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The UV index is a linear scale that measures the intensity of UV radiation with respect to sunburn. ... though ozone depletion is now ... a world-record ground-level ...
Ground-level ozone (O 3), also known as surface-level ozone and tropospheric ozone, is a trace gas in the troposphere (the lowest level of the Earth's atmosphere), with an average concentration of 20–30 parts per billion by volume (ppbv), with close to 100 ppbv in polluted areas.
Dobson spectrophotometers can be used to measure both total column ozone and profiles of ozone in the atmosphere. [5] [6] Ozone is tri-atomic oxygen, O 3; ozone molecules absorb harmful UV light in the atmosphere before it reaches the surface of the earth. No UVC radiation penetrates to the ground as it is absorbed in the ozone-oxygen cycle.
Decreases in ozone amounts lead to increases in UV radiation. Calculations of UV irradiance based on relationships with total ozone and total irradiance suggest that UV irradiance has increased since the early 1980s by 6-14% at more than 10 sites distributed over mid- and high latitudes of both hemispheres.
Environmental indicator criteria and frameworks have been used to help in their selection and presentation. It can be considered, for example, that there are major subsets of environmental indicators in-line with the Pressure-State-Response model developed by the OECD. One subset of environmental indicators is the collection of ecological indicators which can include physical, biological and ...
In fact, the UV Index Scale was created by the United States Environmental Protection Agency (EPA) ... When exposed to UV light, the skin’s DNA changes at a cellular level, and it may take many ...
Now that the ozone layer is thinner and the UV Index is used worldwide, it often reaches 15–20 in tropical territory, and 6 is indeed mild by comparison. If they had to start fresh today, I suspect they'd define the scale differently.
Most ozone monitors utilized in regulatory applications use ultraviolet absorption to accurately quantify ozone levels. An ozone monitor of this type operates by pulling an air sample from the atmosphere into the machine with an air pump. [3] During one cycle, the ozone monitor will take one air sample through the air inlet, and scrub the ozone ...