Whereas the population is expected to decrease somewhat until 2100 in Asia, Europe, and South America, it is predicted to grow significantly in Africa. While there were 1.5 billion inhabitants on the continent at the beginning of 2024, the number of inhabitants is expected to reach 3.8 billion by 2100. In total, the global population is expected to reach nearly 10.4 billion by 2100. Worldwide population In the United States, the total population is expected to steadily increase over the next couple of years. In 2024, Asia held over half of the global population and is expected to have the highest number of people living in urban areas in 2050. Asia is home to the two most populous countries, India and China, both with a population of over one billion people. However, the small country of Monaco had the highest population density worldwide in 2021. Effects of overpopulation Alongside the growing worldwide population, there are negative effects of overpopulation. The increasing population puts a higher pressure on existing resources and contributes to pollution. As the population grows, the demand for food grows, which requires more water, which in turn takes away from the freshwater available. Concurrently, food needs to be transported through different mechanisms, which contributes to air pollution. Not every resource is renewable, meaning the world is using up limited resources that will eventually run out. Furthermore, more species will become extinct which harms the ecosystem and food chain. Overpopulation was considered to be one of the most important environmental issues worldwide in 2020.

By the end of 2100, the population of Central and Eastern Europe will amount to 187.07 million, a decrease of 43 percent from 2017. If Russia is excluded from the tally, the CEE population will decrease by more than half. Latvia will lose the most population, nearly 80 percent. Russia, on the other hand, will experience the smallest decline (-27 percent).

The Georeferenced U.S. County-Level Population Projections, Total and by Sex, Race and Age, Based on the SSPs, 2020-2100 consists of county-level population projection scenarios of total population, and by age, sex, and race in five-year intervals for all U.S. counties for the period 2020 - 2100. These data have numerous potential uses and can serve as inputs for addressing questions involving sub-national demographic change in the United States in the near, middle- and long-term.

Before 2025, the world's total population is expected to reach eight billion. Furthermore, it is predicted to reach over 10 billion in 2060, before slowing again as global birth rates are expected to decrease. Moreover, it is still unclear to what extent global warming will have an impact on population development. A high share of the population increase is expected to happen on the African continent.

Algeria DZ: Population Projection: Mid Year data was reported at 77,291,555.000 Person in 2100. This records an increase from the previous number of 77,271,969.000 Person for 2099. Algeria DZ: Population Projection: Mid Year data is updated yearly, averaging 47,735,685.000 Person from Jun 1950 (Median) to 2100, with 151 observations. The data reached an all-time high of 77,291,555.000 Person in 2100 and a record low of 8,892,718.000 Person in 1950. Algeria DZ: Population Projection: Mid Year data remains active status in CEIC and is reported by U.S. Census Bureau. The data is categorized under Global Database’s Algeria – Table DZ.US Census Bureau: Demographic Projection.

Africa's population is projected to grow significantly in the coming years. Estimates conducted in July 2020 show that Nigeria, the most populous country on the continent, would reach around *** million inhabitants by 2100. Compared to 2021, when the country counted *** million people, this would represent an impressive growth of around *** percent. The Democratic Republic of the Congo is estimated to be the second most populous nation on the African continent, reaching *** million individuals. According to the study, nine countries in Africa would exceed 100 million people by 2100.

County population projections broken down by year, age, race, and gender (2020-2100) for use with GIS mapping software, databases, and web applications.

The methodology used to produce these projections differs from ICLUS v2.0 (https://cfpub.epa.gov/ncea/iclus/recordisplay.cfm?deid=322479). The demographic components of change (i.e., rates of fertility and mortality) for ICLUS v2.1 were taken directly from the Wittgenstein Centre Data Explorer (http://witt.null2.net/shiny/wic/). These projections were produced more recently than the Census projections used in ICLUS v2.0, and incorporate more recent observations of population change. SSP2 is a “middle-of-the-road” projection, where social, economic and technological trends do not shift markedly from historical patterns, resulting in a U.S. population of 455 million people by 2100. Domestic migration trends remain largely consistent with the recent past, however the amenity value of local climate (average precipitation and temperature for summer and winter) is used in ICLUS v2.1.1 to influence migration patterns. The name of the climate model used as the source of future climate patterns is included at the end of the file name (e.g., "GISS-E2-R" or "HadGEM2-ES"). The approach for incorporating climate change into the migration model is described in the ICLUS v2.0 documentation. The SSP5 narrative describes a rapidly growing and flourishing global economy that remains heavily dependent on fossil fuels, and a U.S. population that exceeds 730 million by 2100. ICLUS v2.1 land use projections under SSP5 result in a considerably larger expansion of developed lands relative to SSP2. The the amenity value of local climate (average precipitation and temperature for summer and winter) is used in ICLUS v2.1.1 to influence migration patterns. The name of the climate model used as the source of future climate patterns is included at the end of the file name (e.g., "GISS-E2-R" or "HadGEM2-ES"). The approach for incorporating climate change into the migration model is described in the ICLUS v2.0 documentation. RCP4.5 assumes that global greenhoue gas emissions increase into the latter part of the century, before leveling off and eventually stabilizing by 2100 as a result of various climate change policies. RCP8.5 assumes that global greenhoue gas emissions increase through the year 2100.

Armenia AM: Population Projection: Mid Year data was reported at 1,293,680.000 Person in 2100. This records a decrease from the previous number of 1,312,746.000 Person for 2099. Armenia AM: Population Projection: Mid Year data is updated yearly, averaging 2,587,339.000 Person from Jun 1950 (Median) to 2100, with 151 observations. The data reached an all-time high of 3,655,035.000 Person in 1988 and a record low of 1,293,680.000 Person in 2100. Armenia AM: Population Projection: Mid Year data remains active status in CEIC and is reported by U.S. Census Bureau. The data is categorized under Global Database’s Armenia – Table AM.US Census Bureau: Demographic Projection.

Algeria DZ: Population Projection: Mid Year: Growth data was reported at 0.020 % in 2100. This records a decrease from the previous number of 0.040 % for 2099. Algeria DZ: Population Projection: Mid Year: Growth data is updated yearly, averaging 1.105 % from Jun 1987 (Median) to 2100, with 114 observations. The data reached an all-time high of 2.820 % in 1987 and a record low of 0.020 % in 2100. Algeria DZ: Population Projection: Mid Year: Growth data remains active status in CEIC and is reported by U.S. Census Bureau. The data is categorized under Global Database’s Algeria – Table DZ.US Census Bureau: Demographic Projection.

Climate and land-use change are major components of global environmental change with feedbacks between these components. The consequences of these interactions show that land use may exacerbate or alleviate climate change effects. Based on these findings it is important to use land-use scenarios that are consistent with the specific assumptions underlying climate-change scenarios. The Integrated Climate and Land-Use Scenarios (ICLUS) project developed land-use outputs that are based on a downscaled version of the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) social, economic, and demographic storylines. ICLUS outputs are derived from a pair of models. A demographic model generates county-level population estimates that are distributed by a spatial allocation model (SERGoM v3) as housing density across the landscape. Land-use outputs were developed for the four main SRES storylines and a baseline ("base case"). The model is run for the conterminous USA and output is available for each scenario by decade to 2100. In addition to housing density at a 1 hectare spatial resolution, this project also generated estimates of impervious surface at a resolution of 1 square kilometer. This shapefile holds population data for all counties of the conterminous USA for all decades (2010-2100) and SRES population growth scenarios (A1, A2, B1, B2), as well as a 'base case' (BC) scenario, for use in the Integrated Climate and Land Use Scenarios (ICLUS) project.

Future county population was based on projections for 2100 from the Spatially Explicit Regional Growth Model (SERGoM; Theobald 2005). SERGoM simulates population based on existing patterns of growth by census block, groundwater well and road density, and transportation distance to urban areas, while constraining the pattern of development to areas outside of protected areas and urban areas (Theobald 2005). The dataset here is a projection for a “baseline” growth scenario that assumes a similar trajectory to that of current urban growth (Bierwagen et al. 2010). SERGoM accuracy is estimated as 79–99% when compared to 1990 and 2000 census data, with the accuracy varying by urban/exurban/rural categories and increasing slightly with coarser resolution (Theobald 2005). The accuracy of future model predictions with different economic scenarios is most sensitive to fertility rates, which are subject to cultural change, economic recessions, and the current pattern of lands protected from development (Bierwagen et al. 2010). Bierwagen, B. G., D. M. Theobald, C. R. Pyke, A. Choate, P. Groth, J. V. Thomas, and P. Morefield. 2010. National housing and impervious surface scenarios for integrated climate impact assessments. Proceedings of the National Academy of Sciences of the United States of America 107:20887-20892. Theobald, D. M. 2005. Landscape patterns of exurban growth in the USA from 1980 to 2020. Ecology and Society 10: article 32.

General Information

The Pop-AUT database was developed for the DISCC-AT project, which required subnational population projections for Austria consistent with the updated Shared Socio-Economic Pathways (SSPs). For this database, the most recent version of the nationwide SSP population projections (IIASA-WiC POP 2023) are spatially downscaled, offering a detailed perspective at the subnational level in Austria. Recognizing the relevance of this information for a wider audience, the data has been made publicly accessible through an interactive dashboard. There, users are invited to explore how the Austrian population is projected to evolve under different SSP scenarios until the end of this century.

Methodology

The downscaling process of the nationwide Shared Socioeconomic Pathways (SSP) population projections is a four-step procedure developed to obtain subnational demographic projections for Austria. In the first step, population potential surfaces for Austria are derived. These indicate the attractiveness of a location in terms of habitability and are obtained using machine learning techniques, specifically random forest models, along with geospatial information such as land use, roads, elevation, distance to cities, and elevation (see, e.g., Wang et al. 2023).

The population potential surfaces play a crucial role in distributing the Austrian population effectively across the country. Calculations are based on the 1×1 km spatial resolution database provided by Wang et al. (2023), covering all SSPs in 5-year intervals from 2020 to 2100.

Moving to the second step, the updated nationwide SSP population projections for Austria (IIASA-WiC POP 2023) are distributed to all 1×1 km grid cells within the country. This distribution is guided by the previously computed grid cell-level population potential surfaces, ensuring a more granular representation of demographic trends.

The base year for all scenarios is 2015, obtained by downscaling the UN World Population Prospects 2015 count for Austria using the WorldPop (2015) 1×1 km population count raster.

In the third step, the 1×1 km population projections are temporally interpolated to obtain yearly projections for all SSP scenarios spanning the period from 2015 to 2100.

The final step involves the spatial aggregation of the gridded SSP-consistent population projections to the administrative levels of provinces (Bundesländer), districts (Bezirke), and municipalities (Gemeinden).

Dashboard

The data can be explored interactively through a dashboard.

Data Inputs

Updated nationwide SSP population projections: IIASA-WiC POP (2023) (https://zenodo.org/records/7921989)

Population potential surfaces: Wang, X., Meng, X., & Long, Y. (2022). Projecting 1 km-grid population distributions from 2020 to 2100 globally under shared socioeconomic pathways. Scientific Data, 9(1), 563.

Shapefiles: data.gv.at

WorldPop 2015: WorldPop (www.worldpop.org - School of Geography and Environmental Science, University of Southampton; Department of Geography and Geosciences, University of Louisville; Departement de Geographie, Universite de Namur) and Center for International Earth Science Information Network (CIESIN), Columbia University (2018). Global High Resolution Population Denominators Project - Funded by The Bill and Melinda Gates Foundation (OPP1134076). https://dx.doi.org/10.5258/SOTON/WP00647

Version

This is version 1.0, built upon the Review-Phase 2 version of the updated nationwide SSP population projections (IIASA-WiC POP 2023). Once these projections are revised, this dataset will be accordingly updated.

File Organization

The SSP-consistent population projections for Austria are accessible in two formats: .csv files for administrative units (provinces = Bundesländer, districts = Politische Bezirke, municipalities = Gemeinden) and 1×1 km raster files in GeoTIFF and NetCDF formats. All files encompass annual population counts spanning from 2015 to 2100.

Australia Population Projection: Mid Year: Growth data was reported at 0.300 % in 2100. This stayed constant from the previous number of 0.300 % for 2099. Australia Population Projection: Mid Year: Growth data is updated yearly, averaging 0.750 % from Jun 1986 (Median) to 2100, with 115 observations. The data reached an all-time high of 2.230 % in 2008 and a record low of 0.300 % in 2100. Australia Population Projection: Mid Year: Growth data remains active status in CEIC and is reported by U.S. Census Bureau. The data is categorized under Global Database’s Australia – Table AU.US Census Bureau: Demographic Projection.

The Georeferenced U.S. County-Level Population Projections, Total and by Sex, Race and Age, Based on the SSPs, 2020-2100 consists of county-level population projection scenarios of total population, and by age, sex, and race in five-year intervals for all U.S. counties for the period 2020 - 2100. These data have numerous potential uses and can serve as inputs for addressing questions involving sub-national demographic change in the United States in the near, middle- and long-term.

The Global Population Projection Grids Based on Shared Socioeconomic Pathways (SSPs), Downscaled 1-km Grids, 2010-2100 consists of global spatial population projections at a resolution of 1-km (about 30 arc-seconds) for urban, rural, and total population, and at ten-year intervals for 2010-2100. The projections are consistent both quantitatively and qualitatively with the Shared Socioeconomic Pathways (SSPs). This data set is a downscaled version of the Global Population Projection Grids Based on SSPs, v1 (2010-2100), published in Jones and O'Neill (2016). The downscaling methods were published in Gao (2017). Spatial demographic projections are key inputs for the analysis of land use, energy use, and emissions, as well as for the assessment of climate change vulnerability, impacts, and adaptation. The SSPs are developed to support future climate and global change research and the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6). This data set is distributed in GeoTIFF and netCDF formats.

The Global Population Projection Grids Based on Shared Socioeconomic Pathways (SSPs), 2010-2100 consists of global spatial population projections at a resolution of one-eighth degree (7.5 arc-minutes) for urban, rural, and total population, consistent both quantitatively and qualitatively, with the SSPs at ten-year intervals for 2010-2100. Spatial demographic projections are key inputs for the analysis of land use, energy use, and emissions, as well as for the assessment of climate change vulnerability, impacts, and adaptation. The SSPs are developed to support future climate and global change research and the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6). This data set is produced based on a clear need for plausible alternative projections of spatial distribution of the population that can represent patterns of development consistent with the SSPs.

Belarus BY: Population Projection: Mid Year data was reported at 6,181,724.000 Person in 2100. This records a decrease from the previous number of 6,215,488.000 Person for 2099. Belarus BY: Population Projection: Mid Year data is updated yearly, averaging 8,784,282.000 Person from Jun 1950 (Median) to 2100, with 151 observations. The data reached an all-time high of 10,250,139.000 Person in 1993 and a record low of 6,181,724.000 Person in 2100. Belarus BY: Population Projection: Mid Year data remains active status in CEIC and is reported by U.S. Census Bureau. The data is categorized under Global Database’s Belarus – Table BY.US Census Bureau: Demographic Projection.

Until 2100, the world's population is expected to be ageing. Whereas people over 60 years made up less than 13 percent of the world's population in 2024, this share is estimated to reach 28.8 percent in 2100. On the other hand, the share of people between zero and 14 years was expected to decrease by almost ten percentage points over the same period.

The population of Europe is expected to fall from 740.6 million in 2023 to just 586.5 million people by 2100, in the medium-variant scenario provided in this projection. In the scenario where the population declines even further, the population of Europe may fall to as low as 401.2 million by 2100, while in the high-variant projection, the population will increase to approximately 830.6 million.