Oceans as a source of airborne metabolites and primary biological aerosol particles
EMSL Project ID
50203
Abstract
Ocean waters, which cover 71% of the Earth's surface, contain dissolved organic carbon (DOC) including lipids, humics and organic acids, and free macromolecules, the precursor material for the formation of nano- to micro-sized polysaccharidic and proteinaceous containing particles including transparent exopolymer particles (TEP). These dissolved organic molecules and compounds are formed through the activities of planktonic microorganisms which also generate primary biological aerosol particles (PBAPs) which can include cells and their fragments. DOC and PBAPs can become airborne by waves breaking and bubbles bursting at the sea surface. We propose a combination of laboratory and field studies to resolve the physicochemical properties and molecular speciation, and track metabolomic signatures of these airborne biogenic matter and biological particles in relation to the composition of the surface waters. Mesocosm experiments with controlled growth of cosmopolitan phyto- and bacterioplankton simulating ocean waters will use bubble bursting, to aerosolize particles for chemical analyses while monitoring the biochemical evolution of the subsurface and surface microlayer (SML). Aerosol particles generated during experiments will be accompanied by the investigation of particles collected in a marine environment on a remote ocean island during the DOE sponsored Aerosol and Cloud Experiments in Eastern North Atlantic (ACE-ENA). The dominant source of particles in the marine boundary layer of this Azores site is the surrounding ocean waters. Our goal is to address the following questions: i) What is the abundance of marine biogenic matter including metabolites (e.g., lipids, amino acids, organic acids), TEP and PBAPs in ocean surface waters and airborne material? ii) Are the chemical characteristics and the metabolomic signatures of airborne biogenic matter different from the ones in the ocean surface waters? iii) Can laboratory derived particles reproduce the unique chemical fingerprints of metabolic processes as naturally occurring aerosol particles at the near aquatic surface? EMSL/PNNL provides unique micro-spectroscopic single particle analytical techniques and high-resolution mass spectrometric techniques to examine the physicochemical characteristics of aerosols in the nm-to-micro-m size range and resolve associated molecular signatures in the particulate phase and ocean waters. The proposed research activities to examine the physicochemical properties of marine microbially derived aerosol particles directly addresses DOE BER's mission to "achieve fundamental understanding and prediction of complex biological, Earth, and environmental systems" and are in direct response to the EMSL Science Theme "Environmental Sciences Area" that focuses on the investigation of "the molecular composition and formation of aerosols near the land or aquatic surface, and their dynamics/evolution in the very near Earth surface". This project combines the expertise of the School of Marine and Atmospheric Sciences at Stony Brook University with the unique user facilities at EMSL to address ocean-atmosphere interactions. Relevant EMSL instruments to examine the microstructure and chemical characteristics of particles and ocean waters include FIB/SEM-EDX, TEM, LTQ-Orbitrap MS with nano-DESI, LC-MS Orbitrap, and 21T FTICR MS. Application of these techniques is crucial for a significant advance in this research area.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2018-10-01
End Date
2019-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)
Team Members