Recent studies have brought into light stark contrasts in air quality between cold regions, specifically comparing Dras in India and Fairbanks in Alaska. While Dras experiences extreme cold with healthy air quality, Fairbanks suffers from air pollution. This disparity raises questions about the factors influencing air quality in cold climates.
Temperature and Air Quality
Dras is known as the coldest place in India. Winter temperatures can plummet to -20º C. In contrast, Fairbanks records temperatures around -22.4º C. Despite the similar cold, Fairbanks faces severe air pollution. It ranks among the top polluted cities in the U.S., primarily due to particulate matter (PM).
About Particulate Matter
Particulate matter consists of tiny particles suspended in the air. It is classified into two categories – PM10-2.5 and PM2.5. PM2.5 particles are less than 2.5 micrometres in diameter. They are particularly harmful as they penetrate deep into the lungs, causing health issues such as asthma and cardiovascular diseases.
Pollution Sources in Fairbanks
In 2009, Fairbanks was declared a PM2.5 nonattainment area. Major pollution sources include emissions from wood stoves, industrial activities, and automobile exhaust. These sources release sulphur dioxide, contributing to high PM levels. A ban on high-sulphur fuel was implemented in 2022 to combat this issue.
Impact of Cold Weather on PM Chemistry
Recent research indicates that cold temperatures affect PM2.5 chemistry. Lower sulphate concentrations at extreme temperatures alter the acidity of PM particles. This change promotes the formation of hydroxymethanesulphonate, a component of PM2.5.
Hydroxymethanesulphonate Formation
Hydroxymethanesulphonate typically forms in clouds but can also occur in aerosols during winter in Fairbanks. This process is facilitated by supercooled liquid water present in aerosol particles. The acidity of these particles shifts rapidly, creating conditions conducive to hydroxymethanesulphonate production.
Role of Ions in Aerosol Acidity
The acidity of aerosol particles is influenced by the balance between sulphate and ammonium ions. Following the fuel ban, ammonium concentrations increased relative to sulphate, reducing overall acidity. This shift supports hydroxymethanesulphonate formation, further complicating air quality management in cold climates.
Global Implications
The findings from Fairbanks have broader implications for understanding air quality in cold regions globally. Researchers suggest that similar processes may occur in other cold urban areas. However, the relevance to regions in the Global South is limited, except in specific high-altitude areas.
Future Research Directions
Further studies are needed to explore these chemical processes in other cold regions. About how temperature variations affect air quality is crucial, especially in a warming world. This research could enhance strategies for managing air pollution in diverse climates.
Questions for UPSC:
- Examine the health impacts of particulate matter on urban populations.
- Discuss the role of temperature in influencing air quality in cold regions.
- Critically discuss the implications of aerosol chemistry for climate policy.
- What are the challenges faced by urban areas in managing air pollution? How can these be addressed?
Answer Hints:
1. Examine the health impacts of particulate matter on urban populations.
- Particulate matter (PM) can penetrate deep into the lungs, leading to respiratory issues.
- PM2.5 is linked to aggravated asthma and reduced lung function, particularly in vulnerable populations.
- Long-term exposure increases risks of cardiovascular diseases and premature death.
- Children and the elderly are especially susceptible to the harmful effects of PM.
- Public health initiatives often focus on reducing PM levels to improve urban air quality and health outcomes.
2. Discuss the role of temperature in influencing air quality in cold regions.
- Cold temperatures can alter the chemical composition of particulate matter, affecting its acidity.
- In colder climates, certain pollutants, like hydroxymethanesulphonate, can form under supercooled conditions.
- Temperature inversions in winter can trap pollutants close to the ground, worsening air quality.
- Low temperatures can reduce the effectiveness of emission controls, complicating air quality management.
- About temperature effects is crucial for developing region-specific pollution mitigation strategies.
3. Critically discuss the implications of aerosol chemistry for climate policy.
- Aerosol chemistry influences cloud formation and climate patterns, impacting weather systems globally.
- Changes in aerosol composition can affect the effectiveness of climate interventions, such as geoengineering.
- About secondary aerosol formation is vital for predicting air quality and climate interactions.
- Policies must consider the unique chemical behaviors of aerosols in different climatic conditions.
- Research findings can inform regulations on emissions and improve climate resilience strategies.
4. What are the challenges faced by urban areas in managing air pollution? How can these be addressed?
- Urban areas often face high emissions from vehicles, industrial activities, and residential heating.
- Political and economic factors can hinder the implementation of effective air quality regulations.
- Public awareness and education about air pollution’s health impacts are often insufficient.
- Technological advancements in monitoring and reducing emissions can be expensive and require investment.
- Collaboration between government, industry, and communities is essential for developing sustainable solutions.
