Impact of Extreme Future Climate on Aerosol Formation
CHRISTIAN MARK SALVADOR, Jonathan Stelling, Mark Guilliams, Kyle Pearson, Meng-Dawn Cheng, Paul Hanson, Oak Ridge National Laboratory
Abstract Number: 336
Working Group: Aerosol Processes and Properties in Changing Environments in the Anthropocene
Abstract
Extreme future climate conditions are expected to create unprecedented changes in aerosol formation, leading to feedback mechanisms that will affect atmospheric warming, agriculture, and sea surface temperatures. Atmospheric particles play a crucial role in the Earth's radiative budget by directly scattering solar radiation and indirectly acting as nuclei for cloud formation. While several studies have investigated the impacts of temperature and carbon dioxide (CO2), direct observational evidence of aerosol formation in real environmental conditions, specifically under extreme climate scenarios such as 900 ppm CO2 and temperature increases of 4.5 to 9.0°C above ambient levels—remains scarce. This gap in knowledge results in significant uncertainties in global earth system models that evaluate aerosol-cloud-climate interactions. In this study, we analyzed particle size and distribution during aerosol formation events, as well as their frequency and growth rates in a boreal forest, a region predicted to be particularly sensitive to climate change and warming more rapidly. Our research was conducted at the Spruce and Peatland Responses Under Changing Environments (SPRUCE) site at the Oak Ridge National Laboratory (ORNL), which features modified open-top chambers designed for precise ecosystem warming, both above and below ground, along with capabilities for elevated CO2 enrichment. We conducted concurrent measurements of real-time particle counts and sizes using the NanoScan SMPS Nanoparticle Sizer 3910 across different conditions: ambient (control, Plot 6), elevated temperature (+9°C, Plot 17), and enhanced CO2 concentration (~900 ppm, Plot 19). The results and atmospheric implication from these field campaigns will be discussed in the presentation.