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2000-02-14 1 Chinese Cryosphere Information System Li Xin Cold and Arid Regions Environment and Engineering Research Institute, CAS.

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Presentation on theme: "2000-02-14 1 Chinese Cryosphere Information System Li Xin Cold and Arid Regions Environment and Engineering Research Institute, CAS."— Presentation transcript:

1 2000-02-14 1 Chinese Cryosphere Information System Li Xin Cold and Arid Regions Environment and Engineering Research Institute, CAS

2 2000-02-14 2 1. Introduction: Cryosphere and Climate Change

3 2000-02-14 3 2. Structure of CCIS

4 2000-02-14 4 Hardware and Software Environment in CCIS ARC/INFO UNIX WorkstationNT Workstation ArcView Applications in different environment PC

5 2000-02-14 5 3. Main Case Study Areas of CCIS Qinghai-Tibet Plateau Qinghai-Tibet Highway Urumqi River Basin, Tienshan Mountains

6 2000-02-14 6 3.1 CCIS: Qinghai-Tibet Plateau

7 2000-02-14 7 DEM

8 8 Map of Frozen Ground

9 2000-02-14 9 Vegetation Map of the QTP

10 2000-02-14 10 3.2 CCIS: Regions along the Qinghai-Tibet highway

11 2000-02-14 11 Database of frozen Soil Engineering Properties along the Qinghai-Tibet Highway

12 2000-02-14 12 3.3 CCIS: Urumqi River Basin in the Tienshan Mountains

13 2000-02-14 13 DEMs of Glacier

14 2000-02-14 14 4. Spatial Interpolation of Climatic Variables l Missing data estimation l Data gridding

15 2000-02-14 15 Classification and Procedure of Spatial Interpolation Geometric method Statistical method Geostatistical method Functional method Stochastic simulation Physical model simulation l Combined method Data Model Specification Estimation of surface mean Estimation of second order (covariance, variogram) properties of surface Model evaluation Interpolation

16 2000-02-14 16 Meteorological Stations in the Qinghai-Tibet Plateau

17 2000-02-14 17 Inverse Distance Weighting

18 2000-02-14 18 Interpolation results of inverse distance square

19 2000-02-14 19 Trend Surface

20 2000-02-14 20 Interpolation results of trend surface

21 2000-02-14 21 Kriging method

22 2000-02-14 22 Exploratory Spatial Data Analysis l The mathematical expectation of the difference between two points separated by distance h is zero: l The variance of the difference between two points separated by distance h is minimized as: l Hence, the semi-variance can be calculated from data samples by the following equation:

23 2000-02-14 23 Basic variogram models

24 2000-02-14 24 Cokriging method l cokriging introduces a new hypothesis, the variance of the difference between two variables is minimized l The equation of cross-variogram is as follows:

25 2000-02-14 25 Fit of simple and cross-variogram

26 2000-02-14 26 Interpolation results of cokriging

27 2000-02-14 27 Combined method l Assuming that spatial variable consists of three components: one structural component, one stochastic and spatial correlated component, and one stochastic noise or residual. Let x denotes a two-dimensional or three-dimensional vector, spatial variable Z(x) can be expressed as:

28 2000-02-14 28 Lapse rates of different latitudinal and altitudinal zones in the Qinghai-Tibet Plateau (  C/100m)

29 2000-02-14 29

30 2000-02-14 30 a sum of nugget, linear and Gaussian variogram models

31 2000-02-14 31

32 2000-02-14 32

33 2000-02-14 33 Conclusion l Spatial interpolation is a very important spatial analysis tool in GIS. As for the cryospheric regions with sparsely and irrationally distributed meteorological stations, spatial interpolation is a basic method for the study of spatial distribution of climatic variables and also a prerequisite for the establishment of cryospheric models based on GIS. l There is no absolutely optimal spatial interpolation method; there is only relatively optimal interpolation method in special situation. Hence, the best spatial interpolation method should be selected in accordance with the qualitative analysis of the data, exploratory spatial data analysis and repeated experiments.

34 2000-02-14 34 5. Response of Permafrost to Global Change on the Qinghai-Tibet Plateau - A GIS Aided Model

35 2000-02-14 Permafrost Response to Climate Change Permafrost Forecast Physical Model Frost Number Model Altitude Model Permafrost Map GCM Model Climate Change Scenarios GIS

36 2000-02-14 Altitude Model

37 2000-02-14 Geo thermal Regime GCM Scenarios Data Flow in the Altitude Model

38 2000-02-14 DEM of Qinghai-Tibet Plateau

39 2000-02-14 39 Diagram of HADCM2

40 2000-02-14 40 The Air Temperature Rise on the Qinghai-Tibet Plateau in 2049

41 2000-02-14 41

42 2000-02-14 Nelson Frost Number Model

43 2000-02-14 43

44 2000-02-14 44 Assumptions: l The Gaussian function that describes high altitude permafrost distribution will not change according to the climate warming. l If air temperature increases 1  C, the vertical zonation will rise a certain height agreeing on the lapse rate, the lower limit of the high-altitude permafrost will rise the same height. Therefore, a relation can be established between the air temperature rise (ΔT) and the increased height of permafrost lower limit (ΔH). The relation is: l Lakes, glaciers, deserts will not change

45 2000-02-14 45 Permafrost Change when Air Temperature Rise 0.51°C Permafrost Change when Air Temperature Rise 1.10°C Permafrost Change when Air Temperature Rise 2.91°C

46 2000-02-14 46 Permafrost Change on the Qinghai-Tibet Plateau 8.03 18.45 58.18

47 99-11-20 47 6. Other Models

48 2000-02-14 48 6.1 Solar Radiation Model over Rugged Terrain l Duration of possible sunshine Ω : defined as the set of duration when the sloping grid can receive direct solar radiation during the entire day. l Isotropic view factor V iso : defined as the ratio of the area of the visible part to the area of semi-sphere on a sloping grid. It stands for the influence of the surrounding terrain to the isotopic diffuse radiation. l Circum-solar view factor V 1 : defined as the ratio of the exoatmospheric radiance obstructed by surrounding and self- shadowing to the exoatmospheric radiance obstructed only by self- shadowing. It stands for the influence of the surrounding terrain to the circum-solar diffuse radiation. l Shape factor F ij : defined as the ratio of the energy reached another sloping grid to the energy emitted from the source sloping grid.

49 2000-02-14 49 Duration of Possible Sunshine

50 2000-02-14 50 Obstruction of solar radiation by the surrounding terrain x y z 被地形遮蔽的光线 未被地形遮蔽的光线 1 2 3 4

51 2000-02-14 51 开始 设置追踪深度 追踪数 =0 ;遮蔽 = 假 是否与多边形相交 求交点 追踪单元 小于追踪深度 交点是否在多边形内 结束 否 是 是 遮蔽 = 真 是 否 否 Ray trace algorithm

52 2000-02-14 52 x y z h Isotropic View Factor

53 2000-02-14 53 Shape Factor r ii jj A i dA i A j dA j

54 2000-02-14 54 太阳辐射分量计算

55 2000-02-14 55 --with a Windows 95 Style User Interface Spectral reflectance Inverse

56 2000-02-14 56 Obstruct in winter Obstruct in summer

57 2000-02-14 57 Result - Net Solar Radiation

58 2000-02-14 58 6.2 Relationship between mass balance, solar radiation and air temperature

59 2000-02-14 59 Relationship between mass balance, solar radiation and air temperature of Glacier No. 1 B j =844—71.3T —37.3Ip correlation coefficient (R)=0.9121; R 2 =0.8320

60 2000-02-14 60

61 2000-02-14 61 Present 2009 2049 2099 6.3 Change of Permafrost-Engineering Properties along the Qinghai-Tibet Highway (Tutuhe ) <-5  C: Extreme Stable type -5  C to -3  C: Stable type -3  C to -1.5  C: Sub-stable type -1.5  C to -0.5  C: Transit type -0.5  C to 0.5  C: Unstable type >0.5  C: Extreme unstable type

62 2000-02-14 62 The change of permafrost stability along the Qinghai-Tibet Highway

63 2000-02-14 63 6.4 A Distributed Calculation Method for Glacier Volume Change 1964

64 2000-02-14 64 Calculation of glacier mass balance using GIS

65 2000-02-14 65 Thanks


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