Central California Ozone Study (CCOS) - Desert Research Institute

CCOS Field Operations Plan Version 2: 5/31/00
• Flux plane estimation of transport - model evaluation and corroborative transport
assessment.
• Reconciliation of aloft data with the conceptual model.
Specific objectives of the aircraft flights during CCOS are to collect data pertinent to the
following chemical and meteorological conditions and processes.
1. Boundary conditions along western edge of the modeling domain.
2. Ozone and precursor fluxes into Livermore Valley
3. Ozone and precursor fluxes from Carquinez Strait, Altamont Pass and Pacheco Pass into
Central Valley.
4. Transport of ozone and precursors to Sacramento and upper Sacramento Valley.
5. Transport of ozone and precursors within San Joaquin Valley via low-level jet plus
circulation.
6. Intra-valley transport within the San Joaquin Valley by eddies and slope-flows.
7. Boundary condition along northern edge of the modeling domain.
8. Outflow of ozone and precursors from the San Joaquin Valley into San Louis Obispo
County.
9. Outflow of ozone and precursors from the San Joaquin Valley into the southeast Desert.
10. Ozone layer aloft and interaction with surface.
11. Transport of pollutants in the nocturnal low-level jet.
12. Northern SLO Co. at Paso Robles transport impact from the San Francisco Bay area
and/or SJV.
In order to quantify pollutant transport and to provide data for modeling and data
analyses, surface and aloft measurements are needed at locations where transport can occur and
at the times when transport is occurring. These monitoring locations include in and near
mountain passes, along coastlines, offshore, and at various locations in the downwind air basin.
Aloft measurements made by instrumented aircraft will be used to calculate transport across flux
planes. Vertical planes, intersecting the profiler sites downwind of and perpendicular to the
transport path, can be defined and provide estimates of transport through these passes using
surface and aircraft measurements of pollutant concentrations and surface and wind profiler data
for volume flux estimations.
Four instrumented aircraft will be used to measure the vertical and horizontal gradients of
ozone, NOx, ROG, temperature, and humidity in the study region during CCOS IOPs. These
Chapter 2: FIELD MEASUREMENTS 2-45