FROZEN ANNALS Greenland Ice Cap Research © Copyright 2005 by the Niels Bohr Institute, Copenhagen, Denmark 40112_001-068_frozen_web_2k 1 20/05/05, 11:55:52 © Copyright 2005 by the Niels Bohr Institute, Copenhagen, Denmark 40112_001-068_frozen_web_2k 2 20/05/05, 11:55:56 W. Dansgaard Frozen Annals Greenland Ice Cap Research © Copyright 2005 by the Niels Bohr Institute, Copenhagen, Denmark 40112_001-068_frozen_web_2k 3 20/05/05, 11:55:56 Edited by The Department of Geophysics of The Niels Bohr Institute for Astronomy, Physics and Geophysics at The University of Copenhagen, Denmark. e-mail: [email protected] Cover The Eqip Sermia, 1968. Photo by the author. Produced by Narayana Press, Odder, Denmark Printed 2004 by Narayana Press, www.narayanapress.dk Supported by The Aage V. Jensen Foundations © W. Dansgaard and the Editor. All rights reserved. ISBN: 87-990078-0-0 Dedicated to The Glaciological Group at the Niels Bohr Institute © Copyright 2005 by the Niels Bohr Institute, Copenhagen, Denmark 40112_001-068_frozen_web_2k 4 20/05/05, 11:55:56 CONTENT Preface . 7 6. The deep ice core. 54 Ice core analyses . 54 1. Approaching Greenland . 9 Time scales . 56 Some memorable years in Greenland . 9 A remarkable d-profi le . 57 The Greenland ice cap . 10 Up-stream and down-hole studies . 58 Early ice cap studies . 10 Retrieving a vanished bore hole . 60 A beginning . 11 Greenland – Antarctica . 63 Isotope meteorology . 12 Heaven and sea . 14 7. Dye 3 1973 . 64 What about the Climate? . 15 The snake pit. 64 Climate archives . 16 Daily life . 66 U.S.A. 16 Intermediate drilling . 66 2. The Bubble Expedition 1958. 18 8. Potential drill sites – GISP . 69 Playing dolphins . 19 North Site . 69 Butting and cooking icebergs. 21 Milcent and Crête . 70 Grounding . 22 Vostok . 71 Meeting Greenlanders . 22 Bela Papp . 73 The home voyage. 23 Results . 26 9. New aids, methods La Jolla. 28 and perspectives . 75 Automatization . 75 3. E.G.I.G. 1959-67 . 30 Position-fi xing. 75 Steering Committee meetings . 32 The “Rolls Royce drill” . 76 The EGIG poles . 34 The Hans Tavsen ice cap . 77 Eqip Sermia . 34 Renland . 78 The fi rst isotope climate record . 36 Inclusions in the ice . 78 4. The IAEA-WMO Dust and nitrate . 79 Acidity and volcanism . 79 network 1960-73 . 38 Complications . 39 10. ISTUK 1978-81 . 83 Expensive accommodation. 39 Journeyman’s certifi cate . 86 Results . 41 Turning point 1980 . 86 5. Camp Century 1964 . 43 11. Dye 3 results . 91 Swings . 44 Bore hole studies . 91 The nuclear reactor. 45 Ice core analyses . 93 Visiting Camp Century . 45 The end of the glaciation. 95 Diary notes . 46 The origin of Arctic precipitation . 96 The Iceworm . 52 The end of GISP . 96 Silicon-32 dating . 53 © Copyright 2005 by the Niels Bohr Institute, Copenhagen, Denmark 40112_001-068_frozen_web_2k 5 20/05/05, 11:55:57 6 Content 12. GRIP 1988-92 . 98 14. North GRIP 1996-2003 . 111 Eurocore . 98 Myriads of data . 112 The GRIP embryo. 98 The NGRIP drilling . 113 The GRIP Operation Centre . 98 2003 . 113 The Summit fi eld camp . 99 How far back? . 117 The GRIP economy . 103 Future climates . 119 Visitors . 103 Frozen Annals . 119 The GISP2 camp . 103 A medivac . 104 15. Selected references . 120 Triumph . 105 13. GRIP results. 106 The post-glacial period . 107 A tripartite Eem? . 108 © Copyright 2005 by the Niels Bohr Institute, Copenhagen, Denmark 40112_001-068_frozen_web_2k 6 20/05/05, 11:55:58 PREFACE This book does not pretend to be a strict scien- and J. Kipfstuhl (Germany), David Peel and Eric tific review. It rather aims to be a readable story Wolff (Great Britain), Preben Gudmandsen and primarily about some Danish contributions to through half a cen tury, Henrik Tauber (Copen- the exploration of the Greenland ice cap. hagen), who recently improved this manuscript Prior to World War II most ice cap research considerably. rested on relatively simple techniques applied by Throughout the years we enjoyed a close, daring Polar explorers. The civilian post-war re- competent and fair logistic co-operation with search was marked by international co-operation The Royal Danish Air Force and The US Air and logistical progress (reliable surface and air Force, New York National Guard, 109’ TAG transport), as well as new analytical and drilling (Tactical Air Group). techniques. For example, in the 1950’es some Some of the figures in this book are repro- seeds of stable isotope meteorology were sowed at duced from dias kindly put at my disposal by the University of Copenhagen, and from the late Lars Berg Larsen, Ivars Silis, J.P. Steffensen, 1960’es they developed into extensive studies of and The Danish Polar Center. Greenland ice cores, originally in co-operation Financially, the Danish part of the work with USA CRREL (Cold Regions Research and was supported by former Minister of Research Engineering Laboratories). Bertel Haarder, by The University of Copen- The enthusiasm and versatility of all my Dan- hagen, and by several foundations, particularly ish colleagues, scientists and technicians, in the The Carlsberg Foundation, The Commission laboratory and in the field, made our group an for Scientifi c Research in Greenland, and The attractive partner for major foreign institutions, Danish Natural Science Research Council. I American, European and Japanese. thank them all sincerely. Most of our Greenland research has been In the text, references to the list of selected executed as joint efforts by up to 11 nations, background papers p. 120-122 are indicated by and, we are deeply indebted to many “external” chapter and number in angular parentheses. scientists, who contributed materially to our Annotations (passing remarks on techniques, common achievements. This applies particu- digressions, definitions, and a few complex topics larly to Chester C. Langway Jr., Lyle B. Hansen, of secondary importance) are put in blue “boxes” and Jim W.C. White (U.S.A.), Hans Oesch ger, that may be skipped without disturbing the prin- Bernhard Stauffer, Jacob Schwander, and Henry cipal line in the text. Rufli (Switzerland), Jean Jouzel and Laurent Augustin (France), David Fisher (Canada), January 2004, Margareta Hansson (Sweden), Okitsugu Wa- Willi Dansgaard tanabe and Hitoshi Shoji (Japan), Heinz Miller © Copyright 2005 by the Niels Bohr Institute, Copenhagen, Denmark 40112_001-068_frozen_web_2k 7 20/05/05, 11:55:59 © Copyright 2005 by the Niels Bohr Institute, Copenhagen, Denmark 40112_001-068_frozen_web_2k 8 20/05/05, 11:56:00 1. APPROACHING GREENLAND In the far northwesterly corner of the Atlantic paid in cryolite, a mineral of great importance Ocean lies Kalaallit Nunaat, the land of man, as for the production of aluminum. This opened the Greenland is called by the Inuits. From a distance Greenland gate ajar to the outside world. Even- this largest island in the world looks like a white tually, the gate was fully opened to a completely jewel set in dark mountains. And behind the new life implying education on all levels and mountains lies the inland ice, barren and wide, build-up of trades and industries supplement- cold and white, a temptation to the adventurer, ing the traditional hunting and fishing, a social a challenge to the searcher, ruthless to the rash, quantum leap unmatched in depth, extent and generous to the seeking. Deep silence inland, pace anywhere in the world. interrupted by howling blizzards over the endless Since 1979, Greenland has had local au- monotony of the snow-sheet, and roaring drama tonomy executed by a Home Rule within the along the edges, when icebergs calve from the framework of the Kingdom of Denmark. glaciers, or foaming rivers plunge into the sea. This is the impression of the Greenland nat- ure that emerges from Knud Rasmussen’s leg- endary research among the Eskimoes, reports on explorer’s struggle for life in the wilderness of Northeast Greenland, and Peter Freuchen’s wonderful polar stories. Personally, I had no ambition of being a polar hero, neither did I become one. But I did experience the heroes’ wonderful world, and I managed to contribute a bit to its exploration. Some memorable years in Greenland Greenland has been inhabited by Inuits (Es- kimoes) intermittently through the last more than 4000 years, and permanently since about 500 A.D. The first European settlement was founded by Erik the Red in 985 A.D. and lasted till some time in the 15’th century, when the Norsemen society died out for unknown rea- sons. Only 300 years later, in 1721 A.D., the Dan- ish-Norwegian priest Hans Egede, founded Godthåb (now Nuuk). Until 1950 A.D., an agency under the Danish Government admin- istered Greenland with the chief aims of (1) providing the Greenlanders with goods needed to sustain a primitive life based on local seal- ing, whaling and fishing, and (2) protecting the Greenlanders against the “destructive trends” in the modern world. However, during the Second World War sup- plies of goods were imported from U.S.A. and Fig. 1.1 Greenland and its ice cap © Copyright 2005 by the Niels Bohr Institute, Copenhagen, Denmark 40112_001-068_frozen_web_2k 9 20/05/05, 11:56:00 10 Approaching Greenland The Greenland ice cap Wegener studied the weather conditions 50 % of all fresh water on Earth outside Antarc- throughout the winter, and inside the hut they tica is bound as ice in Greenland. The ice cap drilled to a depth of 25 metres by an auger not covers 85 % of the total 2.2 mill. km2 area of unlike an oversized corkscrew. They measured Greenland (Fig.1.1). It measures 2500 km from the temperature at various depths and its vari- north to south and about 750 km from west to ation throughout the winter.