R/V Ronald H. Brown Sampling Strategy
The instrumentation deployed on the NOAA R/V Ronald H. Brown allows the characterization of a wide range of gaseous and particulate pollution. This was accomplished primarily through fast-response in situ sampling augmented with the ozone/aerosol profiling capability of the DIAL lidar. The lidar was particularly important when sampling in a stable marine boundary layer as it provided a vertical context for the ship-board measurements.
The sampling cruise provided insight into the processes that control the high pollution episodes along the coast of New England, and focused on three major scientific objectives:
- Characterization of Sources - It is important to characterize the mix of emissions that impact the region whether they come from sources within or outside the region. To meet this objective a number of near-shore survey tracks were made under conditions when the polluted continental air was expected to transport into the surface marine layer (i.e. nighttime, early morning, late day)
- Study of Transport and Transformation Processes - The marine environment is unique both in terms of the dynamics (mixing and transport) and chemistry. Although a great deal is known about the transport and chemistry of polluted air masses and plumes over land very little is known about the processing that occurs in the marine environment. The compliment of instruments on-board the ship will be used to document the evolution of polluted air masses in the Gulf of Maine during the entire diurnal cycle.
- Study of Coastal Impacts - The impact of polluted air masses transported over the Gulf of Maine is evident in the ozone monitoring record for the region. It has been hypothesized that the complex dynamics of the sea-breeze/land-breeze circuit (SBLB) plays a major role in transporting polluted air off the Gulf of Maine into coastal New England. To address this objective the ship was deployed near the heavily instrumented region along the New Hampshire coast in a coordinated study of the SBLB.