Presentation is loading. Please wait.

Presentation is loading. Please wait.

3: L model evaluation: Łódź (2001-02) & Baltimore (2002-06) (Loridan et al. 2010) 2: A simple parameterization of incoming longwave radiation (Loridan.

Similar presentations


Presentation on theme: "3: L model evaluation: Łódź (2001-02) & Baltimore (2002-06) (Loridan et al. 2010) 2: A simple parameterization of incoming longwave radiation (Loridan."— Presentation transcript:

1 3: L model evaluation: Łódź (2001-02) & Baltimore (2002-06) (Loridan et al. 2010) 2: A simple parameterization of incoming longwave radiation (Loridan et al. 2010) 2.1: Background 2.2: Cloud fraction estimate from ceilometer data at Kings College London Urban Meteorology Group, Kings College London http://geography.kcl.ac.uk/micromet/index.htm Contact: thomas.loridan@kcl.ac.uk Introduction Local-scale Urban Meteorological Parameterization Scheme (LUMPS, Grimmond and Oke 2002), a simple model to simulate the heat fluxes from the urban environment, that only requires easily obtained meteorological variables and surface characteristics. Objectives: (1) Parameterization of incoming longwave radiation is revisited using cloud data from the Kings College London urban field site (2) Performance of LUMPS is evaluated using independent data from the Łódź field campaign (Offerle et al., 2006) 1: Overview of LUMPS Thomas Loridan*, Sue Grimmond*, Brian D. Offerle**, Duick T. Young*, Thomas E. L. Smith*, Leena Järvi* and Fredrik Lindberg* *Kings College London, Department of Geography, London, UK, ** FluxSense, Goteborg, Sweden University of Helsinki, Department of Physics, Helsinki, Finland References Crawford, B., C.S.B. Grimmond, J. Hom, and A. Christen, 2010: Carbon dioxide fluxes in suburban Baltimore: 2002 – 2006. (in preparation) Grimmond, C. S. B., and T. R. Oke, 2002: Turbulent heat fluxes in urban areas: observations and a local-scale urban meteorological parameterization scheme (LUMPS). Journal of Applied Meteorology 41: 792–810. Loridan, T., C. S. B. Grimmond, B. Offerle, D. T. Young, T. E. L. Smith, L. Järvi, and F. Lindberg, 2010: Local-Scale Urban Meteorological Parameterization Scheme (LUMPS): longwave radiation parameterization and seasonality related developments. Journal of Applied Meteorology. (submitted) Offerle, B., C. S. B. Grimmond, and T. R. Oke, 2003: Parameterization of net all-wave radiation for urban areas. Journal of Applied Meteorology 42: 1157–1173. Offerle, B., C. S. B. Grimmond, K. Fortuniak, K. Klysik, and T. R. Oke, 2006: Temporal variations in heat fluxes over a central European city centre. Theoretical and applied climatology 84: 103-116. Acknowledgments Thanks to all those who were involved in the Baltimore, Łódź and London field campaigns, especially Krzysztof Fortuniak, Alastair Reynolds, and Steve Scott. Financial support for this project for the fieldwork and the analyses was provided to Grimmond by the U. S. National Science Foundation (ATM-0710631, BCS-0221105, BCS-0095284), EU (FP7-ENV-2007-1 211345) Bridge, USDA Forest Service (CA-11242343-082; 04-CA-11242343-124; 05-CA-11242343-11), and Kings College London. The LUMPS model is available at: http://geography.kcl.ac.uk/micromet/index.htm Sub- model Inputs and parametersParameterization scheme NARP (Offerle et al. 2003) K (from measurements) L (measured or modelled) T a : air temperature (measured) α 0, ε 0 : bulk surface albedo and emissivity OHM Q* (from NARP, eq. 1) a 1i, a 2i, a 3i : OHM surface characteristics f i : fraction area cover Q H / Q E partitioning scheme Q* (from NARP, eq. 1) ΔQ S (from OHM, eq. 2) s: slope of the saturation vapour pressure- temperature curve (Pa K -1 ) γ: psychrometric constant (Pa K -1 ) α, β: partitioning coefficients (depends on surface cover, Table 4) LUMPS simulates the surface energy balance (SEB) fluxes in a succession of sub-models (Fig. 1, Table 1): [SEB]Q* (+Q F ) = Q H + Q E + Q S where Q* net all-wave radiation and consists of: Q* = K - K + L - L where K (K) incoming (outgoing) shortwave radiation L (L) incoming (outgoing) longwave radiation Q F anthropogenic heat flux (not explicitly modelled) Q H turbulent sensible heat Q E turbulent latent heat flux Q S net heat storage flux TheoryParameterizationNotation L considered to be emitted by a single-layer atmosphere (Stefan-Boltzmann law) (4) ε sky : Sky emissivity T sky : Bulk sky temperature (K) σ: Stefans constant (W m -2 K -4 ) Clear sky emissivity (ε clear ): approximated from Prata (1996) using commonly measured meteorological quantities (5) ε clear : Clear sky emissivity w: precipitable water content (g cm -2 ) T a : measured air temperature (K) e a : measured vapour pressure (hPa) Impact of clouds on L: all sky emissivity (ε sky ) derived from an estimation of cloud fraction (F CLD ) T sky is approximated by T a (6) F CLD : Cloud fraction (0 { "@context": "http://schema.org", "@type": "ImageObject", "contentUrl": "http://images.slideplayer.com/3/799743/slides/slide_1.jpg", "name": "3: L model evaluation: Łódź (2001-02) & Baltimore (2002-06) (Loridan et al.", "description": "2010) 2: A simple parameterization of incoming longwave radiation (Loridan et al. 2010) 2.1: Background 2.2: Cloud fraction estimate from ceilometer data at Kings College London Urban Meteorology Group, Kings College London http://geography.kcl.ac.uk/micromet/index.htm Contact: thomas.loridan@kcl.ac.uk Introduction Local-scale Urban Meteorological Parameterization Scheme (LUMPS, Grimmond and Oke 2002), a simple model to simulate the heat fluxes from the urban environment, that only requires easily obtained meteorological variables and surface characteristics. Objectives: (1) Parameterization of incoming longwave radiation is revisited using cloud data from the Kings College London urban field site (2) Performance of LUMPS is evaluated using independent data from the Łódź field campaign (Offerle et al., 2006) 1: Overview of LUMPS Thomas Loridan*, Sue Grimmond*, Brian D. Offerle**, Duick T. Young*, Thomas E. L. Smith*, Leena Järvi* and Fredrik Lindberg* *Kings College London, Department of Geography, London, UK, ** FluxSense, Goteborg, Sweden University of Helsinki, Department of Physics, Helsinki, Finland References Crawford, B., C.S.B. Grimmond, J. Hom, and A. Christen, 2010: Carbon dioxide fluxes in suburban Baltimore: 2002 – 2006. (in preparation) Grimmond, C. S. B., and T. R. Oke, 2002: Turbulent heat fluxes in urban areas: observations and a local-scale urban meteorological parameterization scheme (LUMPS). Journal of Applied Meteorology 41: 792–810. Loridan, T., C. S. B. Grimmond, B. Offerle, D. T. Young, T. E. L. Smith, L. Järvi, and F. Lindberg, 2010: Local-Scale Urban Meteorological Parameterization Scheme (LUMPS): longwave radiation parameterization and seasonality related developments. Journal of Applied Meteorology. (submitted) Offerle, B., C. S. B. Grimmond, and T. R. Oke, 2003: Parameterization of net all-wave radiation for urban areas. Journal of Applied Meteorology 42: 1157–1173. Offerle, B., C. S. B. Grimmond, K. Fortuniak, K. Klysik, and T. R. Oke, 2006: Temporal variations in heat fluxes over a central European city centre. Theoretical and applied climatology 84: 103-116. Acknowledgments Thanks to all those who were involved in the Baltimore, Łódź and London field campaigns, especially Krzysztof Fortuniak, Alastair Reynolds, and Steve Scott. Financial support for this project for the fieldwork and the analyses was provided to Grimmond by the U. S. National Science Foundation (ATM-0710631, BCS-0221105, BCS-0095284), EU (FP7-ENV-2007-1 211345) Bridge, USDA Forest Service (CA-11242343-082; 04-CA-11242343-124; 05-CA-11242343-11), and Kings College London. The LUMPS model is available at: http://geography.kcl.ac.uk/micromet/index.htm Sub- model Inputs and parametersParameterization scheme NARP (Offerle et al. 2003) K (from measurements) L (measured or modelled) T a : air temperature (measured) α 0, ε 0 : bulk surface albedo and emissivity OHM Q* (from NARP, eq. 1) a 1i, a 2i, a 3i : OHM surface characteristics f i : fraction area cover Q H / Q E partitioning scheme Q* (from NARP, eq. 1) ΔQ S (from OHM, eq. 2) s: slope of the saturation vapour pressure- temperature curve (Pa K -1 ) γ: psychrometric constant (Pa K -1 ) α, β: partitioning coefficients (depends on surface cover, Table 4) LUMPS simulates the surface energy balance (SEB) fluxes in a succession of sub-models (Fig. 1, Table 1): [SEB]Q* (+Q F ) = Q H + Q E + Q S where Q* net all-wave radiation and consists of: Q* = K - K + L - L where K (K) incoming (outgoing) shortwave radiation L (L) incoming (outgoing) longwave radiation Q F anthropogenic heat flux (not explicitly modelled) Q H turbulent sensible heat Q E turbulent latent heat flux Q S net heat storage flux TheoryParameterizationNotation L considered to be emitted by a single-layer atmosphere (Stefan-Boltzmann law) (4) ε sky : Sky emissivity T sky : Bulk sky temperature (K) σ: Stefans constant (W m -2 K -4 ) Clear sky emissivity (ε clear ): approximated from Prata (1996) using commonly measured meteorological quantities (5) ε clear : Clear sky emissivity w: precipitable water content (g cm -2 ) T a : measured air temperature (K) e a : measured vapour pressure (hPa) Impact of clouds on L: all sky emissivity (ε sky ) derived from an estimation of cloud fraction (F CLD ) T sky is approximated by T a (6) F CLD : Cloud fraction (0


Download ppt "3: L model evaluation: Łódź (2001-02) & Baltimore (2002-06) (Loridan et al. 2010) 2: A simple parameterization of incoming longwave radiation (Loridan."

Similar presentations


Ads by Google