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Project: GCOS Earth Heat Inventory - A study under the Global Climate Observing System (GCOS) concerted international effort to update the Earth heat inventory (EHI), and presents an updated international assessment of ocean warming estimates, and new and updated estimates of heat gain in the atmosphere, cryosphere and land over the period from 1960 to present. Summary: The file “GCOS_EHI_1960-2020_Earth_Heat_Inventory_Ocean_Heat_Content_data.nc” contains a consistent long-term Earth system heat inventory over the period 1960-2020. Human-induced atmospheric composition changes cause a radiative imbalance at the top-of-atmosphere which is driving global warming. Understanding the heat gain of the Earth system from this accumulated heat – and particularly how much and where the heat is distributed in the Earth system - is fundamental to understanding how this affects warming oceans, atmosphere and land, rising temperatures and sea level, and loss of grounded and floating ice, which are fundamental concerns for society. This dataset is based on a study under the Global Climate Observing System (GCOS) concerted international effort to update the Earth heat inventory published in von Schuckmann et al. (2020), and presents an updated international assessment of ocean warming estimates, and new and updated estimates of heat gain in the atmosphere, cryosphere and land over the period 1960-2020. The dataset also contains estimates for global ocean heat content over 1960-2020 for different depth layers, i.e., 0-300m, 0-700m, 700-2000m, 0-2000m, 2000-bottom, which are described in von Schuckmann et al. (2022). This version includes an update of heat storage of global ocean heat content, where one additional product (Li et al., 2022) had been included to the initial estimate. The Earth heat inventory had been updated accordingly, considering also the update for continental heat content (Cuesta-Valero et al., 2023).

This data package contains data used for an model-data intercomparison originally published in: D. K. Hutchinson, H. K. Coxall, D. J. Lunt, M. Steinthorsdottir, A. M. de Boer, M. Baatsen, A. von der Heydt, M. Huber, A. T. Kennedy-Asser, L. Kunzmann, J.-B. Ladant, C. H. Lear, K. Moraweck, P. N. Pearson, E. Piga, M. J. Pound, U. Salzmann, H. D. Scher, W. P. Sijp, K. K. Śliwińska, P. A. Wilson, and Z. Zhang, 2021: The Eocene-Oligocene transition: a review of marine and terrestrial proxy data, models and model-data comparisons, Climate of the Past, 17, 269-315. https://doi.org/10.5194/cp-17-269-2021 These data are also used in a further model-data intercomparison of Antarctic temperatures: Emily Tibbett, Natalie J Burls, David K. Hutchinson, Sarah J Feakins, (2023), Proxy-Model Comparison for the Eocene-Oligocene Transition in Southern High Latitudes, Paleoceanography and Paleocliamtology, In Review. Pre-print avaiable from: https://www.authorea.com/doi/full/10.1002/essoar.10511735.2 The package contains surface air temperature and sea surface temperature from an ensemble of model simulations of the Eocene-Oligocene transition. These data are provided at annual and monthly frequency. They are also provided on the original model grid, and an interpolated common grid used for the intercomparison. (The common grid is based on the HadCM3BL model grid.) All data are provided in NETCDF format with self-describing variable names. The name and explanation of the interpolated data files are contained in: table_of_experiments.xlsx Please read that spreadsheet to interpret the filenames, and see Table 2 (p291) of Hutchinson et al (2021) for experiment descriptions. Please also be mindful to cite the original authors of the simulations when using these data, whose work made this dataset possible. The appropriate citations are listed below: Reference DOI link Baatsen et al (2020) https://doi.org/10.5194/cp-16-2573-2020 Goldner et al (2014) https://doi.org/10.1038/nature13597 Ladant et al (2014a,b) https://doi.org/10.5194/cp-10-1957-2014 https://doi.org/10.1002/2013PA002593 Hutchinson et al (2018, 2019) https://doi.org/10.5194/cp-14-789-2018 https://doi.org/10.1038/s41467-019-11828-z Kennedy et al (2015) https://doi.org/10.1098/rsta.2014.0419 Zhang et al (2012, 2014) https://doi.org/10.5194/gmd-5-523-2012 https://doi.org/10.1038/nature13705 Sijp et al (2009) https://doi.org/10.1175/2009JCLI3003.1

Biodiesel production processes using coconut oil containing a relatively high content of free fatty acids (4.5% w/v and higher) have been characterized using alkali, acid and enzymatic- based catalysts. The use of ethanol (molar ratio of 3:1 of ethanol:triglycerides) instead of methanol was evaluated in all processes. An alkali-based process resulted in rapid conversion of the triglycerides in the coconut oil to esters with an 80% conversion in 5-10 min. However pre-treatment with 0.7% H2SO4 v/v at 50oC for 3 h was required before alkali addition to avoid saponification of the free fatty acids. By comparison, a longer reaction time (50 h) was required for the acid process which also resulted in a lower conversion (67% at 50oC). The use of an acid overcomes the limitations of the alkali process of saponification when high FFA content oils are used, and gave a higher conversion 70% at 75oC after 300 min. By comparison use of an enzymatic (lipase) catalyst (1% w/v) at 50oC resulted in a conversion of 80% in 50 h. The enzyme based process under similar conditions was significantly improved by the use of high frequency sonication which reduced the reaction time to 3 h and achieved a 92% conversion of triglycerides to esters. To further improve the economics of the enzyme process, an initial study showed that the enzyme catalyst was able to be recycled with only a 20% decrease in conversion. The use of the glycerol by-product from the enzyme process as a carbon source for yeast growth resulted in improved kinetics to that for yeast growth on pure glycerol indicating that no inhibitory by-products were produced during the enzyme process. The overall economics of the process, and its sensitivity to key process variables was further analysed using a computer-based model of biodiesel production. It showed that an internal rate of return (IRR) of 30% for a commercial size plant of 4 million litre per annual.

AbstractChina is under pressure to improve its agricultural productivity to keep up with the demands of a growing population with increasingly resource‐intensive diets. This productivity improvement must occur against a backdrop of carbon intensity reduction targets, and a highly fragmented, nutrient‐inefficient farming system. Moreover, the Chinese government increasingly recognizes the need to rationalize the management of the 800 million tonnes of agricultural crop straw that China produces each year, up to 40% of which is burned in‐field as a waste. Biochar produced from these residues and applied to land could contribute to China's agricultural productivity, resource use efficiency and carbon reduction goals. However competing uses for China's straw residues are rapidly emerging, particularly from bioenergy generation. Therefore it is important to understand the relative economic viability and carbon abatement potential of directing agricultural residues to biochar rather than bioenergy. Using cost‐benefit analysis (CBA) and life‐cycle analysis (LCA), this paper therefore compares the economic viability and carbon abatement potential of biochar production via pyrolysis, with that of bioenergy production via briquetting and gasification. Straw reincorporation and in‐field straw burning are used as baseline scenarios. We find that briquetting straw for heat energy is the most cost‐effective carbon abatement technology, requiring a subsidy of $7 MgCO2e−1 abated. However China's current bioelectricity subsidy scheme makes gasification (NPV $12.6 million) more financially attractive for investors than both briquetting (NPV $7.34 million), and pyrolysis ($−1.84 million). The direct carbon abatement potential of pyrolysis (1.06 MgCO2e per odt straw) is also lower than that of briquetting (1.35 MgCO2e per odt straw) and gasification (1.16 MgCO2e per odt straw). However indirect carbon abatement processes arising from biochar application could significantly improve the carbon abatement potential of the pyrolysis scenario. Likewise, increasing the agronomic value of biochar is essential for the pyrolysis scenario to compete as an economically viable, cost‐effective mitigation technology.

AbstractA better understanding of how climate affects growth in tree species is essential for improved predictions of forest dynamics under climate change. Long-term climate averages (mean climate) and short-term deviations from these averages (anomalies) both influence tree growth, but the rarity of long-term data integrating climatic gradients with tree censuses has so far limited our understanding of their respective role, especially in tropical systems. Here, we combined 49 years of growth data for 509 tree species across 23 tropical rainforest plots along a climatic gradient to examine how tree growth responds to both climate means and anomalies, and how species functional traits mediate these tree growth responses to climate. We showed that short-term, anomalous increases in atmospheric evaporative demand and solar radiation consistently reduced tree growth. Drier forests and fast-growing species were more sensitive to water stress anomalies. In addition, species traits related to water use and photosynthesis partly explained differences in growth sensitivity to both long-term and short-term climate variations. Our study demonstrates that both climate means and anomalies shape tree growth in tropical forests, and that species traits can be leveraged to understand these demographic responses to climate change, offering a promising way forward to forecast tropical forest dynamics under different climate trajectories.

Abstract: After the implementation of a biofuel target in 2017, China, the second largest consumer of oil in the world, accelerated the development of lignocellulosic biomass technology to produce ethanol and minimized food security risks commonly associated with first generation biofuel production. In this study, Life Cycle Assessment (LCA) is used to investigate three new lignocellulosic biomass refinery systems based on corncob which co-produce ethanol with chemicals and energy. The bioethanol is used in E10 and E85 biofuel mixes and these are compared with a fossil gasoline reference system. Using 1 km distance driven by a compact size flexible fuel passenger vehicle as the functional unit and a exergy allocation approach to the raw material inputs and to the co-products in the simulated multifunctional biorefinery processes, the results indicate that regardless of the configuration of the ethanol-biorefinery, ethanol-blended fuels performed better than gasoline in terms of fossil fuels depletion (E10 6% lower; E85 64–70% lower), global warming potential (E10 1–10% lower; E85 5–113% lower) and human toxicity potential (E10 6–7% lower; E85 72–75% lower), but worst in terms of ozone layer depletion (E10 4.5–6.8 times higher; E85 51.9–78.2 times higher), acidification (E10 30–50% higher; E85 3.3–5.5 times higher) and eutrophication potential (E10 5.2–7.0 times higher; E85 42.4–64.0 times higher) than gasoline.

While different in emphasis, spirituality and sustainable development are intertwined concepts that cannot be meaningfully discussed in isolation from each other. This is especially pertinent in Pacific Island countries that are characterised by both high degrees of vulnerability to climate change and high degrees of religious engagement. There is a paucity of research that examines the relationship between spirituality and sustainable development in contemporary human development discourse. To address this gap in the literature, this research employs an inductive and exploratory methodological approach to the study of major development organisations in Australia. It investigates what significance contemporary NGOs ascribe to matters of spirituality in the design and implementation of their community aid and development programming in the Pacific and beyond. To achieve its goal, the study conducts a systematic term frequency analysis in the annual reports of government-funded and independently funded NGOs, both faith-based and secular. It extends previous research by focusing expressly on the intersectionality of sustainable development and spirituality as a fertile space for interdisciplinary inquiry. The findings link development policy and practice more closely to the needs and worldviews of Pacific peoples. A better understanding of the spirituality–sustainability nexus will enable more effective, sustainable, equitable, ethical, and culturally acceptable development programming. Crucially, integrated approaches promise to make ongoing community development programmes and adaptation responses to climate-driven environmental change more effective and sustainable. Finally, it is an important aim of this study to conceptualise various opportunities for future research, thus laying the foundation for an important emergent research agenda.