@misc{Ghimire, type = {Master Thesis}, author = {Ghimire, Dikshant}, title = {Assessment of the Impact of lockdown on PM 2.5 emission in Nepal}, school = {Hochschule Rhein-Waal}, abstract = {Air pollution has been one of the main concerns for Nepal for a very long and PM2.5 is one of the most neglected air pollutants in Nepal. Nepal is among the countries most affected by both indoor and outdoor PM2.5 pollution in the world. This thesis is based on the recent lockdown that happened in Nepal during the pandemic of COVID-19 in 2020. This study investigates the impact of lockdown on PM2.5 emission based on the assessment of emission inventories. The annual data for PM2.5 emission was extracted from EDGAR (Emissions Database for Global Atmospheric Research) and then the extrapolation was done to calculate the assumed PM2.5 emission for 2019 and 2020 using linear regression. The assumed nationwide monthly emission ercentage was used to calculate the PM2.5 emission during lockdown months. The PM2.5 sources affected during the lockdown were identified and their assumed percentage contribution (6.18\%) was used to calculate the emission during lockdown month. The ambient air PM2.5 concentration data was extracted from the official websites of the government of Nepal. The lockdown months were compared with the preceding year's same month and the percentage change was calculated. The study suggested that in 2020 the PM2.5 emission rate for April was reduced by 4.68\% and for May it was reduced by 4.85\% whereas during an assumed 'no lockdown' year, all the months would have had an increase in PM2.5 emission by ~1.6\%. The concentration of PM2.5 for March was educed by 14.65\%, similarly, for April it was reduced by 13.96\% and for May it was reduced by 50.92\%. The comparison of the percentage change of both the PM2.5 emission and concentration shows that the decrease in concentration was much higher compared to the reduction in emission due to the lockdown. The monthly assessment of PM2.5 during the lockdown suggested that the percentage change in emission of PM2.5 was minor compared to the change in the concentration of PM2.5 which might be due to different reasons including meteorology, underestimation of the contribution of some emission sectors by the emission inventories and the fact that the emission inventories are set up for the whole country whereas the PM2.5 concentration data are collected with monitoring stations located in cities close to major PM2.5 sources.}, language = {en} }