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Chinese Cryosphere Information System

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Title: Chinese Cryosphere Information System


1
Chinese Cryosphere Information System
Li Xin
Cold and Arid Regions Environment and Engineering
Research Institute, CAS
2
1. Introduction Cryosphere and Climate Change
3
2. Structure of CCIS
4
Hardware and Software Environment in CCIS
ARC/INFO
PC
ArcView
UNIX Workstation
NT Workstation
Applications in different environment
5
3. Main Case Study Areas of CCIS
Qinghai-Tibet Highway
Qinghai-Tibet Plateau
Urumqi River Basin, Tienshan Mountains
6
3.1 CCIS Qinghai-Tibet Plateau
7
DEM
8
Map of Frozen Ground
9
Vegetation Map of the QTP
10
3.2 CCIS Regions along the Qinghai-Tibet highway
11
Database of frozen Soil Engineering Properties
along the Qinghai-Tibet Highway
12
3.3 CCIS Urumqi River Basin in the Tienshan
Mountains
13
DEMs of Glacier
14
4. Spatial Interpolation of Climatic Variables
  • Missing data estimation
  • Data gridding

15
Classification and Procedure of Spatial
Interpolation
  • Geometric method
  • Statistical method
  • Geostatistical method
  • Functional method
  • Stochastic simulation
  • Physical model simulation
  • Combined method

16
Meteorological Stations in the Qinghai-Tibet
Plateau
17
Inverse Distance Weighting
18
Interpolation results of inverse distance square
19
Trend Surface
20
Interpolation results of trend surface
21
Kriging method
22
Exploratory Spatial Data Analysis
  • The mathematical expectation of the difference
    between two points separated by distance h is
    zero
  • The variance of the difference between two points
    separated by distance h is minimized as
  • Hence, the semi-variance can be calculated from
    data samples by the following equation

23
Basic variogram models
24
Cokriging method
  • cokriging introduces a new hypothesis, the
    variance of the difference between two variables
    is minimized
  • The equation of cross-variogram is as follows

25
Fit of simple and cross-variogram
26
Interpolation results of cokriging
27
Combined method
  • 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
Lapse rates of different latitudinal and
altitudinal zones in the Qinghai-Tibet Plateau
(?C/100m)
29
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30
a sum of nugget, linear and Gaussian variogram
models
31
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32
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33
Conclusion
  • 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.
  • 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
5. Response of Permafrost to Global Change on the
Qinghai-Tibet Plateau - A GIS Aided Model
35
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36
Altitude Model
37
Data Flow in the Altitude Model
Geo thermal Regime
GCM Scenarios
38
DEM of Qinghai-Tibet Plateau
39
Diagram of HADCM2
40
The Air Temperature Rise on the Qinghai-Tibet
Plateau in 2049
41
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42
Nelson Frost Number Model
43
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44
Assumptions
  • The Gaussian function that describes high
    altitude permafrost distribution will not change
    according to the climate warming.
  • 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 (?T) and the
    increased height of permafrost lower limit (?H).
    The relation is
  • Lakes, glaciers, deserts will not change

45
Permafrost Change when Air Temperature Rise 0.51C
Permafrost Change when Air Temperature Rise 1.10C
Permafrost Change when Air Temperature Rise 2.91C
46
Permafrost Change on the Qinghai-Tibet Plateau
8.03
18.45
58.18
47
6. Other Models
48
6.1 Solar Radiation Model over Rugged Terrain
  • Duration of possible sunshine Odefined as the
    set of duration when the sloping grid can receive
    direct solar radiation during the entire day.
  • Isotropic view factor Visodefined 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.
  • Circum-solar view factor V1defined 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.
  • Shape factor Fijdefined as the ratio of the
    energy reached another sloping grid to the energy
    emitted from the source sloping grid.

49
Duration of Possible Sunshine
50
Obstruction of solar radiation by the surrounding
terrain
z
y
x
51
Ray trace algorithm
52
Isotropic View Factor
z
y
x
53
Shape Factor
54
????????
55
Spectral reflectance Inverse
--with a Windows 95 Style User Interface
56
Obstruct in winter
Obstruct in summer
57
Result - Net Solar Radiation
58
6.2 Relationship between mass balance, solar
radiation and air temperature
59
Relationship between mass balance, solar
radiation and air temperature of Glacier No. 1
  • Bj84471.3T 37.3Ip
  • correlation coefficient (R)0.9121 R20.8320

60
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61
lt-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 gt0.5?C Extreme unstable type
Present
2009
2049
2099
6.3 Change of Permafrost-Engineering Properties
along the Qinghai-Tibet Highway (Tutuhe )
62
The change of permafrost stability alongthe
Qinghai-Tibet Highway
63
6.4 A Distributed Calculation Method for Glacier
Volume Change
1964
64
Calculation of glacier mass balance using GIS
65
Thanks
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