Long-term isoprene (BVOC) fluxes in the Amazon Rainflorest by relaxed eddy accumulation coupled to GC/PID (REAPER)

Abstract

Understanding the role of Biogenic Volatile Organic Compounds (BVOCs) in atmospheric chemistry and their impact on oxidants and aerosol formation is essential for global environmental research. BVOC emissions, primarily sourced from biogenic processes, pose a challenge due to the vast diversity of vegetation and ecosystems, as well as temporal changes in land use. While prevalent BVOC emission models categorize vegetation into functional types, the variability in environmental parameters and temporal fluctuations within natural canopies remains inadequately represented. This study introduces an innovative device system designed to address these challenges by integrating the Relaxed Eddy Accumulator and Gas Chromatograph Photoionization Detector (REAPER) in real-time measurement of isoprene fluxes. The system is portable, cost-effective and lightweight, easily to deploy in remote environments. By enabling high temporal resolution measurements, this device overcomes limitations associated with traditional techniques and offers accurate chromatograms. The novel instrument also facilitates real-time data transmission through a cloud-based platform, allowing access to meteorological data, calculated parameters, chromatograms and flux results. This feature supports the deployment of these systems across a wide range of sites and integrates them into existing flux tower networks. In conclusion, this research contributes to the advancement of isoprene fluxes measurement techniques and validation of satellite-based retrievals of isoprene abundances providing a valuable tool for scientists studying atmospheric chemistry and its impacts on the environment in diverse ecosystems, ultimately aiding in our understanding of the complex interplay between biogenic processes and atmospheric chemistry. The REAPER is installed in the ATTO tower in the Amazon rainforest and continuously measures Isoprene every hour within parts per billion (ppb) content. All the meteorology and chemistry data are sent through the Internet anywhere in the world to measure the BVOCs fluxes.