Author(s)

Hugo Abi Karam¹, Jorge Fernando Soares Gonçalves², Augusto José Pereira Filho³

¹Departamento de Meteorologia, Instituto de Geociências, Universidade Federal do Rio de Janeiro (IGEO-UFRJ), Rio de Janeiro, Brazil.
²IBERMETEO, Coimbra, Portugal.
³Departamento de Ciências Atmosféricas, Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo (IAG-USP), São Paulo, Brazil.

In this work, it is investigated the Urban Heat Island (UHI) using conservative thermodynamic variables observed by surface weather stations on the Metropolitan Area of Porto (Oporto) in Portugal, under adiabatic conditions at the surface. These conditions are usually present and associated with the development of a mixture layer into the diurnal Convective Boundary Layer (CBL), which residual layer in the late afternoon defines the initial state for the development of the nocturnal UHI. Both the spatial structure and temporal variation of potential temperature and specific humidity were considered, along the hours and days of the year, from a statistical point of view, resulting in hourly climatology. Details of the hourly evolution of the meteorological variables on the Oporto surface are presented and discussed. Results show a seasonal variation of the potential temperature up to 17°C throughout the year, which is associated with horizontal thermal gradients that can control and trigger mesoscale circulations such as sea-land, urban and valley-mountain breezes.

Metropolitan Area of Porto (Oporto) Climatology, Urban Heat Island Development, Urban Boundary Layer, Mesoscale Atmospheric Circulations

Karam, H. , Gonçalves, J. and Filho, A. (2022) Diurnal Cycle of Heating and Water Vapor in the Metropolitan Area of Porto in Portugal. Journal of Geographic Information System, 14, 61-77. doi: 10.4236/jgis.2022.141004.