring, fewer than 40% regard it as resulting entirely or mostly from human activities, and only 15% believe that it will have substantial impacts on their own lives (Houser et al. 2021). These inaccurate beliefs result in limited adoption of either personal or local policy and infrastructural strategies to limit greenhouse gas emissions, such as switching to energy-efficient light bulbs or shutting down local coal-fired power plants before the end of their operational lifetime. To address these misconceptions and ultimately mitigate the impacts of climate change, climate scientists must effectively communicate the causes and consequences of climate change to the public on a scale that feels personal and actionable.
Short animations are one communication tool to effectively share climate research with the public because they are easily understood by a non-scientific audience, are visually attractive and attention-grabbing, and can be shared across popular social media platforms to a wide and diverse audience. Furthermore, by focusing on the physical scale of Indiana’s carbon emissions and the impact of climate change on Indiana’s corn production, it is possible to make the invisible problem of greenhouse gas emissions and its resulting abstract problem of climate change tangible, immediate, and relevant to Hoosiers.
With these goals in mind, Nebhut produced three short animations depicting 1) the quantity of carbon dioxide released from fossil fuel combustion in Indiana across time scales ranging from hours to decades, 2) the quantity of carbon dioxide emitted from fossil fuel combustion by each of Indiana’s economic sectors, and 3) the decline in mid-century corn production under an intermediate emissions scenario compared to the state’s yield potential.
In 2018, Indiana emitted 192.43 million metric tons of carbon dioxide from fossil fuel combustion, making it the 8th largest carbon emitter in the United States despite being ranked only 17th in population (EPA 2019; USCB 2021). Approximately 45% of Indiana’s carbon dioxide emissions from fossil fuel combustion originated in the electric sector, which remains dominated by carbon-emitting coal and natural gas, though solar and wind energy capacity has grown substantially (EIA 2021; Nderitu et al. 2017). The industrial sector, which includes manufacturing, agriculture, mining, and construction, accounts for 25.09% of Indiana’s carbon emissions, and the transportation sector, which includes automobiles, trains, aircraft, and ships, accounts for 21.96%. Finally, Indiana’s residential and commercial sectors, which include private households, businesses, governments, religious and social groups, and sewage treatment plants, account for just 4.64% and 3.09% of the state’s carbon dioxide emissions, respectively.
Each of these sectors will be vulnerable to climate change (Widhalm et al. 2018), but possibly none more so than the industrial sector due to its inclusion of agriculture, which is inherently tied to precipitation and temperature as determinants of plant and livestock production. In 2020, Indiana was the 9th largest agricultural producer in America (USDA 2021a) and generated $4.4 billion from the production of 981 million bushels of corn (USDA 2021b). However, increasing temperatures and changing precipitation patterns threaten to diminish yields relative to their potential. Already, warming night temperatures are leading to dwindling corn yields and by mid-century, statewide decline in corn yields may reach 12% in an intermediate emissions scenario, with regional declines spanning 7 to 14% (Bowling et al. 2020).
Methods
CO2 Emissions Across Timescales
To convey the physical scale of Indiana’s carbon emissions over time, Nebhut depicted Indiana’s total hourly, daily, weekly, monthly, yearly, and decadal carbon dioxide emissions from fossil fuel combustion as a growing, to-scale sphere hovering over downtown Indianapolis. The size of the sphere is based on carbon dioxide emissions data from the USEPA’s Inventory of U.S. Greenhouse Gas Emissions and Sinks 1990-2018 (EPA 2019). She used the sum of Indiana’s sector emissions from 2018 as representative of the state’s annual emissions, then divided this sum by the relevant time length to estimate Indiana’s average hourly, daily, weekly, and monthly emissions. For the decadal emissions, Nebhut summed all carbon emissions across all sectors from 2009 to 2018. She then converted these estimates of Indiana’s carbon dioxide emissions from fossil fuel combustion from millions of metric tons to a volume with the ideal gas law, assuming an air pressure of 1 atm and a temperature of 294.3°K (70.1°F), then calculated the radius of a sphere with these volume estimates.
CO2 Emissions by Sector
To explain the sources of Indiana’s carbon emissions from fossil fuel combustion, Nebhut split Indiana’s total 2018 carbon dioxide emissions into sector-specific bubbles based on estimates of per-sector emissions data from the USEPA’s Inventory of U.S. Greenhouse Gas Emissions and Sinks 1990-2018 (EPA 2020). She then calculated the size of these quantities of carbon dioxide as described above, then depicted each as a sphere hovering over downtown Indianapolis.
Mid Century Corn Yields
Finally, to communicate the potential effects of climate change on Indiana’s agricultural production, Nebhut visualized declining mid-century corn yields under an intermediate-emissions climate scenario as a shrinking pile of corn in downtown Indianapolis. To produce this animation, she acquired mid-century, intermediate-emissions corn yield data from Bowling et al. 2020, who used projections of technological improvements alongside models of Indiana’s future climate, crop growth, and hydrology to estimate corn yields under medium and high greenhouse-gas emissions scenarios relative to their potential without climate change. They found that under a medium-emissions scenario, regional corn yields would decline by 7 to 14% by mid-century relative to yield potential in an unchanged climate. By combining these regional projections of tons of corn produced per hectare and reports on the number of acres of corn grown in each of Indiana’s counties from the USDA’s 2017 Census of Agriculture (USDA 2019), Nebhut estimated how many tons of corn would be produced in each region, then Indiana as a whole, under each climate change scenario in Bowling et al. 2020. By these calculations, Indiana would produce approximately 27,750,000 tons of corn by 2044-2073 in an intermediate-emissions scenario compared to the yield potential of 31,520,000 tons of corn in a scenario without climate change, which marks a 12.0% reduction in mid-century corn production compared to yield potential. She then converted these estimates of tons of corn into volumes of corn, using the standardized metric that one bushel of corn weighs 56 pounds (Rankin 2009), and calculated a cone with this estimated volume and a radius of 300 m.
Animation
Nebhut created the animations on 3ds Max 2022 (Autodesk, San Rafael, CA), with a to-scale model of Indianapolis (Dmitriy 2021) overlaying natural-color orthophotographs of Marion, Hamilton, Clinton, Hendricks, Boone, Tiptop, Madison, and Hancock Counties from the IndianaMap Orthophotography Project (IndianaMap Framework Data 2005). She rendered the final images with Corona Renderer 7 (Chaos Czech, Prague, Czech Republic), then edited the video in After Effects CS6 (Adobe, San Jose, CA) to add labels, color correction, and noise reduction.
Works Cited
Bowling, L.C., Cherkauer, K.A., Lee, C.I., Beckerman, J.L., Brouder, S., Buzan, J.R., Doering, O.C., Dukes, J.S., Ebner, P.D., Frankenberger, J.R. and Gramig, B.M., 2020. Agricultural impacts of climate change in Indiana and potential adaptations. Climatic Change, 163(4), pp.2005-2027.
Dmitriy, G. (2021). Cityscape Indianapolis USA 3D model.
EIA (2021). Indiana State Profile and Energy Estimates: Indiana Net Electricity Generation By Source, May 2021.
EPA (2019). Inventory of U.S. Greenhouse Gas Emissions and Sinks 1990-2018. (No. EPA 430-R-18-003). Washington, D.C.: U.S. Environmental Protection Agency.
Houser, M., Sandweiss, E., Gazley, B., Grennan Browning, E., Reynolds, H., Shanahan, S. (2019). The Hoosier Life Survey: Assessing Hoosier Preparedness for Environmental Change, Extreme Weather, and Other Risks. Indiana University Environmental Resilience Institute, Indiana University. Bloomington, Indiana.
IndianaMap Framework Data (2005). 2005 IndianaMap Natural Color Orthophotography.
Nderitu, D., Gotham, D., Lu, L., Mize, D., Phillips, T., Preckel, P., Velastegui, M., Wu, F. (2017). 2017 Indiana Renewable Energy Resources Study. State Utility Forecasting Group, Energy Center, Purdue University. West Lafayette, Indiana.
Rankin, M. (2009). Understanding Corn Test Weight. Division of Cooperative Extension of the University of Wisconsin-Extension. Madison, Wisconsin.
USCB (2021). State Population Totals: 2010-2020. Table: Annual Estimates of the Resident Population for the United States, Regions, States, the District of Columbia, and Puerto Rico: April 1, 2010 to July 1, 2019; April 1, 2020; and July 1, 2020 (NST-EST2020).
USDA (2018). 2017 Census of Agriculture, Table 25. Field Crops: 2017 and 2012.
USDA (2021a). Farm Income and Wealth Statistics: Cash receipts by commodity, State ranking, 2020.
USDA (2021b). 2020 State Agricultural Overview: Indiana. Crops - Planted, Harvested, Yield, Production, Price (MYA), Value of Production, Sorted by Value of Production in Dollars.
Widhalm, M., Hamlet, A. Byun, K., Robeson, S., Baldwin, M., Staten, P., Chiu, C., Coleman, J., Hall, E., Hoogewind, K., Huber, M., Kieu, C., Yoo, J., Dukes, J.S. (2018). Indiana’s Past & Future Climate: A Report from the Indiana Climate Change Impacts Assessment.
Purdue Climate Change Research Center, Purdue University. West Lafayette, Indiana. DOI: 10.5703/1288284316634