ADVERTISEMENTS:
The below mentioned article provides a case study on the Kafni Glacier in India.
Study Area:
The Kafni glacier is located in the Pindar basin of the Kumaon Himalayas at the border of Bageshwar and Pithoragarh districts in Uttarakhand. The current snout position of the glacier lies at 30°13’12″N and 80°03’14″E. The north-south extending Kafni glacier originates from the southern slope of Nanda Kot-a major peak in the region. The glacier is the source of river Kafni, which originates from the ice cave formed at the snout.
This river is a tributary of the Pindar River, which flows into the Alaknanda river system. The Kafni glacier consists of two tributary glaciers that are no longer connected with the main trunk. They now exist in the form of hanging glaciers and contribute to the river flow through their melt-water.
Methodology:
ADVERTISEMENTS:
The objective of selecting the Kafni glacier was to understand the impacts of the changing local climate on small glaciers. The glacier is being monitored for changes in length, area and volume using satellite imageries and DGPS. The recession pattern of the glacier has been studied by comparing the past satellite data (LANDSAT series of satellite imageries, 1976-1999) with the present data collected through DGPS during field visits in 2007 and 2008. The analysis has proved helpful in giving an overview of the changes in the snout position and glacierised area of the Kafni glacier in the last 30 years.
An automatic weather station has also been installed near the snout to understand the hydro-meteorological characteristics in the region and their linkages with the glacial melt. Along with weather monitoring, discharge patterns of the Kafni glacier have also been monitored to find the linkages between meteorological parameters and the glacial melt. Hydrological discharge data has been collected using float techniques.
Results and Analysis:
A combination of data from primary and secondary sources indicates that the average retreat rate of the Kafni glacier has been 15.7m/year between 1976 and 2009. However, the snout position of the glacier in different years shows a variation in the retreat rate during different time periods, i.e. between 1976 and 2009. It is apparent from the analysis that the average retreat rate was higher at 21.36 m/yr from 1976 – 1990 but reduced to 10.61 m/yr during 1990-99.
The average retreat increased to 12.99 m/yr between 1999 and 2006. Annual observations since 2006 shows that the Kafni snout retreated by 12.27 m/yr between 2006-07 and it continues to show a reducing trend -10.6 m/yr in 2007-08 and 10.05 m/yr in 2008-09. While the retreat rate of the glacier shows a reducing trend, however, it is important to note that given that Kafni is a smaller glacier, even a small retreat has a significant impact on the mass balance of the glacier (Figure 5.9).
The characteristics and condition of the upper ablation area – rock exposed at several places and reduction in ice thickness – will show its impact in a few years on the snout and the total length of the glacier. The equilibrium in the retreat rate may be due to the thick debris on the lower to middle portion of the glacier, which reduces the solar energy transfer to the ice surface and hence a reduction in the melting.
ADVERTISEMENTS:
Kafni, being a smaller glacier has a lower accumulation zone and therefore is more sensitive to the variations in snowfall and any change in the equilibrium line. The tributary glacier of the Kafni (being quite small in size) is now hanging, meaning that it is not directly connected any more through ice mass to the main trunk of the Kafni. This indicates the loss of a huge ice volume in the glaciated catchment of Kafni.
The glacier has vacated 14.76 per cent of its area dining 1976-1990 and another 4.06 percent during 1990 – 1999 as per analysis of this study taking the base area and year as 1976. The overall loss in the glaciated area of Kafni and its tributaries during 1976 to 1999 is 17.5 per cent (main trunk), 29 per cent (TG1) and 23 per cent (TG2) respectively. For quick referencing, the results of the Kafni glacier’s snout retreat have been shown in Figure 5.10.
Hydro-Meteorological Study:
Initial trends about correlating meltwater discharge at Kafni with rainfall and temperature were established in 2008. Discharge data collected at the glacial snout in 2008 indicates a correlation of 0.51 between discharge and rainfall (Figure 5.10), which followed a uniform pattern throughout the entire summer season except for one extreme weather event during late September when high rainfall (about 165 mm) caused increase in discharge rate to ~30 m3/s. Towards October, trends indicated that the discharge rates dropped to 15 m3/s.
Similarly, a dear correlation was observed between increase in temperature and discharge rates although the relation does not appear to be as strong as in the case of rainfall and discharge. This shows the importance of rainfall in this valley. Usually the valleys in the Kumaon Himalayas get more rain during the monsoon season as compared to the Garhwal Himalayas. With higher average temperature in August during peak discharge season, actual discharge rates vary between 18-25 m3/s, corresponding with the temperature range of 25-30°C for the same month.
In October, with the onset of the winter, discharge rates tapered off to around 10 m3/s in relation to average temperatures of about 4-8°C. Since this region was never equipped with a meteorological observatory, no analysis could be done from a hydro-meteorological point of view. This is for the first time that an attempt has been made in this part of the Himalayas to understand the hydro-meteorological characteristics of the Kafni glacier.
Remarks:
The science of climate change is complex as it is not only about temperature variations but also the impact of local environmental factors; non- climate stressors play an equally critical role. The ecologically fragile Himalayan ecosystems harbour a diverse range of flora and fauna. Moreover, ecological services generated by these ecosystems support the wellbeing of communities in the mountains and lower plains.
Smaller Glaciers – More Vulnerable:
The initial results from our field study indicate that the Himalayan glaciers are retreating, but at a reduced rate, and the larger glaciers like Gangotri are unlikely to disappear in near future, due to its large mass balance. The smaller glaciers like Kafni are retreating at a faster rate, and are not only losing more glaciated portion but also their tributary glaciers – a trend which has been observed across the Himalayas for many other smaller glaciers.
Regional climate variations could threaten the fragile nature of these glaciers, which are likely to disappear at a much faster rate or be considerably reduced in length as compared to the larger ice bodies. These glaciers are perhaps more vulnerable to local climate variations and hence long-term and continuous assessment is required to monitor the hydro-meteorological parameters existing in their vicinity to develop predictive models for future water resource scenarios.
Larger glaciers like Gangotri show a continuous recessionary trend in recent years as evidenced from the present and other studies. However, at present this trend may have a limited influence on the water flows downstream primarily due to the large extent of the glacierised area. The movements of larger glaciers are dynamic and snout retreat is a delayed response, but the fragmentation of the larger glaciers needs to be continuously monitored.
Not only climatic variations, but there also are visible changes in the social and economic dimensions of the Himalayan region. Communities living closer to Gangotri have indicated changes in snowfall levels in the winter months resulting in less soil moisture, which in turn is changing cropping patterns and availability of water. Different glaciers in the same climatological set up respond differently to the changes in climate. Hence, it becomes difficult to predict the glacier retreat or advance scenarios with confidence.
ADVERTISEMENTS:
Addressing the Data Challenge:
The current observations at the Gangotri and Kafni glaciers strengthen the existing observations especially by providing the hydro-meteorological data. This database will encourage researchers in future to conduct studies in the region of Gangotri and Kafni, as well as other glaciers.
This will further help in accurate assessments of the glacial melt and water flows based on long-term data. Better use of these technologies could provide an efficient and scientifically sound method to study different patterns and changes in the glacier systems on various spatial and temporal scales.
Since region specific climate models are limited, a long-term monitoring of meteorological parameters is crucial before arriving at definitive conclusion regarding the impact of global warming and climate change. It is also important to study the impact of local pollutants and climate variables together with non-climatic stressors.
As a way forward it is essential that more data is generated over a longer time period and that new mechanisms need to be created to ensure sharing of data to enable more in-depth research and analysis.
This will enable development of more region-specific climate models to make projections for potential future impacts and preparation of appropriate response measures and mechanisms. It is also essential to carry out a long-term study on glacier mass balance and glacier dynamics to understand the impact of climate change in the Himalayas.
Non-Climatic Stressors:
Non-climatic stressors, such as rapid economic growth, including tourism and infrastructure development are equally increasing pressure on the Himalayan belt. Unplanned development has already resulted in severe pressures on both local ecology and communities.
The impacts of climate change and changes in climate variability would further create additional stresses. The decline in glacial area and variations in annual runoff patterns in the future gains importance in the context of hydropower planning and development of the Himalayan states.
Adapting to the Change:
Glacial retreat could pose the most far-reaching challenge in the Himalayan region. The dynamics of the monsoon are influenced by Himalayan systems which act as a reservoir to sustaining agriculture, providing freshwater and groundwater recharge and are home to a unique ecosystem with many endemic species. Adaptation to climate change, therefore, requires not just local action but also trans-boundary cooperative arrangements.
Future efforts in building the resilience of the local community and the ecosystems should take into account a concerted and integrated approach. There is an urgent need by communities, scientists and policymakers to take a closer look at the linkages between local impacts, scientific research, policy interventions and the larger understanding of using resource conservation technologies and practices for promoting societal benefits.
Way Forward:
Science has provided evidence of changes happening in the glaciers, but probably not very accurately as there is inadequate recorded historical evidence. However, the growing body of anecdotal evidence and observations of the communities provide evidence of how communities are coping and managing with change. This needs to be supported with science and observed data.
This study has provided data and information of the ground level parameters. In our view, this aligns with the growing emphasis on regional cooperation between Himalayan countries on the impacts of glacial retreat, as well as the national focus within India on the Himalayan ecosystems.