PIK has cooperated with the FAO to advance research on the quantification of agricultural losses and damages caused by climate change.
For the FAO report “The Impact of Disasters on Agriculture and Food Security 2023 – Avoiding and reducing losses through investment in resilience“, the scientists developed a methodology that combines factual and counterfactual large-ensemble climate model data with statistical yield modelling. The approach links greenhouse gas emissions to climate and extreme weather events to observed crop yields. This makes it possible to derive attribution statements both for overall yield levels recorded over the last twenty years and those in particularly low-yielding years that have substantial economic, cultural, or food security consequences. The scientists show that by quantifying the degree to which human and natural systems are already influenced by anthropogenic climate change, climate impact attribution science offers an entry point for assessing losses and damages from climate change (extreme events and slow-onset changes).
In the report, the methodology is applied to four case studies across the world. The authors find that in three out of the four cases considered, climate change has had a detrimental effect, both on mean yields, and even more so on particularly low yields. Specifically, it was estimated that climate change has made average yields during 2000-2019 for maize in South Africa and wheat in Kazakhstan as well as Morocco lower by about 0.1-0.2 tons per hectare in each case, amounting to around 5%,10%, and 2%, respectively. Climate change impacts on the low yield levels of the respective disaster years 2010, 2019, and 2007 were estimated to have been even stronger, making them about 10, 2.5, and slightly more likely, respectively. In contrast, it was found that climate change has made average soy yields in Argentina during 2000-2019 slightly higher and the low soy yield levels of 2018 about half as likely. The numbers show quite a wide range depending on crop type and country.
Going forward, the authors stress the importance of comprehensive uncertainty quantification and highlight that the methodology can easily be linked with further modelling steps to quantify both non-economic and economic losses and damages from climate change related to agricultural production. This may be relevant for the ongoing international debate on Loss and Damage and, if the methodology is applied to future climate projections as opposed to the counterfactual past, the results can also inform adaptation and comprehensive disaster risk management.
The FAO’s report altogether shows that climate change to date, detrimental weather and climate even where still indistinguishable from natural variability, and other drivers such as pandemics or armed conflict, compound to cause disasters. Together, disasters are estimated to have caused losses of an estimated USD 3.8 trillion in crops and livestock over the last 30 years, equivalent to 5%of annual global agricultural GDP, with the highest relative losses in lower- and lower-middle-income countries and at insufferable humanitarian costs, calling for investments in proactive and timely interventions. The contribution specifically of climate change to the crop yield levels associated with disasters as shown by the PIK authors spotlight the role of climate change mitigation in reducing future losses and damages, call for implementing adaptation measures, and suggest the urgent need for the international community to agree on ways to deal with unavoided climate change losses and damages.
PIK Director Johan Rockström will be presenting the results of this report with the FAO in a side-event of COP today (on the 01.12.2023), a live stream and recording of which is available here. More information on PIK-presence at COP28 can be found here
Undorf, S., L. Jansen, P. Romanovska, B. Schauberger, and C. Gornott (2023). Attribution of the impacts of climate change on agriculture caused by extreme events and concurring other climatic influences. In: The Impact of Disasters on Agriculture and Food Security 2023 – Avoiding and reducing losses through investment in resilience. Flagship report by the FAO, Rome, https://www.fao.org/documents/card/en/c/cc7900en, pp 60-65.
