Reactive species from aviation in the multi-scale climate-chemistry model system MECO(n)

<p>Aviation aims to reduce its climate impact by identifying promising mitigation options which are able to reduce the overall climate effects of aviation considering CO<sub>2</sub> and non-CO<sub>2</sub> effects. While aiming to identify fuel optimal trajectories, aviation also aims to reduce the non-CO<sub>2</sub> effects comprising NO<sub>x</sub>-induced changes of atmospheric ozone and methane. Here climate-chemistry models are required which are able to quantify perturbations in atmospheric composition of reactive species (NO<sub>x</sub>, O<sub>3</sub>) and the associated radiative forcings of aviation emissions relying on advanced modelling capabilities, realistic emission inventory data and global-scale observational datasets from research infrastructures like IAGOS and DLR aircraft measurement campaign data.</p> <p>We use the multi-scale climate-chemistry MECO(n) system which is a “MESSy-fied ECHAM and COSMO nested n-times”, relying on the Modular Earth Submodel System (MESSy) framework. For this purpose, both models have been equipped with the MESSy infrastructure, implying that the same process formulations (MESSy submodels) are available for both models. Modelled atmospheric distributions are systematically compared to observational data from aircraft measurements in the upper troposphere and lower stratosphere. Nudging of meteorology to ERA5 interim data, and special diagnostics available within the modular MESSy infrastructure are implemented in the numerical simulations. Online sampling along aircraft trajectories allows to extract model data with a high temporal resolution (MESSy submodel S4D), in order to evaluate model representation and key processes.</p> <p>Beyond systematic evaluation with IAGOS scheduled aircraft measurements, episodes will be evaluated where dedicated measurements from aircraft campaigns are available, comprising Spring 2014 (ML-CIRRUS campaign), early summer 2020 (Blue Sky campaign) and summer 2021 (Cirrus-HL campaign). Our analysis of reactive species, NO<sub>y</sub> and ozone, identifies those weather pattern and synoptic situations where aviation contributes strong signals, resulting in recommendations on measurement strategies to detect aviation signal in the atmosphere. We evaluate model representation of the NO<sub>x</sub>-induces effect on radiatively active species ozone and methane in both model instances, ECHAM5 and COSMO. This is key for advancing the scientific understanding of NO<sub>x</sub>-induced effects from aviation which is required in order to quantify potential compensation and trade-offs when identifying robust mitigation options for sustainable aviation.</p> <p>This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 875036 (ACACIA, Advancing the Science for Aviation and Climate) and has been supported by the DLR-Projekt Eco2Fly. This work uses measurement data from the European Research Infrastructure IAGOS/CARIBIC. High-Performance Super Computing simulations have been performed by the Deutsches Klima-Rechenzentrum (DKRZ, Hamburg) and the Leibniz-Rechenzentrum (LRZ, München).</p>

Countries’ Progress and Enablers for Circular Carbon Economies

The circular carbon economy (CCE) is a new concept, developed in detail by Saudi scholars and stakeholders since 2019 and promoted via Saudi Arabia’s Group of Twenty (G20) presidency in 2020. The CCE is conceptualized as an economy in which atmospheric carbon dioxide emissions are minimized and offset by reducing, recycling, reusing, and removing carbon. The concept emphasizes the need to address emissions holistically using all available mitigation options. It also recognizes the economic value of carbon and each country’s specific circumstances.

Community knowledge and awareness of aflatoxin in dietary staples in rural Busia county, Kenya: A mixed methods study

Aflatoxins are an important food safety challenge globally and in Kenya. Understanding a community’s knowledge, perception and practices is instrumental to improvement of aflatoxin control measures. Creating awareness on the causes of contamination and mitigation options could improve aflatoxin mitigation. This study aimed to map out dietary staples, establish drivers of food choices, describe knowledge and perceptions on aflatoxin and post-harvest grain management practices and use among the communities in Busia County in order to guide future evidence-based aflatoxin prevention and public health interventions. A household survey was conducted in 40 villages, and participants were selected using stratified systematic sampling in three sub-counties in rural Busia County. The survey was complemented and triangulated with a qualitative study component. Focus Group Discussions with sixty women and sixteen semi- structured interviews with nine men and seven women were conducted. Both descriptive and statistical analysis of data were performed. The results showed variability in household diversity scores and maize was observed as the community staple. While both younger and older participants were able to identify spoilt grains, they demonstrated limited knowledge and awareness of aflatoxin. Participants were not aware that seemingly clean grains could be colonized by aflatoxin as they only associated spoilage with discoloration and bitter taste of flour. Study participants were also not aware of the aflatoxin pathways to exposure as they used the spoilt grains in feeding chicken, making animal feed and local brew. Appropriate disposal methods of aflatoxin contaminated food were not known. The knowledge gap was attributed to lack of awareness creation and sensitization by the relevant government ministries. For effective control and prevention of aflatoxin contamination, farmers and traders need to be aware of the causes of aflatoxin contamination of grains, available mitigation options and health risks attributable to aflatoxin exposure in order to self-regulate. Ministries of health and agriculture, through their public health officers, community health workers and agricultural extension officers respectively need to collaborate and spearhead awareness creation among communities and institute food surveillance systems in Busia County.

Ethics of selective restriction of liberty in a pandemic

Liberty-restricting measures have been implemented for centuries to limit the spread of infectious diseases. This article considers if and when it may be ethically acceptable to impose selective liberty-restricting measures in order to reduce the negative impacts of a pandemic by preventing particularly vulnerable groups of the community from contracting the disease. We argue that the commonly accepted explanation—that liberty restrictions may be justified to prevent harm to others when this is the least restrictive option—fails to adequately accommodate the complexity of the issue or the difficult choices that must be made, as illustrated by the COVID-19 pandemic. We introduce a dualist consequentialist approach, weighing utility at both a population and individual level, which may provide a better framework for considering the justification for liberty restrictions. While liberty-restricting measures may be justified on the basis of significant benefits to the population and small costs for overall utility to individuals, the question of whether it is acceptable to discriminate should be considered separately. This is because the consequentialist approach does not adequately account for the value of equality. This value may be protected through the application of an additional proportionality test. An algorithm for making decisions is proposed. Ultimately whether selective liberty-restricting measures are imposed will depend on a range of factors, including how widespread infection is in the community, the level of risk and harm a society is willing to accept, and the efficacy and cost of other mitigation options.

Fungal Diversity and Aflatoxins in Cereals and Cassava-Based Foods From Ondo State, Nigeria

Cereals and cassava-based foods serve as major dietary sources for several households in Nigeria. However, these foods are highly prone to contamination by moulds and aflatoxins owing to poor storage and vending practices. We therefore studied the fungal diversity of maize, cassava-based flour (pupuru) and rice vended in markets from Ondo state, Nigeria, and assessed the aflatoxin levels of these using Enzyme-Linked Immunosorbent Assay. Fungi were detected in 93 (88 %) of the 106 food samples. Molecular analysis of 65 representative isolates revealed 26 species belonging to 5 genera: Aspergillus (80.9 %), Penicillium (15.4 %) and Talaromyces (1.9 %) in the Ascomycota; Syncephalastrum (1.2 %) and Lichtheimia (0.6%) in Mucoromycota. Aspergillus flavus was the predominant species in the food samples. Aflatoxins were found in 98 % of the 42 representative food samples and about one half (49.8 %) exceeded the 10 μg/kg threshold adopted in Nigeria for total aflatoxins. Integrated mitigation options, including at post-harvest stages, are suggested to ensure consumer safety.

Mitigation options to reduce peak air temperature and air-conditioning demand in the context of a warming climate for a tropical coastal city

The International Energy Agency (IEA) predicts the cooling requirement for buildings globally increases by three-fold by 2050 without additional policy interventions. The impacts of these increases for energy demand for human comfort are more pronounced in the Caribbean, where building energy demands often exceed 50% of the total electricity. This study presents mid-of century and end of century cooling demand projections along with demand alleviation measures for San Juan Metropolitan Area of the Caribbean Island of Puerto Rico using a high-resolution configuration of the Weather Research and Forecasting (WRF) model coupled with Building Energy Model (BEM) forced by bias-corrected Community Earth Systems Model (CESM1) global simulations. The World Urban Database Access Portal Tool (WUDAPT) Land Class Zones (LCZ) is used for urban classes and the MODIS land covers land use is depicted for all-natural classes. Energy mitigation options explored include the integration of solar power in buildings, the use of white roofs, and high-efficiency HVAC systems. The impact of climate change is simulated to increase minimum temperatures at the same rate as maximum temperatures. However, the maximum temperatures are projected to rise by 1-1.5C and 2C for mid and end-of-century, respectively, increasing peak AC demand by 12.5% and 25%, correspondingly. However, the explored mitigation options surpass both increases in temperature and AC demand. The AC demand reduction potential with energy mitigation options for 2050 and 2100 decreases the need by 13% and 1.5% with the historical periods.