Shouraseni Sen Roy
Guest Lecturer, Miranda House.
University of Delhi, Delhi 110007
Extreme events can be defined as infrequent meteorological events that have a significant impact upon society or ecosystem at a particular place (Michael et al 1996). Extreme weather events can also be said to have taken place when there is wide departure from the average behaviour of weather. Comparatively small changes in climatic variability or mean climate can produce relatively large changes in the frequency of extreme weather events.
Mountains are home to a major portion of the earth’s diversity of species and ecosystems. It is also responsible for climatic phenomena in some places like the Himalayas. In fact this mountain range contributes greatly to the shaping of monsoon phenomena (Singh and Sen Roy, 2000). Environment of high mountain areas is greatly vulnerable to external disturbances such as anthropogenic interference. But the pressure of expanding economic activity mainly in the form of tourism and associated activities are degrading mountain ecosystem while confronting people in this area with rising levels of poverty, cultural assimilation. But the expanding pressure of economic activity mainly in the form of tourism and associated activities are degrading mountain ecosystem while confronting people in this area with rising levels of poverty, cultural assimilation and political dis-empowerment. The positive effects of tourism are in the form of preservation of physical features, cultural heritages and natural flora and fauna. On the other hand the negative effects are congestion, deterioration of aesthetic grandeur and unscrupulous replacement of natural landscape, unplanned haphazard built up areas. In the mountainous areas diverse relief and slope further increase both temporal and spatial variability. Mountainous regions are characterized by sensitive ecosystems, enhanced occurrences of extreme weather events and natural catastrophes. They are also regions of conflicting interests between economic development and environmental conservation. Most of the mountainous regions have been undergoing rapid developmental changes in the form of unplanned and haphazard urbanization. This appears to have led to an increase in the frequency and intensity of the various forms of extreme weather events, which are mainly in the form of soil erosion, landslides, avalanches, solifluction, and flashfloods.
Analysis of the various extreme events taking place in the district is a result of combined interaction between anthropogenic and natural causes. Off late the role of anthropogenic factors is becoming more pronounced resulting in an increase in the frequency of various extreme weather events. The resulting loss of life and damage to property can be reduced with proper planning and implementation of preventive measures. A multidisciplinary approach combining various professionals in policy formulation and providing data bases facilitating decisions at the level of policy makers is needed to minimise the loss due to extreme weather events.
It is in this regard that one of the vital steps to be taken towards the mitigation and preparedness of extreme weather events is the maintenance of an up to date extensive GIS database. An extensive spatio-temporal database should b maintained at the micro level. This is possible by a thorough field stud supplemented by satellite imageries for mapping the flood extent, landslides impacts and the status of vegetation cover prevailing over an area. Hazard risk zonation should be done for the critical areas to begin with, which can be extended later to the entire region. Separate layers should be prepared to indicate the probability of a particular kind of hazards. The next step will be to overlay all the hazard maps seamlessly and then identify the most critical zones of the region. With the help of such spatial analysis all future developmental ventures can be planned out.
Thus it will have to be borne in mind that the environment has a very special and delicate relation with all its components including human beings. In this regard hazard risk zonation maps can be a great step forward in proper planning of economic activities in those area and prevention of hazard related disaster resulting in climatic extremes.
- Mc Michael, A.J., Haines, A., et al. (1996) Climate Change and Human Health, World Health Organisation, Geneva.
- Singh, R.B and Sen Roy, S. (2000) “Impact of Climate Variability on Agriculture, Horticulture and Extreme Events” Paper presented in CIDA-SICI project Dissemination workshop on Urban Development and Environmental Impacts in a Mountain Context, Delhi.