Analysis of baseline and alternative air quality scenarios for Pakistan: an integrated approach

Black carbon emissions inventory and scenario analysis for Pakistan

Black carbon (BC) emissions, resulting from the incomplete combustion of carbonaceous fuels, have been extensively linked to adverse impacts on air quality, climate change, and public health. Nevertheless, there is currently a lack of a comprehensive analysis that integrates activity-based BC emissions inventory and scenario analysis at the national/regional, sectoral, and sub-sectoral levels in Pakistan. This study aims to fill this gap by conducting a comprehensive evaluation of Pakistan's BC emissions inventory for 2021 along projecting emissions until 2050 under the reference emission scenario (RES) and the accelerated reduction scenario (ARS) using the GAINS modeling framework to assess the potential impact of mitigation measures. This study takes a unique approach by considering commonly overlooked sources of BC emissions, such as kerosene lighting, brick kilns, diesel generator sets, and natural gas flaring, which are not typically included in conventional analyses. National BC emissions in 2021 were estimated at 181 kt, with residential combustion being the major contributor, accounting for more than half (108 kt) of the total emissions. The transport, industry, waste, agriculture, power plants, and fuel conversion sectors contributed 26.1 kt, 20.1 kt, 10.7 kt, 8.9 kt, 6.0 kt, and 0.9 kt, respectively. We anticipate that the total BC emissions in Pakistan will reach 201 kt under the RES and 41 kt under the ARS scenario by the year 2050. The ARS achieves substantial BC reductions by the adoption of cleaner fuels, improved biomass stoves, end-of-pipe emission control technologies with higher removal efficiencies, and implementing a ban on the open burning of waste and crop residues. This study underscores the considerable potential for reducing BC emissions across various sectors in Pakistan over the next three decades.

A Cross-Sectoral Investigation of the Energy–Environment–Economy Causal Nexus in Pakistan: Policy Suggestions for Improved Energy Management

This paper explored the energy–environment–economy (EEE) causal nexus of Pakistan, thereby reporting the causal determinants of the EEE nexus by employing the newly developed modified Peter and Clark (PC) algorithm. The modified PC algorithm was employed to investigate the causal ordering of energy consumption, CO2 emissions and economic growth across Pakistan’s domestic, industrial, transportation and agricultural sectors. An empirical comparison, i.e., following Monte Carlo simulation experiments demonstrates that the proposed modified PC algorithm is superior to the original PC proposition and can differentiate between true and spurious nexus causalities. Our results show that significant causality is running from energy consumption in industrial and agricultural sectors towards economic growth. There is no causal association between energy consumption and economic growth in the domestic and transportation sectors. On the other hand, causality runs from energy consumption in the transportation, domestic and industrial sectors towards CO2 emissions. It is concluded that energy consumption in industrial and agricultural sectors leads to economic growth alongside the associated CO2 emissions. On the other hand, the contribution of domestic and transportation sectors in economic growth is trivial with significant CO2 emissions. This paper provides novel empirical evidence of impacts of energy mismanagement at sectoral levels, economic output and environmental consequences; alongside policy recommendations for sustainable energy-based development on the national scale.

Modelling of sectoral emissions of short-lived and long-lived climate pollutants under various control technological strategies

In India, air pollution has been acknowledged as the fifth most imperative cause of mortality due to high emissions from burning of fossil fuels in industries (brick kilns and thermal power plants), biomass burning, agricultural residue burning and transportation. The emissions of black carbon (BC) with the other air pollutants (CO₂, CH₄, N₂O, HFC, PFC, and SF₆), is taking considerable attention in the world because of its ability to effect air quality and weather. The Indo-Gangetic Plains (IGP) region has been considered as one of the greatest source of emissions in India. The short lived climate pollutants (SLCPs) like BC, methane, tropospheric ozone and hydrofluorocarbons have been considered as a climate forcing agent along with CO₂. These pollutants have shorter lifetime in atmosphere compared to CO₂ and account for the 40-45% of global warming. Among them, BC has a great global warming ability and can increase the Earth's temperature much quicker than carbon dioxide. After CO₂, the second highest donors to global warming are CH₄ and BC. Recognising the importance of these pollutants, daily concentrations of BC, PM_2.5 and PM₁₀ were monitored in three district of IGP during January 2015 to December 2016. The GAINS model was used for assessment of pollution effects, emissions of SLCPs, GHGs and identifying appropriate control actions. The outcomes of modelling advocate that low carbon strategies are more competent to reduce emissions as compared to other control strategies. But, application of low carbon strategies would be restricted by the accessibility of clean fuels. In some cases, finance will be needed to support monitoring of air pollution and other supportive technologies.

Cleaner and Sustainable Energy Production in Pakistan: Lessons Learnt from the Pak-TIMES Model

The energy planning process essentially requires addressing diverse planning objectives, including prioritizing resources, and the estimation of environmental emissions and associated health risks. This study investigates the impacts of atmospheric pollution for Pakistan from the energy production processes under various modalities. A national-scale bottom-up energy optimization model (Pak-TIMES) with the ANSWER-TIMES framework is developed to assess the electricity generation pathways (2015–2035) and estimate GHG emissions and major air pollutants, i.e., CH4, CO, CO2, N2O, NOX, PM1, PM10, PM2.5, PMBC, PMOC, PMTSP, SO2, and VOC under five scenarios. These scenarios are: BAU (business-as-usual), RE-30 (30% renewables), RE-40 (40% renewables), Coal-30 (30% coal), and Coal-40 (40% coal). It is revealed that to reach the electricity demand of 3091 PJ in 2035, both the Coal-30 and Coal-40 scenarios shall cause maximum emissions of GHGs, i.e., 260.13 and 338.92 Mt (million tons) alongside 40.52 and 54.03 Mt emissions of PMTSP in both of the scenarios, respectively. BAU scenario emissions are estimated to be 181.5 Mt (GHGs) and 24.30 Mt (PMTSP). Minimum emissions are estimated in the RE-40 scenario with 96.01 Mt of GHGs and 11.80 Mt of PMTSP, followed by the RE-30 scenario (143.20 GHGs and 17.73 Mt PMTSP). It is, therefore, concluded that coal-based electricity generation technologies would be a major source of emission and would contribute the highest amount of air pollution. This situation necessitates harnessing renewables in the future, which will significantly mitigate public health risks from atmospheric pollution.

Mitigation pathways towards national ambient air quality standards in India

Exposure to ambient particulate matter is a leading risk factor for environmental public health in India. While Indian authorities implemented several measures to reduce emissions from the power, industry and transportation sectors over the last years, such strategies appear to be insufficient to reduce the ambient fine particulate matter (PM_2.5) concentration below the Indian National Ambient Air Quality Standard (NAAQS) of 40 μg/m³ across the country. This study explores pathways towards achieving the NAAQS in India in the context of the dynamics of social and economic development. In addition, to inform action at the subnational levels in India, we estimate the exposure to ambient air pollution in the current legislations and alternative policy scenarios based on simulations with the GAINS integrated assessment model. The analysis reveals that in many of the Indian States emission sources that are outside of their immediate jurisdictions make the dominating contributions to (population-weighted) ambient pollution levels of PM_2.5. Consequently, most of the States cannot achieve significant improvements in their air quality and population exposure on their own without emission reductions in the surrounding regions, and any cost-effective strategy requires regionally coordinated approaches. Advanced technical emission control measures could provide NAAQS-compliant air quality for 60% of the Indian population. However, if combined with national sustainable development strategies, an additional 25% population will be provided with clean air, which appears to be a significant co-benefit on air quality (totaling 85%).

Sectoral assessment of greenhouse gas emissions in Pakistan

In this study, an attempt has been made to develop inventory of greenhouse gas (GHG) emissions for Pakistan at the national and sectoral level. The emission profile includes carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O). In 2012, GHG emissions from different sectors of economy are estimated at 367 Tg CO₂eq. Out of this, CO₂ emissions were 179 Tg; CH₄ emissions were 107 Tg CO₂eq; and N₂O emissions were 81 Tg CO₂eq. Energy and agriculture sectors contribute approximately 89% of national GHG emissions. Industrial processes, waste, and land use change and forestry (LUCF) sectors contribute the remaining 11% GHG emissions. A comparison with the 1994 GHG emission inventory of Pakistan shows that GHG emissions in Pakistan from 1994 to 2012 have increased at an annual growth rate of 4.1% and yet anticipated to increase further for meeting the national developmental goals; however, the per capita emissions in Pakistan will remain low when compared with the global average.