Boundary-Layer Meteorology

, Volume 158, Issue 2, pp 311–330

Characterization of the Marine Boundary Layer and the Trade-Wind Inversion over the Sub-tropical North Atlantic

  • J. Carrillo
  • J. C. Guerra
  • E. Cuevas
  • J. Barrancos
Article

DOI: 10.1007/s10546-015-0081-1

Cite this article as:
Carrillo, J., Guerra, J.C., Cuevas, E. et al. Boundary-Layer Meteorol (2016) 158: 311. doi:10.1007/s10546-015-0081-1

Abstract

The stability of the lower troposphere along the east side of the sub-tropical North Atlantic is analyzed and characterized using upper air meteorological long-term records at the Canary Islands (Tenerife), Madeira (Madeira) and Azores (Terceira) archipelagos. The most remarkable characteristic is the strong stratification observed in the lower troposphere, with a strengthening of stability centred at levels near 900 and 800 hPa in a significant percentage of soundings (ranging from 17 % in Azores to 33 % in Güimar, Canary Islands). We show that this double structure is associated with the top of the marine boundary layer (MBL) and the trade-wind inversion (TWI) respectively. The top of the MBL coincides with the base of the first temperature inversion (\(\approx \)900 hPa) where a sharp change in water vapour mixing ratio is observed. A second temperature inversion is found near 800 hPa, which is characterized by a large directional wind shear just above the inversion layer, tied to the TWI. We find that seasonal and latitudinal variations of the height and strength of both temperature inversions are driven by large-scale subsiding air from the upper troposphere associated with the descent branch of the Hadley cell. Increased general subsidence in summertime enhances stability in the lower troposphere, more markedly in the southern stations, where the inversion-layer heights are found at lower levels enhancing the main features of these two temperature inversions. A simple conceptual model that explains the lower tropospheric inversion enhancement by subsidence is proposed.

Keywords

Marine boundary layer Radiosondes Subsidence  Sub-tropical troposphere Temperature inversion Trade-wind inversion 

Supplementary material

10546_2015_81_MOESM1_ESM.docx (12 kb)
S1 Statistical comparison of temperature series at three pressure levels between Santa Cruz (1997-2001) and Güimar (2003-2007). Results of Kolmógorov–Smirnov and Mann-Whitney nonparametric tests. (Doc 13 KB)
10546_2015_81_MOESM2_ESM.docx (14 kb)
S2 Percentage of superadiabatic lapse rate (% SA) and fictitious inversion layers (% F). (Doc 15 KB)
10546_2015_81_MOESM3_ESM.docx (12 kb)
S3 Number and percentage of soundings in which the number of simultaneous inversions ʽNIʼ is zero, one, two, or more than two, within the 1000-700 hPa range, at each station. (Doc 13 KB)
10546_2015_81_MOESM4_ESM.ps (173 kb)
S4 Base height of MBL inversion (MBLI) (*) and trade-wind inversion (TWI) (□) vs vertical velocity (hPa s-1) in the 700-hPa range, as in Fig. 5 (right) at Azores, Madeira and Canary Islands (Güimar). (ps 173 KB)

Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  • J. Carrillo
    • 2
  • J. C. Guerra
    • 2
  • E. Cuevas
    • 1
    • 2
  • J. Barrancos
    • 3
  1. 1.Izaña Atmospheric Research Centre (IARC)Agencia Estatal de Meteorología (AEMET)Santa Cruz de TenerifeSpain
  2. 2.Hydrometeorology Research Group (GRIHM)La Laguna University (ULL)Santa Cruz de TenerifeSpain
  3. 3.Environmental Research DivisionInstituto Tecnológico de Energías Renovables (ITER)Granadilla de AbonaSpain

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