Glaciers 1990–1995
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FLUCTUATIONS OF GLACIERS 1990–1995 (Vol. VII) A contribution to the Global Environment Monitoring Service (GEMS) and the International Hydrological Programme (IHP) Prepared by the World Glacier Monitoring Service (WGMS) IAHS (ICSI) – UNEP – UNESCO 1998 FLUCTUATIONS OF GLACIERS 1990–1995 with addendas from earlier years This publication was made possible by support and funds from the Federation of Astronomical and Geophysical Data Analysis Services (FAGS) the Swiss Academy of Sciences (SAS) the University of Zurich (UNIZ) the Federal Institute of Technology (ETH) Zurich This volume continues the earlier works published under the titles FLUCTUATIONS OF GLACIERS 1959–1965 Paris, IAHS – UNESCO, 1967 FLUCTUATIONS OF GLACIERS 1965–1970 Paris, IAHS – UNESCO, 1973 FLUCTUATIONS OF GLACIERS 1970–1975 Paris, IAHS – UNESCO, 1977 FLUCTUATIONS OF GLACIERS 1975–1980 Paris, IAHS – UNESCO, 1985 FLUCTUATIONS OF GLACIERS 1980–1985 Paris, IAHS – UNESCO, 1988 FLUCTUATIONS OF GLACIERS 1985–1990 Paris, IAHS – UNESCO, 1993 FLUCTUATIONS OF GLACIERS 1990–1995 (Vol. VII) A contribution to the Global Environment Monitoring Service (GEMS) and the International Hydrological Programme Compiled for the World Glacier Monitoring Service by Wilfried Haeberli1), Martin Hoelzle1,2), Stephan Suter2) and Regula Frauenfelder1) 1)Department of Geography University of Zurich Zurich and 2)Laboratory of Hydraulics, Hydrology and Glaciology Swiss Federal Institute of Technology (ETH) Zurich International Association of Hydrological Sciences (International Commission on Snow and Ice) and United Nations Environment Programme and United Nations Educational, Scientific and Cultural Organization 1998 Published jointly by the International Association of Hydrological Sciences, IAHS Press, Institute of Hydrology, Wallingford, Oxfordshire 0X10 8BB, UK and the United Nations Environment Programme P.O. Box 30552, Nairobi, Kenya and the United Nations Educational, Scientific and Cultural Organization 7 Place de Fontenoy, 75700 Paris, France Printed by Druckerei Flawil AG Flawil, Switzerland The designations employed and the presentation of the material in this publication do not imply the expression of any opinion what- soever on the part of the publishers concerning the legal status of any country or territory, or of its authorities, or concerning the frontiers of any country or territory. For bibliographic and reference purposes this publication should be referred to as: IAHS/UNESCO (1998). Fluctuations of Glaciers 1990–1995. Volume VII, Zurich: World Glacier Monitoring Service. IAHS UNEP UNESCO PREFACE Following the recent Second IPCC Assessment, there has been an escalation in publicity concerning the potential impacts of climate variability and change on the environment. Particular attention has been given to the consequences of climate change on society, especially within the framework of socio-economies. A fundamental societal need is an abundant supply of high quality water. It is now acknowledged within international circles that ‘water’ will be the critical issue of the 21st century, due to various socio- economic pressures arising from the global increase in population. The prospect of climate variability and change will only enhance further pressures on the diminishing, potable water resources. Thus it is critical to water resources management to have the necessary instruments for predicting and detecting climate change. Monitoring of the changes in glacier mass balances provides a very sensitive detector of natural and anthropogenic-induced climate variability which complement predictions from General Circulation Models (GCMs). Should significant climate change take place in the long term, the resulting glacier fluctuations will have major impacts both on river regimes downstream and on water resources management. Such aspects are of particular relevance to the continued implementation of the Fifth Phase of UNESCO’s Interna- tional Hydrological Programme. Consequently, the publication of Volume VII, 1990–1995, within the Fluctuation of Glaciers series is a timely contribution to the climate change issue. Furthermore this work complements the recent publication of the UNESCO Studies & Reports in Hydrology Series no. 57, entitled Into the 2nd Century of World Glacier Monitoring: Prospects and Strategies, and the earlier release of Glacier Mass Balance Bulletin No. 4 (1994–1995). All these publications have been in co-ordi- nation with the International Commission on Snow and Ice (ICSI) which assists the IHP-V with the implementation of project 1.3, “Hydrological interpretation of global change predictions”. The present Fluctuation of Glaciers volume is also a significant contribution towards The Second International Conference on Climate and Water, Espoo, Finland, August 1998. There are several important messages to the climate change communit found in this vol- ume. Foremost is that mass balances from 33 glaciers reflects continued glacier melting at an accelerated rate. The mean specific net balance (-287 mm) of the corresponding ref- erence glaciers for the five years 1990/91–1994/95 corresponds to an additional energy flux (2–3 Wm-2). It is considered that this flux corresponds to the estimated an- thropogenic greenhouse forcing and is slightly higher than the decadal mean of 1980–1990 (-277 mm). These means are, however, strongly influenced by the bias in geo- graphic-weighting towards Alpine and Scandinavian glaciers within the basic network. In that regard, it is appropriate to highlight the recent ICSI initiative in organizing a sym- posium on Glaciers in the Southern Hemisphere, Melbourne, July 1997, and a corre- sponding monograph which will be published shortly. Especially pertinent, the contents of the present book also remind us that natural climate variability is also capable of producing dramatic changes when concerning the European alpine glaciers, there was a near 50% reduction in total glacier volume from 1850 to the mid-1970s. Most of this change took place during the second half of the 19th century and the first half of the 20th century during times of relatively weak anthropogenic forcing. Filtering the effects of I natural climate variability from those attributed to anthropogenic influences poses one of the principal challenges to the global change scientific community. The World Glacier Monitoring Service is once again to be congratulated for continuing its efforts in producing this seventh volume in the Fluctuation of Glaciers series under the guidance and persistent efforts of Wilfried Haeberli and his collaborators. M. Bonell Chief, Section on Hydrological Processes & Climate International Hydrological Programme, UNESCO II FOREWORD Volume VII of the series of publications on the Fluctuations of Glaciers prepared by the World Glacier Monitoring Service covers a period of unprecedented interest in the mass balance of glaciers. As the general public wake up to the possibility of significant anthropogenic climate change within decades, they have realized that small glaciers are sensitive indicators of present climatic trends. The wasting away of the local glacier brings home the impact of climate warming to many non-scientists in a very vivid way. They want to know more – as do the world leaders who have to make difficult decisions balancing economic and environmental considerations . The information gathered for this publication allows scientists to give a balanced report of the health of glaciers world-wide. Those we know about are melting at an accelerating rate (except in parts of Scandinavia) and their meltwater makes an ever-greater contribu- tion to sea-level rise. However, there are many parts of the world where far too few gla- ciers are monitored. Over the last five years glaciologists have developed improved meth- ods of deducing the mass balance of unmeasured glaciers, often using data provided by the WGMS to test and improve their modelling techniques. In this way the predictions of the effects of climate change on glaciers world-wide are improved. The WGMS is to be congratulated on the production of this volume, which makes data from all over the world available to the glaciological community. The printed maps and tables complement data held in electronic form which, we must remember, is not always easily accessible for some researchers. Above all the efforts of the WGMS to ensure that valuable data are collected centrally has a stimulating effect on the community and en- courages the field scientist to continue with the important, but sometimes lonely task of collecting glacier fluctuation data. The work of the WGMS continues the long tradition of glacier monitoring which began in 1894. It is supported enthusiastically by ICSI (The International Commission on Snow and Ice) and we congratulate Professor Haeberli on bringing another volume in the valu- able Fluctuations of Glaciers series to publication. M. Kuhn E. M. Morris President, ICSI 1991–1995 President, ICSI 1995–2001 III IV PRELIMINARY REMARKS AND THANKS The present Volume VII of the “Fluctuations of Glaciers” mainly concerns the time peri- od from 1990 to 1995. It was prepared by the World Glacier Monitoring Service (WGMS) and continues the corresponding series of publications which contain internationally collected, standardized data on current changes in glaciers throughout the world, i.e.: Vol. I : Fluctuations of Glaciers 1959–1965 (P. Kasser) Vol. II : Fluctuations of Glaciers 1965–1970 (P. Kasser) Vol. III : Fluctuations of Glaciers 1970–1975 (F. Müller) Vol. IV