METR155: Using Satellite Remote Sensing in Climate Model – focus on Urban

1. METR155: Using Satellite Remote Sensing in Climate Model – focus on Urban Menglin Jin, Professor Department of Meteorology San Jose State University jin@met.sjsu.edu

2. The past, present and future of climate models During the last 25 years, different components are added to the climate model to better represent our climate system http://www.usgcrp.gov/usgcrp/images/ocp2003/ocpfy2003-fig3-4.htm

3. Climate Model: • Equations believed to represent the physical, chemical, and biological • processes governing the climate system for the scale of interest It can answer “What If” questions for example, what would the climate be if CO2 is doubled? what would the climate be if Greenland ice is all melt? what………………………..if Amazon forest is gone? what…………………………if SF bay area population is doubled?

4. Three Ways to Use Remote Sensing for Climate Model • Satellite observed parameters, for example, albedo, vegetation, cloud droplet size • Study climate process/feedback • Evaluate Model Outputs

5. Definition Climate Model (per NASA Earth Observatory Glossary http://earthobservatory.nasa.gov/Library/glossary.php3?mode=alpha&seg=b&segend=d ) A quantitative way of representing the interactions of the atmosphere, oceans, land surface, and ice. Models can range from relatively simple to quite comprehensive. Model components

6. An example Urban – an example

7. An application: Urbanization - the satellite view MODIS image for Chen Du, China –satellite provides high resolution information on land cover, temperature, albedo, vegetation, aerosol, etc

8. Night Light of Tokyo data from the Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS)

9. Night Light of Paris

10. pictures made by U.S. Defense Meteorological Satellites Program (DMSP)

11. Importance of land surface skin temperature (Tskin) Land Skin Temperature is a good indicator of the energy balance at the Earth’s surface and the so-called greenhouse effect because it is one of the key parameters in land-surface processes at local, regional as well as global scales [Jin and Dickinson 2002]. (1-α)Sd +LWd-εσTskin4 +SH+LE + G= 0 The skin temperature used in calculating heat fluxes and radiation: F↑ = εσTskin4 Eq. (1) SH = CDHU(Taero-Ta) Eq. (2) LE =CDEU(qTskin*-qa) Eq. (3)

12. We use NASA EOS and NCAR Climate Model to examine the urbanization effects, in particular, urban pollution urban heat island effect (UHI)

13. 50km MODIS Urban heat island effect Daytime Nighttime 50km 50km (Jin, Dickinson and Zhang. 2005, J. of Climate)

14. Table 1: MODIS land cover table

15. MODIS Observation Beijing

17. MODIS Observed Global urban heat island effect (Jin, Dickinson, et al. 2005)

18. Comparison of skin temperature for urban and nearby forests MODIS Cities have higher Tskin than forests

19. Urbanization changes surface albedo (MODIS) (Jin, Dickinson, and Zhang 2005, J. of Climate)

20. Urbanization changes surface emissivity (MODIS)

21. Use MODIS observed surface properties into model

22. MODIS11_L2 Emissivity_BAND 32 over Houston regions Note: emissivity is missing over Houston urban regions, but available from monthly regions

23. MODIS15_A2 Leaf Area Index (LAI) over Houston regions Note: on daily product, LAI over Houston regions is missing, but available from monthly data

24. Physical Processes for UHI: The Land Surface Energy Balance (1-α)Sd +LWd-εσTskin4 +SH+LE + G= 0 On Urban system: (1-α)Sd +LWd-εσTskin4 +SH+LE + G= 0 All underlined terms are changed!

25. Urban Aerosol Effects • Change atmosphere conditions to form clouds and rainfall • Change surface insolation -> reduce urban surface temperature

26. 0oC Cloud drop Rain drop Ice crystal Ice precipitation Aerosol Direct Effect: Scattering Indirect Effect: serve as CCN surface Aerosol reduce surface insolation

27. July 2005 Satellite observations Aerosol Distributions over Land and Ocean have evident differences

28. NASA Aeronet Sites http://aeronet.gsfc.nasa.gov/ Ames has on of this site!

29. Aerosol effect on UHI

30. AERONET, New York EPA Scale, Scale, Scale!! Jin, Shepherd, King 2005 JGR

31. Aerosol decreases surface insolation Total solar radiation decreased by aerosol=20Wm-2 Based on M-D. Chou’s radiative transfer model (Jin, Shepherd, and King, 2005, JGR)

32. 4.3 Jin and Shepherd, 2008, JGR

33. Urban system vs rainfall • “Cities impact rainfall and can create their own rain and storms,” Marshall Shepherd explains. • You need three basic ingredients for clouds and rainfall to develop, “ • air unstable - air lifting • CCN • moisture Does urban have these?

34. http://www.envplan.com/abstract.cgi?id=b34102t Urban vs. Rainfall • New Paper “The Impact Of Urbanization On Current And Future Coastal Precipitation: A Case Study For Houston” By Shepherd Et Al 2010

35. Video • http://www.met.sjsu.edu/metr112-videos/MET%20112%20Video%20Library-MP4/urban%20system/

36. Use satellite data to represent urban

37. Existing Coupled Land-Atmosphere Models:Coarse Resolution, Biogeophysics Focus Turbulence production Radiation attenuation Canopy heating & cooling Radiation trapping Urban thermal properties e.g., CLM: (NCAR, DAO) NOAH: (NCEP)

38. Bare soil water Conceptual UMD-NASA CLM-Urban Model Surface type structure CLM original type: Vegetation covered regions Bare soil regions CLM-urban model: Bare soil Road Building roofs Suburban Human-grass Original trees Urban-water body (Jin et al. 2006) Urban modifies: LAI, albedo, emisisivity, heat capacity, soil moisture, roughness length, etc

39. Physical Processes for UHI: The Land Surface Energy Balance (1-α)Sd +LWd-εσTskin4 +SH+LE + G= 0 On Urban system: (1-α)Sd +LWd-εσTskin4 +SH+LE + G= 0 All underlined terms are changed!

40. CAM3/CLM3-Urban Model Results

41. Model results

42. Model results Net longwave radiation

43. Model results

44. MODIS land cover WRF-urban 5/9/2011, 8 PM 3 Km

45. WRF 1km 5/5/2011 5 PM

46. 6 PM, 5/5/2011

47. 7 PM, 5/5/2011

48. 5 PM, 5/6/2011

49. 7 PM, 5/6/2011

50. 9 PM, 5/6/2011