Storehouse of water
although the importance of Himalaya-Karakoram as the largest storehouse of fresh water in the lower latitudes, and the important role of their snow and ice in maintaining the flows of the Indus, the Ganga and the Brahmaputra during the lean period was well perceived and understood since ancient times, scientific understanding of the hydrology of the Himalaya-Karakoram has been seriously lacking. Because of the high costs and problems of logistics too, sustained programmes for scientific studies on the snow and glacier hydrology of the Himalayas are still lacking in most of the Himalaya-Karakoram countries.
In many cases, where some scientific studies have been undertaken, they are found to be of limited duration and are mostly carried out by glaciologists from countries outside the region in collaboration with national institutions. The glaciological research undertaken by the Japanese scientists in Nepal and those carried out by the Canadian and the British scientists in Karakoram, Pakistan are such examples. India and China have, however, initiated more sustained glaciological research in the region. Most of the scientific research and studies in Himalayan glaciers have been carried out only since the early 70's.
Publications emerging out of such studies in various countries of the Himalaya-Karakoram are not easily shared or are published in journals which are not always within the reach of researchers from the region. Furthermore, the Himalaya-Karakoram also contain areas of territorial conflicts which has hindered the free exchange of scientific knowledge and information on Himalayan glaciers in the region. Thus stimulus for research on Himalayan glaciers has been lacking.
Recently, decrease in snow cover area and accelerated retreat of glaciers due to the impact of global warming have been reported from all the countries in the Himalaya-Karakoram. These will have serious consequences on the lean period flow regimes of the Indus, the Ganga and the Brahmaputra as well as their tributaries.
The alarming rate of glacial wasting in the region in recent years clearly indicates the importance of intensifying research to improve our understanding of the complexity of glacial hydrology of the Himalaya-Karakoram region. This will enable us to plan with better confidence sustainable management of water resources in the regional countries, whether for meeting the individual or the collective needs of the future.
The publication of this book on Himalayan glaciers by Syed Iqbal Hasnain, who is widely known for his pioneering works in hydrochemistry of Himalayan glaciers in India is, therefore, very timely. This fills a long standing gap of a book on Himalayan glaciers and will certainly provide necessary stimulus to all students and researchers in this field, both within and outside the Himalayan-Karakoram region.
This book, which is based on the author's own work as well as those carried out by various researchers in India, Nepal and Pakistan contains 234 pages, divided into seven chapters, two appendices and a bibliography with 314 references. The first chapter provides an excellent introduction to the Himalayan glaciers, in terms of their importance as sustainable sources of water and provides a history of glaciological research in the Himalaya-Karakoram countries. The important relationship between climate and glacier in the region, glacier types, and the important characteristics of Himalayan glaciers where both accumulation and ablation occur in summer in contradistinction to the glaciers in the temperate world, which have distinct accumulation and ablation periods, is well explained. This chapter also provides facts and figures on retreat of Himalayan glaciers both in the past as well as in recent years and discusses the gravity of the problem in view of the possible impacts of global warming.
The second chapter deals with glacial hydrology and provides further details on the types and characteristics of Himalayan glaciers. It also discusses the flow regimes of the Indus and the Ganga on the basis of two hydrologic models, one for Karakoram and another for Garhwal Himalaya.
Chapter 3 is devoted to glacial hydrochemistry which introduces the subject with rich data and excellent details based on author's work in the Garhwal Himalaya.
Chapter 4 deals with hydrograph separation based on electrical conductivity. It also describes methods for the measurement of electrical conductivity with examples from Dokraini Glacier.
Sediment transfer processes in glacierised basins is discussed in Chapter 5. It talks of erosion processes and mechanisms and also describes some methods for erosion estimation. It also provides good discourse on processes governing sediment generation and transfer in glacierised basins but mostly based on studies in the temperate regions of Europe.
Sediment production, transport and deposition in glacierised regions is dealt with in Chapter 6. This chapter also highlights the importance of constructing a glaciofluvial sediment budget for river basins, which is indeed a difficult and complex problem in Himalayan rivers.
It also discusses principal features and mechanisms of sediment transport with examples from Batura Glacier (Karakoram) and Dokriani Glacier (Garhwal).
Chapter 7 deals with glacier lakes and their outburst floods. This is an important and new topic for Himalayan-Karakoram region as increasing number of glaciers and outburst floods are reported from various countries of the region and are considered to be the evidences of direct impact of global warming. This chapter also provides useful details on glacial lake outburst flood ( glof ) events in the Karakoram, Indian Himalaya and Nepal Himalaya.
There are two appendices after Chapter 7. Appendix i describes methods and instruments for the measurement of glacial meltwater. However, references for various methods and instruments which would have been very useful are unfortunately missing.
Appendix ii provides details on methods for the measurement of suspended load which are important and useful for estimating the rates of sedimentation in the reservoirs and lakes along glacier fed rivers. This is very useful as high sedimentation in the reservoirs is a major problem in the region.
The bibliography contains 314 references out of which 82 refer to the studies undertaken by national or international research teams in the Himalaya-Karakoram region. This clearly shows that bulk of material discussed in the book is based on works carried out in other parts of the world, mainly from Europe. Of the 82 studies cited from the regional countries, 40 refer to India, 20 to Nepal, nine to Pakistan, one to China and 12 to the region in general.
Each chapter starts with the introduction of the topic and then discusses major elements of the topics, methods of measurement and calculation of relevant parameters with examples based on data and results of work carried out in India, Nepal and Pakistan with comparison from similar or relevant studies carried out in other parts of the world, wherever possible.
This book will be an invaluable guide to every researcher and student of the hydrology and hydrochemistry of Himalayan glaciers. It will also be equally useful for planners who are interested in the sustainable development of water resources in the changing climates of Himalaya-Karakoram region.
The book also has its weak points such as incomplete sentences, repetition of some statements and tables, figures and diagrams without due reference to the sources which are found here and there could have been easily avoided through careful editing.
It is hoped that these will be taken care of in the next edition. However, the usefulness of this book and timeliness of its publication for outweighs such minor omissions.