Abstract The Chinese Cryospheric Information System (CCIS) is an integrated Geographic Information
System for storing, managing and analyzing the cryospheric data within China. Three regions are selected as the
case study areas of CCIS with different scale. They are the Qinghai-Tibet Plateau with a scale of 1:4,000,000, the
regions along the Qinghai-Tibet Highway with a scale of 1:250,000 and the Urumqi River Basin with a scale of
1:50,000.
As an information infrastructure of the cryosphere science, a draft classification and geo-coding system that
can express the logical hierarchy of cryospheric data had been established fundamentally. Based on this, CCIS had
stored a big amount of data including maps of glacier, frozen ground and other environmental elements, digital
elevation data, observation data of meteorological stations, hydrological gauges and permafrost boreholes and
remote sensing data. CCIS is managed by ARC/INFO and can export data to other GIS environment easily since
data exchange interfaces are paid particularly attentions in CCIS.
Based on CCIS, several GIS-based models about cryospheric processes and cryospheric response to global
change had been developed. We introduce three models in this paper. They are a response model of high altitude
permafrost to global change, an evaluation model of engineering properties in permafrost regions along the
Qinghai-Tibet Highway, and a model of glacier mass balance estimation.
1 Introduction
Cryosphere is defined as the freezing part of
atmosphere, hydrosphere, biosphere and lithosphere.
This includes ice sheets, ice shelves, ice caps and
glaciers, sea ice, seasonal snow cover, lake and river
ice, and seasonally frozen ground and permafrost.
The importance of the cryosphere in the global
climate system is related to the significant seasonal
change of snow and ice cover, inducing the amount
of energy absorbed at the surface dramatically. The
global change study had shown that cryosphere is
very sensitive to global change so that the change of
cryosphere is consider as a pointer of global change.
Global warming will make a significant shrinkage
in cryosphere extend and volume, therefore
impacting greatly on human living. Global warming
will also cause a positive feedback between snow
and ice albedo and air temperature, and change
permafrost area from carbon sink to carbon source.
These processes will have great feedback on climate
system (IPCC, 1990; IPCC, 1992; Fitzharris et al.,
1995; Cheng, 1996; Nelson et al., 1993).
China has vast expanse of cryosphere and
contains a large part of the world’s middle and low-latitude
mountain glaciers. China’s permafrost area
ranks third in the world, of which the middle and
high-altitude permafrost area ranks first in the world.
And particularly, the Qinghai-Tibet Plateau plays
very important role in global change. Therefore, the
Lanzhou Institute of Glaciology and Geocryology,
Chinese Academy of Sciences (LIGG) had made
efforts to set up a GIS of Chinese cryosphere (Li et
al, 1997; Li, 1998), namely the Chinese Cryosphere
Information System (CCIS). The objectives of CCIS
are as follows:
- To make a detailed design CCIS, drafting
the system standards;
- To build up a geographic information
system that integrated closely with
cryospheric models;
- To analysis the spatial and temporal
change of Chinese cryosphere using spatial
analysis;
- To develop some application models of
cryosphere response to global change (Li
and Cheng, 1999; Li et 1998; Wu et al.,
1998; He et al, 1999).
2 Establishment of Chinese Cryos-phere
Information System
2.1 General Structure and Case Study
Areas
CCIS is a comprehensive information system
used to manage and analysis the cryospheric data of
China. The establishment of the system, in one hand,
can meet the demand of the earth system science to
provide parameters and validation data for
development of GIS-based response and feedback
models of frozen soil, glacier and snow cover to
global change; on the other hand, can provide a
scientific, effective and safe management and
analytical tool used to systematically collect and
rescue valuable cryospheric data.
The general structure of CCIS is shown in
Figure 1.
- Three regions in different scale were selected
as the main case study areas of CCIS. They are:
(1) Qinghai-Tibet Plateau, 70--105°E, 25--40°N.
- Qinghai-Tibet Highway, with 20--30 km
width on both sides.
- Urumqi river basin in the Tienshan
Mountain, 86--89°E, 42--45°N, the key study area is
located in the upper reaches of Baiyanggou between
86°45'--87°30'E and 43°00'30 N.
Figure 1. General structure of the Chinese Cryospheric Information System
2.2 System Standards
2.2.1 Geo-Coding System of Cryospheric
Data
The classification of cryospheric data should
be able to reflect their characteristics, types and
interrelationship. CCIS includes three major types
of data, namely cryospheric data, natural
environmental data and socioeconomic resource
data. Based on the classification of cryospheric data,
a draft geo-coding system that can express the
logical hierarchy of cryospheric data had been
established fundamentally. The geo-coding
principles of CCIS are as follows: it must consistent
with the classification of the cryosphere science and
can clearly reflect the logical structure of GIS. In
addition, it should be compatible with existing
international and national standards. The geo-coding
schema of CCIS is in the form: Region Code +
Source Code + Level Code + Supplement Code.
There are nine codes, first is region code, indicating
the three case study areas of CCIS; second is source
code, indicating the data source; third – sixth are
level codes, referring to the high-level classification
of cryospheric data; seventh to ninth are supplement
codes, referring to the low-level classification of
cryospheric data.
2.2.2 System Composition
CCIS is composed of four sub-systems, namely
data source, data pre-processing sub-system, data
analysis sub-system, and system users.
Data source It includes many kinds of
thematic maps, topographic maps, observation data
such as climatic, borehole and hydrological data,
and section planar drawings of permafrost-engineering
within the three case study areas.
Data pre-processing sub-system CCIS
receives various sources of data, complies and
purifies them automatically or in the man-machine
interaction way. Then, the processed data are given
unique geo-codes and stored in CCIS.
Data analysis sub-system Some spatial
analysis methods have been developed in CCIS,
including grid analysis, irregular triangular network
analysis, topographic analysis, spatial interpolation,
spatial resampling and overlay etc. We pay
particularly attention on developing some spatial
interpolation methods by combining geo-statistics
and physical processes, because there are so few
meteorological stations in cryospheric regions.
System user CCIS is an important tool used
to analyze and study cryospheric phenomena by
scientists. It is also a tool used for planning the
sustainable development of the cryosphere region
by decision-makers and planners.
2.2.3 Software and Hardware Environment
CCIS is based on client/sever architecture.
Data process and global database management is
based on a SPARC workstation, the software is
ARC/INFO 7.0 for UNIX. Local GIS database is
managed by PC ARC/INFO and ArcView 3.0a. PC
ARC/INFO and IDRISI are also used to process
not-very-complex GIS analysis and to develop
application models. CCIS can export data to other
GIS environment easily since data exchange
interfaces are paid particularly attentions.
2.2.4 Map Projection and Data Scale
The equal-area conical projection is adopted in
the Qinghai-Tibet Plateau, while the transverse
Mercator projection is adopted in the Qinghai-Tibet
Highway and the Urumqi River Basin. The scale of
the Qinghai-Tibet Plateau is 1:4,000,000, grid
resolution is 5000*5000m. The scale of the
Qinghai-Tibet Highway is 1:250,000, grid
resolution is 100*100m. The scale of the upper
reaches of Urumqi River is 1:50,000, grid resolution
is 5*5m--100*100m.
