China
Africa
Explore chapters and articles related to this topic
Impact of Business and Industry on the Environment
Published in Titus De Silva, Integrating Business Management Processes, 2020
The term “ozone hole” is loosely applied, and it refers to regions where the ozone concentration is less than 200 D.U. A normal level of ozone in the layer is about 300–350 D.U. During spring time in Antarctica, and to a lesser extent in the Artic, special meteorological conditions and very low temperatures accelerate and enhance ozone depletion by man-made ODS.
Ozone and Ozone Depletion
Published in Yeqiao Wang, Atmosphere and Climate, 2020
The second issue of atmospheric ozone on the environment relates to the depleted "good" ozone in the stratosphere. Ground-based and satellite instruments have measured decreases in the amount of ozone in the stratosphere since the 1980s [11]. The most extreme case occurs over some parts of Antarctica, where up to 60% of the total overhead amount of ozone disappeared during some periods of the Southern Hemisphere spring (August-October). Similar processes occur in the Arctic region that have also led to significant ozone depletion during late winter and spring in many recent years. It is found that the primary cause for the ozone depletion in the stratosphere is the presence of some ozone-depleting substances (ODSs) such as chlorine- and bromine-containing gases [12]. These gases can dissociate and release chlorine atoms in the presence of UV-B radiation, and chlorine atoms then go on to catalyze ozone destruction. In 1987, many countries have joined an effort to stop the ozone depletion in the stratosphere by signing an international agreement known as the "Montreal Protocol" [13]. In this agreement, governments have decided to develop more "ozone-friendly" substitutes and eventually discontinue those productions that emit ozone-depleting gases.
Ozone, Acid Rains, and Greenhouse Gases
Published in Jeff Kuo, Air Pollution Control Engineering for Environmental Engineers, 2018
However, scientific evidences have shown that the ozone shield has been depleted beyond the natural process since early 1970s. This beneficial ozone is being gradually destroyed by manmade chemicals. At locations where the protective ozone layer has been significantly depleted (e.g., North or South Pole), it is called a “hole” in the ozone layer and the problem is often referred to as ozone depletion. This allows more UV radiation to reach the Earth’s surface and leads to increased incidences of skin cancer, cataracts, and other health problems. Elevated levels of UV radiation can also cause detrimental ecological effects such as stressing productivity of marine phytoplankton, an essential component of the oceanic food web.
A review on the progress and development of thermoelectric air conditioning system
Published in International Journal of Green Energy, 2023
Manoj Sasidharan, Mohd Faizul Mohd Sabri, Sharifah Fatmadiana Wan Muhammad Hatta, Suriani Ibrahim
The growth of the air conditioning industry was expected to increase an industry-wide consumption rate of 70% by 1980. However, the usage of refrigerant was of great concern to the air conditioning industry. In 1989, the Montreal Protocol was introduced to protect the ozone layer as R12 had a higher ozone depleting potential (ODP). Therefore, the air conditioning industry switched the refrigerant from R12 to R134a due to global warming. At that time, R134a was the most prevalent refrigerant found in air conditioning systems. Then in 1997, the Kyoto protocol was introduced with the aim of controlling the usage of refrigerant R134a due to the higher Global Warming Potential (GWP) value. Later, the United Nations banned the use of current refrigerants that have a GWP value greater than 150. The Kyoto protocol has resulted in improving the current refrigerant (R134a) in the system while preventing leakage (Vaghela 2017; Vashisht and Rakshit 2021; Yoo and Lee 2009).
A comprehensive review on organic Rankine cycle systems used as waste heat recovery technologies for marine applications
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2022
Olgun Konur, C. Ozgur Colpan, Omur Y. Saatcioglu
The environmental effects of working fluids have been deeply discussed since the discovery of ozone depletion in the Antarctica region. The Montreal Protocol in 1987 was signed by 197 countries and considered the most successful global environmental action that restricted the use of ozone-depleting working fluids (EPA 2020). The concept of ozone depletion potential (ODP) has been proposed as a measure of destructive effects of a chemical in removing ozone relative to a similar mass of R-11 (also known as CFC-11 or Freon-11), regarding the ODP value of R-11 as 1.0 (Dincer 2018). In addition to ODP values, the working fluids are also defined by their global warming potential (GWP) values. GWP of gas stands for calculating the amount of energy emission that 1-ton of gas can carry on compared with the emissions of 1-ton of CO2 (Vallero 2019). The ODP and GWP values of working fluids used in ORC systems are important factors as selection criteria because as a normal operation, the working fluid leaks to the atmosphere in small proportions through piping, flanges, valves, and other components on the system design or during maintenance duties.
Sustainable plant-based bioactive materials for functional printed textiles
Published in The Journal of The Textile Institute, 2021
Alka Madhukar Thakker, Danmei Sun
We ought to mandatorily note that, due to ozone depletion UV rays are causing skin ailments such as allergies, aging, carcinogenesis, and erythema. The synthetic dyes are a threat to the atmosphere and anthropoid health. Surface modifications and textile finishes with synthetic chemicals and wet processing are found to be highly polluting and harmful to human health (Gorjanc et al., 2018). Therefore, the ultraviolet protective factor (UPF) of the fabric is calculated. Aracil et al., further explains, the UVRs’ are electromagnetic radiations up to 400 nm, they are divided into three as per their strength, UVA (315–400 nm), UVB (280–315 nm), and UVC (100–280 nm). UVC and UVB (90%) are absorbed by the ozone layer, water, carbon dioxide, and oxygen in the stratosphere. Therefore, UVB (10%) and UVA reaches the earth. Refer to Table 10 (Aracil et al., 2016). They pierce through the human skin and are proven to be detrimental. Ozone depletion has accelerated this process. Textile emission and effluents provide the momentum to ozone depletion. Therefore, it is essential to refute the dangers arising from the textile industry.