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I. González-Aparicio J. Hidalgo A. Baklanov U. Korsholm R. Nuterman A. Mahura O. Santa-Coloma 《Theoretical and Applied Climatology》2013,113(3-4):511-527
This study analyses the atmospheric boundary layer over the Bilbao metropolitan area during summer (13–18 Jul 2009) and winter (20–29 Jan 2010) episodes using the Environment–High Resolution Limited Area Model (Enviro-HIRLAM) coupled with the building effect parameterisation (BEP). The main objectives of this study are: to evaluate the performance of the model to simulate the land–sea breezes over this complex terrain; to assess the simulations with the integration of an urban parameterisation in Enviro-HIRLAM and finally; and to analyse the urban–atmosphere interactions. Even if the hydrostraticity of the model is a limitation to simulate atmospheric flows over complex terrain, sensibility tests demonstrate that 2.4 km is the optimal horizontal resolution over Bilbao that allows at the same time: to obtain satisfactory reproducibility of the large-scale processes and to explore the urban effects at local scale. During the summer episode, a typical regime of diurnal sea breeze from the NW-N-NE direction and nocturnal valley breezes from the SE direction are observed over Bilbao. The urban heat island (UHI) phenomenon is developed in the city centre expanding to the suburbs from 22 to 10 local time (LT), covering an area of 130 km2. The maximum UHI intensity, 1 °C, is reached at the end of the night (5 LT), and it is advected 12 km towards the sea by the land breezes. The urban boundary layer (UBL) height amplitude varies from 100 (night time) to 1,360 m (at 14 LT). During the winter episode, the land breeze dominates the atmospheric diffusion during the day and night time. The maximum UHI intensity, 1.7 °C, is observed at 01 LT. It is spread and remained over the city covering an area of 160 km2, with a vertical extension of 33 m. The UBL reaches 780 m height at 16 LT the following day. 相似文献
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Penenko Vladimir Baklanov Alexander Tsvetova Elena Mahura Alexander 《Pure and Applied Geophysics》2012,169(3):447-465
A concept of environmental forecasting based on a variational approach is discussed. The basic idea is to augment the existing
technology of modeling by a combination of direct and inverse methods. By this means, the scope of environmental studies can
be substantially enlarged. In the concept, mathematical models of processes and observation data subject to some uncertainties
are considered. The modeling system is derived from a specially formulated weak-constraint variational principle. A set of
algorithms for implementing the concept is presented. These are: algorithms for the solution of direct, adjoint, and inverse
problems; adjoint sensitivity algorithms; data assimilation procedures; etc. Methods of quantitative estimations of uncertainty
are of particular interest since uncertainty functions play a fundamental role for data assimilation, assessment of model
quality, and inverse problem solving. A scenario approach is an essential part of the concept. Some methods of orthogonal
decomposition of multi-dimensional phase spaces are used to reconstruct the hydrodynamic background fields from available
data and to include climatic data into long-term prognostic scenarios. Subspaces with informative bases are constructed to
use in deterministic or stochastic-deterministic scenarios for forecasting air quality and risk assessment. The results of
implementing example scenarios for the Siberian regions are presented. 相似文献
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