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Abstract The U.S. water supply and carbon sequestration are increasingly threatened by future climate change and air pollution. This study investigates the ecohydrological responses to the individual and combined impacts of climate change and anthropogenic emission (referring only to air pollutants, excluding greenhouse gases) changes at two spatial scales by coupling a regional online‐coupled meteorology and chemistry model (WRF‐Chem) and a water balance model (WaSSI). Combined effects of climate change and anthropogenic emission changes in 2046–2055 relative to 2001–2010 over the US enhance hydrological cycle and carbon sequestration. However, a drying trend occurs in the central and part of the western U.S. Climate change is projected to dominate the ecohydrological changes in most regions. Anthropogenic emission changes under 2001–2010 climate conditions cools down inland water resource regions with 0.01–0.15°C, moisturizes the east and dry the west U.S. More stringent anthropogenic emission control enhances precipitation and ecosystem production in the east and west but has an opposite trend in the central U.S. The ecohydrological modeling in California and North Carolina based on 4‐km resolution meteorological data in 2050 and 2005 shows varying changes in magnitudes and spatial patterns compared to results based on 36‐km resolution meteorological data. Projected changes in air pollutant emissions may accelerate climatic warming in coastal areas and the state of New Mexico and decrease precipitation, runoff, and carbon sequestration in part of the western U.S. Strategies to address future possible problems such as heatwaves, water stress, and ecosystem productivity should consider the varying interplay between air quality control and climate change at different spatial scales.
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Climate Change Impacts on Eastern Boundary Upwelling Systems
The world's eastern boundary upwelling systems (EBUSs) contribute disproportionately to global ocean productivity and provide critical ecosystem services to human society. The impact of climate change on EBUSs and the ecosystems they support is thus a subject of considerable interest. Here, we review hypotheses of climate-driven change in the physics, biogeochemistry, and ecology of EBUSs; describe observed changes over recent decades; and present projected changes over the twenty-first century. Similarities in historical and projected change among EBUSs include a trend toward upwelling intensification in poleward regions, mitigatedwarming in near-coastal regions where upwelling intensifies, and enhanced water-column stratification and a shoaling mixed layer. However, there remains significant uncertainty in how EBUSs will evolve with climate change, particularly in how the sometimes competing changes in upwelling intensity, source-water chemistry, and stratification will affect productivity and ecosystem structure. We summarize the commonalities and differences in historical and projected change in EBUSs and conclude with an assessment of key remaining uncertainties and questions. Future studies will need to address these questions to better understand, project, and adapt to climate-driven changes in EBUSs.
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- Award ID(s):
- 1637632
- PAR ID:
- 10431834
- Date Published:
- Journal Name:
- Annual Review of Marine Science
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 1941-1405
- Page Range / eLocation ID:
- 303 to 328
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1146/annurev-marine-032122-021945
