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Abstract Current‐generation climate models project that Africa will warm by up to 5°C in the coming century, severely stressing African populations. Past and ongoing work indicates, however, that the models used to create these projections do not match proxy records of past temperature in Africa during the mid‐Holocene (MH), raising concerns that their future projections may house large uncertainties. Rather than reproducing proxy‐based reconstructions of MH warming relative to the Pre‐Industrial (PI), models instead simulate MH temperatures very similar to or slightly colder than the PI. This data‐model mismatch could be due to a variety of factors, including biases in model surface energy budgets or inaccurate representation of the feedbacks between temperature and hydrologic change during the “Green Sahara.” We focus on the differences among model simulations in the Paleoclimate Modeling Intercomparison Project Phases 3 and 4 (PMIP3 and PMIP4), examining surface temperature and energy budgets to investigate controls on temperature and the potential model sources of this paleoclimate data‐model mismatch. Our results suggest that colder conditions simulated by PMIP3 and PMIP4 models during the MH are in large part due to the joint impacts of feedback uncertainties in response to increased precipitation, a strengthened West African Monsoon (WAM) in the Sahel, and the Green Sahara. We extend these insights into suggestions for model physics and boundary condition changes, and discuss implications for the accuracy of future climate model projections over Africa.
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This content will become publicly available on February 5, 2026
A Review of Processes and Models for the Export of Microplastics From Terrestrial to Aquatic Systems
ABSTRACT Microplastics have received increased attention due to their negative impacts on the environment and human health. To minimize these impacts, mitigation strategies that are efficient and cost‐effective for a range of plausible conditions need to be developed. Models can be used to support these mitigation‐related decisions. However, modeling studies related to the export of microplastics from terrestrial to aquatic systems have been limited. Here, we review such modeling studies, the trends over time and geography of focus, and discuss pertinent concepts and the underlying physical, chemical, and biological processes. We categorize the published modeling studies, discuss their limitations, and provide recommendations for future research to fill key knowledge gaps. Future modeling efforts should focus on collecting more comprehensive field data for validation, developing continuous models over event‐based, conducting experimental studies to better understand the fundamental processes, developing hybrid modeling frameworks, adopting sediment transport modeling approaches, incorporating land management practices in the models, integrating surface and sub‐surface processes at the watershed scale, and utilizing advanced data‐driven models like foundation models.
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- Award ID(s):
- 2305189
- PAR ID:
- 10578822
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- WIREs Water
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 2049-1948
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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