EGU23-12826, updated on 26 Feb 2023
https://doi.org/10.5194/egusphere-egu23-12826
EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Coastal winds in the Gulf of Cádiz (southwestern Iberian Peninsula): insights from observations and models

Carlos Román-Cascón1, Tina Brnas1, Pablo Ortiz-Corral2, Gert-Jan Steeneveld3, Águeda Vázquez1, Miguel Bruno1, Alfredo Izquierdo1, Julio Reyes1, Jeanette Romero1, José Antonio Adame4, Jielun Sun5, and Carlos Yagüe2
Carlos Román-Cascón et al.
  • 1Department of Applied Physics. University of Cadiz. CASEM, 11510 Puerto Real, Cadiz, Spain
  • 2Departamento de Física de la Tierra y Astrofísica. Universidad Complutense de Madrid. 28040 Madrid, Spain
  • 3Meteorology and Air Quality (MAQ) Section. Wageningen University. Wageningen, The Netherlands
  • 4Atmospheric Sounding Station, El Arenosillo observatory. National Institute for Aerospace Technology. 21130 Mazagón, Huelva, Spain
  • 5NorthWest Research Associates, Boulder, CO, USA

Winds in coastal areas are particularly complex due to the drastic change of roughness and thermal properties between the sea and the land areas. Besides, the coastal topography, the shoreline irregularities, the surface state (land cover/use, soil moisture, sea surface temperature (SST), wind waves), and the interactions with the upper parts of the atmospheric boundary layer (ABL) add more complexity to the final characteristics of the surface winds of these regions.

Among coastal winds, coastal breezes are especially common thermally driven flows formed in mid-latitude regions under fair-weather synoptic conditions. Under these situations, the thermal gradient between the sea and the ocean becomes more important, generating pressure gradient forces that lead to onshore winds during the daytime and offshore during the night. The impacts of these winds are broad and varied: they transport humidity, pollutants, and other physical properties in these regions; they can initiate convection (and even trigger the formation of storms), and they also drive the surface coastal currents, among others. From a societal point of view, the coastal breezes are crucial for the wind power industry, air-quality forecasts, maritime sports, and simply for the refreshing impact they cause, an aspect especially important in some areas commonly affected by extreme maximum temperatures and heat waves. Therefore, a correct understanding of the physical characteristics of the coastal breezes is a needed step to correctly forecast them and to be able to investigate their future trends.

In this work, we present an observational analysis of the coastal breezes observed in the Gulf of Cádiz. We highlight some differences found between the breezes formed at the sea and at the land areas from observational measurements. Besides, we use the mesoscale Weather Research and Forecasting (WRF) model to simulate key case studies, showing how the interaction with the background synoptic wind is very important for the final characteristics that the breezes have. Related to this, we have observed how the effect of the changes in the surface (SST, soil moisture) on the breeze’s characteristics depend on the wind vertical profile (background wind). That is, surface changes impact the ABL mixing and the momentum transfer from higher levels, which seems to be the main mechanism that impact the breezes at lower levels, even more than the surface thermal gradient effect.

How to cite: Román-Cascón, C., Brnas, T., Ortiz-Corral, P., Steeneveld, G.-J., Vázquez, Á., Bruno, M., Izquierdo, A., Reyes, J., Romero, J., Adame, J. A., Sun, J., and Yagüe, C.: Coastal winds in the Gulf of Cádiz (southwestern Iberian Peninsula): insights from observations and models, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-12826, https://doi.org/10.5194/egusphere-egu23-12826, 2023.