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The microscopic dimension of paleoclimate in the EPICA-DML(Antarctica) deep ice core Dissertation zur Erlangung des Doktorgrades der Mathematisch-Naturwissenschaftlichen Fakultäten der Georg-August-Universität zu Göttingen vorgelegt von Aneta Florentina Nedelcu aus Bucureşti, Romania Göttingen, 2011 D 7 Referent: Prof. Dr. W. F. Kuhs Koreferent: Prof. Dr. G. Wörner Koreferent: Dr. S. H. Faria Tag der mündlichen Prüfung: Dedicated to YOU* my dear Reader What would my humble work be without YOU? * if I am to name a Muse, then the dedication should read: 1 for Barιş “Der Wahre Türke”, who takes all the gratitude for the kindest, warmest and most magnificent “Hallo” “A-nceput de ieri să cadă The snowflakes started from yesterday, Câte-un fulg, acum a stat, One by one to fall down way. Norii s-au mai răzbunat Now the clouds are a bit lighter Spre apus, dar stau grămadă On the north side, but still gather’ Peste sat.” All over the village. George Coşbuc / Romanian writer “Iarna pe Uliţă” / “Winter on the village’s road” (~1886) 1 nice to know that the English translation of this name is Peace The Romantic Introduction. A Personal Motivation from some of the 21.November.2007 notes: My dear Reader […] my personal inner feeling related with all the thousands words You will read in this incomplete and imperfect thesis……. […] it’s really very hard to describe the beauty of the natural phenomenon which generated my interest for the project and even the project itself. If You didn’t guess yet I have in mind the memory of billions and billions of Snowflakes dancing downwards from the Sky to the freshly frozen Earth. As You can see some plain and extremely usual words can not make You feel anything special though nothing compares with (ok if You are an astronaut I agree that the Earth seen from outer space might be as beautiful as the Winter’s ballerinas). Every year I wait eagerly for the first Snow of the Winter, just for that sublime unbelievable feeling one gets when the wonders of the Winter enter on the season’s stage. The problem is that from a year to another the Snowflakes choose to come down from the Sky later and later extending my longing for seeing Them and making way for the grief and the fear expressed like: what if They will choose not to come down anymore? Well, nowadays scientists say They will not choose to disappear so soon. Maybe They will move from one place to another […] [like those] with billions and billions of Snowflakes transformed into silvery ice under Antarctic weather conditions […] ……… The Realistic Epilogue. A General Remark “Render unto Caesar the things which are Caesar’s, and unto God the things that are God’s” (Matthew, 22:21)1 The mind conquered the world; but the heart remaind unhappy; They regret what it was. The eyes saw all the beauty; but the ears heard the hell; They hope will’e off. The nostrils perceived the finest fragrance; but the mouth could not speak; They have no dreams. The wind so gentle; but the wings were broken; They rest asleep. The knowledge so vast; the universe so narrow; They were foolish. The wealth incommensurable; but the sorrow deepest; They were tyrants. The glory unfair; and the heroes unsung; They were not acclaimed. The smile in vain; the soul in pain. 21.February.2013 1“Pay no attention to Caesar. Caesar doesn't have the slightest idea what's really going on.” (from Vonnegut K., Cat's Cradle, Dell, N.Y., 1963, pg. 88) Summary “The story is always about searching the truth, no matter what might bring. Even when nothing was what it appeared to be, when everything was hidden, there was a center not even I could run from: who I truly was, what I felt, what I was deep inside.” (from The Ice Queen, A. Hoffman, pg. 165) The present work is divided into two main parts: the introductory half and the experimental chapter. Chapter 1 starts with the brief presentation of the scientific project that facilitated the development of the thesis, then presents a historical survey of the early expeditions towards and in Antarctica, just to reach to the basic geological aspects relevant for the second part of the work, and to end with some glaciological aspects worth of being noticed in the context of the thesis. The third section describes the basic Antarctic meteorology, focus on Dronning Maud Land region, while the forth subchapter tells only a few stories about the EPICA-DML ice core. The last part of Chapter 1 wanted to be a kind of ‘encyclopedia’ of what can be found as trapped in polar ice; it resulted in some useful but subjective base for the understanding and interpretation of the results presented in the second half of the thesis. Chapter 2 deals with the presentation of the original results after the employed methods are briefly described. Outcomes from optical microscopy investigations, a few SEM-EDX analyses, and mostly from the first Raman analyses on microinclusions existent in EDML ice, (included as Appendixes), lead to the following conclusions (Chapter 3): -secondary microinclusions developed in polar ice after its extraction, due to structure relaxation, contain fractionated air enriched in oxygen, O2 -the nitrogen to oxygen (N2/O2) ratio for the investigated relaxation microinclusions took values between 0.3 and 2 -microinclusions containing soluble salts, may exist as solids or as liquid solutions, if their eutectic temperature permits or if they are associated with other substances, like acids -hardly soluble microinclusions are mainly silicates and/or silica, and to a lesser degree Ti containing compounds and they are enriched in less clear ice (cloudy ice) -a number of microinclusions, which could have been formed in the polar atmosphere or in the firn/ice matrix, contain more than one compound (either two different sulfates or a Si compound and sulfate) -double sulfates of jarosite type composed few of the investigated microinclusions and they can be the result of diagenesis CONTENTS The Romantic Introduction. A Personal Motivation The Realistic Epilogue. A General Remark Summary 1. INTRODUCTORY PART........................................................................................................... 1 1.1 The EPICA project ................................................................................................................ 1 1.2 Terra Antártida ....................................................................................................................... 2 1.2.1 What’s in a name? What means Antarctica? .................................................................. 2 1.2.2 What is Antarctica? What is it made of? ........................................................................ 2 1.2.3 What about Man becoming aware of Antarctica’s existence? ........................................ 3 1.2.4 Antarctica’ general geology and the Dronning Maud Land region ................................ 5 1.2.5 What more about ‘snow-firn-ice from 66°S to 90°S’ ? .................................................. 6 1.3 The sky above the austral ice ............................................................................................... 10 1.3.1 The wind and temperature regime ................................................................................ 10 1.3.2 Atmospheric aerosol ..................................................................................................... 12 1.4 Kohnen Station 17.01.2006 ................................................................................................. 16 1.5 What is not ice can be trapped in (Antarctic) ice ................................................................. 22 1.5.1 Gaseous microinclusions in polar ice ........................................................................... 26 1.5.2 Liquid and solid microinclusions in polar ice ............................................................... 28 2. EXPERIMENTAL PART ......................................................................................................... 32 2.1 Methods ............................................................................................................................... 32 2.1.1 Optical microscopy ....................................................................................................... 33 2.1.2 SEM-EDX microscopy ................................................................................................. 39 2.1.3 Raman spectroscopy ..................................................................................................... 47 2.2 Original Results ................................................................................................................... 52 2.2.1 Oxygen enriched relaxation features in EDML ice ...................................................... 52 2.2.2 Chemistry of soluble and hardly soluble micro-inclusions in clear and cloudy MIS2 EDML ice .............................................................................................................................. 69 2.2.2.a Discussion : Qualitative results .................................................................................. 73 2.2.2.b Discussion : Frequency distribution of the microinclusions ...................................... 90 3. CONCLUSIONS ....................................................................................................................... 94 References ...................................................................................................................................... 97 Endnote .......................................................................................................................................
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