| Abstract from DBPedia | Haze is traditionally an atmospheric phenomenon in which dust, smoke, and other dry particulates suspended in air obscure visibility and the clarity of the sky. The World Meteorological Organization manual of codes includes a classification of particulates causing horizontal obscuration into categories of fog, ice fog, steam fog, mist, haze, smoke, volcanic ash, dust, sand, and snow. Sources for particles that cause haze include farming (ploughing in dry weather), traffic, industry, volcanic activity and wildfires.Seen from afar (e.g. an approaching airplane) and depending on the direction of view with respect to the Sun, haze may appear brownish or bluish, while mist tends to be bluish grey instead. Whereas haze often is thought of as a phenomenon occurring in dry air, mist formation is a phenomenon in saturated, humid air. However, haze particles may act as condensation nuclei that leads to the subsequent vapor condensation and formation of mist droplets; such forms of haze are known as "wet haze." In meteorological literature, the word haze is generally used to denote visibility-reducing aerosols of the wet type suspended in the atmosphere. Such aerosols commonly arise from complex chemical reactions that occur as sulfur dioxide gases emitted during combustion are converted into small droplets of sulfuric acid when exposed. The reactions are enhanced in the presence of sunlight, high relative humidity, and an absence of air flow (wind). A small component of wet-haze aerosols appear to be derived from compounds released by trees when burning, such as terpenes. For all these reasons, wet haze tends to be primarily a warm-season phenomenon. Large areas of haze covering many thousands of kilometers may be produced under extensive favorable conditions each summer.煙霧（えんむ、英: haze）とは、目に見えない乾いた微粒子が大気中に浮遊していて、視程が妨げられている現象。気象観測上は、視程が10km未満になっているとき。また煙霧のとき、湿度は75%未満の場合が多い。発生源は、地面から舞い上がったちりや砂ぼこり、火事による煙、工場や自動車からのばい煙などさまざま。なお、大気汚染が原因であることが明らかな煙霧は「スモッグ」とも呼ばれる。 微粒子が太陽光を散乱するため、多くの場合は景色が乳白色に濁って見える。背景が明るいか、遠くに明るい色の物体があるときには、背景や物体は黄味を帯びた色、あるいは赤味を帯びた色になる。反対に暗いときには、青味がかった色になる。また、粒子自身に色が付いている時にはその色が反映される。これに対して、湿った微粒子で生じる靄（もや）は灰色を呈することから、両者は区別されている。 (Source: http://dbpedia.org/resource/Haze) |
