Pollution and Climate Smart Agriculture in China (PaCSAC)

Agriculture is a substantial contributor to emissions of greenhouse gases (GHGs) such as carbon dioxide, methane and nitrous oxide but is also impacted by the climate change caused by increased atmospheric concentrations of these GHGs. This situation has led to the 'climate smart agriculture' (CSA) approach that identifies agricultural management practices and technologies to reduce emissions, whilst simultaneously enhancing productivity and improving farmers' livelihoods. However, agriculture also contributes substantially to air pollution through emissions of nitrogen oxides, ammonia and aerosols in addition to the more well-known GHGs. Together these emissions contribute to air pollutants of which secondary ozone and aerosols (PM) are arguably the most important, damaging both human health and arable crop productivity.

These agricultural emissions contribute to substantial air quality problems in China. Poor air quality (due to elevated PM) is estimated to be responsible for between 0.35 to 1.2 million premature deaths per year in China. Ozone pollution has also been estimated to induce wheat yield losses of between 3 and 12% per year. However, the nature of these environmental challenges also offer opportunities for innovative solutions, specifically to extend the CSA approach to include air pollutant emissions and impacts and apply this in China. This will be explored in PaCSAC within four key research areas: The first will involve stakeholder engagement with farmer representatives and organisations to gain a better understanding of the feasibility of implementing alternative agricultural practices and technologies to reduce emissions. The second will translate this knowledge of feasible measures into quantified estimates of emissions associated with these different interventions; here we will partner with colleagues in Laos to explore the transferability of methods developed in this project to support agricultural burn assessment and subsequent air quality. Thirdly, we will combine existing models (TOMCAT and WRFChem), remote and in-situ observations to estimate the atmospheric ozone and aerosol concentrations, with a focus on Eastern China where agriculture is particularly important. Finally, impact assessments of the consequences of pollutant concentrations and associated climate variables, for a range of agricultural emission reduction scenarios, on crop productivity (namely rice and wheat) and PM effects on human health will be assessed using two existing tools - the DO3SE-crop model (for crops) and the LEAP-IBC tool (for human health and crops). These scenarios will be developed in partnership with IIASA who are supporting policy makers in China on low emission development. Importantly, these estimates of emissions, concentrations and impacts will incorporate new satellite, aerial and in situ observation monitoring technologies coupled with the expertise of our Chinese partners to improve modelling and ultimately, the identification of the sustainable solutions for agriculture.

To enable transfer of these new methodologies for application in other countries, PaCSAC will further develop and apply the LEAP-IBC tool. This is a decision support tool and represents a simplified, consolidated tool that incorporates the
emissions, concentration and impact estimates that are provided by the combination of the more complex models used in this project. LEAP-IBC is currently used by countries around the world to develop low emission development pathways, supported by the international 'Climate and Clean Air Coalition' organisation. This offers an exciting opportunity for the results of our project to be disseminated to a large number of countries supported by the CCAC. In the first instance we will work closely with Bangladesh to ensure that the improvement of the LEAP-IBC tool (and specifically the agricultural emissions associated with different interventions) is relevant outside of China.