Seventy Years of Exploration in Oceanography (eBook)

Foreword – Carl Wunsch 5
Foreword – Paul Gaffney 8
Preface 11
Acknowledgements 18
Contents 19
Acronyms 21
1 Waves and Wave Spectra 23
1.1 Oceanographers Learn About Power Spectra 23
1.2 Wave Prediction 25
1.3 Where the Swell Begins 28
2 Coming to America 33
2.1 Coming to America 35
2.2 Caltech 39
2.3 Serving in the Army 42
2.4 Clearance Problems 43
3 Bikini (1946) and Eniwetok (1951) 46
4 Settling Down at Scripps 53
4.1 Munk Finally Gets His Degree 53
4.2 Wind-Driven Ocean Circulation 54
5 From Waves to Tides 1958–1968 55
6 Deep Sea Tides 1964–2000 58
6.1 The Alleged Suicide of Aristotle 62
7 Internal Waves 1971–1981 65
8 Ocean Acoustics 1974–Present 69
8.1 The Gulf Stream Sheds Eddies 71
8.2 The MODE Experiments 72
8.3 Ocean Acoustic Tomography 72
8.4 Heard Island 75
8.5 Whales 80
8.6 The Last Twenty Years 81
9 Mohole 1957–1964 85
10 The Wobbling Earth 1950–1960 89
11 Institute of Geophysics and Planetary Physics (IGPP) 1962–Present 93
11.1 The Cambridge Connection 93
11.2 Finding the Faculty 98
11.3 Building the Laboratory 100
12 Navy 108
13 Finis 115
14 Epilogue 119
Appendix A: Curriculum Vitae 120
Appendix B: Bibliography 123
Index 149

"Chapter 1 Waves and Wave Spectra (p. 1-2)

1.1 Oceanographers Learn About Power Spectra

Hasselmann: Many of the topics you spearheaded in oceanography and geophysics were driven by your knowledge of time-series analysis, of spectral analysis and so forth. You were one of the first people to develop a general spectral analysis program, the BOMM (Bullard, Oglebay, Munk, and Miller) system [91]. And you applied that program to explore the ocean wave spectrum. Could you say a few words how you came to become interested in applying these spectral analysis techniques to oceanographic phenomena?

Munk: I first became aware of the problem in connection with wave prediction. During the war a remarkable UK group under George Deacon (later Sir George) had developed an analogmethod of getting power spectra for waves. Norman Barber from New Zealand did the pioneering work. He recorded on a film half black half white, with a wavy boundary that represented the wave record. The film was viewed through a vertical slit by a photocell whose output was the fraction of white film (the wave elevation). The film was mounted on a spinning wheel that was allowed to slow down by friction. The output of the photocell through a resonant RLCcircuit was recorded on paper. So as the wheel spun down, lower frequencies got into resonance. These were the first power spectra of ocean processes.

Hasselmann: I find this hard to believe. The acousticians knew about power spectra long before then.

Munk: Indeed they did. So did the optical people. They were monitoring in frequency space (pitch and color) in the first place. But I believe there was not a single oceanographer that knew how to handle time series of random phase processes. There were a few clumsy attempts to apply tidal analysis to represent wave records by a few fixed-phase frequencies.

We oceanographers depended on Barber’s wheel to lift the low wave frequencies of order 0.1Hz by four order of magnitudes to the 1000Hz resonant frequencies of RLC-circuits. But we were not the only ones who could not handle phase-incoherent processes. Meteorologists were in the same boat. So were seismologists, as we learned rather painfully during the test ban negotiations. So were geologists. But for the geologists random phase wave analysis was not such a useful tool (unless you think of ripples on the sea bottom). It is not fruitful to think of Yosemite’s Half Dome as a randomphase process."