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- ItemCost-effective mitigation of nitrogen pollution from global croplands(London [u.a.] : Nature Publ. Group, 2023) Gu, Baojing; Zhang, Xiuming; Lam, Shu Kee; Yu, Yingliang; van Grinsven, Hans J. M.; Zhang, Shaohui; Wang, Xiaoxi; Bodirsky, Benjamin Leon; Wang, Sitong; Duan, Jiakun; Ren, Chenchen; Bouwman, Lex; de Vries, Wim; Xu, Jianming; Sutton, Mark A.; Chen, DeliCropland is a main source of global nitrogen pollution1,2. Mitigating nitrogen pollution from global croplands is a grand challenge because of the nature of non-point-source pollution from millions of farms and the constraints to implementing pollution-reduction measures, such as lack of financial resources and limited nitrogen-management knowledge of farmers3. Here we synthesize 1,521 field observations worldwide and identify 11 key measures that can reduce nitrogen losses from croplands to air and water by 30–70%, while increasing crop yield and nitrogen use efficiency (NUE) by 10–30% and 10–80%, respectively. Overall, adoption of this package of measures on global croplands would allow the production of 17 ± 3 Tg (1012 g) more crop nitrogen (20% increase) with 22 ± 4 Tg less nitrogen fertilizer used (21% reduction) and 26 ± 5 Tg less nitrogen pollution (32% reduction) to the environment for the considered base year of 2015. These changes could gain a global societal benefit of 476 ± 123 billion US dollars (USD) for food supply, human health, ecosystems and climate, with net mitigation costs of only 19 ± 5 billion USD, of which 15 ± 4 billion USD fertilizer saving offsets 44% of the gross mitigation cost. To mitigate nitrogen pollution from croplands in the future, innovative policies such as a nitrogen credit system (NCS) could be implemented to select, incentivize and, where necessary, subsidize the adoption of these measures.
- ItemLess extreme and earlier outbursts of ice-dammed lakes since 1900(London [u.a.] : Nature Publ. Group, 2023) Veh, Georg; Lützow, Natalie; Tamm, Jenny; Luna, Lisa V.; Hugonnet, Romain; Vogel, Kristin; Geertsema, Marten; Clague, John J.; Korup, OliverEpisodic failures of ice-dammed lakes have produced some of the largest floods in history, with disastrous consequences for communities in high mountains1–7. Yet, estimating changes in the activity of ice-dam failures through time remains controversial because of inconsistent regional flood databases. Here, by collating 1,569 ice-dam failures in six major mountain regions, we systematically assess trends in peak discharge, volume, annual timing and source elevation between 1900 and 2021. We show that extreme peak flows and volumes (10 per cent highest) have declined by about an order of magnitude over this period in five of the six regions, whereas median flood discharges have fallen less or have remained unchanged. Ice-dam floods worldwide today originate at higher elevations and happen about six weeks earlier in the year than in 1900. Individual ice-dammed lakes with repeated outbursts show similar negative trends in magnitude and earlier occurrence, although with only moderate correlation to glacier thinning8. We anticipate that ice dams will continue to fail in the near future, even as glaciers thin and recede. Yet widespread deglaciation, projected for nearly all regions by the end of the twenty-first century9, may bring most outburst activity to a halt.
- ItemPublisher Correction: Cost-effective mitigation of nitrogen pollution from global croplands (Nature, (2023), 613, 7942, (77-84), 10.1038/s41586-022-05481-8)(London [u.a.] : Nature Publ. Group, 2023) Gu, Baojing; Zhang, Xiuming; Lam, Shu Kee; Yu, Yingliang; van Grinsven, Hans J. M.; Zhang, Shaohui; Wang, Xiaoxi; Bodirsky, Benjamin Leon; Wang, Sitong; Duan, Jiakun; Ren, Chenchen; Bouwman, Lex; de Vries, Wim; Xu, Jianming; Sutton, Mark A.; Chen, DeliCorrection to: Nature https://doi.org/10.1038/s41586-022-05481-8 Published online 4 January 2023
- ItemGlobal vegetation resilience linked to water availability and variability([London] : Nature Publishing Group UK, 2023) Smith, Taylor; Boers, NiklasQuantifying the resilience of vegetated ecosystems is key to constraining both present-day and future global impacts of anthropogenic climate change. Here we apply both empirical and theoretical resilience metrics to remotely-sensed vegetation data in order to examine the role of water availability and variability in controlling vegetation resilience at the global scale. We find a concise global relationship where vegetation resilience is greater in regions with higher water availability. We also reveal that resilience is lower in regions with more pronounced inter-annual precipitation variability, but find less concise relationships between vegetation resilience and intra-annual precipitation variability. Our results thus imply that the resilience of vegetation responds differently to water deficits at varying time scales. In view of projected increases in precipitation variability, our findings highlight the risk of ecosystem degradation under ongoing climate change.
- ItemBetter insurance could effectively mitigate the increase in economic growth losses from U.S. hurricanes under global warming(Washington, DC [u.a.] : Assoc., 2023) Otto, Christian; Kuhla, Kilian; Geiger, Tobias; Schewe, Jacob; Frieler, KatjaGlobal warming is likely to increase the proportion of intense hurricanes in the North Atlantic. Here, we analyze how this may affect economic growth. To this end, we introduce an event-based macroeconomic growth model that temporally resolves how growth depends on the heterogeneity of hurricane shocks. For the United States, we find that economic growth losses scale superlinearly with shock heterogeneity. We explain this by a disproportional increase of indirect losses with the magnitude of direct damage, which can lead to an incomplete recovery of the economy between consecutive intense landfall events. On the basis of two different methods to estimate the future frequency increase of intense hurricanes, we project annual growth losses to increase between 10 and 146% in a 2°C world compared to the period 1980–2014. Our modeling suggests that higher insurance coverage can compensate for this climate change–induced increase in growth losses.
- ItemTime-scale synchronisation of oscillatory responses can lead to non-monotonous R-tipping([London] : Macmillan Publishers Limited, part of Springer Nature, 2023) Swierczek-Jereczek, Jan; Robinson, Alexander; Blasco, Javier; Alvarez-Solas, Jorge; Montoya, MarisaRate-induced tipping (R-tipping) describes the fact that, for multistable dynamic systems, an abrupt transition can take place not only because of the forcing magnitude, but also because of the forcing rate. In the present work, we demonstrate through the case study of a piecewise-linear oscillator (PLO), that increasing the rate of forcing can make the system tip in some cases but might also prevent it from tipping in others. This counterintuitive effect is further called non-monotonous R-tipping (NMRT) and has already been observed in recent studies. We show that, in the present case, the reason for NMRT is the peak synchronisation of oscillatory responses operating on different time scales. We further illustrate that NMRT can be observed even in the presence of additive white noise of intermediate amplitude. Finally, NMRT is also observed on a van-der-Pol oscillator with an unstable limit cycle, suggesting that this effect is not limited to systems with a discontinuous right-hand side such as the PLO. This insight might be highly valuable, as the current research on tipping elements is shifting from an equilibrium to a dynamic perspective while using models of increasing complexity, in which NMRT might be observed but hard to understand.