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Introduction to Issue: Weather and climate are major factors in many aspects of our lives. It is vital in determining the best agricultural practices and which crops to plant. Many places on earth have a climate which presents unique challenges, like extreme heat or cold, powerful storms, or flooding. Rough weather is a major cause of transportation delays or accidents. An understanding of weather was, is and will be important for survival of our species. This is why we have to ask “Should sustainability of our technologies and societal structures be considered as an emerging factor to combat climate and weather phenomena”? Our position is yes and we have to be proactive in our solutions to climatic challenges. In our presentation we will cover aspects in this broad field. We will provide several study-cases for the climate-driven design principles of save and sustainable civil infrastructure, advances in controlling the effects of carbon dioxide emissions, and establishing weather-independent food security in zones of risky agriculture.Civil Infrastructure: Introduction: The vulnerability of our infrastructure has been widely expressed through its repeated failure to withstand weather phenomenon. For example, during the 2017 hurricane season in the U.S, there was an estimated damage of $125 billion (NOAA, 2017). The use of conventional materials such as concrete and metals alloys have proven ineffective in light of these accidents, which brings the question: what are some possible alternatives and what issues does sustainability pose when selecting various materials when considering infrastructure?Safety and Security:Most man-made structures rely heavily on the components of reinforced concrete (RC); unfortunately, under stress from forces such as seismic activities, RC often suffers from breakages caused by compression of the concrete as well as deformations of the reinforcing steel bars. These contributing factors all result in a relatively unsafe lifestyle along earthquake-prone areas, easily solved by using other materials such as Shape Memory Alloys. SMAs are well regarded for their superelasticity as well as thermomechanical abilities, both of which contribute to SMA’s high resistivity to deformations caused by either physical bending or heat.  Shape memory alloys, SMAs, consist of a cubic martensite  structure that upon being heated, transforms to the austenite phase. The austenite phase consists of heating steel, iron-based metal or iron so that it changes crystalline structure. The martensite phase consists of a crystal structure being created by diffusionless transformation (A diffusionless transformation is a phase change that occurs without the long-range diffusion of atoms but rather by some form of cooperative, homogeneous movement of many atoms that results in a change in crystalline structure. (Easterling and Porter, 1992). The change is dependent upon heat which is why most SMAs rely on heat to phase into their original shape. It would not be able to go back to its original position if it is exposed to high strain. However, the heat causes the molecules in the SMA to form another allotrope which has a higher elasticity and is capable of returning to its original position. Such technology is very sustainable as it is more adaptable to harsh weather. (Khan, 1972; Abbaschain and Reed-Hill, 1991). Aged RC bridge columns have an inadequate flexibility to absorb earthquake impact which prompts restrained transverse motion. These major flaws and therefore critical mistakes can be corrected by enclosing the columns’ external plastic hinge areas. The external enclosements would serve to increase the ductility of concrete by reducing damage and providing a counteracting prestress pressure without the need for enlargement of the concrete. Other alternatives that could be utilized to strengthen the reinforced concrete include steel strands or FRP straps, but the applications were quite limited due to the use of extensive labor and time when attempting to apply sufficiently prestressing force internally.Ethics: When considering the sustainability of structural materials, four key factors must be considered: the production of the material, construction, life cycle, and demolition. When producing concrete, many components such as aggregates (rocks and sand), hydraulic cement and water can have a negative impact on the environment. When aggregates are mined, useless byproducts are often produced and end up in landfills. Additionally, the production of hydraulic cement produces notable amounts of CO2 and a surprisingly negligible impact on the environment when considering the polluted water as well as waste products. However, when looking at the production of SMAs, many other factors come into play as well including the preparation of epoxy resins, degassing of the resin matrix, training of SMA wires, embedding of SMA wires in mold, curing process, and the final stage of forming the SMA “dog-bone” composite specimen. The average lifespan of concrete is also relatively short but can be considerably improved with the introduction of SMA spirals that serve to increase flexural ductility and make structures more sustainable.Conclusion: The increased integration and use of the emerging SMA technology alongside the conventional construction materials such as RC can allow for the improvement of economic manners when considering the increased strength of civil infrastructure. The inefficient use of infrastructure can be linked to increased carbon emissions, which is our next topic.Carbon Dioxide Emissions:Introduction:Our usage of fossil fuels (hydrocarbons) such as coal as a source of energy has led to massive influxes of carbon dioxide into the atmosphere. In 2016 alone, 49.3 gigatons of carbon dioxide was released into the atmosphere, which by mass is greater than the entire human population of Earth (Peters et al., 2017). Humanity’s dependence on fossil fuels is unsustainable as they are a non-renewable resource, and the carbon dioxide emissions from fossil fuels have been linked to global climate change. In order to achieve better sustainability, chemical engineers are developing and implementing methods of capturing large volumes of carbon dioxide gas and storing it, in a process called carbon capture and storage.Carbon Capture and Storage:The term carbon capture and storage is really a general term, as there are many ways to achieve its end goal, that is to reduce carbon dioxide emission levels by permanently storing the compound. Specifically, there are two general methods, injection and mineralization (Eloneva and Levanen, 2017). Injection, also known as post combustion carbon capture, is the most developed method with commercial applications since 2000. The process involves separating carbon dioxide from flue gas, usually through absorbing it into a solvent and later separating and compressing it to be permanently stored in specific locations underground. An issue with this method is that carbon dioxide, like all gases, has low solubility in water. As such, this method only captures about 38% of total emissions (Eloneva and Levanen, 2017).Mineralization, on the other hand, is a process still in development which involves precipitating carbon dioxide into a stable mineral form. This is based on chemical reactions which occur in nature, known as chemical weathering, where carbonic acid in rainwater (from carbon dioxide reacting with water in the atmosphere) reacts with calcium and magnesium oxides to form respective carbonate compounds (Bhattacharyya et al., 2011). In a laboratory setting, one method involves reacting flue gas containing carbon dioxide with a magnesium hydroxide solution under conditions of 2000 kPa and 773K to produce magnesium carbonate, which precipitates out due to its low solubility in water. The precipitate is then collected and transported elsewhere to be stored (Eloneva and Levanen, 2017).Safety and Security: The effects of carbon dioxide emissions on safety mainly stem from the fact that it’s a greenhouse gas, meaning it traps long wave radiation on the Earth’s surface and is directly responsible for global warming. Eventually, this can cause glaciers to melt, which poses as a safety risk to cities such as Osaka, Japan, due to the rising ocean levels being able to flood low sea level locations (Kiefer et al., 2014). Another risk to safety is that there is evidence that global warming increases the spread of mosquitoes and ticks, parasites which can transmit deadly diseases such as malaria and Lyme disease (Kiefer et al., 2014). As for its effects on security, carbon dioxide can form carbonic acid in water, meaning the effects of carbon dioxide emissions on security includes ocean acidification. This severely damages the food chain with regards to marine shell-building organisms, which will eventually affect food security for coastal areas around the world. Ethics:Since most of the carbon imbalance in our atmosphere was caused by human activities, we must ask ourselves if it is worth sacrificing the environment and its sustainability for our own needs. Global warming and ocean acidification are relevant issues which can lead to the extinction of species – such as polar bears (Ursus maritimus) in the arctic, or the various species which inhabit coral reefs around the world. Given that there are already technologies capable of reducing carbon output into the atmosphere, such as the aforementioned methods of carbon capture and storage, the sustainability of communities and ecosystems around the world depend on our actions. Conclusion:Supporting the initial question, it is clear that sustainability is an emerging factor to combat climate phenomena, in this case climate change due to carbon dioxide emissions. However, there are also issues relating to weather we need to address simultaneously, such as combating the effects of droughts on food security. Drought and Food Security: “In order for our species to be sustainable we must have food security. This can be a problem as the rising global temperatures are predicted to cause drought in many agricultural areas. (Wilhite and Glantz, 1985; Wu et al., 2001; Quiring and Papakryiakou, 2003; Wilhite et al., 2007). Meteorological drought occurs due to a prolonged lack of precipitation which leads to a decrease of soil moisture. Hydrologic drought occurs when streamflow, lake, and/or groundwater levels are significantly lower than normal. (Rhee et al., 2015). It is not uncommon for unsustainable agricultural practices to decimate a region’s water supply. To address this issue, new genetic technologies are being developed.” One potential technique in response to drought is a form of genetic modification is RNA interference or simply RNAi (Liou, 2010). “RNA interference (RNAi) is a way to “silence” genes by preventing the formation of the proteins that they code for. A type of gene therapy, it takes advantage of an intermediate step between DNA and protein (Understanding RNAi, n.d.).” RNAi is a mechanism of silencing gene expression after the gene has been transcribed (Ryerson, 2007). This interference is due to the presence of antisense RNA, which is complementary to a specific mRNA (Ryerson, 2007). The relationship between the complementary strands allows the antisense RNA and the cellular mRNA to bind to each other (Ryerson, 2007). The current model of RNAi involves 2 main steps; first the creation of an RNA induced silencing complex and then the degradation of the cellular mRNA by the RNA induced silencing complex (Ryerson, 2007).. The first step;  creation of the RISC occurs when double stranded RNA is found in the cell, which is recognized by an endonuclease, dicer, which cuts it into sections of nearly 20 nucleotides in length (Ryerson, 2007). An antisense RNA may then associate with a protein complex to form the RISC (Ryerson, 2007). The newly formed silencing complex may now associate with the cellular mRNA complementary to the RNA fragment in the RIS(Ryerson, 2007). The mRNA is degraded, effectively eliminating the translation of the mRNA of that specific gene, interfering with the expression (Ryerson, 2007). It is likely that many features of crop plants can be improved by RNA silencing, (Liou, 2010). The availability of the complete DNA sequence of Arabidopsis and rice has allowed the identification of many potential targets of RNA silencing, (Liou, 2010). Silencing of these RNAs is predicted to, among other things, improve  crop yield and make crops more resistant to drought , (Liou, 2010). Global food demand is expected to double in the coming year. For example wheat yields growing on 1 percent annually, need to increase 2 percent annually to match the growing demand for food as weather phenomena such as drought and climate change continue to contribute to the challenge that is food security, (Hardcastle, 2013). Genetic Modification however has the potential to improve crop yields and resistance to these damaging weather phenomena, sustainably, (Hardcastle, 2013). There are two major points at which safety pertaining to the issue of food security and methods to combat it may be addressed. The first is the issue itself: If the challenges posed by the weather phenomena are not responded to, effectively or in a sustainable manner, access to sufficient, safe food to meet daily dietary needs is comprised, but may be alleviate with an appropriate and sustainable response such as genetic modification (Understanding RNAi, n.d.; Hardcastle, 2013). Secondly, an issue of safety resides within methods to combat the issue at hand. The methods proposed in earlier pertaining to genetic modification have yet to excite the experimental stage, making them as of now unpredictable as they must be subject to further testing, (Understanding RNAi, n.d.). However in the case of safety there are also many advantages in using this method to combat  natural occurrences giving rise to food security, (Genetically modified crops, n.d.; Liou, 2010). For example, it makes sustainable living a reality, this technology used in a responsible manner has the potential to help meet the world’s long-term food needs more sustainably, as they have many potential advantages in terms of raising agricultural productivity, (Genetically modified crops, n.d.).Conclusion: While there is still much to be learned about the biology of plant–environment interactions, the fundamental technologies of plant genetic improvement, including crop genetic engineering, are in place, and are expected to play crucial roles in meeting the chronic demands of global food security, (Rine, 2011). However, genetically improved seed is only part of the solution”, as sustainability must be at the forefront of genetic modification in agriculture to create a long lasting and effective response to the global food security crisis, as a result of threatening weather phenomena, (Rine, 2011). Slide Change: Conclusion to Issue:In conclusion we have presented several case studies of climate driven challenges; along with the ethics involved in the safety and security. These examples support our response to the question “Should sustainability be considered a major factor when combating climate and weather phenomenon?”. Our answer is definitive “Yes” and we, as a society, have to be proactive in adapting our infrastructure to major natural disasters by investing into the design of smart materials like shape memory alloys. We must control and prevent the drastic climate changes which are a considerable challenge for the foreseeable future through the development and introduction of new carbon capture and storage technologies, all the while ensuring the global security of our food sources by working tirelessly on climate adaptable sustainable agriculture.

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