Heat Flux on Mixtures of Different Land-use Surface: Test of a New Parameterization Scheme

Kimura, Fujio

doi:10.2151/jmsj1965.67.3_401

Cited by 32 publications

(7 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 3a illustrates the distribution of the urban ratio in 1997 (period II). The surface heat and moisture fluxes are calculated on the basis of the tiles of both the urban and vegetative structures, and then these fluxes in a grid cell are given by the weighted averages of the fluxes from the two subgrid tiles according to the urban ratio (Kimura 1989). Surface parameters for urban and vegetation areas are summarized in Table 3.…”

Section: Land-use and Anthropogenic Heat Datamentioning

confidence: 99%

Comparison of the Impact of Global Climate Changes and Urbanization on Summertime Future Climate in the Tokyo Metropolitan Area

Adachi¹,

Kimura²,

Kusaka³

et al. 2012

Journal of Applied Meteorology and Climatology

Self Cite

View full text Add to dashboard Cite

In this study, the impact of global climate change and anticipated urbanization over the next 70 years is estimated with regard to the summertime local climate in the Tokyo metropolitan area (TMA), whose population is already near its peak now. First, five climate projections for the 2070s calculated with the aid of general circulation models (GCMs) are used for dynamical downscaling experiments to evaluate the impact of global climate changes using a regional climate model. Second, the sensitivity of future urbanization until the 2070s is examined assuming a simple developing urban scenario for the TMA. These two sensitivity analyses indicate that the increase in the surface air temperature from the 1990s to the 2070s is about 2.08C as a result of global climate changes under the A1B scenario in the Intergovernmental Panel on Climate Change's Special Report on Emissions Scenarios (SRES) and about 0.58C as a result of urbanization. Considering the current urban heat island intensity (UHII) of 1.08C, the possible UHII in the future reaches an average of 1.58C in the TMA. This means that the mitigation of the UHII should be one of the ways to adapt to a local temperature increase caused by changes in the future global climate. In addition, the estimation of temperature increase due to global climate change has an uncertainty of about 2.08C depending on the GCM projection, suggesting that the local climate should be projected on the basis of multiple GCM projections.

show abstract

Section: Land-use and Anthropogenic Heat Datamentioning

confidence: 99%

Comparison of the Impact of Global Climate Changes and Urbanization on Summertime Future Climate in the Tokyo Metropolitan Area

Adachi¹,

Kimura²,

Kusaka³

et al. 2012

Journal of Applied Meteorology and Climatology

Self Cite

View full text Add to dashboard Cite

show abstract

“…Then, total fluxes from the model grid are calculated using a sub-grid parameterization for heterogeneous surfaces, as proposed by Kimura (1989). (For more details on the coupled Noah-LSM and UCM system, see Chen et al (2011).)…”

Section: Miao Et Al (2009)mentioning

confidence: 99%

Numerical Simulation of Urban Heat Island Effect by the WRF Model with 4-km Grid Increment: An Inter-Comparison Study between the Urban Canopy Model and Slab Model

Kusaka

Chen

Tewari

et al. 2012

Journal of the Meteorological Society of Japan

View full text Add to dashboard Cite

The present study applies the WRF model involving the single-layer urban canopy model (hereafter, WRF_UCM) to urban climate simulation of the Tokyo metropolitan area for August (2004)(2005)(2006)(2007) and compare results to (a) observations, and (b) the WRF model involving the slab urban model (hereafter, WRF_SLAB). In this urban area, WRF_UCM accurately captures the observed monthly mean daytime and nocturnal UHI, whereas WRF_SLAB does not show a nocturnal UHI. Moreover, the observed diurnal variations of the surface air temperature for central Tokyo and Kumagaya, a nearby inland city, are reproduced well by WRF_UCM. However, WRF_SLAB exhibits both a 1-hr phase shift and a 6.2 C excess oscillation magnitude over observations. In addition, WRF_UCM accurately reproduces the frequency distribution of surface air temperatures, showing a maximum at 27 C, whereas WRF_SLAB produce a bimodal distribution, with double peaks at 23 and 33 C. Finally, WRF_UCM does a much better job than WRF_SLAB at modeling the relative humidity.

show abstract

“…Total heat fluxes from the ground are obtained by the average of the fluxes on each type of ground surface (Kimura 1989). The conductive heat flux G z and interior temperature T z at depth z to each surface are calculated by the one-dimensional thermal conduction equations G z 5 Àl ›T z ›z and (11)…”

Section: A Atmospheric Modelmentioning

confidence: 99%

Proposing the Simplification of the Multilayer Urban Canopy Model: Intercomparison Study of Four Models

Ikeda

Kusaka

2010

Journal of Applied Meteorology and Climatology

View full text Add to dashboard Cite

The study proposes the simplification of the multilayer urban canopy model. Four types of multilayer urban canopy models-level 4, level 3, level 2, and level 1-are developed to reduce the computational load of the heat budget calculations at the wall surface. The level 4 model, which accounts for the wall directions and the vertical layer, is simplified in three ways: the level 3 model only accounts for the vertical layers, the level 2 model accounts for the wall directions, and the level 1 model accounts for neither the wall directions nor the vertical layer. From the simplification, compared to the level 4 model, the memory is reduced by 57%, 65%, and 72% for the level 3-level 1 models, respectively, when the vertical canopy layer is seven. At the same time, the CPU time is reduced by 67%, 70%, and 78% for the level 3-level 1 models. Then, each canopy model is compared with observations in Tokyo. The results show that the simulations from the four models are close to the observed ones, and the differences among the four models are very small. An additional model intercomparison study based on idealized simulations indicates that the level 3 model can be used instead of the level 4 model in any condition, whereas the level 2 and level 1 models are proposed to be used under conditions with a large sky view factor.

show abstract

Heat Flux on Mixtures of Different Land-use Surface: Test of a New Parameterization Scheme

Cited by 32 publications

References 11 publications

Comparison of the Impact of Global Climate Changes and Urbanization on Summertime Future Climate in the Tokyo Metropolitan Area

Comparison of the Impact of Global Climate Changes and Urbanization on Summertime Future Climate in the Tokyo Metropolitan Area

Numerical Simulation of Urban Heat Island Effect by the WRF Model with 4-km Grid Increment: An Inter-Comparison Study between the Urban Canopy Model and Slab Model

Proposing the Simplification of the Multilayer Urban Canopy Model: Intercomparison Study of Four Models

Contact Info

Product

Resources

About