forest fires

Wildfires And Cancer Risk | Earth Wise

June 20, 2022 By EarthWise Leave a Comment

Hotter and drier conditions are leading to an increasing number of wildfires in North America and elsewhere around the globe. Scientists have linked the severe heat and drought that fuel these wildfires to climate change. As the climate continues to change, wildfires are projected to become more prevalent, more severe, and longer in duration.

According to a United Nations report released earlier this year, the Western U.S., northern Siberia, central India, and eastern Australia have already seen an uptick in wildfires. The likelihood of catastrophic wildfires globally could increase by a third by 2050 and more than 50% by the turn of the century.

According to a new study by researchers from McGill University, living near regions prone to wildfires may boost the risk of developing serious health issues. The study, which tracked more than two million Canadians over a period of 20 years, found a higher incidence of lung cancer and brain tumors in people exposed to wildfires. People living within 50 kilometers of wildfires during the past 10 years had a 10% higher incidence of brain tumors and a 4.9% higher incidence of lung cancer when compared to people living further away.

This study, which was recently published in The Lancet Planetary Health, is the first to examine how proximity to forest fires may influence cancer risk.

In addition to the impacts on air quality, wildfires also pollute aquatic, soil, and indoor environments. While some pollutants return to normal levels shortly after the fire, many others persist in the environment for long periods of time.

The research team notes that additional work is needed to develop more long-term estimates of the chronic health effects of wildfires.

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Exposure to wildfires increases risk of cancer

Climate change is causing more wildfires and governments are unprepared, says U.N.

Photo, posted August 17, 2020, courtesy of USFS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Air Pollution Reduction And Global Warming | Earth Wise

April 13, 2021 By EarthWise Leave a Comment

The world is dealing with two serious problems affecting the atmosphere: the growing levels of carbon dioxide leading to a warming climate and the effects of air pollution on human health. It turns out that these two things are connected in complicated ways.

Countries around the world are racing to mitigate global warming by limiting carbon dioxide emissions. The combustion of fossil fuels as well as wood and other biomass produces sulfate aerosols, which are associated with acid rain as well as many human health problems. Air pollution causes an estimated seven million premature deaths per year worldwide, so reducing it is imperative.

The complication is that sulfate aerosols in the upper atmosphere actually have a cooling effect on surface air temperatures. Aerosols create bigger clouds and increase light scattering, both of which result in less sunlight reaching the surface. Large natural sources of sulfate aerosols – such as volcanic eruptions – can temporarily cool the earth until they settle out of the atmosphere.

There are many kinds and sizes of atmospheric aerosols, making predicting their effects and behavior difficult. For example, black carbon aerosols from forest fires tend to suppress cloud formation by warming the air and making tiny water droplets evaporate. However, sulfate aerosols from burning fossil fuels make clouds grow larger.

Analysis has shown that air pollution has actually reduced the amount of warming that has taken place to date. A new study by Kyushu University in Japan looked at the long-term climate effects of reductions in sulfate aerosols. The loss of cooling effect from light-scattering aerosols as emissions are reduced is a factor that cannot be ignored.

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Air pollutant reductions could enhance global warming without greenhouse gas cuts

Photo, posted January 23, 2021, courtesy of Wutthichai Charoenburi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Lockdown Cleans Up Indian Air | Earth Wise

May 13, 2020 By EarthWise Leave a Comment

Our stories often discuss how human activities change the natural environment. With most of us confined to our homes, the lack of human activities is having profound effects on the environment. We are talking about some of these this week.

India suffers from some of the worst air pollution in the world. Of the most polluted cities in the world, 21 out of 30 were in India in 2019. According to World Health Organization standards, at least 140 million people in India breathe air containing 10 times or more greater levels than the safe limit for pollutants. Air pollution contributes to the premature death of 2 million Indians every year.

Half of India’s air pollution comes from industry, 27% from vehicles, and 17% from crop burning. Crop burning is prevalent because it is much cheaper than mechanical tilling after the harvest.

On March 25, the Indian government placed its 1.3 billion citizens under a strict lockdown to reduce the spread of COVID-19. The country-wide mandate decreased activity at factories and drastically reduced car, bus, truck, and airplane traffic.

Within one week, NASA satellite sensor observed aerosol levels at a 20-year low for this time of year in northern India. Aerosols are tiny solid and liquid particles suspended in the air that reduce visibility and can damage the human lungs and heart. Some aerosols have natural sources, such as dust storms, volcanic eruptions, and forest fires. But many come from human activities such as the burning of fossil fuels and croplands. Scientists expected to see changes in atmospheric conditions during the Indian lockdown, but the current changes are dramatic. They also present a unique opportunity to separate how natural and human sources of aerosols affect the atmosphere.

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Airborne Particle Levels Plummet in Northern India

Photo, posted April 29, 2020, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Extreme Weather Increasing

May 11, 2018 By EarthWise Leave a Comment

It sure seems like extreme weather is increasingly common: floods, droughts, extreme rainfall, powerful snowstorms, hurricanes and so on. But we tend to focus on recent events and often give them undue emphasis. So, it is reasonable to ask whether extreme weather really is more common these days.

Air Pollution Reducing Global Warming

April 12, 2018 By EarthWise Leave a Comment

Pollution particles emitted by diesel cars and trucks, coal-fired power plants, factories, primitive cook stoves, and the burning of forests are major contributors to the pervasive air pollution that plagues many cities and regions of the world. In India and China, such pollution leads to hundreds of thousands of deaths each year. And countries around the world are working hard to reduce pollution.