ICS CAS Invited Lecture in Statistical and Environmental Modelling

Did the Paris Climate Agreement Work? Evidence from Bayesian Integrated Assessment

Speaker: Adrian E. Raftery, University of Washington
Date and time: Tuesday, November 25, 2025 (15:00 PM CET)
Place: Online or at ICS CAS room 318, Pod Vodárenskou věží 2, Prague 8.
Registration: Please register for the event via this survey.

Projecting future climate change is important for implementing the 2015 Paris Agreement, which aims to limit greenhouse gas emissions to a level that would keep global average temperature increase to 2100 below 1.5°C, and in any event well below 2°C. The Intergovernmental Panel on Climate Change uses emissions scenarios for projecting climate change, but since 2017 an alternative fully statistical Bayesian probabilistic approach has been developed. This relies on the IPAT equation that expresses emissions as the product of population, Gross Domestic Product (GDP) per capita, and carbon intensity, namely carbon emissions per unit of GDP. Here we use data on population, GDP and emissions for 2015-2024 to assess probabilistically the changes in climate change prospects associated with post-Paris emissions.

Jiang, J., Shi, S., & Raftery, A. E. (2025). Mitigation efforts to reduce carbon dioxide emissions and meet the Paris Agreement have been offset by economic growth. Communications Earth & Environment, 6(1), 823. https://doi.org/10.1038/s43247-025-02743-x, also see this link.

Adrian Raftery

Adrian Raftery is the Blumstein–Jordan Professor Emeritus of Statistics and Sociology at the University of Washington. He was the founding director of the Center for Statistics and the Social Sciences (CSSS) and is currently a faculty affiliate of both CSSS and the Center for Studies in Demography and Ecology. His research focuses on developing new statistical methods for the social and environmental sciences. An elected member of the U.S. National Academy of Sciences, he was recognized by Thomson-ISI as the world’s most cited researcher in mathematics during the decade 1995–2005. Professor Raftery has supervised 36 Ph.D. students, 21 of whom have held tenure-track faculty positions. Altogether, he has 170 academic descendants

Seminar in Statistical Modelling

Probabilistic Subnational Population Projections

Speaker: Hana Ševčíková, University of Washington
Date and time: Friday, December 5, 2025 (10:00 AM CET)
Place: Online or at ICS CAS room 318, Pod Vodárenskou věží 2, Prague 8.

Abstract:

Population projections provide predictions of future population sizes for an area. Historically, most existing population projections have been produced using deterministic or scenario-based approaches, and did not assess uncertainty about future population change. Starting in 2015, however, the United Nations has produced probabilistic population projections for all countries using a Bayesian approach. There is also considerable interest in subnational probabilistic population projections, for example at the state and county levels. These are needed by local governments for planning, by the private sector for strategic decision-making, and by researchers, particularly in the health and social science research on subnational variation and inequality. A direct application of the UN approach to the subnational context has not turned out to be fully satisfactory, because within-country correlations in fertility and mortality are generally larger than between-country ones, migration is not constrained in the same way, and there is a need to account for college and other special populations, particularly at the county level. We propose an extension to the national framework that deals with these challenges and gives accurate and well-calibrated forecasts and forecast intervals.

References:

Yu, C., Ševčíková, H., Raftery, A.E., and Curran, S.R. (2023). Probabilistic County-Level Population Projections. Demography, Vol. 60(3): 915-937.

Ševčíková, H., Raftery, A.E. and Gerland, P. (2018). Probabilistic projection of subnational total fertility rates. Demographic Research, Vol. 38(60): 1843-1884.

Ševčíková, H. and Raftery, A.E. (2021). Probabilistic Projection of Subnational Life Expectancy. Journal of Official Statistics, Vol. 37, no. 3, 591-610.

Azose, J.J., Ševčíková, H., Raftery, A.E. (2016): Probabilistic population projections with migration uncertainty. Proceedings of the National Academy of Sciences 113:6460–6465.

More project publications at: https://bayespop.csss.washington.edu/papers

Hana Ševčíková

https://sites.stat.washington.edu/hana/

Hana Ševčíková is a senior research scientist in the Center for Studies in Demography and Ecology at the University of Washington. She works on developing methods for probabilistic population projection, national and subnational. She has developed various demographic R packages that the United Nations Population Division has been using to produce the World Population Prospects. She also works as a data scientist on land use modeling for the Puget Sound Regional Council in Seattle.