Natural Phenomenon

Haze

  Haze is traditionally an atmospheric phenomenon where dust, smoke and other dry particles obscure the clarity of the sky. The World Meteorological Organization manual of codes includes a classification of horizontal obscuration into categories of fog, ice fog, steam fog, mist, haze, smoke, volcanic ash, dust, sand and snow Sources for haze particles include farming (ploughing in dry weather), traffic, industry, and wildfires.

  Seen from afar (e.g. approaching airplane) and depending upon the direction of view with respect to the sun, haze may appear brownish or bluish, while mist tends to be bluish-grey. Whereas haze often is thought of as a phenomenon of dry air, mist formation is a phenomenon of humid air. However, haze particles may act as condensation nuclei for the subsequent formation of mist droplets; such forms of haze are known as "wet haze."

  In the United States and elsewhere, the term "haze" in meteorological literature generally is used to denote visibility-reducing aerosols of the wet type. Such aerosols commonly arise from complex chemical reactions that occur as sulfur dioxide gases emitted during combustion are converted into small droplets of sulphuric acid. The reactions are enhanced in the presence of sunlight, high relative humidity, and stagnant air flow. A small component of wet haze aerosols appear to be derived from compounds released by trees, 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 favorable conditions each summer.

Arctic Haze

 

  Arctic haze is a phenomenon that occurs in the atmosphere at high latitudes in the Arctic due to air pollution. What distinguishes Arctic haze from haze found elsewhere, is the ability of its chemical ingredients to endure in the atmosphere for a longer period of time compared to other pollutants. Due to limited snowfall, rain, or turbulent air to displace pollutants from the polar air in the spring, Arctic haze can continue for more than a month in the northern atmosphere.

  Arctic haze was first discovered in 1750 when the Industrial Revolution began. Explorers could not determine where the foggy atmosphere was coming from. Norwegian explorer Fridtjof Nansen found dark stains on the ice surface when he explored the region more than a century ago. The actual term “Arctic haze” wasn’t coined until 1956 by Murray Mitchell, a U.S. Air Force officer stationed in Alaska. He used the term to describe an unusual reduction in visibility observed by American weather reconnaissance missions. When pilots of planes are in a layer of Arctic haze, they report that horizontal visibility drops to as much as one tenth that of normal clear sky. It was not known if the haze was a natural phenomenon at that time or if it had been formed by other pollutants, so no other research had been done in the next 18 years.

  The haze here is seasonal and peaks in the late winter and spring. The haze is generally formed by pollutants that come from thousands of miles away. Most of the pollutants are thought to originate from coal-burning in the mid-northern latitudes, especially from Asia. These aerosols contain about 90% sulfur and 10% carbon. This chemical makeup gives the haze a reddish color. This pollution is contributing to the warming of the Arctic region at a rate greater than any other place on Earth. Greenhouse gases are the main contributor, however. In the winter this rapidity in warming is increased by the loss of sunlight. The layer of haze acts as a trap, holding the infrared radiation in longer, thus warming the surface and atmosphere.

  There are many contributors to the warming of the Arctic. Besides greenhouse gases and pollution from industry, other sources include: ship emissions, smoke from forest fires, aerosol and ozone pollutants (mercury, aluminum, vanadium, manganese). Carbon dioxide released from factories and pollution of automobile emissions contributes to pollution that warms the Arctic a few degrees. Many people perceive the Arctic as a cold, pure and clean region of Earth. They are correct on the cold part. Pure and clean, may be misconceptions as pollution travels more and more into the Arctic regions.

  Many researchers have studied the effects of Arctic haze and more and more is being learned of how this phenomenon is affecting our planet. Climatologists from Europe predict that by the end of the 21st century, the Arctic region may rise 5 degrees Fahrenheit on an average day. The summer sea ice of the Arctic may also disappear completely by 2040 if warming continues. More pollution and stronger climate changes are predicted as a result of Arctic oil drilling. Because of global warming, The Arctic region is seeing a rise in rainfall that soon freezes afterward. This process is putting a huge strain on the animals of this region and with the continued effects of Arctic haze, the whole environment is at serious risk.