Aerosols have severe effects on climate, human health and ecosystems. The impact of aerosols on climate, ecosystems and human health can be better understood if the variability of optical properties of aerosols is accurately known. In this paper, we have used Moderate Resolution Imaging Spectroradiometer (MODIS) datasets of aerosol optical depth (AOD) at 550 nm, Angstrom exponent (440/870) (AE) and enhanced vegetation index (EVI) over Pakistan. We have also analyzed the relationship between meteorological variables (e.g., temperature, relative humidity (RH) and wind speed (WS)) and aerosol optical properties to acquire a deep knowledge of aerosol variability. The coefficients of determination (R²) between Aqua-AOD and AERONET-AOD are found to be 0.6724 over Lahore and 0.7678 over Karachi. Aqua-AOD has also been validated with AOD data from Terra, MISR and SeaWiFS. High AOD (0.8–1) and low AE (0.4–0.8) have been observed over south and southwestern Pakistan indicating the presence of dust aerosols. In northeastern Pakistan, EVI is negatively correlated with AOD. The northeastern Pakistan is characterized by high values of AOD (∼1) during all seasons. AOD showed a significant interannual variation with the lowest values (0.22) in January and the highest (0.58) in July. AE is observed to be lower in spring and summer than in winter and autumn seasons in south and south-western Pakistan. A positive R (≥0.6) is observed between AOD and temperature over the southwestern Pakistan while a negative R (−0.4 ≤) is observed between AOD and RH over the southwestern Pakistan.

气溶胶会对气候，人类健康和生态系统产生严重影响。如果能准确了解气溶胶光学特性的变化，就可以更好地理解气溶胶对气候，生态系统和人类健康的影响。在本文中，我们使用了中度分辨率成像光谱仪（MODIS）数据集，包括巴基斯坦550 nm的气溶胶光学深度（AOD），埃指数（440/870）（AE）和增强的植被指数（EVI）。我们还分析了气象变量（例如温度，相对湿度（RH）和风速（WS））与气溶胶光学特性之间的关系，从而获得了对气溶胶可变性的深入了解。测定系数（R ²）发现Aqua-AOD和AERONET-AOD之间在拉合尔上为0.6724，在卡拉奇上为0.7678。Aqua-AOD也已通过Terra，MISR和SeaWiFS的AOD数据进行了验证。在巴基斯坦南部和西南部，观测到较高的AOD（0.8-1）和较低的AE（0.4-0.8），表明存在粉尘气溶胶。在巴基斯坦东北部，EVI与AOD呈负相关。巴基斯坦东北部的特点是所有季节的AOD值都很高（约1）。AOD年际变化显着，1月的最低值（0.22）和7月的最高值（0.58）。在巴基斯坦南部和西南部，春季和夏季的AE低于冬季和秋季的AE。在巴基斯坦西南部，AOD和温度之间的正值R（≥0.6）被观察到，而负值在巴基斯坦西南部的AOD和RH之间观察到R（-0.4≤）。