Lee et al. (2025) Multi-centennial climate change in a warming world beyond 2100

Identification

• Journal: Earth System Dynamics
• Year: 2025
• Date: 2025-09-09
• Authors: Sun‐Seon Lee, Sahil Sharma, Nan Rosenbloom, Keith B. Rodgers, Ji‐Eun Kim, Eun Young Kwon, Christian L. E. Franzke, In‐Won Kim, Mohanan Geethalekshmi Sreeush, Karl Stein
• DOI: 10.5194/esd-16-1427-2025

Research Groups

• Center for Climate Physics, Institute for Basic Science, Busan, Republic of Korea
• Pusan National University, Busan, Republic of Korea
• National Center for Atmospheric Research, Boulder, CO, USA
• WPI-Advanced Institute for Marine Ecosystem Change, Tohoku University, Sendai, Japan
• Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany

Short Summary

A new 10-member ensemble simulation with the state-of-the-art Earth system model was employed to study the long-term climate response to sustained greenhouse warming through to the year 2500. The findings show that the projected changes in the forced mean state and internal variability during 2101–2500 differ substantially from the 21st-century projections, emphasizing the importance of multi-century perspectives for understanding future climate change and informing effective mitigation strategies.

Objective

• To examine multi-centennial climate change, including mean state and variability, in a warming world beyond 2100 by extending 10 ensemble simulations of the Community Earth System Model 2 large ensemble (CESM2-LE) from 2101 to 2500 under the Shared Socio-economic Pathway (SSP)3-7.0 scenario, which involves the reduction of fossil and industrial CO2 emissions to zero by 2250.

Study Configuration

• Spatial Scale: Global, with nominal 1° × 1° spatial resolution. Regional analyses for megacities and latitudinal bands.
• Temporal Scale: 1850–2500 (651 years), with a focus on the extended period from 2101 to 2500.

Methodology and Data

• Models used: Community Earth System Model 2 large ensemble (CESM2-LE), including:
  • Atmospheric model: Community Atmosphere Model version 6 (CAM6)
  • Land model: Community Land Model Version 5 (CLM5)
  • Physical ocean model: Parallel Ocean Program version 2 (POP2)
  • Sea ice model: CICE Version 5.1.2 (CICE5)
  • Ocean ecosystem model: Marine Biogeochemistry Library (MARBL)
• Data sources:
  • Forcing: Extended SSP3-7.0 scenario (concentration-driven), with greenhouse gas concentrations from MAGICC7.0. Fossil and industrial CO2 emissions ramped down to zero by 2250.
  • Comparison/Validation: Global Precipitation Climatology Project (GPCP), observation-based ocean heat content (Ishii et al., 2017), observed sea ice extent (Fetterer et al., 2017), RAPID array observations for AMOC, HadCRUT4 for surface air temperature, CERES-EBAF for top-of-atmosphere radiative imbalance.

Main Results

• Temperature and Precipitation: Global mean surface air temperature perturbations exceed 12 °C by 2500 relative to 1850–2019. Global mean precipitation increases by 23.5% over 2401–2500 relative to 1979–2020. Pronounced warming (exceeding 28 °C) is projected over Nunavut, Canada, and high-latitude regions warm more substantially than low-latitude regions.
• Ocean and Sea Ice: Global ocean heat content in the upper 2000 m increases by approximately 17 000 ZJ by 2500. Arctic sea ice declines continuously to ice-free conditions after the mid-22nd century. The Atlantic Meridional Overturning Circulation (AMOC) slows until the late 22nd century, followed by a slight recovery.
• Carbon Cycle (Land): Substantial soil carbon release from permafrost thawing (Siberia and Canada) shifts land from a carbon sink to a carbon source after the 22nd century. Global terrestrial carbon stocks increase to 2288 PgC by 2200, then decrease to 2079 PgC by 2500.
• Carbon Cycle (Ocean): The ocean's capacity to absorb anthropogenic CO2 diminishes rapidly after the 21st century but remains a weakened carbon sink until 2500. The Southern Ocean's contribution to total carbon uptake increases from 25% to nearly 50% by 2500.
• Marine Ecosystems: Globally integrated ocean net primary productivity (NPP) declines by 12% from 48 PgC·yr⁻¹ in 1850 to 42 PgC·yr⁻¹ in 2500. Low-latitude marine primary production declines, linked to considerable depletion of dissolved inorganic phosphate (PO4) in the mesopelagic domain.
• Climate Variability: El Niño-Southern Oscillation (ENSO) variability is projected to diminish beyond the 21st century. Tropical intraseasonal variability, particularly the Madden-Julian Oscillation (MJO), notably strengthens, with precipitation spectral amplitude increasing approximately 10 times by the deep future.
• Seasonality: Substantial changes in the amplitude and timing of precipitation seasonality are projected at urban scales (e.g., Moscow: summer precipitation decreases, winter precipitation doubles, reversing wet summer/dry winter patterns; Mumbai: peak shifts from July to August with a nearly two-fold increase). The seasonal cycle amplitude of oceanic partial pressure of CO2 (pCO2) intensifies across most latitude bands, except for the tropics.

Contributions

• Provides a comprehensive overview of multi-centennial climate change (1850–2500) using a 10-member ensemble of the state-of-the-art CESM2-LE under the SSP3-7.0 scenario, extending beyond typical 21st-century projections.
• Demonstrates that post-2100 climate changes are not simple extrapolations of 21st-century trends, highlighting the unique long-term impacts of sustained anthropogenic forcing.
• Offers insights into both mean state shifts and changes in Earth system variability (e.g., ENSO weakening, MJO strengthening) across diverse temporal and spatial scales.
• Identifies critical long-term climate-carbon feedbacks, such as permafrost carbon release and shifts in oceanic carbon uptake contributions.
• Emphasizes the urgency of drastic carbon emission reductions and the need for long-term mitigation policies based on multi-centennial perspectives.

Funding

• Institute for Basic Science (grant no. IBS-R028-D1)

Citation

@article{Lee2025Multicentennial,
  author = {Lee, Sun‐Seon and Sharma, Sahil and Rosenbloom, Nan and Rodgers, Keith B. and Kim, Ji‐Eun and Kwon, Eun Young and Franzke, Christian L. E. and Kim, In‐Won and Sreeush, Mohanan Geethalekshmi and Stein, Karl},
  title = {Multi-centennial climate change in a warming world beyond 2100},
  journal = {Earth System Dynamics},
  year = {2025},
  doi = {10.5194/esd-16-1427-2025},
  url = {https://doi.org/10.5194/esd-16-1427-2025}
}