Mitigating the impacts of air pollutants in Nepal and climate co-benefits: a scenario-based approach

Short-lived climate pollutants (SLCPs) including black carbon (BC), methane (CH4), and tropospheric ozone (O3) are major climate forcers after carbon dioxide (CO2). These SLCPs also have detrimental impacts on human health and agriculture. Studies show that the Hindu Kush Himalayan (HKH) region, which includes Nepal, has been experiencing the impacts of these pollutants in addition to greenhouse gases. In this study, we derive a national-level emission inventory for SLCPs, CO2, and air pollutants for Nepal and project their impacts under reference (REF) and mitigation policy (POL) scenarios. The impacts on human health, agriculture, and climate were then estimated by applying the following: (1) adjoint coefficients from the Goddard Earth Observing System (GEOS)-chemical transport model that quantify the sensitivity of fine particulate matter (PM2.5) and surface O3 concentrations in Nepal, and radiative forcing in four latitudinal bands, to emissions in 2 × 2.5° grids, and (2) concentration–response functions to estimate health and crop loss impacts in Nepal. With the mitigating measures undertaken, emission reductions of about 78% each of BC and CH4 and 87% of PM2.5 could be achieved in 2050 compared with the REF scenario. This would lead to an estimated avoidance of 29,000 lives lost and 1.7 million tonnes of crop loss while bringing an economic benefit in present value of 2.7 times more than the total cost incurred in its implementation during the whole period 2010–2050. The results provide useful policy insights and pathways for evidence-based decision-making in the design and effective implementation of SLCP mitigation measures in Nepal

Environmental, energy security, and energy equity (3E) benefits of net-zero emission strategy in a developing country: A case study of Nepal

There is a growing number of national, subnational and even company targets for net-zero emissions of CO2 in support of the Paris Climate Agreement goals of limiting the global average temperature increase within 1.5 °C by 2100. The challenges faced by developing countries in achieving net-zero emissions targets are, however, very prominent due to their common desire for rapid economic growth, improved socio-economic conditions, and greater climate resilience. In addition, this has to overcome many constraints related to the competitiveness, acceptability, and sustainability of proposed and planned low-carbon initiatives. It is thus very important to understand the economic and technical characteristics of net-zero emissions concepts and pathways. The constraints can best be addressed if actual and transparent co-benefits related to these initiatives are identified and reflected during their implementation. Here we employ the Low Emissions Analysis Platform (LEAP) to examine Nepal’s recently introduced ‘Long-term Strategy for Net-zero Emissions’ and to estimate anticipated co-benefits in terms of reducing air pollutants emission and enhancing energy security and energy equity. Under the reference scenario (REF), the annual CO2 emission is expected to increase from 23 MtCO2 in 2019 to 79 MtCO2 in 2050 with significant increase in air pollutants emissions in the range of 60% (Organic Carbon) to 183% (SO2), increase in energy import dependency, reaching electricity consumption per capita below one-quarter of the world average. Under the ‘With Additional Measures (WAM)’ strategy scenario, air pollutants would be reduced in the range of 70% (Organic Carbon) to 85% (Black Carbon) respectively, in 2050 as compared to the REF. Similarly, it results drastic improvement in energy security indicators and energy equity. It is expected that the findings of this study will provide useful input to policymakers, private sector, societal actors and researchers in support of successful implementation of the initiatives for sustainable socio-economic transformation pathways