A study reveals that reducing aerosol emissions in India without concurrently cutting greenhouse gases may accelerate warming. This has significant implications for vulnerable populations in regions already facing severe pollution. Experts underscore the importance of developing comprehensive policies that address both pollution types while enhancing adaptation measures to safeguard human health and environmental integrity.
India is currently faced with the dual challenge of improving air quality while mitigating the impacts of climate change. A recent study published in Geophysical Research Letters indicates that rapidly reducing aerosol emissions without simultaneously addressing greenhouse gas emissions could result in an accelerated pace of warming, especially impacting vulnerable populations in polluted regions. The study emphasizes that areas which improved air quality in the late 20th century have seen an increase in warming trends, while densely populated urban regions with lower developmental indices have experienced less warming due to the masking effect of pollution.
Global warming is primarily a consequence of accumulating greenhouse gases, which exacerbate temperature and rainfall extremes. Aerosols, which include pollutants such as sulphates, scatter solar radiation and have a cooling effect, thereby somewhat balancing the heat trapped by greenhouse gases. The brief atmospheric lifespan of aerosols contrasts with the long-term presence of greenhouse gases, complicating the climate response.
Prof. Govindasamy Bala from the Indian Institute of Science highlights the relationship between industrial activities, fossil-fuel emissions, and aerosol generation in India. Thermal power plants, responsible for approximately 70% of India’s electricity, emit sulphur, which forms sulphate aerosols – critical contributors to regional aerosol composition. Prof. Bala points out that sulphate aerosols make up 50-60% of aerosols in the area, indicating the need for emission control at the source to effectively reduce air pollution.
Prof. Krishna AchutaRao shares insights on India’s temperature rise between 1906 and 2005, attributing a significant portion of warming to greenhouse gases while noting that cooling from aerosols has mitigated some of these effects. According to an assessment from the Ministry of Earth Sciences, India’s temperatures have increased by about 0.7°C from 1901 to 2018, suggesting a partial offset from anthropogenic aerosols and land-use changes.
The implications of aerosol reductions for rainfall patterns are complex. While removing aerosols leads to increased temperatures, precipitation impacts remain uncertain. Bala notes that aerosol cooling is unequally applied across hemispheres, affecting Indian monsoon rainfall. Studies indicate that reducing aerosols may also trigger adverse consequences for rainfall patterns, necessitating a thorough approach to understanding these dynamics.
The connection between industrial activities and both aerosol and greenhouse gas pollution poses compounded health risks, particularly in vulnerable populations. The research advocates for the development of policies that simultaneously address both pollution types, while also preparing for the potential short-term repercussions of increased warming. As acknowledged by Sengupta, merely achieving net-zero carbon emissions does not conclude the climate dialogue; adaptation strategies for at-risk groups must also be prioritized.
Experts emphasize the need for enhanced heat action plans in Indian cities to handle potential increases in heat stress due to reduced aerosol levels. A recent report from Sustainable Futures Collaborative highlights deficiencies in existing plans, urging better-targeted actions for urban areas to combat warming while acknowledging the health benefits of air quality improvements. Ultimately, experts agree that the advantages of reducing pollution on human health surpass the potential downsides posed by increased temperatures or altered precipitation patterns.
In summary, India faces the critical task of balancing air quality improvement with climate change mitigation. Rapid reductions in aerosol emissions without addressing greenhouse gas emissions can lead to accelerated warming, particularly affecting vulnerable populations. The study emphasizes the necessity of effective policies to manage both pollution types while preparing for the implications of climate change, particularly in urban areas. Continued research and strategic planning are essential for ensuring public health and environmental sustainability moving forward.
Original Source: www.thehindu.com
