Smog, or smoke fog, is a type of intense air pollution. The word "smog" was coined in the early 20th century, and is a contraction (portmanteau) of the words smoke and fog to refer to smoky fog due to its opacity, and odor. The word was then intended to refer to what was sometimes known as pea soup fog, a familiar and serious problem in London from the 19th century to the mid-20th century. This kind of visible air pollution is composed of nitrogen oxides, sulfur oxide, ozone, smoke and other particulates. Man-made smog is derived from coal combustion emissions, vehicular emissions, industrial emissions, forest and agricultural fires and photochemical reactions of these emissions.
Selangor, also known by its Arabic honorific Darul Ehsan, or "Abode of Sincerity", is one of the 13 states of Malaysia. It is on the west coast of Peninsular Malaysia and is bordered by Perak to the north, Pahang to the east, Negeri Sembilan to the south and the Strait of Malacca to the west. Selangor surrounds the federal territories of Kuala Lumpur and Putrajaya, both of which were previously part of it.
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, traffic, industry, volcanic activity and wildfires. Seen from afar 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."
Kuala Selangor is a town in northwestern Selangor, Malaysia. It is the largest town and administrative centre of the coterminous Kuala Selangor District.
This article lists important figures and events in Malaysian public affairs during the year 1997, together with births and deaths of notable Malaysians.
The 2006 Southeast Asian haze event was caused by continued uncontrolled burning from "slash and burn" cultivation in Indonesia, and affected several countries in the Southeast Asian region and beyond, such as Malaysia, Singapore, southern Thailand, and as far as Saipan; the effects of the haze may have spread to South Korea. Local sources of pollution partly contributed to the increased toxicity, particularly in high-pollution areas such as ports, oil refineries, and dense urban areas. In the highly urbanised and industrialised Klang Valley of Malaysia in particular, the surrounding terrain acted as a natural retainer of polluted air, aggravating the situation when the haze set in.
The Air Pollution Index (API) is a simple and generalized way to describe the air quality, which is used in Malaysia. It is calculated from several sets of air pollution data and was formerly used in mainland China and Hong Kong. In mainland China the API was replaced by an updated air quality index in early 2012 and on 30 December 2013 Hong Kong moved to a health based index.
The Pollutant Standards Index (PSI) is a type of air quality index, which is a number used to indicate the level of pollutants in air.
The 1997 Southeast Asian haze was an international air pollution disaster that occurred during the second half of 1997, its after-effects causing widespread atmospheric visibility and health problems within Southeast Asia. Considered the most severe Southeast Asian haze event of all time, the total costs of the 1997 haze are estimated at US$9 billion, due mainly to health care and disruption of air travel and business activities.
The geography of Kuala Lumpur, Malaysia is characterized by a huge valley — known as the Klang Valley — bordered by the Titiwangsa Mountains in the east, several minor ranges in the north and the south and the Malacca Straits in the west. The name Kuala Lumpur literally means muddy confluence; Kuala Lumpur is located at the confluence of the Klang and Gombak Rivers, facing the Malacca Straits.
The Southeast Asian haze is a fire-related recurrent transboundary air pollution issue. Haze events, where air quality reaches hazardous levels due to high concentrations of airborne particulate matter from burning biomass, have caused adverse health, environmental and economic impacts in several countries in Southeast Asia. Caused primarily by slash-and-burn land clearing, the problem flares up every dry season to varying degrees and generally is worst between July and October and during El Niño events. Transboundary haze in Southeast Asia has been recorded since 1972 with the 1997 and 2015 events being particularly severe.
The 1997 group of forest fires in Indonesia that lasted well into 1998 were probably among the two or three, if not the largest, forest fires group in the last two centuries of recorded history.
The environment of Malaysia is the biotas and geologies that constitute the natural environment of Malaysia. Malaysia's ecology is megadiverse, with a biodiverse range of flora and fauna found in various ecoregions throughout the country. Tropical rainforests encompass between 59% to 70% of Malaysia's total land area, of which 11.6% is pristine. Malaysia has the world's fifth largest mangrove area, which totals over a half a million hectares.
Air pollution has been an ongoing problem in many countries in the Southeast Asia region, and Malaysia is one of the worst affected. Haze has been a major issue for the country, driven by slash and burn practices by farmers and peat fires blown by the wind from Indonesia.
The 2013 Southeast Asian haze was a haze crisis that affected several countries in Southeast Asia, including Brunei, Indonesia, Malaysia, Singapore and Southern Thailand, mainly during June and July 2013. The haze period was caused by large-scale burning in many parts of Sumatra and Borneo. Satellite imagery from NASA's Terra and Aqua satellites showed that the haze was mainly due to smoke from fires burning in Riau province, Indonesia.
The 2015 Southeast Asian haze was an air pollution crisis affecting several countries in Southeast Asia, including Brunei, Indonesia, Malaysia, Singapore, southern Thailand, Vietnam, Cambodia and the Philippines.
The fires since the mid-March has caused part of Sabah, especially in the West Coast Division to be blanketed by haze.
The 2016 Southeast Asian haze was an air pollution crisis which affected several countries in Southeast Asia, including Indonesia, Malaysia and Singapore.
The 2010 Southeast Asian haze was an air pollution crisis which affected many Southeast Asia countries such as Indonesia, Malaysia and Singapore during the month of October in 2010.
A trans-national air pollution crisis affected several countries in Southeast Asia from February to September 2019, including Brunei, Indonesia, Malaysia, the Philippines, Singapore, Thailand, and Vietnam.
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