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SEI Initiative on Low Emission Development Pathways

This initiative focuses on integrated analysis and planning for the mitigation of air pollution and greenhouse gases, including short-lived climate pollutants, with the goal of achieving multiple benefits.

Inactive project


Initiative contact

Charles Heaps /

The SEI Initiative on Low Emission Development Pathways ended in 2019. You can find a summary of the key results and achievements from the initiative here

National leaders increasingly recognize the need to shift to low-emission economic pathways, both to address the urgent threat of climate change, and to ensure that development is sustainable. At the same time, many countries have made it a priority to combat air pollution, particularly in urban areas.

Synergies between both goals have long been recognized, but in practice, there has been little integration. The SEI Initiative on Low Emission Development Pathways (LED-P) aims to help bridge this gap by providing national-scale decision-makers with the tools and knowledge they need to consider climate and air quality measures together, and thus identify the low-emissions development opportunities that will yield the greatest benefits for their countries.

Many low-carbon strategies offer development benefits that go beyond climate change mitigation, including substantial reductions in air pollution – for example, when coal power is replaced by solar or wind power. There is also growing interest in combatting short-lived climate pollutants (SLCPs) – including methane, black carbon, tropospheric ozone and hydrofluorocarbons (HFCs) that can have a significant impact on climate change in the near term.

Yet decision makers, particularly in developing countries, lack crucial data on air pollution and greenhouse gas emissions, trends and the costs and benefits of different policy options. This makes it hard to identify and prioritize measures, or to make the case for action.

To help address this, this initiative will build capacity by creating an integrated framework to examine climate change (including long- and near-term mitigation) and air pollution together, along with easy-to-use planning and analytical tools. We will support these tools with training and information on the latest research and insights on key issues, and also work to synthesize that information and gather available data to support decision-making. In addition, we will undertake new research to fill knowledge gaps and help answer pressing questions that arise in policy and planning discussions.

Smog hangs over Mexico City, Mexico

Smog hangs over Mexico City, where planners are finding synergies between reducing GHGs and improving air quality e.g. by including black carbon (an important constituent of PM2.5) in their Nationally Determined Contribution (NDC) under the UNFCCC 2015 Paris Agreement. Photo: Sanpani / Flickr.

A new perspective

Efforts have been made in recent years to bring climate and air quality experts and policy-makers together, yet much more needs to be done. Too often policy development occurs in silos, so climate decision-makers pay little attention to air quality issues, and vice-versa. This results in missed opportunities to achieve gains in both realms at once.

In many countries, CO2 emission reduction is understandably not the highest priority, so being able to improve air quality through mitigation actions could greatly improve their political viability. Some air quality measures can also exacerbate the CO2 problem, and it is important to identify and avoid those risks. Countries need robust evidence and expertise to understand the potential trade-offs and synergies between different policies in order to develop more coherent and effective policies.

The LED-P initiative draws on SEI’s expertise in model development and application, capacity building for emission estimation and scenario-building, and impacts and benefits estimation covering climate change, human health and ecosystem impacts, valuation of impacts, costs of measures, and pathways to the successful implementation of the measures that can reduce the climate and air quality impacts.

Simplified view of SEI's integrated approach
A simplified view of SEI’s integrated approach showing that there are multiple benefits for climate, air quality and crop yields when measures are implemented to control carbon dioxide (CO2), black carbon (BC), fine particulate air pollution (PM2.5; that includes BC), methane (CH4) and ground-level (or tropospheric) ozone (O3) simultaneously.

Building on SEI and CCAC assets

SEI’s Long-range Energy Alternatives Planning (LEAP) system, used by thousands of planners, analysts and researchers worldwide, is already the go-to tool for countries undertaking integrated climate mitigation planning, especially in the developing world, and for creating Low Emission Development Strategies (LEDS).

The initiative will also build on work done by SEI for the Climate and Clean Air Coalition to Reduce Short-Lived Climate Pollutants (CCAC). We are extending LEAP’s capabilities by linking it to a new Benefits Calculator that, drawing on the latest science, estimates the range of benefits achievable through different strategies, taking both climate and air pollution into account. The integrated tool will help policy-makers and sustainability practitioners chart low-emissions development strategies that maximize benefits in line with national priorities, and understand all options and trade-offs.

The tools and knowledge will feed directly into capacity-building activities that are already planned and financed, including SLCP strategy development in 12 countries – Bangladesh, Chile, Colombia, Cote d’Ivoire, Ghana, the Maldives, Mexico, Morocco, Nigeria, Peru, the Philippines and Togo – under the CCAC national planning initiative. In 2018 work also started on training on emission inventory development for black carbon with Benin, Chad, Democratic Republic of the Congo Ethiopia, Guinea, Liberia, Mali, South Africa and Zimbabwe (includes all pollutants and planning and scenario building aspects of LEAP-IBC).

SEI will also bring these new capabilities to our ongoing LEAP capacity-building and policy engagement activities. The goal is to ensure local ownership of the tools, so the results that inform decision-making in each country are produced (or co-produced) by analysts in those countries, building trust and facilitating uptake.

Stories and Media

LEAP-IBC – energy, climate and health calculator

SEI’s energy planning tool, LEAP – the Long-range Energy Alternatives Planning system – is used by governments all over the world and by organizations in almost 190 countries,  to help meet their climate commitments under the Paris Agreement. The LEAP team continues to develop the system, to allow policy-makers and other researchers to meet new and ongoing energy challenges, and develop innovative policy. A recent update is the new integrated benefits calculator – LEAP-IBC – which allows the user to quantify the number of premature deaths that could be avoided through reducing emissions, alongside impacts on global temperature.

Premature death is only one of the possible health outcomes of air pollution. LEAP-IBC can be applied to many others and will prove a vital tool for research into a range of health impacts.

Integrated solutions

LEAP-IBC is currently being used by policy-makers and planners in Bangladesh, Chile, Colombia, Côte d’Ivoire, Ghana, the Maldives, Mexico, Morocco, Nigeria, Peru, the Philippines, and Togo. Many governments use the platform to help meet their climate commitments under the Paris Agreement, but many are also using LEAP to integrate health co-benefits into their strategies.

Latest Updates on LEAP-IBC

SEI released new version of LEAP-IBC in February  2018, which builds on the major release in late 2017. Read our Impact story here.  The new version now supports use of IBC in multi-regional modelling and expands the number of countries supported by IBC from about 70 to 100. Plus, SEI has released the first 64-bit version of LEAP support for very large models.

Example of LEAP-IBC interface showing clean cookstoves mitigation measures scenario

Example of LEAP-IBC interface showing clean cookstoves mitigation measures scenario.

The LED-P initiative has worked with the The Climate and Clean Air Coalition(CCAC) for six years. The CCAC is a voluntary partnership of governments, intergovernmental organizations, businesses, scientific institutions and civil society organizations committed to improving air quality and protecting the climate through actions to reduce short-lived climate pollutants.

The CCAC supports actions on the ground through their 11 initiatives and the SNAP initiative (Supporting National Action and Planning on Short-Lived Climate Pollutants) is such an initiative where SEI is one of six leads.

Policy development affecting short-lived climate pollutant (SLCP) mitigation measures at the national level is important. However, support is needed for national governments in identifying and quantifying measures, and coordinating efforts to reduce emissions from SLCP sources.

SNAP objectives

The SNAP programme was designed to achieve stronger action at the national scale by enhancing the ability of supported countries to develop, coordinate and implement SLCP mitigation across governments and

  • support governments in identifying opportunities for action at the national scale to reduce emissions
  • enhance mechanisms to coordinate and integrate SLCP measures into relevant national strategies
  • build technical capacity to analyze emission sources and mitigation scenarios and their benefits for health and climate
  • promote outreach to encourage SLCP mitigation action beyond participating countries
  • promote knowledge sharing among participating countries.

Countries participating in SNAP

We are working closely with a number of countries to develop their national planning to take further action on reducing the emissions that will prevent health impacts of air pollution and reduce the rate of near-term global warming. Details of the progress of addressing these emissions in countries are outlined in a number of fact sheets developed for the CAC SNAP initiative by SEI with the countries and with inputs from the CCAC secretariat and USEPA (a lead partner in the SNAP initiative).

Countries participating in LEAP

Click to download country fact sheets: Colombia Côte d’Ivoire Ghana Mexico Nigeria Peru

Short-lived climate pollutants

Chimney with smoke

Short-lived climate pollutants (SLCPs) are a group of pollutants that contribute to climate change by warming the atmosphere in the near-term, and to degraded air quality, with associated impacts on human health and vegetation. SLCPs include Black Carbon, a component of particulate matter (PM2.5), tropospheric ozone, methane and hydrofluorocarbons. The multiple impacts of SLCPs means that actions that can reduce SLCPs in the atmosphere can potentially result in multiple benefits, from reducing near term temperature increases, to reducing negative health effects associated with air pollution exposure, to increasing yields of crops like wheat, rice, maize and soybean.

Research that SEI has contributed to in this area focuses on:

  1. identifying the co-benefits that could result from reducing SLCPs in different policy arenas e.g. UNEA Resolutions, UNFCCC and SDGs
  2. investigating the measures and policies that could be implemented to achieve these reductions, and
  3. communicating these results to provide policy makers and implementers with a better understanding of the most important actions they can take to reduce SLCPs, and the likely benefits that these actions will derive.



Health impacts

People on motorcycles wearing masks

Air pollution, such as particulate matter and ozone, when breathed in can penetrate deep into the lungs and result in negative effects on human health. Quantifying the effects of air pollution on human health is important to allow the air pollution risk factor to be placed in the context of all other risk factors that affect human health. In addition, estimating changes in the air pollution health burden from taking specific actions to reduce air pollution emissions can provide policy makers with key information regarding the effectiveness of implementing a particular policy. SEI has contributed to research which has focussed on quantifying the current effects of air pollution on a broader range of health outcomes, for example estimating the global impact of maternal particulate matter exposure on the frequency of preterm birth, and quantifying future changes in air pollution health impacts from emission reduction strategies.



Impacts to vegetation

Short-lived Climate Pollutants (SLCPs) can influence vegetation through a number of different mechanisms of which the most important are likely to be:

  1.  the pytotoxic effect of ozone on growth, biomass and yield;
  2. aerosol changes to the quantity and quality of incoming solar radiation that will affect photosynthesis and consequent growth, biomass and yield; and
  3. through changes in regional climate e.g. aerosol affecting precipitation patterns, which will affect plant productivity.

SEI research over the past 20 years has mostly focussed on assessing the deposition and damage resulting from ozone to vegetation (crops, forests and grasslands). This research has included the development and application of a model called DO3SE, that is used to estimate both stomatal and non-stomatal deposition of ozone to vegetated surfaces. This model has been used to develop ozone ‘critical levels’ for European crop and tree species, essentially air quality guidelines for vegetation. Application of the DO3SE model within atmospheric chemistry transport models allows both ozone deposition and the exceedance of critical levels, and hence likely risk to vegetation from ozone, to be assessed.

In addition, SEI has contributed to experimental research that has estimated the damage from ozone to a variety of crops in different settings, including Asia and Africa. These studies improve the ability to assess the impact of ozone on a wider range of vegetation types, and in those areas where highest ozone concentrations are experienced. The DO3SE model is now being developed to estimate the effect of a range of environmental conditions/stresses including ozone, aerosol, nitrogen availability and soil water stress.



Poverty, gender and social equity

LED-P is concentrating on low and middle income countries to give them the knowledge and tools they need to plan emission reductions. We will be considering the health outcomes for different socio-economic groups, as the poor are often exposed to a greater degree to air pollution than more affluent people. And, women and children in the poorer sections of societies in Africa, Asia and Latin America are disproportionately exposed to pollution from cooking on stoves using biomass, and have to spend a lot of time searching for fuelwood. We are trying to quantify these different aspects of the issue in LEAP-IBC to the fullest extent possible and to also develop training material about gender and poverty issues related to the questions on climate and air quality and SLCP mitigation. As part of the concern SEI has for impacts on poor people, a project has linked with community champions in informal settlements of Nairobi and they have carried particle monitors and GPS around the city. This work is being followed up in the activities of the Kenya Air Quality network coordinated out of SEI Africa.




2018 portrait of Charlie Heaps
Charles Heaps

Senior Scientist


Kevin Hicks

Senior Research Fellow

SEI York

Johan C.I. Kuylenstierna

Reader / Research Leader

SEI York

Chris Malley

Senior Research Fellow

SEI York

Måns Nilsson
Måns Nilsson

Executive Director

SEI Headquarters

Mbeo Ogeya
Mbeo Ogeya

Research Fellow

SEI Africa

Philip Osano
Philip Osano

Centre Director

SEI Africa

Georgia Savvidou
Georgia Savvidou

Research Associate

SEI Headquarters

Andriannah Mbandi

SEI Affiliated Researcher

SEI York

Anneli Sundin
Anneli Sundin

Communications and Impact Officer

Project Communications

SEI Headquarters

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