2020, Staal, Arie, Fetzer, Ingo, Wang-Erlandsson, Lan, Bosmans, Joyce H. C., Dekker, Stefan C., van Nes, Egbert H., Rockström, Johan, Tuinenburg, Obbe A.

Tropical forests modify the conditions they depend on through feedbacks at different spatial scales. These feedbacks shape the hysteresis (history-dependence) of tropical forests, thus controlling their resilience to deforestation and response to climate change. Here, we determine the emergent hysteresis from local-scale tipping points and regional-scale forest-rainfall feedbacks across the tropics under the recent climate and a severe climate-change scenario. By integrating remote sensing, a global hydrological model, and detailed atmospheric moisture tracking simulations, we find that forest-rainfall feedback expands the geographic range of possible forest distributions, especially in the Amazon. The Amazon forest could partially recover from complete deforestation, but may lose that resilience later this century. The Congo forest currently lacks resilience, but is predicted to gain it under climate change, whereas forests in Australasia are resilient under both current and future climates. Our results show how tropical forests shape their own distributions and create the climatic conditions that enable them.

2021, Rockström, Johan, Beringer, Tim, Hole, David, Griscom, Bronson, Mascia, Michael B., Folke, Carl, Creutzig, Felix

[no abstract available]

2013, Reusser, Dominik, Lissner, Tabea, Pradhan, Prajal, Holsten, Anne, Rybski, Diego, Kropp, Jürgen P.

We explore the link between improvements in human development and greenhouse gas emission. We argue that a disaggregated view on human development is required to understand the potential for decoupling of development from greenhouse gas emissions. To do so, we relate 16 elements from the livelihood index to emissions. Improvements in livelihood are decoupled from emissions for 10 elements, while only 6 are related to significant emissions. We operate the proposed framework for the example of food consumption and related emissions and find a reduction potential of about 13% compared to the total emissions from this sector.

2020, Vicedo-Cabrera, Ana M., Sera, Francesco, Liu, Cong, Armstrong, Ben, Milojevic, Ai, Guo, Yuming, Tong, Shilu, Lavigne, Eric, Kyselý, Jan, Urban, Aleš, Orru, Hans, Indermitte, Ene, Pascal, Mathilde, Huber, Veronika, Schneider, Alexandra, Katsouyanni, Klea, Samoli, Evangelia, Stafoggia, Massimo, Scortichini, Matteo, Hashizume, Masahiro, Honda, Yasushi, Ng, Chris Fook Sheng, Hurtado-Diaz, Magali, Cruz, Julio, Silva, Susana, Madureira, Joana, Scovronick, Noah, Garland, Rebecca M., Kim, Ho, Tobias, Aurelio, Íñiguez, Carmen, Forsberg, Bertil, Åström, Christofer, Ragettli, Martina S., Röösli, Martin, Guo, Yue-Liang Leon, Chen, Bing-Yu, Zanobetti, Antonella, Schwartz, Joel, Bell, Michelle L., Kan, Haidong, Gasparrini, Antonio

Objective To assess short term mortality risks and excess mortality associated with exposure to ozone in several cities worldwide. Design Two stage time series analysis. Setting 406 cities in 20 countries, with overlapping periods between 1985 and 2015, collected from the database of Multi-City Multi-Country Collaborative Research Network. Population Deaths for all causes or for external causes only registered in each city within the study period. Main outcome measures Daily total mortality (all or non-external causes only). Results A total of 45 165 171 deaths were analysed in the 406 cities. On average, a 10 μg/m 3 increase in ozone during the current and previous day was associated with an overall relative risk of mortality of 1.0018 (95% confidence interval 1.0012 to 1.0024). Some heterogeneity was found across countries, with estimates ranging from greater than 1.0020 in the United Kingdom, South Africa, Estonia, and Canada to less than 1.0008 in Mexico and Spain. Short term excess mortality in association with exposure to ozone higher than maximum background levels (70 μg/m 3) was 0.26% (95% confidence interval 0.24% to 0.28%), corresponding to 8203 annual excess deaths (95% confidence interval 3525 to 12 840) across the 406 cities studied. The excess remained at 0.20% (0.18% to 0.22%) when restricting to days above the WHO guideline (100 μg/m 3), corresponding to 6262 annual excess deaths (1413 to 11 065). Above more lenient thresholds for air quality standards in Europe, America, and China, excess mortality was 0.14%, 0.09%, and 0.05%, respectively. Conclusions Results suggest that ozone related mortality could be potentially reduced under stricter air quality standards. These findings have relevance for the implementation of efficient clean air interventions and mitigation strategies designed within national and international climate policies. © Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to.

2020-06-13, Worthington, Simon

X-Sprint: Climate and migration - Workshop - Infrastructure for the Year to come Summer School 2020 #OCK @OCKProject - 10 June 2020. From the Open Climate Knowledge project. https://github.com/OCKProject

2015, Hanf, Stefan, Fischer, Sarah, Hartmann, Henrik, Keiner, Robert, Trumbore, Susan, Popp, Jürgen, Frosch, Torsten

Photosynthesis and respiration are major components of the plant carbon balance. During stress, like drought, carbohydrate supply from photosynthesis is reduced and the Krebs cycle respiration must be fueled with other stored carbon compounds. However, the dynamics of storage use are still unknown. The respiratory quotient (RQ, CO2 released per O2 consumed during respiration) is an excellent indicator of the nature of the respiration substrate. In plant science, however, online RQ measurements have been challenging or even impossible so far due to very small gas exchange fluxes during respiration. Here we apply cavity-enhanced multi-gas Raman spectrometry (CERS) for online in situ RQ measurements in drought-tolerant pine (Pinus sylvestris [L.]) and drought-intolerant spruce (Picea abies [L. H. Karst]). Two different treatments, drought and shading, were applied to reduce photosynthesis and force dependency on stored substrates. Changes in respiration rates and RQ values were continuously monitored over periods of several days with low levels of variance. The results show that both species switched from COH-dominated respiration (RQ = 1.0) to a mixture of substrates during shading (RQ = 0.77–0.81), while during drought only pine did so (RQ = 0.75). The gas phase measurements were complemented by concentration measurements of non-structural carbohydrates and lipids. These first results suggest a physiological explanation for greater drought tolerance in pine. CERS was proven as powerful technique for non-consumptive and precise real-time monitoring of respiration rates and respirational quotients for the investigation of plant metabolism under drought stress conditions that are predicted to increase with future climate change.