Wang Guiling

Study on MODIS Data and Characteristic of Urban Boundary LayerWang GuilingDepartment of Atmospheric Science, Nanjing UniversityJune 12,2004: 

Study on MODIS Data and Characteristic of Urban Boundary Layer Wang Guiling Department of Atmospheric Science, Nanjing University June 12,2004

Slide2: 

Introduction of multiscale meteorology and dispersion of pollutant model system developed by our lab Estimate the urban effect to the model system with the aid of remote sensing data Further work in future

Problems in the Research: 

Problems in the Research Urban heterogeneous surface Complex interaction via the surface and /or atmosphere Sparse meteorological stations in urban area

Slide5: 

To provide the structure of ABL(atmospheric boundary layer) in the urban region with the remote sensing measurements To quantitatively gauge urban surface to the overall urban effect in the mesoscale processes for momentum and heat transports To derive a better scientific understanding of how landcover changes associated with urbanization in the area. Purpose of the Research

Multi-scale meteorology and pollutant dispersion model system: 

Multi-scale meteorology and pollutant dispersion model system Urban scale Urban subdomain scale Regional scale Urban canyon scale

Slide7: 

Height of terrain

Slide8: 

3D wind fields in winter

Slide9: 

3D wind fields in summer

Slide10: 

Surface temperature in winter

Slide11: 

Surface temperature in summer

Slide12: 

Pollutant concentration in summer

Slide13: 

Pollutant concentration in winter

Surface Variable Data from MODIS: 

Surface Variable Data from MODIS The distribution characteristic of surface heat fluxes in urban heterogeneous landscape can be simulated.The results will be validated through remote sensing observation data. Five surface variables are needed include surface albedo ,surface temperature, NDVI , LAI ,landcover in the research.

Slide15: 

Surface Reflectance in Yangtse Delta

Slide16: 

Surface Temperature in Yangtse Delta

Slide17: 

NDVI in Nanjing Area

Slide18: 

Landcover in Yangtse Delta

Slide19: 

The values are also in grid form. There are 17 landcover classifications. The details are water 0 ， evergreen needle leaf forest 1 ,evergreen broadleaf forest 2 ， deciduous needle leaf forest 3 ,deciduous broadleaf forest 4 ， mixed forests 5 ， closed shrub land 6 ， open shrub lands 7 ,woody savannas 8 ， savannas 9 ， grasslands 10 ， permanent wetlands 11,croplands 12， urban and built-up 13 ， cropland/natural vegetation mosaic 14,snow and ice 15 ， barren or sparsely vegetated 16.

Validation of Surface Temperature: 

Validation of Surface Temperature Difference between surface temperatures from MODIS and AWS

Further Work: 

Further Work To validate more remote sensing data with field observation To quantitatively gauge urban surface to the overall urban effect in the mesoscale processes for momentum and heat transports through time at nested spatial scales from local to regional To model the relationship between urban growth, land cover change, the development of the urban heat island phenomenon,and urban polluting property