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Sea-Level Rise Due to Climate Change
Published in Saeid Eslamian, Faezeh Eslamian, Flood Handbook, 2022
The factors responsible for warming or cooling the atmosphere are known as climate forcing agents. GHGs are climate forcing agents because they can change the Earth's energy balance. The GHGs differ in their forcing power, e.g., a CH4 molecule has about 25 times the warming capacity of a CO2 molecule. The CO2 has a larger warming effect than CH4 because the CO2 is more abundant and stays in the atmosphere for a longer time. Some climate forcing agents work towards cooling, offsetting some of the heating effects of GHGs. Aerosols like tiny liquid or solid particles suspended in air and most of the visible air pollutants have a cooling effect because they scatter a portion of incoming sun rays back into space. Human activities like the burning of fossil fuels have increased the concentration of aerosols, especially over and around the major cities and industries. Change in land use and land cover also influence Earth's climate. Deforestation is responsible for 10–20% of the excess CO2 injected into the atmosphere every year. Agriculture adds N2O and CH4 into the atmosphere.
Atmospheric Pollution and Pollutants
Published in Wayne T. Davis, Joshua S. Fu, Thad Godish, Air Quality, 2021
Wayne T. Davis, Joshua S. Fu, Thad Godish
Because of effects on human health, the atmosphere, vegetation, and materials, pollutant gases and particles have received considerable research and regulatory attention. Although the terms gases and particles are used, pollutants exist in all three phases of matter. Particles include both solid and liquid substances. When dispersed in the atmosphere, solid and liquid particles form aerosols. Aerosols may reduce visibility, soil materials, and affect human health.
Environmental Engineering
Published in P.K. Jayasree, K Balan, V Rani, Practical Civil Engineering, 2021
P.K. Jayasree, K Balan, V Rani
Air pollutants consist of greenhouse gases. Carbon dioxide is one among such gases which is a component of exhaust from trucks and cars. Greenhouse gases lead to global warming by trapping heat from the Sun in the Earth’s atmosphere. Greenhouse gases naturally occur in Earth’s atmosphere is essential for the survival of the ecosystem, but the increase in greenhouses gases is the cause of most of the global warming. This increase occurs from car exhaust and pollutants released from smokestacks at factories and power plants. The trucks, smokestacks, and cars also release tiny particles, called aerosols, into the atmosphere. Dust lifted into the atmosphere from evaporating droplets, from deserts, from the ocean, released by the smoke from forest fires, and erupting volcanoes also causes the formation of aerosols. Air pollutants released by humans by burning of fossil fuels again add them to the atmosphere. Generally, in the last 150 years or so, the amount of CO2 in atmosphere has increased. While different types of aerosols act differently in the atmosphere, the overall effect of aerosols is cooling.
Adaptive step-size forward advection method for aerosol process simulation
Published in International Journal of Digital Earth, 2023
Yuang Wu, Shuo Liu, Bowen Shu, Weichao Sun, Sheng Wang, Hongyang Zhang, Chenchen Chen
An aerosol is a gaseous dispersion system composed of solid or liquid particles suspended in a gaseous medium. Outdoor aerosols are composed of complex sources, including combustion final products, pollens, droplet viruses, and harmful gases, which have potential harmful effects on human health. In recent years, inhalable particulate matter has been shown to be one of the major causes of increased human mortality (Chen 2012). For example, aerosols are carriers of burning smoke and kill 339,000 people annually (Wildhaber 2006). Aerosols are also an important means of transmission of epidemic viruses (Moreno and Gibbons 2022) and have played an important role in the novel coronavirus pandemic worldwide (Li and Tang 2022; Zhao et al. 2022). The flow of aerosols is influenced by complex conditions, including weather (Ma et al. 2017; Weng et al. 2014), such as temperature, humidity, wind speed, and pressure, and geographical factors, such as altitude and topographic factors (Reisen et al. 2015). Aerosol-related disasters involve complex geographical processes. Obtaining good results is difficult if they are analysed solely by spatial analysis, such as the study of polluted areas using the Gaussian diffusion model. Therefore, the study of the aerosol transport model is necessary for the simulation of many natural disasters.
Application of MELCOR for Simulating Molten Salt Reactor Accident Source Terms
Published in Nuclear Science and Engineering, 2023
Fred Gelbard, Bradley A. Beeny, Larry L. Humphries, Kenneth C. Wagner, Lucas I. Albright, Max Poschmann, Markus H. A. Piro
The next GRTR submodel calculation step, which is shown in the third and fourth rows in Fig. 1, is to determine the transport among the five forms, and releases to the cell atmosphere, respectively. In this step, there are three transport processes within the forms. Insoluble fission products may transport between the interface layer and the pool. The second process is transport from suspended insoluble fission products to deposit on heat structures in contact with the salt. The third process is transport of insoluble material between the pool and deposits on surfaces in the core. Aerosols may be formed from the condensation or nucleation of volatile species that are released to the gas space. However, since this process occurs in the atmosphere above the pool, it is therefore modeled with MELCOR’s existing radionuclide vapor and aerosol model. The state of the pool, deposited mass on surfaces, and released masses are passed back to MELCOR for transport within a facility. The equations describing the transport between forms and to the atmosphere above the pool are given later in this work. The three gas space releases given in highlighted boxes in the bottom row are (1) volatile vapor, (2) aerosol particles from the interface layer at the top of the salt pool, and (3) gases such as Xe and Kr. The direct release of aerosol from the top of the salt pool to the vapor space is discussed later in much detail.
Performance evaluation of multiple particulate matter monitoring instruments under higher temperatures and relative humidity in Southeast Asia and design of an affordable monitoring instrument (ManPMS)
Published in Instrumentation Science & Technology, 2023
Nam Duong Thanh, Hoa Tran Thi, Trung Nguyen Quang, Huy Nguyen Van, Giang Hoang Nguyen, Quyet Nguyen Huu, Tung Tran Son
The air quality in rural areas in the region has been negatively impacted as well. The open burning of agricultural waste and deforestation has been increasing to keep up with the demand for food and export.[15] The smoke from the activity has been recorded to travel across boundaries and oceans to affect adjacent countries. Haze is an atmospheric phenomenon in which visibility is degraded by aerosols. Air quality monitoring stations in Hat Yai (Thailand) detected open burning smoke originating from Indonesia during haze events.[16] Because of the constant burning, combined with the metrological conditions in the regions, the intensity and frequency of haze events would only worsen in the near future.[17]