Three year average ozone concentrations within the central Arizona-Phoenix area, period 2003 to 2005

These data is part of the effort to provide the most detailed data on air quality in CAPLTER. This dataset represents spatially interpolated ozone (O3) levels as measured by monitroring stations of the Maricopa County Air Quality Department. O3 is a naturally occurring compound in which three oxygen atoms combine together. This is an unstable combination, and ozone is continually going through a natural cycle of being formed and then converting back to the more stable 'normal' double oxygen compound (O2). The cycle occurs fairly rapidly. In the stratosphere (6 miles and more above the earth), naturally occurring ozone has a beneficial effect of screening out harmful ultraviolet light from the sun. However, ground-level ozone is a pollutant and is a major component of the brown haze that is often observed in the Maricopa County valley. Ozone is not directly emitted into the air, but rather forms in a complex reaction that involves heat, sunlight, and a 'soup' of toxic pollutants, especially volatile organic compounds (VOCs). Some of the most common sources of VOCs are gasoline vapors, chemical solvents, and combustion products of fuels and consumer products. Ozone is created by sunlight acting on nitrates (NOX) and VOCs from motor vehicles and stationary sources, and can be carried hundreds of miles from their origins. Ozone affects the respiratory system in people and animals, and also affects the growth of plants.本数据集是为CAPLTER区域提供最详尽空气质量数据的工作的一部分。该数据集展示了由马里科帕县空气质量部门监测站测得的、经空间插值处理后的臭氧（O3）浓度水平。臭氧（O3）是由三个氧原子结合形成的天然化合物，其结合形态并不稳定，会持续处于自然循环中：不断生成，随后又转化为更稳定的"常态"双原子氧（O2）。该循环的发生速度相对较快。在平流层（地球上方6英里及更高空域）中，天然存在的臭氧可有效阻挡太阳发出的有害紫外线，发挥有益作用。但近地面臭氧属于污染物，也是马里科帕县河谷地区常见的棕色霾雾的主要组成成分。臭氧并非直接排放至大气中，而是通过复杂化学反应生成：该反应需要热量、光照，以及以挥发性有机物（VOCs）为代表的多种有毒污染物构成的混合体系。挥发性有机物的常见来源包括汽油蒸气、化学溶剂，以及各类燃料和消费品的燃烧产物。阳光照射机动车与固定源排放的硝酸盐（NOX）和挥发性有机物（VOCs）后，会生成臭氧；这类臭氧可被传输至距离其源头数百英里之外的区域。臭氧会对人类和动物的呼吸系统造成损害，同时也会影响植物的生长发育。