Vulnerability assessment and analysis of cryosphere changes in the Western Sichuan Plateau

Figures & data

Figure 1. (a) Geographic location and (b) basin distribution in the study area: (I) Jialing River Basin, (II) Yellow River Basin, (III) Minjiang River Basin, (IV) Yalong River Basin, and (V) Jinsha River Basin). (c) Administrative divisions and topography.

Table 1. Vulnerability assessment index system of cryosphere changes in the Western Sichuan Plateau.

Target layer	Guideline layer	Weights	Indicator layer	Combined weights
Vulnerability to cryosphere changes	Exposure	0.25	Glacier area change rate	0.015
			Accumulative snow depth change rate	0.061
			Annual average ground temperature change rate	0.029
			Slope	0.029
			Altitude	0.116
	Sensitivity	0.25	Temperature change rate	0.137
			Precipitation change rate	0.086
			NPP change rate	0.027
	Adaptability	0.50	Urbanization rate	0.026
			Total agricultural output value	0.099
			Per capita GDP	0.147
			Per capita grassland area	0.039
			Year-end livestock inventory	0.038
			Local fiscal revenue	0.040
			Transportation capacity	0.112

Table 2. Type of interaction detection.

Judgment	Interactions
$\mathit{q}\left(\mathit{X}1\cap \mathit{X}2\right)<\mathit{Min}\left(\mathit{q}\left(\mathit{X}1\right),\mathit{q}\left(\mathit{X}2\right)\right)$	Nonlinear attenuation
$\mathit{Min}(\mathit{q}\left(\mathit{X}1\right),\mathit{q}\left(\mathit{X}2\right)<\mathit{q}\left(\mathit{X}1\cap \mathit{X}2\right)<\mathit{Max}\left(\mathit{q}\left(\mathit{X}1\right),\mathit{q}\left(\mathit{X}2\right)\right)$	Single-factor nonlinear attenuation
$\mathit{Min}(\mathit{q}\left(\mathit{X}1\right),\mathit{q}\left(\mathit{X}2\right)<\mathit{q}\left(\mathit{X}1\cap \mathit{X}2\right)<\mathit{Max}\left(\mathit{q}\left(\mathit{X}1\right),\mathit{q}\left(\mathit{X}2\right)\right)$	Two-factor enhancement
$\mathit{q}\left(\mathit{X}1\cap \mathit{X}2\right)>\mathit{Max}\left(\mathit{q}\left(\mathit{X}1\right),\mathit{q}\left(\mathit{X}2\right)\right)$	Independent
$\mathit{q}\left(\mathit{X}1\cap \mathit{X}2\right)\mathit{q}\left(\mathit{X}1\right)+\mathit{q}\left(\mathit{X}2\right)$	Nonlinear enhancement

Figure 2. Spatially distributed vulnerability levels of cryosphere changes in the Western Sichuan Plateau. (a) Spatial distribution of Vulnerability levels. (b) Spatial distribution of Exposure levels. (c) Spatial distribution of Sensitivity levels. (d) Spatial distribution of Adaptability levels.

Figure 3. Spatial relationship and LISA cluster map of vulnerability to cryosphere changes in the Western Sichuan Plateau. (a) Moran Scatter Chart of Vulnerability. (b) LISA Cluster Chart of Vulnerability.

Figure 4. Spatial relationship between dimensions of vulnerability to cryosphere changes in the Western Sichuan Plateau. (a) Moran Scatter Chart of Exposure and Sensitivity. (b) Moran Scatter Chart of Exposure and Adaptability. (c) Moran Scatter Chart of Sensitivity and Adaptability.

Table 3. Detection results of influencing factors on the vulnerability to cryosphere changes in the Western Sichuan Plateau.

Influence factors	q-Value	Order	Influence factors	q-Value	Order
Per capita GDP	0.494	3	Precipitation change rate	0.424	5
Temperature change rate	0.673	1	Accumulative snow depth change rate	0.454	4
Altitude	0.550	2	Local fiscal revenue	0.175	9
Transportation capacity	0.236	8	Per capita grassland area	0.354	6
Total agricultural output value	0.303	7	Year-end livestock inventory	0.123	10

Figure 5. Interaction detection results of influencing factors on the vulnerability to cryosphere changes in the Western Sichuan Plateau.

Table 4. Changes in the number and area of glaciers in the Western Sichuan Plateau from 2007 to 2017.

Basin name	In 2007		In 2017
	Number of glaciers (pieces)	Glacier area (km^2)	Number of glaciers (pieces)	Glacier area (km^2)
The Yellow River Basin	0	0	0	0
Jialing River Basin	5	0.850	5	0.526
Minjiang River Basin	294	308.582	312	300.207
Yalong River Basin	207	143.942	224	124.232
Jinsha River Basin	190	184.077	360	159.914
Total	696	637.451	817	584.879

Figure 6. Distribution and changes of various types of permafrost in the Western Sichuan Plateau: (a) maximum freezing depth of seasonal permafrost in the 1960s, (b) maximum freezing depth of seasonal permafrost in the 2010s, (c) active layer thickness of perennial permafrost in the 1960s, and (d) active layer thickness of perennial permafrost in the 2010s.