IMPACTS develops and deploys solutions to understand who and where is most affected by the climate crisis to inform targeted and equitable responses for vulnerable populations and places.

As the world mobilizes to respond to the inequitable effects of climate and environmental change, integrated assessment models of climate risk must include detailed indicators of the social and geographic vulnerability of human societies.

Demographic projections are a key building block of the models we need to predict future energy and end-use emissions, land use patterns, and to identify hotspots of climate risk. However, current projections are inadequate because they fail to disaggregate results for specific sub-populations or regions within countries.

Experts across different scientific disciplines need demographic projections that use a standardized and established modelling framework. The Intergovernmental Panel on Climate Change (IPCC) is building a global body of evidence that includes modeling of future climate and population dynamics. To close the feedback loop between population and climate change, researchers use an interlinked framework based on socioeconomic scenarios called the Shared Socio-economic Pathways (SSPs). Each offers a different economic, technological, and social pathway that the world could take.

IMPACTS—a project of the Population Council’s Population, Environmental Risks, and the Climate Crisis Initiative (PERCC)—leverages complex computational technologies, such as machine learning and geospatial analysis, to process the diverse data needed to model climate change and population dynamics. IMPACTS includes:

Community Demographic Model (CDM)

The Community Demographic Model (CDM) is a system of scientifically rigorous modules that project SSP-consistent demographic data at fine spatial resolution and disaggregated by key population characteristics. Our projections can equip IPCC, scientists, experts, businesses and decision-makers with the robust data and tools they need to act and design climate policies customized to specific geographies and peoples’ diverse characteristics and living conditions. The CDM is being expanded to:

  • Geographic expansion: Extending the CDM to more countries and individual US cities.
  • Population characteristics: Disaggregate future populations across more characteristics of vulnerability, e.g., age, gender, education, poverty, ethnicity.
  • Fill data gaps: Use machine learning and other tools to adapt the CDM for data sparseenvironments lacking the conventional inputs for demographic models.

Connections and Assessments

CDM has been used to inform the SSP’s and have been used to examine the effects of population change on land-use, energy consumption and emissions. We have modeled how temperature affects migration patterns.

  • Identify hotspots of climate risk integrate our demographic projections with climate data to identify the geographic regions with the highest vulnerability to environmental hazards such as heat waves or droughts, allowing for targeted interventions and policies.
  • Predict energy and end-use emissions In high emissions countries, such as India, the CDM can be integrated with localized models of energy demands and emissions to inform targeted mitigation policies.
  • Coupled Systems using demographic projections and energy and emissions projections to inform Integrated Assessment Models of climate and environmental change.

Global User Network

IMPACTS assembles and equips a global user network to deploy the CDM for research and policy around the world. Key activities include:

  • User-friendly, interactive webpage all data and models accessible and freely available for users and stakeholders to visualize projections, integrate them with other models, and use results to define policy.
  • Research translation to assist users to effectively interpret and disseminate evidence inaccessible and tailored formats for an inclusive and cross-sectoral audience and coalition.
  • Capacity building including trainings and workshops, to grow the global user network to include actors from more sectors and build the capacity of the next generation of researchers, particularly those from underrepresented groups and geographies.

Collaborate with Population Council researchers and partners on our IMPACTS project. Contact us: