Lidar Objectives

Gulf / bay / land Breeze

The following flows are due to the temperature contrast between land and water, and are most likely to occur when the large-scale weather pattern is stagnant.

Land breeze (LB) Nighttime and early morning winds that flow from the land toward Galveston Bay or the Gulf of Mexico.

Bay breeze (BB) Flow from the direction of Galveston Bay (easterly to southeasterly flow at LaPorte/Houston) that usually begins ~11:00 am. Ozone values often increase rapidly after the onset of the bay breeze, and these higher concentrations of ozone are carried inland by the bay breeze.

Gulf breeze (GB) Onshore flow from the direction of the Gulf of Mexico (southerly flow) that appears after the bay breeze has formed.

Ship channel-induced flows (SC) Small-scale circulations associated with the ship channel that bring pollutants from the ship channel to nearby surrounding areas.

For these flows, we will investigate:

  • Transitions between onshore and offshore flows
  • Convergence zone between onshore and offshore flow
  • Horizontal variability of the bay and gulf breezes
  • Changes with height of the wind speed, wind direction, and the aerosol content of the air
  • Merging of the bay and gulf breezes

Understanding the role of these breezes in the transport of ozone can be achieved by comparing measurements from the TEA CO2 Doppler lidar and OPAL.

  • What changes do we see in OPAL ozone measurements that coincide with the front passages, the merging of the bay and gulf breezes, and wind shifts with height?

Other features of interest to document with the TEA CO2 Doppler lidar:

  • Propagation of the bay breeze over the ship channel
  • How distinct are the bay breeze and gulf breeze fronts?
  • Are the return flows for the bay and gulf breezes detectable?
  • Can the Doppler lidar detect the ship channel circulations?
  • Thunderstorm gust fronts redistribute ozone and increase the difficulty of ozone forecasting. If a gust front does propagate across the LaPorte Airport ground site, we can measure changes in the winds and ozone concentrations associated with it.
  • Stagnation point due to divergence over Galveston Bay. The lidar probably will not have the range to detect this, but it is something we can look for.