Sikkim State Climate Change Cell (SCCC) under Sikkim State Council of Science

and Technology

Sikkim

Sikkim is one of the mountainous states of Indian union. It is located in tectonic active

area along the Himalayas, earthquake is frequent. Elevation gradient (300-8000 meters)

within 113 km North South and 64 km East West extension makes the steep gradient

topography. High gradient slope provides more power to river and stream for erosion

activities. So landslides and flash flood are common during the rainy season.Majority of

state population lives in this hill slopes in rural areas with agriculture as the primary

occupation. The accessibility within the state meet through mountain roads constructed

in varying slopes which remain cut off during rainy season. In this situation the state

population directly and indirectly depends on nature for their livelihoods. Climate change

and its impacts are likely to pose serious impact on the life of people in the state.

Sikkim State Climate Change Cell

Sikkim State Climate Change Cell was established in October 2014 under Sikkim State

Council of Science and Technology, an autonomous organisation of Department of

Science and Technology, Government of Sikkim. The Cell is established under National

Mission for Sustaining the Himalayan Eco-system (NMSHE), one of the missions under

National Action Plan on Climate Change, supported by Department of Science and

Technology, Government of India. State Climate Change Cell has the mandate to focus

and address various issues related with climate change to fulfil the objectives of

NMSHE and State Action Plan on Climate Change (SAPCC).

Initiatives

The Centre has undertaken two kinds of initiatives, one with focus on conservation of

natural ecosystem and study of impact of climate change on Himalayan ecosystem and

another with focus on human lives and livelihood that will help the people in the state

directly and indirectly to tackle the impact of climate change.

Goals and Objectives

Vulnerability and Risk Assessment at Gram Panchyat Unit (GPU) and ward

level

The state has total number of 176 GPU and 989 wards in its four district of

Sikkim. Vulnerability and risk assessment provides level of vulnerability within

GPU to prioritize the adaptation measures.

Institutional Capacity building to attain the capability to handle climate change

program and to find the solutions to address the problem of climate change in the

state. To carry out Research and Development activities for data base generation

as per the SAPCC and NMSHE requirements.

1. Training programmes for stakeholders including Government officials,

researchers, community based organizations, media etc in the state to work for

the minimizing the affect of climate change in the state and to achieve the

sustainable development.

2. Involving masses to work for minimizing the impact of climate Change through

awareness programme.

The Progress made so far:

1. Generation of database for the vulnerability and risk assessment of state in

terms of climate change:

The Centre is presently engaged in database generation for vulnerability

assessment on the impact of Climate Change in different areas including rural

and urban vulnerability, agricultural vulnerability, human health vulnerability etc.

Vulnerability assessment requires series of database including meteorological

data, Population census data, data on land use land cover, data on human health

and agriculture etc to meet the parameters on exposure, sensitivity and adaptive

capacity. Apart from these data sets, proper boundary delineation map of wards

and GPU is required to calculate the area of each ward and GPU. The complete

data set would be integrated in GIS Platform to generate the degree of exposure,

sensitivity and availability of adaptive capacity within wards and GPU. Based on

these parameters, the level of vulnerability will be calculated among the wards

and GPU. It will help in prioritizing Climate Change Adaptation programme in the

state.

Recently the number of ward and GPU of Sikkim has been increased after the

delimitation. The new ward and boundary is not been finalized so far in Sikkim.

Apart from that, there is a need of series of correction in available ward and GPU

boundaries ofSikkim. As such there is a need of much effort in correction and

finalization of these boundaries. At present work is going on to fulfill database

needs as well as to fulfill the limitation of boundaries.

2. Vulnerability assessment in terms of natural disaster:

The state being the mountainous state is vulnerable to different kinds of natural

disaster. Disaster like landslide, river and stream floods, forest fires etc are

common in the state. The impact of climate change is likely to aggravate this

disaster in the state. As such the study of these hazards is very important. The

Centre is presently engaged in following areas of studies:

a. Landslide hazard zonation: Landslide is one of the important hazard in

Sikkim. With the onset of monsoon landslide become frequent in the state.

Roads which are the only means of transport remain frequent blockages

during the rainy season. The landslide also causes huge damages of lives

and property in the state. Each year landslide brings tremendous worry in

the life of people in the state. As such study of landslides becomes one of

the important objectives of the Centre. At present the Centre is engaged in

inventory mapping of the major landslides in Sikkim using the satellite

imageries. The final outcome of the studies will provide the proper

landslide hazard zonation which will help in vulnerability assessment and

mitigation of climate change in the state.

b. Study of Glacial Lake Outburst Floods: Climate Change has direct

impact on snow and glacier of Indian Himalayas. In recent times most of

the glacier in the Himalayas are reported to be retreat very fast. The fast

melting of the glacier result in formation of glacial lakes in higher altitudes.

In Sikkim large number of glacier Lakes are in the process of formation

due to the melting of the glaciers. These glacial lakes are formed in loose

moraines which sometimes burst and caused huge damages in

downstream. As such, the Centre is also working on this areas of natural

disaster. At present the Centre is engaged in study of South Lhonak

glacial which has attained more than 126 ha in area in last few years. The

lake was around 18 ha in 1976 and small lakes in 1960s, which now

attained more than 2.3 km in length. In last field visit, the Centre has

undertaken Bathymetry survey and electrical resistivity survey of the lake

in order to know the volume of the lake and to understand the subsurface

composition of materials beneath the moraine damming the huge glacial

lake. Like South Lhonak Lake, Shako Tsho Lake in North Sikkim is also

one of the vulnerable glacial lakes in Sikkim that posed threat of GLOFs in

Sikkim.

c. Study of river flood areas in Sikkim: River flood is one of the important

hazard associated with heavy rainfall during the monsoon season. The

flood may posed huge destruction along the river at a time of floods. The

cloud burst which is often associated with climate change causes

tremendous damages in the stream and rivers along with its catchment

areas. As such at present the Centre is engaged in mapping and study of

rivers and major streams of state. The final goal of the study is to find out

the vulnerable settlement along the rivers in case of cloud burst induced

floods.

3. Institutional Capacity building and R&D for data base generation:

Prior to establishment of State Climate Change Cell, the State Council of Science

and Technology had been working on various areas of climate change related

studies in Sikkim. Among them study of glacier dynamics of East Rathong

Glacier located in West Sikkim is one of the major studies funded by DST, GOI.

Other studies are monitoring of snow cover of Sikkim Himalayas considering

Tista and Rangit basin. Apart from that, Council is working on glacial hazards in

terms of glacial lake outburst flood studies, wetland mapping, land use and land

cover mapping etc. The establishment of state climate change cell has

providedstrong support and broad perspectives for the ongoing climate change

studies.With the establishment of State Climate Change Cell, the Council has

strengthened with more number of manpower and equipment for the ongoing

researches. The Manpower of the Centre is well trained in terms of Glaciers

monitoring, climate change and vulnerability assessment in different capacity

building programmes like Indo Swiss Capacity Building programme, Field training

Programme on Glaciology of GSI, as supported by DST, GoI. The kind of training

programme has helped in institutional capacity building of the Centre.

4. Research and development for database generation:

The Centre is engaged indatabase generations of various key sectors to fulfil the

requirement of NMSHE and SAPCC. The gap database of the state is in process

of generation and collection from other organisations. So far the Centre

possessed following important maps and integrated database.

a. Landuse landcover map

b. Wetland mapping

c. Drainage mapping

d. Glacier mapping

e. Contour generation

f. Slope map generation

g. Snow cover mapping and monitoring

h. Data generation of East Rathong Glacier etc.

5. Finalization of training module for the training programme for various

entities:

The training module on Climate Change has been prepared. The module has

been prepared as according to the training module provided during the training

programme at TERI, New Delhi on Vulnerability assessment. The additional

information on the module is included from various website on Climate Change.

The module is also prepared on the basic of climate change based studies

carried out by Sikkim State Council.

6. Public awareness: The Centre is engaged in Public awareness programme on

Climate Change through Newsletters in the local newspaper and articles,

imparting lectures to teachers of various schools of East and North Sikkim with

the help of District Institute of Education and Training (DIET).The Centre has also

imparted lectures to the students of DIET on climate change. The main idea of

involving teacher is to speed up climate change awareness in state as they

impart their ideas, learned through trainings to their students. It helps in reaching

masses in limited timeframe. The Centre will increase the public awareness

programme in the whole state in upcoming days.

Figure. Newspaper clipping

Significant Outcomes:

Sikkim State Council of Science and Technology was engaged in Climate Change

research and activities from last few years. With the establishment of State Climate

Change Centre, the work on climate change has been enhanced under one platform.

The State Council is now equipped with different kinds of equipment for research and

developmental works on climate change in Sikkim through State Climate Change Cell.

The State Council is also strengthened with dedicated manpower to work on the issue

of Climate change in the state. The Centre is now engaged on different kinds of work on

climate change under the guidelines of NIMSHE and objectives to be fulfilled under

SAPCC. This is one of the important outcome of the Centre.

Apart from that, the State Council has undertaken different climate change studies in

the state which is now continued by State Climate Change Cell has so far achieved

significant outcome. The studies are important in terms of climate change studies in the

state and fulfilled the objectives of NMSHE. The important outcomes are listed below:

1. Study of Glacial Lake Outburst flood of South Lhonak Lake:

South Lhonak lake is continuously increasing in size in last few years. The lake was

around 18 ha in 1976 which increased to more than 126 ha in 2013. The lake is purely a

glacial moraine dammed lake which is vulnerable in terms of GLOFs. The lake if burst

may cause devastation in the downstream.

Figure. Team performed both bathymetry of South Lhonak Lake and Electrical resistivity

survey of moraines in 2014

The State Climate Change Cell under Sikkim State Council is actively engaged in the

study of South Lhonak lake in support of DST, GOI and including SASE Chandigarh,

GSI, CDAC Puna, Wadia Institute of Himalayan Geology etc. In last field visit, the

Centre has conducted Bathymetry survey and Electrical Resistivity survey of the lake.

I. This is the first systematic bathymetric work in Sikkim carried out at an altitude of

5200m above mean sea level, at an extreme windy and glaciated terrain. The

bathymetric analysis revealed that lake is 53.6 million cu.m corresponding to

maximum depth of 260 feet.

II. Disaster risks were analyzed by numerical simulation of South Lhonak Glacial

Lake Outburst using the ANUGA and SMS TUFLOW models (as done by

Working Group from field bathymetric data). The simulation of peak discharge

from the lake has revealed that the water flow would take 3-4 hours to reach the

first habitat in the region, in case of GLOF event.

Figure. Bathymetric map of South Lhonak Glacial Lake (A) and 3D Terrain

model generated through DEM acquired through bathymetric survey of

South Lhonak Lake (B)

Estimated volume ≈ 5.36 X 107

m3

A

B

III. The five longitudinal profiles of moraines damming the South Lhonak Lake were

studied and revealed that evidence of ice bonded permafrost and death ice

beneath the surface. The end (recessional) moraine having massive dead ice in

the core region a few meters from the surface, whereas near the water outlet

area the dead ice was inferred located at marginally deeper levels.

IV. The study of past satellite data of Lhonak glacier lake area revealed that the area

of the lake has increased from 18 ha or 180,000 m2 in 1976 to 126 ha or

1,260,000 m2 in 2013. The increase in the area has been rapid at an

approximate rate of 25,000 m2 to 35,000 m2 per year from 1976 to 2011.

Figure: Successive increase of South Lhonak Lake from 1976-2011

2. Study of Glacial Dynamics of East Rathong Glacier:

The Sikkim State Council is working in East Rathong Glacier from last few years. The

project is funded by DST, GOI. The State Climate Change Cell continued the study of

East Rathong Glacier to fulfil the objectives of NMSHE. Major outcome of the studies

included:

Present Morpho metric status of East Rathong glacier

Himalayan mountains are very sensitive to variation as they are youngest mountain in

the world, which results in change in Himalayan glacier morpho geometry. The glacier

system is influenced by many factors such as climatic, topographic, geographic and

glacier supplying conditions. Therefore, in order to quantify glacier changes, it is very

important to collect information in terms of glacier size, elevation distribution, exposition

and other morpho-metric parameters.

Sl No. Morpho metric

Parameters

Figure Source

1 Glacier area (km2) 4.808 IRS LISS III 2013, Google

Earth , Field study, DGPS

Survey

survey, DGPS survey

2 Glacier length(km) 7.0918 do

3 Average width (m) 773.011 do

4 Accumulation

area(km2)

2.479 do

5 Ablation Area (km2) 2.328 do

7 Snout (m) 4635.25 Topcon DGPS Survey

8

9

Snout width(m)

Highest Elevation(m)

176

6900

Topcon DGPS Survey

ASTER GDEM

10 Lowest Elevation (m) 4600 Topcon DGPS Survey

Figure. Present Morphometric status of East Rathong Glacier.

Figure. Glimpses of studies in East Rathong Glacier

Frontal retreat of exposed area of East Rathong Glacier:

In between the years 1976-1990, the total length of 76 meters was retreated lengthwise

in the gap of 14 years. The maximum lengthwise retreat was recorded in between the

year 1990 to 1997 where about 269 meters were retreat in the gap of 6 years with an

average of 45 meters/years. These huge retreats of the glacier were mainly occurred

due to the thin line of glacier which was in the process of retreat from last several years.

These thin lines of the glacier are seen in the above imagery of 1990 (Figure 22). The

processes of retreat were slowed in between the year 1997-2001 where 50 meters of

glacier were retreat with an average retreat of 12 meters/year. The retreat of glacier

again increased during 2001-2006 and 2006-2012 with average retreat of 23

meters/year and 20 meters/year respectively. The overall lengthwise retreat of frontal

area of clean exposed glacier is 653 meters with an average of 18 meters/years in the

last 36 years.

Year Loss (m) No of years Average loss/year

(m)

1976-1990 76 14 5.43

1990-1997 269 6 44.83

1997-2001 50 4 12.50

2001-2006 116 5 23.20

2006-2012 142 7 20.29

Total 653 36 18.14

Table. Lengthwise retreat of frontal area of exposed clean ice from 1976-2012

Discharge measurement

Float method was used for velocity measurements. The time taken by float to cross 5 m

discharge at different points of cross section was calculated by Stop watch.From the

time readings of floats, the average time was calculated.

Figure: Discharge variations from morning to Evening in East Rathong melts water stream in 2013-2014. Status of Suspended Sediment Concentration (SSC) & (Suspended Sediment Load

(SSL) in East Rathong melt water stream

Average daily sediment concentration in East Rathong glacier stream is 106.3 mg/l and

84.20 mg/l for the year 2013 and 2014 respectively.Average Sediment Load carried by

Rathong Glacier stream is 49.94 td-1 and 37.11 td-1 in ablation season of 2013 and 2014

respectively.

Figure. Suspended Sediment Concentration ((SSC) variations at East Rathong Melts water streams (2013-2014) Vertical thinning studies of East Rathong Glacier in 2013 and 2014 by stream drill

machine

In the ablation season of 2013, the ablation rate was measured with stakes fixed with

steam drilling machines. The ablation rate was studied with the stakes fixed at different

location of the East Rathong glacier. On an average 2.93 meters, thickness (vertical

thinning) of glacier was found melted in the ablation season of 2013.

Similarly in the ablation period of 2014 (June to September), an average thinning of

3.849 m was recorded along the centreline of the glacier, which is considerably higher

than the last year melt season. A comparative figure of vertical thinning of glacier in

2013 and 2014 is given in the following table.

Stakes Exposed

height (m) June

2013

Exposed height

(m) Sept 2013

Exposed height (m) June 2014

Exposed height (m) Sept 2014

Vertical thinning (m) 2013

Vertical thinning(m)

2014 Stake 1 0.37 4.20 1.05 5.33 3.83 4.28

Stake 2 0.37 3.00 0.24 5.00 2.63 4.76

Stake 3 0.37 4.23 1.20 6.00 3.86 4.80

Stake 4 0.63 3.73 0.22 3.00 3.10 2.78

Stake 5 0.595 3.00 1.00 5.00 2.405 4.00

Stake 6 2.085 5.00 6.00 8.00 2.915 2.00

Stake 7 2.14 5.25 1.00 5.70 3.11 4.70

Stake 8 2.70 5.00 0.53 4.00 2.30 3.47

Stake 9 2.70 5.00 1.06 5.20 2.30 4.14

Average Vertical thinning

2.939 3.849

Table . The comparative records on vertical retreat of 2013 and 2014 of East

Rathong Glacier

3. Glacier inventory of Sikkim

In this analysis, an inventory of status of glaciers has been mapped using satellite

imagery of LANDSAT dated 5 November 1990 in GIS domain. About 140 glaciers

were mapped in 1990 of varying sizes of glaciers. All the mapped glaciers were

given a code based on the grids of Topographic sheet of Survey of India, 1962. The

available names of the glacier were given along with the glacier IDs.In order to know

the status of the glacier in Sikkim Himalaya, the glacier layer of 1990 were

overlapped with IRS LISS III satellite image of 13th January 2013. Based on the

layer of 1990, a new glacier layer of 2013 were generated. Finally, comparative

studies of glacier for the years 1990 and 2013 were carried out in order to detect the

changes in the status of glacier in Sikkim Himalaya.

Glacier area (Km2)

1990 2013 Change in area

(Km2) No of

Glacier Area (Km2) No of

Glacier Area (Km2)

<1 56 31.56 60 32.11 +0.55 1-3 58 102.46 55 95.87 -6.59

3-6 9 38.14 10 45.42 +7.28

6-9 9 61.24 7 47.61 -13.63

9-12 5 52.17 5 50.35 -1.82

>12 3 118.73 3 118.73 0

Total 140 404.30 140 390.10 -14.2

Table. Summary of loss in area of glaciers in between 1990 to 2013

Figure. Changes in glacier area in Sikkim from 1990 and 2013

4. Snow Cover mapping and monitoring of Sikkim Himalaya: The State Council in collaboration with Space Application Centre Ahmadabad is

engaged in mapping and monitoring of Snow cover of Sikkim Himalaya from the year

2004-2005. The State Climate Change Cell continued the snow cover monitoring of

Sikkim Himalaya for the year 2013-2014. The Centre submitted the Final Report for the

year 2013-2014 to Space Application Centre.

In this atlas, state and basin-wise snow cover statistics, maps, and seasonal

depletion curves have been provided from October 2013 to June 2014. Snow ablation

pattern was estimated for Sikkim state, Tista and Rangit basins in the Sikkim Himalaya.

In Sikkim, maximum areal extent of 52% snow was observed in the month of May 2014

in cloud cover data of 29 May 2014, and 50% snow was observed in cloud free data in

the month of February 2014. The highest snow extent of 59 % observed in Tista basin

in the months of February, and March with cloud free data and in the month of June in

cloudy data. In Rangit basins, maximum areal extent of snow of 28% and 23% observed

in the month of May 2014 and October 2013 with cloudy data and 21% snow with cloud

free data in February 2014 respectively. In Sikkim, the lowest snow recorded in the

month of October with 9% snow followed by 25% snow in December in cloud free data.

Similarly, the lowest areal extent of snow of 10% in Tista basin and 3% in Rangit basin

recorded in the same month of October 2013.

Activities proposed for the future:

Stake holder Meetings and Trainings on Climate Change adaptation.

Finalization of ward and GPU maps for the vulnerability mapping.

Finalization of climate change Vulnerability mapping of entire state.

Training of manpower of State Climate Change Cell.

Training of Government Officials, Researchers, NGOs in Climate Change related

issues.

Climate Change awareness generation programme for the Panchyat, Teachers

and Students.

Awareness generation to the general public through media and communications.

Database collection on metrological parameters of the state from IMD and other

organization.

Continuation of work on Glacier dynamics of East Rathong Glacier.

Collection of information on health parameters of the state related to Climate

change.