Aerosols - tiny particles suspended in the air - play a complex and critical role in both environmental systems and human health. They originate from natural sources like wildfires, as well as human activities such as industrial emissions, vehicle exhaust, cooking and agricultural burning. Though microscopic, aerosols have outsized impacts on public health, and their effects on global climate remains one of the largest uncertainties in climate science.

​

Aerosols are central to atmospheric chemistry because they influence air quality, climate, and cloud processes in ways that are both direct and complex. These fine particles range from natural dust and sea salt to soot and secondary organic aerosols formed from gas-to-particle conversion, and affect how sunlight is scattered and absorbed, shaping the Earth’s radiative balance. They also serve as nuclei for cloud formation, altering cloud reflectivity, and precipitation patterns.

​

Globally, aerosol species like Black Carbon (BC) are also considered Short-Lived Climate Forcers (SLCF), whereby scientific research is needed to standardise measurement and reporting to drive effective control actions and achieve near-term results in limiting global warming. According to UNEP and CCAC (Climate & Clean Air Coalition) assessments, aggressive SLCF mitigation could reduce global warming by 0.6 °C by 2050.

​

Understanding the origin and speciation of aerosol in the context of transboundary pollution is vital for regional cooperation, particularly in areas like monsoon Southeast Asia, where haze events and crop-burning practices cross national borders.