West coast cities face the world's worst air quality as wildfires rage

Four west coast cities in the US currently rank in the top 10 for worst air quality in the world, as wildfires rage up and down the western seaboard, cloaking the entire region in smoke.

Portland, Oregon, and Seattle, Washington, hold the No 1 and No 2 spots, while San Francisco and Los Angeles sit at four and six. Collectively, with the smoke from the wildfires, these four cities have knocked every city in China out of the top 10 for worst air quality.

With wildfires burning more than 3.3m acres in California, 1m acres in Oregon and more than 620,000 acres in Washington state, smoke from these blazes has nearly reached Hawaii to the west and Michigan to the east.

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Many in California are approaching a month of unhealthy air quality. The state’s fire season kicked off early with a freak barrage of dry lightning in mid-August that sparked a number of infernos, many of which are still burning. The August lightning siege, as firefighters refer to the event, resulted from nearly 14,000 lightning strikes that ignited more than 900 new wildfires. Warm temperatures and dry conditions have fueled additional fires since then. Six of the state’s 20 largest wildfires in its history are currently burning. At least 24 people have died.

Ash has rained down on cities such as Oakland, San Francisco, Sacramento, Los Angeles and San Diego for weeks now, blowing into the cracks of windows and covering surfaces. Local officials have warned residents to stay indoors and avoid outdoor physical activities. Unhoused Californians and residents forced to evacuate from the wildfires have faced particular challenges with finding shelter amid the current air quality that abides by social distancing. In Berkeley and Oakland, local lawmakers opened air respite centers for vulnerable unhoused residents.

Residents in Oregon and Washington are now experiencing what their California counterparts have gone through since mid-August. A heavy haze rests upon the Pacific north-west as wildfires leveled entire neighborhoods last week, killing at least 10 in Oregon. In Clackamas and Marion counties, large blazes remained completely uncontained.

The dense smoke mixed with the fog to create visibility issues at night.

Washington state residents met much of the same fate over the weekend, as the combined effect of the wildfires in Oregon and the dozens more burning in Washington sent plumes of smoke over the state.

Much hoped-for relief in the form of a weather system did not arrive on Monday, as expected, but the National Weather Service hoped that air quality conditions could begin improving later.

Scientists are already seeing the health effects of wildfire smoke exposure on residents, with Stanford University recording hospital admissions for asthma rise by 10% and cerebrovascular incidents such as strokes jump by 23% in the days following the August lightning siege in California.

Further complicating the health effects of the smoky air quality is a pandemic centered on a virus that affects the lungs. Researchers have expressed concerns that the unhealthy air quality will only intensify the risks of the Covid-19 pandemic, in terms of physical and mental health.