As the Chornobyl (Chernobyl) nuclear disaster reaches its 37th anniversary, HURI’s MAPA team continues to expand its interactive resource on the explosion and its aftermath.
On April 26, 1986, Reactor No. 4 of the Chornobyl Nuclear Power Plant in Soviet Ukraine exploded, creating the worst nuclear disaster in history. Unleashing more radiation than several hundred atomic bombs, the incident contaminated 20,000 square miles of land in Ukraine, while the radioactive plume spread across Europe. A late response from Moscow only exacerbated the situation. In the first week, 90,000 people were displaced and tens of millions affected by the radiation. The effects of Chornobyl, felt in myriad ways, will continue for years to come.
The MAPA: Digital Atlas of Ukraine Chernobyl/ Chornobyl Project brings innovative geospatial analysis to the study of the accident's environmental and human impact. It takes advantage of methods used in the field of integrative geography, which looks at the spatial aspects of the interaction between human societies and their environment. MAPA seeks to inform the general public about the effects of nuclear disasters and offers a unique opportunity to engage the fields of medicine, demography, ecology, and history from a digital humanities perspective. The project was launched in April 2021. Since that time, the team has continued to add data that researchers can view spatially and compare to other variables.
In particular, recent additions include new data in the Morbidity, Irradiation (radiation exposure), and Contamination sections on the regional, district, and settlement levels. These data are provided in the form of map layers that researchers can apply to a base map of Ukraine. The team has also begun to analyze the maps now that a significant amount of data has been added to the atlas.
The MAPA Chernobyl/Chornobyl Project team comprises Kostyantyn Bondarenko, MAPA Project Manager, Natalia Levchuk, MAPA project associate and a leading Ukrainian demographer working on data acquisition and data analysis for the project, and Serhii Plokhii, HURI Director and author of Chernobyl: The History of a Nuclear Catastrophe. This year, the team welcomed an additional member, Sonya Gupta, a first-year graduate student (G1) at Harvard University in the Regional Studies - Russia, Eastern Europe, and Central Asia (REECA) program. A self-taught GIS user, Sonya has spent the last few years using GIS to improve health equity and teaching GIS to community members and students to better understand health disparities. She first became involved with MAPA while taking Plokhii’s History of Ukraine course and is now a research assistant for the project, where she explores ways to expand medical and socioeconomic analyses using a geospatial approach.
A Closer Look at MAPA’s Latest Chornobyl Data
“Together with our partners in Ukraine, we are currently completing a key stage of the project, collecting and mapping data on the short-term and long-term impact of the disaster,” Plokhii said. “This is a highly original component of the project which will present for the first time the spatial dimension of the health consequences of Chornobyl. We are excited to share that information with the visitors of our site.”
Over the past year, the MAPA team focused on three important aspects: radioactive contamination, irradiation, and public health indicators.
The greatly expanded “Contamination” section provides information about the ground deposition of the major radionuclides of concern: cesium-134 and cesium-137, strontium-90, and iodine-131. This section has been supplemented with maps tracing these values over the years, from 1986 to 2020. “Importantly, these maps are based on very detailed data – data for 22,688 settlements covering the whole territory of Ukraine,” Levchuk noted. This detailed information allows for more nuanced analysis of the spread of radiation and its impact on Ukraine’s population and ecology.
Ground deposition values can be compared to the spatial distribution of contaminated products, such as milk, which further affected human exposure (irradiation). For the radioactively contaminated districts, for example, MAPA includes detailed information about cesium in milk from 1991 to 2005.
The Irradiation block includes data on the intake of iodine-131, such as through consumption of contaminated milk. The data show variations of thyroid doses by sex and age (including children of different ages, teens, and adults) across the territory of Ukraine, and the maps provide evidence supporting the correlation between iodine intake and thyroid cancer. “Comparing hot spots of iodine exposure with the map of the incidence rate of thyroid cancer, one can notice some similarities in terms of their geographical location,” Levchuk explained.
“We also expanded our block on morbidity, but this section is limited when it comes to district-level data,” Levchuk said. “This is because health data at the local level are rather rare and not available in Ukraine.” Nonetheless, maps show regional discrepancies in life expectancy.
Although we cannot yet be sure what factors influence mortality differences, it is worth exploring further whether the long-term health effects of the Chornobyl accident along with its adverse social and economic impacts could play a role.
How GIS Helps Uncover New Understandings of the Chornobyl Disaster
Visualizing these sets of data on the map of Ukraine helps to uncover patterns and deviations that subsequently can inform our understanding of Chornobyl’s short-term and long-term impact.
The maps below show large variations in the cesium-137 ground deposition across the territory of Ukraine in 1986 and 2020.
By 2020, 34 years after the accident, the situation improved, partly due to natural decay processes and partly due to decontamination measures introduced. However, as the 2020 map reveals, there are still some areas with high contaminations. Persistent control and monitoring of these areas are needed to reduce human exposure.
Interestingly, not all of the radioactive isotopes were deposited in the same way: most of the cesium-contaminated areas are concentrated to the west of the Chornobyl plant and to a lesser extent to the south, whereas strontium clearly flowed southward from Chornobyl.
Insights such as these become evident when the data are mapped spatially, clearly showing trends and variations that can be compared at a glance with other factors. “Incorporating a geospatial component into our analysis proved to be critical in understanding the effects of the Chernobyl disaster on the health of the population,” Sonya said. “One particularly fascinating discovery was a relationship between migration patterns after the accident, socioeconomic factors, and morbidity rates for specific cancers and diseases.”
MAPA: An Open-Access Research Tool
MAPA: Digital Atlas of Ukraine is an online resource that is free and available to anyone to use. Scholars, journalists, the general public, and students at all levels working on research projects can use MAPA to complement their work and to seek new insights as they ask research questions.
“It's an interactive platform designed to allow students to conduct their own analyses, just like I did for my final paper in Professor Plokhii's course,” Sonya said. “By incorporating data from other fields like sociology or economics, students can use the maps and data to enhance their own projects.”
“Best of all,” Sonya added, “it's a straightforward process to integrate the maps and data into your work.” People using MAPA can generate image files of the mapped data, allowing them to include the illustration in their paper or presentation.
MAPA has a number of user guides, classroom lesson plans, and tutorials to help people get started with using the digital atlas. Contact Kostyantyn Bondarenko at kbondar@fas.harvard.edu if you have questions.
What’s Next for the MAPA Chernobyl/Chornobyl Project
In addition to further complementing the block on morbidity data and extensively expanding the block on population resettlements, the MAPA Chernobyl/Chornobyl Project is now shifting to focus on the political and social factors that have influenced the consequences of the accident.
The team is working with the Laboratory for Medical Demography, National Center for Radiation Medicine of Ukraine to obtain migration and resettlement data and with the Canter Registry of Ukraine to obtain additional data on cancer statistics. This information will enhance the interactive web map, providing a rich resource for further research.
The team will present the project and some initial findings at the 2023 ASEEES Convention in Philadelphia, Pennsylvania.