Search results
Results From The WOW.Com Content Network
Ozone can be destroyed by a number of free radical catalysts; the most important are the hydroxyl radical (OH·), nitric oxide radical (NO·), chlorine radical (Cl·) and bromine radical (Br·). The dot is a notation to indicate that each species has an unpaired electron and is thus extremely reactive.
Ozone (O3) is a trace gas which has been of concern because of its unique dual role in different layers of the lower atmosphere. [1] Apart from absorbing UV-B radiation and converting solar energy into heat in the stratosphere, ozone in the troposphere provides greenhouse effect and controls the oxidation capacity of the atmosphere. [1]
The ozone hole was much more seen as a "hot issue" and imminent risk compared to global climate change, [13] as lay people feared a depletion of the ozone layer (ozone shield) risked increasing severe consequences such as skin cancer, cataracts, [23] damage to plants, and reduction of plankton populations in the ocean's photic zone. This was ...
Since the late 1970s, the use of CFCs has been heavily regulated because of their destructive effects on the ozone layer. After the development of his electron capture detector , James Lovelock was the first to detect the widespread presence of CFCs in the air, finding a mole fraction of 60 ppt of CFC-11 over Ireland .
Starting in the 2010s, despite a global ban on the production of CFCs, five of these ozone-damaging emissions were on the rise. [ 5 ] The atmospheric abundance of CFC-13 rose from 3.0 parts per trillion (ppt) in year 2010 to 3.3 ppt in year 2020 based on analysis of air samples gathered from sites around the world. [ 10 ]
The small unabsorbed part that remains of UV-B after passage through ozone causes sunburn in humans, and direct DNA damage in living tissues in both plants and animals. Ozone's effect on mid-range UV-B rays is illustrated by its effect on UV-B at 290 nm, which has a radiation intensity 350 million times as powerful at the top of the atmosphere ...
For premium support please call: 800-290-4726 more ways to reach us
The ozone depletion potential (ODP) of a chemical compound is the relative amount of degradation to the ozone layer it can cause, with trichlorofluoromethane (R-11 or CFC-11) being fixed at an ODP of 1.0. Chlorodifluoromethane (R-22), for example, has an ODP of 0.05. CFC 11, or R-11 has the maximum potential amongst chlorocarbons because of the ...