| 1. |
- Krishnamohan, K. S., et al.
(författare)
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Effects of local and remote black carbon aerosols on summer monsoon precipitation over India
- 2021
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Ingår i: Environmental Research Communications (ERC). - : IOP Publishing. - 2515-7620. ; 3:8
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we perform idealized climate model simulations to assess the relative impacts of an increase in local black carbon (BC) aerosols (located over the Indian region) and the remote BC aerosols (located outside the Indian region) on the summer monsoon precipitation over India. We decompose the precipitation changes into fast adjustments triggered by the introduction of the forcing agent and slow response that is associated with the global mean temperature change. We find that a 60-fold increase in the 'present-day' global distribution of BC aerosols leads to an increase in precipitation over India, which is mainly contributed by an increase in remote BC aerosols. When remote BC aerosols are increased, the fast adjustments contribute to an increase in precipitation in association with the warming of the northern hemisphere land and the related northward Intertropical Convergence Zone (ITCZ) shift. For an increase in local aerosols too, by enhancing the upper tropospheric temperature meridional gradient in the Indian region, the fast adjustments contribute to an increase in precipitation over India. The slow response contributions in both cases are related to the regional patterns of SST change and the resulting changes to meridional temperature gradient in the Indian region and zonal circulation changes. The net precipitation change over India is an increase (decrease) for an increase in remote (local) BC aerosols. As the interpretation of our results relies on ITCZ shift related to planetary energetics, differing land-ocean response and meridional temperature gradients in the Indian region, the results from our study are likely to be robust across climate models.
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| 2. |
- Richardson, Katherine, et al.
(författare)
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Earth beyond six of nine planetary boundaries
- 2023
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Ingår i: Science Advances. - 2375-2548. ; 9:37
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Tidskriftsartikel (refereegranskat)abstract
- This planetary boundaries framework update finds that six of the nine boundaries are transgressed, suggesting that Earth is now well outside of the safe operating space for humanity. Ocean acidification is close to being breached, while aerosol loading regionally exceeds the boundary. Stratospheric ozone levels have slightly recovered. The transgression level has increased for all boundaries earlier identified as overstepped. As primary production drives Earth system biosphere functions, human appropriation of net primary production is proposed as a control variable for functional biosphere integrity. This boundary is also transgressed. Earth system modeling of different levels of the transgression of the climate and land system change boundaries illustrates that these anthropogenic impacts on Earth system must be considered in a systemic context.
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| 3. |
- Rockström, Johan, et al.
(författare)
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Identifying a Safe and Just Corridor for People and the Planet
- 2021
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Ingår i: Earth's Future. - 2328-4277. ; 9:4
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Tidskriftsartikel (refereegranskat)abstract
- Keeping the Earth system in a stable and resilient state, to safeguard Earth's life support systems while ensuring that Earth's benefits, risks, and related responsibilities are equitably shared, constitutes the grand challenge for human development in the Anthropocene. Here, we describe a framework that the recently formed Earth Commission will use to define and quantify target ranges for a safe and just corridor that meets these goals. Although safe and just Earth system targets are interrelated, we see safe as primarily referring to a stable Earth system and just targets as being associated with meeting human needs and reducing exposure to risks. To align safe and just dimensions, we propose to address the equity dimensions of each safe target for Earth system regulating systems and processes. The more stringent of the safe or just target ranges then defines the corridor. Identifying levers of social transformation aimed at meeting the safe and just targets and challenges associated with translating the corridor to actors at multiple scales present scope for future work.
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