Taxonomy term

air pollution

India's urban areas punch city-shaped holes in fog

Air pollution boosts fog formation in some places, creating whiteouts that can affect air and ground transportation, air quality, and public health. In northern and eastern India, persistent fog often hovers over the Indo-Gangetic Plain, a vast region dotted with several densely populated cities, including Delhi, home to 19 million people. Over some of these cities, however, satellite imagery is revealing large holes in the fog.

21 Jun 2018

Unexpected nanoparticles trace coal pollution

Coal burning produces an array of chemicals and particulates that, when released into the atmosphere, contribute to pollution, poor air quality and threats to public health. Measurements of particulate air pollution typically focus on particles called PM2.5, which have diameters of 2.5 micrometers or less. This group includes nano-sized particles, although these bits of minerals, dust and organics often go undetected because of their tiny size. In a new study, researchers sampling a coal ash spill have unearthed a type of nanoparticle not previously known to be produced by burning coal. While the particles might be useful in detecting pollution problems, they may also have consequences for human and environmental health.

24 Jan 2018

Benchmarks: December 5, 1952: The Great Smog smothers London

On Friday, Dec., 5, 1952, a blanket of thick, yellow smog settled over London, cloaking the city for five days straight. Smog wasn’t uncommon — Londoners called these days “pea-soupers,” based on the yellow-black color — and there were notable smog episodes from the Industrial Revolution (late 1700s) through the 1950s. But the haze of the city’s infamous “Great Smog” of 1952 long overstayed its visit. The lingering smog killed thousands, and its residual effects lasted for decades.

05 Dec 2017

Dust influences pollution levels in eastern China

Air pollution often enshrouds cities in eastern China in a thick haze that impairs visibility and causes respiratory health problems. Emissions from human activity are mainly to blame, but climate researchers now report that natural forces — namely, dust kicked into the air by wind — can also exert a strong control over how much pollution persists in the air.

22 Aug 2017

Chinese air pollution clears up mystery of London's 1952 hazardous haze

In December 1952, a fatal fog crept through London for almost five days, smothering the city in a yellow haze that reeked of rotten eggs. The “Great Smog,” as it was called, caused up to 12,000 deaths and left more than 150,000 people hospitalized in the worst air pollution event in European history. The calamity sparked the British Parliament to pass the Clean Air Act in 1956, but the exact chemical processes that caused the event have remained a mystery, until now.

03 Mar 2017

Burning grass releases more nitrogen pollution than burning wood

Smoke from fires — whether from wildfires or from residential and agricultural grass and crop burning — carries pollutants into the air that affect climate and can be toxic to humans and ecosystems. According to new research, smoke from crop and grass fires appears to contain higher levels of some hazardous nitrogen-containing chemicals than wood fire smoke. The work also calls into question whether certain chemicals commonly used as distinctive signatures of biomass burning are still valid.

06 Feb 2017

Kilauea increases asthma risk

Kilauea may be best known for its picturesque red lava flowing into the ocean, but new research presented this week at the Geological Society of America annual meeting in Denver, Colo., suggests that locally, the volcano may be known for something more dangerous: asthma. The new study links gaseous eruptions from the Hawaiian volcano to increased asthma risk for those living downwind, especially children.

 
28 Sep 2016

Sunlight liberates nitrogen from urban grime

Cities are dirty. That’s obvious from all the grime that collects on glass, metal and other urban surfaces. But new research shows that not everything in that grunge is staying put at ground level, and that the grime — and the nitrogen in it — is contributing to air pollution in ways scientists aren’t accounting for.
 
24 Dec 2015

Secondary aerosols a primary cause of Chinese smog

Images of Chinese skylines and streetscapes blurred by pollution-fueled hazes have become increasingly common in recent years amid ongoing urbanization and industrialization. According to a new study published in Nature, much of the pollution fogging the country’s major cities is arising not from fine particles emitted directly into the sky, but by gases that react and condense in the atmosphere to form secondary aerosols.

24 Jan 2015

Acid rain recovery in the Northeast

Four decades after the passage of the Clean Air and Clean Water Acts, the acid rain that plagued the Northeast is still diminishing. The amount of sulfate and nitrate found in Northeastern lakes is not only declining, but the decrease has been speeding up, according to a long-term study recently published in Environmental Science & Technology.

10 Oct 2014

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