Moisture recycling and vulnerability of Congo's peatlands

Located in the Congo River basin, the Cuvette Centrale is a densely forested peatland containing billions of tons of carbon. Past work has shown that this peatland is susceptible to large-scale drying trends, which could lead to substantial carbon release to the atmosphere. Understanding the sources of atmospheric water that sustain the Cuvette Centrale, as well as changes to these sources, is essential for characterizing current and future vulnerability. In this presentation, I will share recent work that examines the sources of moisture for the Cuvette Centrale over the first two decades of the 21st century. The results indicate that a substantial fraction of mean annual precipitation falling in the Cuvette Centrale arises as both local evaporation and evaporation from elsewhere in the Congo Basin. An analysis of annual anomalies reveals a multi-decadal drying trend occurring in the Cuvette Centrale, which may be associated with changes occurring throughout key evaporation source areas. Likewise, important links are shown between key ecohydrologic dynamics and moisture recycling to the Cuvette Centrale, such as changes in upwind evaporative stress. This work provides an approach for examining and interpreting changing hydroclimatic vulnerability of critical, global carbon stocks, such as in tropical peatlands. Furthermore, this work underlines the importance of monitoring land-surface changes that could affect moisture recycling to the Cuvette Centrale, such as expanding deforestation across the Congo Basin.