Fig. 1. Domain for Unified Model simulation and study area.
Fig. 2. Surface type fractions of (a, b) broad leaf trees, (c, d) needle leaf trees, (e, f) C3 grass, and (g, h) C4 grass. Left and right panels are derived from the IGBP and EGIS data, respectively (126.6~127.6°E, 37.1~37.8°N).
Fig. 3. Surface type fractions of (a, b) shrubs, (c, d) urban, (c, f) inland water, and (g, h) bare soil. Left and right panels are derived from the IGBP and EGIS data, respectively (126.6~127.6°E, 37.1~37.8°N).
Fig. 4. (a) Scatter plot of IGBP versus EGIS urban land-use fractions and (b) Spatial distribution of the difference between IGBP and EGIS urban land-use fractions with AWS station numbers.
Fig. 6. Spatial distribution of (a) 1.5-m temperature RMSE for CTL, the difference of 1.5-m temperature RMSE between CTL and (b) EXP1, (c) EXP2, and (d) EXP3.
Fig. 7. Spatial distribution of (a) 1.5-m temperature, (b) surface temperature, and (c) sensible heat flux for CTL (left), EXP1 (middle), and EXP1 minus CTL (right), respectively. The spatial distribution is averaged for the entire period of simulation. The thin black contour in CTL, EXP1, and EXP1 minus CTL means over 30% of urban fraction using EGIS data. The thick contour in CTL, and EXP1 means the administrative boundary of Seoul.
Fig. 8. Mean diurnal variation of simulated 1.5-m temperature (℃) over observation site of (a) Category A (fu(EGIS) − fu(IGBP) < 0), (b) Category B (0 ≤ fu(EGIS) − fu(IGBP) < 0.3), and (c) Category C (0.3 ≤ fu(EGIS) − fu(IGBP) < 1) with observation for the entire period of simulation. ‘fu’ describes the fraction of urban land-use of IGBP and EGIS cover within the model grid box for each station.
Fig. 9. Diurnal variation of (a) sensible heat flux, (b) latent heat flux, and (c) storage heat flux for CTL (solid line) and EXP1 (dashed line) for the entire period on the observation site of Category C (0.3 ≤ fu(EGIS) − fu(IGBP) < 1).
Fig. 10. Mean diurnal variation of simulated 1.5-m temperature (℃) over observation site of (a) Category 1 (fu(IGBP) < 0.3 and (b) Category 2 (fu(IGBP) ≥ 0.3) with observation for the entire period of simulation. ‘fu’ describes the fraction of urban land-use of IGBP cover within the model grid box for each station.
Fig. 11. Diurnal variation of (a) sensible heat flux, (b) latent heat flux, and (c) storage heat flux for CTL (solid line) and EXP2 (dashed line) for the entire period on the observation site of Category 2 (fu(IGBP) ≥ 0.3).
Fig. 5. Diurnal variation of (a) mean and (b) RMSE of the 1.5-m temperature for CTL, EXP1, EXP2, and EXP3 simulation for the entire period.
Table 1. Summary of numerical experiments.
Table 2. Area average fraction of surface types over Seoul metropolitan for IGBP and EGIS data and differences between IGBP and EGIS (i.e., EGIS minus IGBP).
Table 3. Model evaluation statistics for 1.5 m temperature (℃) during 2-9 August 2016.
Table 4. RMSE of 1.5 m temperature (℃) for CTL and EXP1 with different urban fraction change category between IGBP and EGIS.
Table 5. RMSE of 1.5 m temperature (℃) for CTL and EXP2 with different urban fraction category of IGBP.
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