**3.2 Assessment of GLOF using remote sensing data and GIS**

Rugged mountain conditions make it difficult to investigate the glacial lakes for the whole region. However, the end moraine and the lakes in the blocked river valleys (e.g., Khurdopin glacial lake) were investigated with physical visits. However, the area's calculations and the causes of surging were made through remote sensing data and GIS

**109**

*Risks of Glaciers Lakes Outburst Flood along China Pakistan Economic Corridor*

**) Ice reserve (km3**

Swat 233 223.55 12.221 255 15.86 2 Chitral 542 1903.67 258.817 187 9.36 1 Gilgit 585 968.1 83.345 614 39.17 8 Hunza 1050 4677.34 808.794 110 3.21 1 Shigar 194 2240.08 581.27 54 1.09 0 Shyok 372 3547.84 891.8 66 2.68 6 Indus 1098 688 46.38 574 26.06 15 Shingo 172 36.91 1.009 238 11.59 5 Astore 588 607.03 47.931 126 5.52 9 Jhelum 384 148.18 6.943 196 11.78 5

**Glaciers Glacial lakes**

**) No. Area (km2**

**) Potential danger**

techniques. The Landsat satellite images for May and June 2017 were downloaded from the website; http://earthexplorer.usgs.gov/ to explore the formation of newly developed lakes due to river blockage caused by the surging of Khurdopin glacier. The formation of the newly developed lakes was identified from the visual interpretation of the images in the ArcGIS tool, whereas Temporal Geodetic mass balance is employed to compute the vertical changes in glaciers by using remote sensing data of that region. The potential GLOF lakes were identified base on the following criteria

*Summary of glaciers, glaciers lakes, and potentially dangerous lakes in CPEC region [31].*

The rise in water level in glacial lakes, which creates the condition to breach the lake. The lakes form on the glacial surface, which produces the combined effect with a

The valley lake also becomes the potential GLOF lake due to short distance from

A lake several times breaches and damages the downstream. These types of lakes

The physical conditions of the surrounding of the lake also play a vital role to

There is still no standard to identify the potential glacial lakes. The above men-

Remote sensing and field investigations are two basic methodologies used to assess the GLOF events (**Table 2**) and their credible effects. The number of glacial lakes, their areas, and geodetic mass balance for surging glaciers have been estimated through remote sensing techniques; whereas, field investigations help to assess the severity of the GLOF event. Moreover, the possible disaster from the potential hazard lake can be investigated through field investigations in terms of

Pakistan Snow and Ice Hydrology Project (PSIHP) of WAPDA in collaboration with a Canadian University studied the Khurdopin glacier for precipitation input. They also did field visit of Batura glacier and Passu lake through the collaboration of Joint Venture of National Science Foundation of China, under the umbrella of the institute of international Rivers and Eco-security, Yunnan University,

mother glaciers tongue and the size of lake also plays an important role.

tion criteria and condition decide the potential dangerous glacial lakes.

barrier strength, discharge conditions, and depth of the lake.

*DOI: http://dx.doi.org/10.5772/intechopen.93459*

**no. Area (km2**

**River basins**

**Table 1.**

and physical conditions [24]:

filled again and breach again.

group of lakes. It became potentially dangerous lakes.

identify the potential dangerous glacial lake.

**3.3 Field investigations for GLOF events**


*Risks of Glaciers Lakes Outburst Flood along China Pakistan Economic Corridor DOI: http://dx.doi.org/10.5772/intechopen.93459*

#### **Table 1.**

*Glaciers and the Polar Environment*

April, respectively [30].

**Figure 1.**

**3. Materials and methods**

*Study area of China Pakistan economic corridor.*

**3.1 Glaciers along CPEC route**

as major lakes, which contribute 62% of the total lakes. These major lakes form 93% of the lake area of the basin. New glacial lakes also formed due to glaciers thinning and retreating of this region. These lakes are categorized according to risk, 52 glacial lakes identified in this region. Passu lake has experienced historical GLOF events, which lie in the Hunza River basin [6]. The location of Passu lake is 38 km away and directed to the East-West of Passu glacier in the HKH region (**Figure 1**). The climate of Hunza is moderate, which have minimum and maximum temperature of 16 and 35.9°C, respectively. The annual average rainfall in this region is 136.2 mm with a minimum (2.1 mm) and maximum (283.2 mm) in November and

The CPEC route passes through the Hunza River basin which is a glaciated region of Gilgit Baltistan. The route starts from China to Pakistan through the Sost border which lies in the Hunza River basin. Approximately, 28% of the Hunza basin area is covered by glaciers, and Passu, Batura, and Ghulkin are some known glaciers that exist along the CPEC route (**Table 1**), which have an established history of GLOF events. The Karakoram Highway and other roads in Shimshal and the Nagar River basins have been damaged many times because of GLOF events from the glaciers.

Rugged mountain conditions make it difficult to investigate the glacial lakes for the whole region. However, the end moraine and the lakes in the blocked river valleys (e.g., Khurdopin glacial lake) were investigated with physical visits. However, the area's calculations and the causes of surging were made through remote sensing data and GIS

**3.2 Assessment of GLOF using remote sensing data and GIS**

**108**

*Summary of glaciers, glaciers lakes, and potentially dangerous lakes in CPEC region [31].*

techniques. The Landsat satellite images for May and June 2017 were downloaded from the website; http://earthexplorer.usgs.gov/ to explore the formation of newly developed lakes due to river blockage caused by the surging of Khurdopin glacier. The formation of the newly developed lakes was identified from the visual interpretation of the images in the ArcGIS tool, whereas Temporal Geodetic mass balance is employed to compute the vertical changes in glaciers by using remote sensing data of that region. The potential GLOF lakes were identified base on the following criteria and physical conditions [24]:

The rise in water level in glacial lakes, which creates the condition to breach the lake. The lakes form on the glacial surface, which produces the combined effect with a group of lakes. It became potentially dangerous lakes.

The valley lake also becomes the potential GLOF lake due to short distance from mother glaciers tongue and the size of lake also plays an important role.

A lake several times breaches and damages the downstream. These types of lakes filled again and breach again.

The physical conditions of the surrounding of the lake also play a vital role to identify the potential dangerous glacial lake.

There is still no standard to identify the potential glacial lakes. The above mention criteria and condition decide the potential dangerous glacial lakes.

#### **3.3 Field investigations for GLOF events**

Remote sensing and field investigations are two basic methodologies used to assess the GLOF events (**Table 2**) and their credible effects. The number of glacial lakes, their areas, and geodetic mass balance for surging glaciers have been estimated through remote sensing techniques; whereas, field investigations help to assess the severity of the GLOF event. Moreover, the possible disaster from the potential hazard lake can be investigated through field investigations in terms of barrier strength, discharge conditions, and depth of the lake.

Pakistan Snow and Ice Hydrology Project (PSIHP) of WAPDA in collaboration with a Canadian University studied the Khurdopin glacier for precipitation input. They also did field visit of Batura glacier and Passu lake through the collaboration of Joint Venture of National Science Foundation of China, under the umbrella of the institute of international Rivers and Eco-security, Yunnan University,


#### **Table 2.**

*History of major GLOF events in CPEC region.*

Kunming, China, and ICIMOD. The remote sensing and field observations analysis of Khurdopin glacier provides up to date evidence about glacier surge and its possible impacts on the downstream populations because of the newly developed lake.
