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Abstract Climate change poses significant threats to global agriculture, impacting food quantity, quality, and safety. The world is far from meeting crucial climate targets, prompting the exploration of alternative strategies such as stratospheric aerosol intervention (SAI) to reduce the impacts. This study investigates the potential impacts of SAI on rice and wheat production in India, a nation highly vulnerable to climate change given its substantial dependence on agriculture. We compare the results from the Assessing Responses and Impacts of Solar climate intervention on the Earth system with Stratospheric Aerosol Injection‐1.5°C (ARISE‐SAI‐1.5) experiment, which aims to keep global average surface air temperatures at 1.5°C above preindustrial in the Shared Socioeconomic Pathway 2‐4.5 (SSP2‐4.5) global warming scenario. Yield results show ARISE‐SAI‐1.5 leads to higher production for rainfed rice and wheat. We use 10 agroclimatic indices during the vegetative, reproductive, and ripening stages to evaluate these yield changes. ARISE‐SAI‐1.5 benefits rainfed wheat yields the most, compared to rice, due to its ability to prevent rising winter and spring temperatures while increasing wheat season precipitation. For rice, SSP2‐4.5 leads to many more warm extremes than the control period during all three growth stages and may cause a delay in the monsoon. ARISE‐SAI‐1.5 largely preserves monsoon rainfall, improving yields for rainfed rice in most regions. Even without the use of SAI, adaptation strategies such as adjusting planting dates could offer partial relief under SSP2‐4.5 if it is feasible to adjust established rice‐wheat cropping systems.
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Global and regional thermosteric and dynamic sea level change under stratospheric aerosol injection
Abstract Sea level rise (SLR) is a global concern in the era of climate change, prompting the exploration of interventions such as solar radiation modification through stratospheric aerosol injection (SAI). This intervention could affect the physical system in various ways. The present study analyzes the global and regional impacts of SAI using ARISE-SAI-1.5 (SAI-1.5) simulations with the Community Earth System Model 2. We calculated the regional thermosteric sea level under different scenarios. After validating our methodology for sea level components over the period 1995–2014, we determined changes in sea level variables under both SAI-1.5 and the underlying Shared Socioeconomic Pathway 2–4.5 (SSP2-4.5) relative to the reference period (1995–2014). In contrast to sea surface temperature, which under this SAI strategy should be maintained near 1.5 °C above preindustrial values, global SLR would continue increasing under SAI-1.5. However, SAI would significantly impact thermal expansion in SSP2-4.5 simulations, reducing the global long-term sea level trend from 3.7 ± 0.03 mm yr−1for SSP2-4.5–1.9 ± 0.04 mm yr−1for SAI-1.5, a 49% reduction. The associated ocean heat content is reduced from (2.0 ± 0.3) × 1022J yr−1under SSP2-4.5 to (1.17 ± 0.30) × 1022J yr−1under SAI, a 42% reduction. Additionally, SAI would impact the regional and global ocean by reducing the SLR rate. These findings underscore the potential of SAI as a climate intervention strategy with significant implications for sea level change.
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- Award ID(s):
- 2017113
- PAR ID:
- 10645526
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Environmental Research: Climate
- Volume:
- 4
- Issue:
- 4
- ISSN:
- 2752-5295
- Format(s):
- Medium: X Size: Article No. 045013
- Size(s):
- Article No. 045013
- Sponsoring Org:
- National Science Foundation
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