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24 January 2006−−Sir Nicholas John Shackleton. 23 June 1937
Ian Nicholas McCave and Henry Elderfield
originally published online June 29, 2011, 435-462, published 29
June 2011572011 Biogr. Mems Fell. R. Soc.
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Sir NicholaS JohN ShackletoN23 June 1937 — 24 January 2006
Biogr. Mems Fell. R. Soc. 57, 435–462 (2011)
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Sir NicholaS JohN ShackletoN
23 June 1937 — 24 January 2006
elected FrS 1985
By Ian nIcholas Mccave and henry elderfIeld frs
Godwin Laboratory for Palaeoclimate Research, Department of
Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK
Nick Shackleton was an international scientist of great renown
who fundamentally changed our understanding of how earth processes
work. his research on ancient oceans and climates was both
innovative and pioneering, and he clarified the precise role of
carbon dioxide in warming and cooling the earth’s climate. his work
contributed greatly to our present under-standing of the mechanism
and causes of global warming. When he began his research, the
investigation of past climatic changes was an area of ‘academic’
interest only. Four decades later, his lifetime achievements define
the emergence of our understanding of the operation of earth’s
natural climate system. this understanding of the past is now
central to efforts to predict the future climate we have begun to
create. as well as his many scientific accomplish-ments, Nick
Shackleton excelled in another area, that of music, which was
almost as important to him as science, and he was a very
accomplished clarinet player. in his work he was spirited and
curiosity-driven. he let his students and an entire community share
in his brilliance and vision.
early lIfe, and lIfe at caMBrIdge
Nick Shackleton was born on 23 June 1937 at 112 cheyne Walk,
chelsea, london, the first of three children of robert Millner
Shackleton (FrS 1971), a field geologist, son of John Millner
Shackleton, an electrical engineer, and his wife Gwen isabel (née
harland) (divorced in 1949), daughter of alfred John harland, a
schoolmaster. he had a half-brother and half-sister by his father’s
second marriage (1949–78) to Gertrude (Judith) Wyndham Jeffreys
(1915–2000), and finally a second stepmother, geologist Dr Peigi
Wallace (1940–2001), on his father’s third marriage in 1984.
http://dx.doi.org/10.1098/rsbm.2011.0005 437 this publication is
© 2011 the royal Society
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438 Biographical Memoirs
he was a distant relative (his grandfather was a second cousin)
of the antarctic explorer Sir ernest Shackleton (1874–1922). he
married, first in 1967, Judith carola Murray, who was then an
undergraduate at Newnham college, daughter of the late henry
Murray, a chemist. they were divorced in 1977. in 1986 he married
Vivien anne law (1954–2002), a distin-guished linguistic scholar
(FBa) who knew more than 100 languages and who, he claimed, could
learn a new language reading a grammar over the breakfast table.
tragically, she died, like Nick, of cancer, at the height of her
powers, aged 49 years.
Nick’s father was a lecturer in geology at imperial college,
london, and later Professor of Geology at leeds University (where
he gave one of us (h. e.) his first job as a junior lecturer),
specializing in african, and later himalayan, geology. robert
Shackleton trav-elled widely for research and industry, spending
1940–45 in kenya searching for gold and strategic minerals, thereby
giving Nick an early childhood on the african plains, out of the
way of wartime london bombing. although his father was a
distinguished geologist, Nick credited his mother with encouraging
his scientific curiosity. as a young student, he often came home
from school with some new morsel he had learned. if his mother knew
some-thing about the subject, she would talk about it with him. if
not, she and Nick would search for more information.
he attended cranbrook School, kent, as a boarder pupil from 1949
to 1956, followed by National Service in the Queen’s own royal West
kent regiment, where, as Bandsman Shackleton (army no. 23313350)
and already an accomplished clarinettist, he was secretary of the
regimental band. he trained at catterick, and served in cyprus for
a while. he entered clare college, cambridge, in 1958 to read
Natural Sciences. he found several outlets for his enthusiasms,
including music and athletics. Perhaps as a consequence, his
undergraduate career was academically undistinguished. he was
placed in the second class in Part i Prelim, lower seconds in Part
i and Part ii, graduating Ba in physics in 1961. in the first two
years of his degree he split his time about equally between physics
and mathematics and, perhaps following his father, geology and
mineralogy. in his final year he specialized in physics for Part ii
of the Natural Sciences tripos.
an opportunIty arIses
on his graduation in 1961, what he later called ‘a series of
random events’ led to his follow-ing his father into the earth
sciences, but in a different direction. the random events were
associated with the suggestion, made in about 1960 by Sir edward
Bullard FrS, the head of Geodesy and Geophysics at cambridge
University, that harry (later Sir harry) Godwin FrS, then head of
the Sub-Department of Quaternary research (which was part of the
Botany Department, of which Godwin also was head), should set up a
laboratory in cambridge to measure stable isotopes. the reason for
Bullard’s suggestion related to the work of the Nobel laureate
harold Urey ForMemrS. in 1947 Urey had published calculations that
predicted that the heavy isotope of oxygen (18o) would be
fractionated from its light isotope (16o) as a function of
temperature (Urey 1947). Professor of Botany harry Godwin had
already set up a radiocarbon laboratory to make 14c age
measurements. in 1960, Bullard, at that time reader in Geophysics,
suggested that he add the determination of past temperature through
oxygen isotopes. it so happened that Godwin was a Fellow and
Bullard a member of clare college, where Shackleton was an
undergraduate. Nick was offered and accepted the task for his
PhD
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Nicholas John Shackleton 439
of setting up the oxygen isotope palaeotemperature method
(although that word had not then entered the scientific
vocabulary).
Urey had suggested that measurements of 18o/16o ratios would
provide a method of estimating temperatures in the geological past,
from analysis of fossil shells composed of calcium carbonate
minerals. he assembled a group of talented scientists who designed
a mass spectrometer to test his theory, and in the early 1950s they
demonstrated that it was correct. among this team was cesare
emiliani, who, because of his background in micropalaeontol-ogy
(the study of microscopic fossils), went on to apply the techniques
developed to micro-fossils called foraminifera recovered from
deep-sea cores. emiliani identified cycles of warm and cold sea
surface temperatures back to more than half a million years ago;
because of this work, emiliani is often thought of as the founder
of palaeoceanography.
the work carried out by emiliani was extremely laborious,
requiring a relatively large amount of material, and Shackleton
realized that, to set up a successful laboratory, he needed to
develop a mass spectrometer an order of magnitude more sensitive
than that developed by Urey’s team. Nick’s seminal effort was to
modify a mass spectrometer so that it could measure the mass ratio
of the isotopes of oxygen in minute samples of calcium carbonate
(1)*. Samples as small as 0.4 mg (representing about five to ten
shells of the pinhead-sized fossil foraminifera common in marine
sediments) could be measured to an accuracy of 1 part in 10
000.
he accomplished this as part of his thesis work and in 1967
received his PhD for a dis-sertation entitled ‘the measurement of
palaeotemperatures in the Quaternary era’. he applied his method to
make oxygen isotope measurements on shells of fossil foraminifera
that lived in bottom waters (benthic) and those from surface waters
(planktonic). From a comparison (figure 1), he saw a fatal flaw in
emiliani’s work. emiliani had interpreted his results on
plank-tonic foraminifera as an 8 °c change in surface temperature
from the last ice age to today. Shackleton found that the changes
in isotopic composition for benthic and planktonic spe-cies were
about the same (figure 1), yet for the deep sea this temperature
change was clearly impossible: the deep-sea water temperature today
is less than about 2 °c and the freezing point of sea water is
about −2 °c. the dominant cause of oxygen isotope variations was
not temperature, but changes in the oxygen isotope composition of
the oceans caused by removal of isotopically depleted water to form
the ice sheets. in a spirit that typified Shackleton’s gen-erosity
throughout his career he wrote in his Nature paper in 1967
reporting this crucial result in the year of his PhD (2):
it should be emphasised that the time sequence which emiliani
has been able to obtain … remains of inestimable value … in a sense
it is enhanced by the certainty that it is a time sequence for
terrestrial glacial events rather than oceanographic events.
in 1965, during the course of his PhD research, Nick was
appointed as Senior assistant in research (equivalent to a junior
lectureship, although he did little teaching) in the Sub-Department
of Quaternary research in the Department of Botany at cambridge
University, a position he held until 1972, when he became assistant
Director of research in the sub-department. in 1988 he was
appointed Director of the sub-department and, in 1995, Director of
what by then was called the Godwin institute of Quaternary
research, a post he held until 2004, when he retired. to add to the
complexities of cambridge appointments, he was elected
* Numbers in this form refer to the bibliography at the end of
the text.
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440 Biographical Memoirs
ad hominem reader, cambridge University, from 1987 to 1991, and
ad hominem Professor of Quaternary Palaeoclimatology from 1991 to
2004. he was also a research Fellow at clare hall, cambridge, from
1974 to 1980, and Fellow from 1980 to 2004.
glacIatIon
As we have outlined, the seminal realization that the record of
benthic δ18o (by which we mean the δ18O of benthic foraminiferal
calcite; δ18o is a measure of the 18o/16o ratio) was dominated by
ice volume had obvious consequences for the interpretation of
glacial events on the continents: the onset and waxing and waning
of ice sheets. clearly, also, more ice on land meant less water in
the sea and thus insights into the history of sea level. Nick’s key
associates in this work were Neil opdyke (lamont–Doherty Geological
observatory), Jim kennett (University of rhode island) and, for sea
level, John chappell (australian National University) (34). the
classic paper with opdyke (5) set out the arguments for a close
relation-ship between isotopic values, ice volume and sea level,
with a 1‰ shift in δ18o representing about 100 m (figure 2).
one might therefore see it as perverse that in 1975 Shackleton
and kennett (S&k) (8, 13) discovered and interpreted the
biggest shift in benthic δ18o in the past 50 million years (50 Ma),
occurring in the early oligocene, as having been solely due to
major cool-ing of bottom water rather than the presently accepted
view that it records the onset of antarctic glaciation plus bottom
water cooling (Miller et al. 1991; Zachos et al. 1993; lear et al.
2000). however, it must be remembered that at that time there was
no rigorous
Figure 1. oxygen isotopic composition of benthic (benthonic)
foraminifera from a caribbean Sea core plotted against oxygen
isotopic composition of planktonic foraminifera. Note that the
ranges in values of δ18o for planktonic species (abscissa) and
benthic species (ordinate) are both about 2‰. (reprinted from (2)
with permission from Macmillan Publishers ltd. copyright ©
2011.)
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Nicholas John Shackleton 441
method of separating the contributions of temperature and
seawater δ18O to benthic δ18o, which is now available through Mg/ca
palaeothermometry (lear et al. 2000). S&k (8) maintained that
the onset of antarctic glaciation came at the second isotopic step
in the mid-Miocene (figure 3). the S&k argument was based on
calculation of temperature by the equation that Shackleton had just
devised, which was valid for low temperatures found at the sea
floor (6):
T = 16.9 − 4.38(δ18oc − δ18ow) + 0.10(δ18oc − δ18ow)2,
where δ18oc = δ18O of foraminiferal carbonate and δ18ow = δ18o
of ocean water. the iso-topic composition of the ocean before the
formation of the present ice sheets was estimated at −1.2‰ (in
contrast with the modern value, −0.28‰) on the basis of the fact
that the ice now stored in antarctica is isotopically more
negative. S&k (8) also assumed ‘that there was insignificant
antarctic ice up to the … middle Miocene’, this assumption being
based on a further assumption that bottom waters would have
remained more or less constant from the time that the antarctic ice
sheet started to accumulate. it is clear from this and other papers
around that time that palaeoceanographers struggled to extract
palaeotemperatures that they knew were embedded in their
measurements of benthic δ18o. S&k (8) further justified their
approach with the complex (and difficult to decipher) argument
that
there is a trend to lower deep temperatures through the eocene,
culminating in a value of about 5 °c in the early oligocene. if the
value had not been corrected by assuming the absence of the
antarctic ice sheet, the value yielded at this point would have
corresponded to a temperature of about 9 °c. Such a value would of
course be incompatible with the presence of a major ice sheet
extending to the coast. thus the assumption that the ice sheet was
not present is strongly supported by observations.
Zachos et al. (1992, 1993) made a different assumption, namely
that deep water tem-peratures never fell below 1 °c, which puts a
lower limit on ice volume: when equilibrium δ18o values exceeded
2.4‰, continental ice must have existed. on that basis they
inferred
Figure 2. isotope records from core V28-238 (western equatorial
Pacific), showing similar amplitudes of both benthic and planktonic
foraminifera. this reflects mainly ice volume and hence sea level.
the two sequences are plot-ted to the same scale of isotopic change
but with scale zero-points differing by 5.3‰, the present-day
plank-tonic–benthic difference. (reprinted from (5) with permission
from elsevier. copyright © 2011.)
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442 Biographical Memoirs
(a)
(b)
Figure 3. (a) Detail from the isotopic record from late Eocene
to early Oligocene, showing a sharp increase in δ18o interpreted as
a large decrease in bottom temperature. (reprinted from (13) with
permission from Macmillan Publishers ltd. copyright © 2011.) (b)
From left to right: deep-sea temperatures based on Mg/ca,
compilation of δ18o (based on Miller et al. (1991)) and estimation
of seawater δ18o (lear et al. 2000), where the shift is seen as the
onset of major Southern hemisphere glaciation. (adapted from lear
et al. 2000; reprinted with permission from aaaS.) (online version
in colour.)
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Nicholas John Shackleton 443
glaciation—a transient ice sheet—in the early oligocene. the
palaeotemperature data of lear et al. (2000) confirm that most of
the benthic δ18o signal results from a build-up of continental ice
with little temperature response.
in the work with kennett on the New Zealand DSDP cores,
Shackleton also inferred the onset of major Northern hemisphere
glaciation at 2.6 Ma ago (9). this was later confirmed in the North
atlantic, where Shackleton and his colleagues dated (by isotopes,
magnetic revers-als and biostratigraphy) the first minor layers of
ice-rafted detritus at 2.5 Ma ago and full ice sheet delivery of
ice-rafted debris (irD) at 2.4 Ma ago (31). Further work with
kennett (7) on planktonic foraminifera in the Gulf of Mexico
provided the first inference from isotopic data of the presence of
meltwater from the Mississippi resulting from glacial retreat.
olausson (1965) had earlier given careful consideration to the
isotopic composition of ice sheets (aided by Willi Dansgaard, with
whom Shackleton shared the crafoord Prize) and concluded that (i)
emiliani’s Pacific data (emiliani 1955a) did not record a
significantly lower temperature in the Glacial and (ii) his
Mediterranean data (emiliani 1955b) showed that the ‘rapid and too
early rise in the isotopic temperature curve cannot be due to a
rapid warming of the ocean. it must be due to meltwater
contamination of the surface water.’ thus the principle of deducing
meltwater from isotopes was not new, but the history of laurentide
decay was.
clIMap and specMap
one application for this time sequence referred to above was to
identify isotopically the hor-izon of the last ice age in ocean
cores worldwide, which provided the temporal framework for a large
US-driven project in which Shackleton participated, called cliMaP
(climate: long-range investigation, Mapping, and Prediction). this
generated a global map of sea surface temperature, inferred from
foraminiferal abundances, at the last Glacial Maximum (lGM) (10,
22). the map was used by modellers to reconstruct atmospheric
circulation in glacial times and as a boundary condition in models
that explored changes in atmospheric tempera-ture, which were of
crucial importance for modelling future climate.
this set the stage for the most important application of the
oxygen isotope method: the reconstruction of the history of global
ice volume through the ice ages. Milutin Milankovitch in the 1920s
had hypothesized that ice ages were caused by changes in
distributions of solar radiation at the earth’s surface, which were
in turn driven by changes in movement of the earth’s orbit.
Shackleton and his US co-workers Jim hays (of the lamont–Doherty
Geological observatory of columbia University, where Shackleton was
appointed Senior Visiting research Fellow in 1974) and John imbrie
(of Brown University) generated long climate and isotopic records
from different ocean regions and subjected the patterns to
mathemati-cal (spectral) analysis. the result was the famous 1976
paper in Science (‘Variations in the earth’s orbit: pacemaker of
the ice ages’ (11)), where they showed that the three periodicities
with which the earth’s orbit changes (100 000 years, 40 000 years
and 21 000 years) were all present in the temperature, isotopic and
fossil records, just as predicted (figure 4).
assembly of more, longer and higher-resolution records now
became the focus of the suc-cessor project, SPecMaP (the Mapping
Spectral Variability in Global climate Project), which used a
stacked oxygen isotope stratigraphy and four different ‘orbital
tuning’ approaches. the resulting tuned chronology had an average
error of ±5000 years over a 300 ka record (35).
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444 Biographical Memoirs
this clear recognition of orbital control is also now
revolutionizing the whole of stratigra-phy (the study of geological
strata) because it provides in principle a means of correlating
beds at separated parts of the earth to a precision of 20 000 years
at a time of hundreds of millions of years ago, and of determining
precise ‘orbitally tuned’ age-calibrated stratigraphies back to
about 250 Ma ago (laskar et al. 2004).
orBItal tunIng of the pleIstocene tIMe scale and Its
consequences
Challenge to the primacy of radiometric datingin the early days
of isotope stratigraphy, potassium–argon dates on volcanic ash were
useful checks on the age of isotope stage boundaries, starting with
the marine isotope 5/4 stage bound-ary at about 75 ka ago. a key
method for correlation between cores is through the stratigraphic
record of earth’s magnetic reversals. once dated in volcanic ash
layers and piles of lava by
Figure 4. Spectra of variations in (a) orbital obliquity and
precession (Δe sin Π), (b) insolation at 60° N, (c) sea surface
temperature and (d) δ18o as a function of frequency (cycles per
thousand years). (c) and (d) are based on an analysis of two
sub-antarctic deep-sea cores. Note the excellent match between
orbital and climatic variables and the strong presence of a peak
with a period of about 100 ka. insolation variance at this period
is very weak, and this reveals a problem of palaeoclimatology that
remains unsolved. (reprinted from (11) with permission from
aaaS.)
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Nicholas John Shackleton 445
the k–ar method, recognition of these in cores provided a quick
age scale. after revision of the 40k decay constants, the age of
the Matuyama–Brunhes reversal boundary (MBB) was revised to 730 ka.
a SPecMaP orbitally tuned chronology of imbrie and colleagues (29)
agreed with that age, but later SPecMaP work recognized
sufficiently high-quality records only to 300 ka ago (35). the 730
ka age was adopted by ruddiman et al. (1986), who retuned the
underlying section to obliquity with the same result (but fixed to
k–ar dated reversals lower in the section).
it is a matter of interest as to why the nearly correct
astronomical re-dating of MBB by Johnson (1982) giving an age of
790 ka was not widely adopted. Johnson’s method was sim-ply to
match extreme minima in benthic δ18o of the Shackleton & opdyke
records (5, 14) to the astronomical time scale at points of low
summer insolation during times of low orbital eccentricity. the
reason perhaps lay in the fact that those involved in the tuning
enterprise had evolved a more rigorous approach involving careful
assessment of stratigraphic complete-ness, requirement of an
adequate sedimentation rate to give the necessary resolution,
spectral methods and bandpass filtering of characteristic
frequencies of orbital components and precise orbital calculations.
Johnson lacked most of these except the latter, which he got from
Berger (1978). in addition, Johnson was an outsider to the
priesthood that evolved from the cliMaP project that did this work
(Shackleton, imbrie, Pisias, Berger, hays, Moore, Martinson, Prell,
ruddiman and others).
oDP Site 677 was a re-coring of Site 504B with overlapping cores
to produce a complete sequence of sufficient resolution through the
MBB (40). this was used by Shackleton and his colleagues (41) to do
a rigorous tuning of the section from 330 to 800 ka. they obtained
an age for the MBB of 780 ka, a value very close to the modern
accepted value of 778 ka (izett & obradovich 1994) (52).
Subsequently Bassinot and colleagues (46) deduced an age of 775
ka.
this presented a clear problem for radiometric dating, and
Shackleton and his colleagues (41) suggested that maybe the
geochronologists should look to their decay constants. the problem,
however, was partly more mechanical, residing in argon retention
and loss. this was solved by development of the 40ar/39ar method
that requires only ratios of argon isotopes, rather than absolute
amounts, for the calculation of an age. these methods gave the
‘correct’ answer, 778 ka (izett & obradovich 1994). the orbital
tuning led the way and set the scene for further refinements.
Notably, the Fish canyon tuff, used as a standard in the geological
time scale (Gradstein et al. 2004), with an ar–ar age of 28.02 Ma,
was orbitally dated to 28.201 ± 0.046 Ma ago (kuiper et al. 2004).
this was achieved via the 40ar/39ar dating of the already
astronomically dated Melilla tephras, which can be converted to an
astronomically calibrated age for Fish canyon sanidine (Fcs) by
treating the Melilla sanidines as astronomi-cally dated standards
and Fcs as the unknown (kuiper et al. 2004, 2008). although the
decay constant has been revised from (5.543 ± 0.020) × 10−10 per
year to (5.463 ± 0.214) × 10−10 per year (Min et al. 2000), the
astronomically calibrated age of the tuff is now the primary
stand-ard. resulting from this, the cretaceous/tertiary boundary
has been re-dated to 65.95 Ma ago (kuiper et al. 2008). thus the
‘confrontation’ produced by Shackleton’s careful tuning at the MBB
has spread like wildfire through dating of the cenozoic and is set
to continue through the Mesozoic as well.
Implications for planetary dynamicsorbital tuning requires a
source of high-quality calculations of insolation. Shackleton’s
col-laborations, first with andré Berger from the institute of
astronomy in louvain and latterly
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446 Biographical Memoirs
with the astronomer Jacques laskar at the Bureau des longitudes
in Paris, fulfilled that need. the success of the orbital tuning
approach led to some contributions in the opposite direction
because the geological record has very long ‘observation’ times
relative to those of astronomy. two papers (58, 65) with his
student heiko Pälike and laskar stand out.
on the basis of interference patterns between the precession and
obliquity components of geological data and astronomical solutions,
they extracted small changes in the precession constant p due to
tidal dissipation over the past 25 million years and constrained
the param-eters for tidal dissipation and the dynamical ellipticity
of the earth (58). these parameters were shown to have remained
close to the present-day values over that time. this most helpful
result indicated that, by using present-day values for dynamical
ellipticity and tidal dissipation in calculating insolation by la93
(laskar et al. 1993), large errors are not introduced during
astronomical tuning.
a second study (65) examined the chaotic behaviour of solutions
to calculations of earth’s orbit. Because the Solar System is
chaotic, the duration over which earth’s orbital variations can be
computed with confidence is limited. one of the main identified
mani-festations of chaos is the transition in the ratio of two
resonant astronomical frequencies, evidence of which can
potentially be detected in the rock record. Geological data
differenti-ate between astronomical solutions that exhibit a
transition since 40 Ma ago and those that do not. the chaotic
diffusion of the Solar System in the past can thereby be
constrained, a significant result for astronomical models. a
corollary of this work was support for the new astronomical model
of laskar et al. (2004) and the revised, younger age of the
oligocene–Miocene (o–M) boundary of about 23 Ma (64). this negated
the age of 24.0 Ma obtained from the cape roberts Project crP-2a
core via 40ar/39ar data for ages of polarity chrons in the vicinity
of the o–M boundary (Wilson et al. 2002), another confrontation won
by tuning. More recent work by laskar has improved astronomical
solutions of Solar System orbits further, and has now shown that
the long-term (405 000-year) variation of earth’s eccentricity is
very stable, and will allow the astronomical calibration of the
geological time scale to venture into the early cenozoic and
beyond.
δ13c, co2 and deep cIrculatIon
Shackleton pioneered the use and interpretation of carbon
isotopes in palaeoclimate studies, an undertaking in which he moved
on from studying the orbital forcing of glacial cycles to the
positive feedbacks that amplify this forcing into dramatic changes
in climate. oxygen isotope determinations are made via the
conversion of microfossil carbonate into co2 gas, and the method
also generates carbon isotope data, which previously were recorded
but not examined. recognizing that the carbon isotopic composition
of the oceans is affected by the amount of carbon stored on land,
in a famous paper in 1977 Shackleton used carbon isotopes to assess
the changing land reservoir of carbon between glacial and
interglacial times (15).
he also pioneered the use of carbon isotopes in palaeoclimate
studies. here he applied the carbon isotope method to test an idea
suggested by Wally Broecker of lamont–Doherty observatory to
explain changes in the co2 content of the atmosphere between ice
ages and today. the first reports had appeared, from work on air
trapped as bubbles in ice cores, that co2 concentrations at glacial
times were about 190 parts per million compared to 280 parts per
million in pre-industrial times. Broecker argued that the only way
that this
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Nicholas John Shackleton 447
could have occurred was by the transfer of carbon to the deep
ocean by increased biologi-cal productivity.
Because this process would preferentially enrich the lighter 12c
isotope in organic matter sinking to the sea floor, it should
produce larger differences in the ratio of 13c to 12c between
surface and deep seawater at glacial times as recorded in the
foraminifera shells. Shackleton’s record, published in 1983 in
Nature (25), predicted how atmospheric co2 has changed over the
past 100 000 years; this result was found to be very similar to
that obtained from bubbles in the antarctic Vostok ice core.
in 1980 Shackleton’s colleague Jean-claude Duplessy had shown
variation in the source and strength (its origin and transport) of
North atlantic Deep Water (NaDW) by means of oxygen isotopes
(Duplessy et al. 1980), and in 1983 Shackleton and his colleagues
(26) used carbon isotopes to the same end, demonstrating a large
gradient between North atlantic and eastern Pacific. oxygen isotope
records were found to be very similar, unlike those for carbon
isotopes. the atlantic–Pacific carbon isotope gradient showed that
the production of NaDW varied during the late Pleistocene, and that
the pattern of variation was not simply related to the oxygen
isotope record. oxygen isotope records of inter-oceanic gradients
supported the hypothesis that in the glacial the North atlantic was
colder, and less oxygenated, than it is today. Shackleton also
noted that his 1977 interpretation, in which the carbon isotope
record from the atlantic reflects changes in the terrestrial
biomass, was an oversimplifica-tion: ageing of deep water with
supply of light carbon from decaying phytoplankton was seen to be
important as well. this insight was followed up in several papers
with Duplessy (27, 28, 33, 36, 37).
Finally, these threads came together in 1988 with the first
successful determination of the radiocarbon age of Pacific deep
water, at the far end of what Broecker called the ‘conveyor’, where
Shackleton and his French colleagues (who had an accelerator
necessary for making 14c age determinations on the relatively rare
benthic foraminifera) showed that the glacial age was about 500
years more than modern (38). land-to-ocean carbon transfer plus the
more sluggish deep circulation had allowed a build-up of higher
nutrient concentrations in deep water, making it more corrosive to
carbonate sediments.
suB-orBItal changes
although Shackleton was the major figure in spectral analysis of
the records and determina-tion of changes on Milankovitch time
scales, workers on Greenland ice cores had shown in the 1980s (and
confirmed in the 1990s) much sharper changes at higher frequencies
(periods of 1–10 ka) that were not strongly periodic (Johnsen et
al. 1992; Dansgaard et al. 1993) and were thus unlikely to be
astronomically driven. Bond and colleagues (Bond et al. 1993; Bond
& lotti 1995) demonstrated that these were matched by changes
in sea surface temperature and ice discharge in the central North
atlantic. these so-called Dansgaard–oeschger (D–o) cycles had
abrupt warmings occupying a few decades and slower coolings,
periodically culminating in a ‘heinrich event’, a collapse of the
ice sheet with massive iceberg discharge.
We would not say that this work passed Shackleton by, but his
involvement in the investiga-tion of fine-scale changes was mainly
through his students Mark chapman and Mark Maslin (North atlantic)
and isabel cacho (western Mediterranean) (49, 59, 60). there was,
however, one study by him that has proved hugely influential (63).
the French development of a long
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piston corer deployed from the vessel Marion Dufresne allowed
the collection of cores with a high sedimentation rate, giving high
resolution. one of these from the Portuguese margin (core
MD95-2042) revealed key insights (63). oxygen isotope measurements
on glacial-age (isotope Stage 3) planktonic foraminifera
(Globigerinoides bulloides) were seen to resemble closely the
pattern of temperature change in Greenland (GRIP) (from the δ18o
ratio in ice), whereas those in the infaunal benthic foraminifera
(Globobulimina affinis) were very like the antarctic temperature
record (ice deuterium-to-hydrogen (D/h) ratio) in the Vostok ice
core (see figure 5). in the planktonic record the same sharp
increases in temperature as those in GriP suggested a secure basis
for correlation and transfer of the GriP age scale to the marine
core. The benthic δ18o record provides evidence of change in
continental ice volume and cor-relates well with the Vostok
temperature record. Vostok and GriP are synchronized through their
methane content, so the north–south age relation seen in the one
core is robust (figure 5). the sea bed at the core’s depth of 3146
m off Portugal in the Glacial was bathed in northward-flowing water
of circum-antarctic origin; hence the correlation.
Shackleton’s close connection with the ice-core community was
also evident in his use of the result of the MD95-2042 paper to
devise a new age scale for the cyclic D–o Stage 3 section of the
GriP ice core (66). this involved new 14c dates, correlation to
U-series dated cave speleothems and corals and correlation to
Greenland and antarctic ice cores. the authors concluded:
By utilizing the geologist’s approach of precise stratigraphic
correlation, it is possible to modify glaciological age models for
ice cores collected from Greenland and antarctica in such a manner
that they are mutually consistent to within a very few hundred
years.
Figure 5. Benthic and planktonic δ18O in Stage 3 in core
MD95-2042 with δ18o from Greenland (GriP) and D/h from antarctic
(Vostok) ice cores. Numbering of GriP interstadials is indicated;
crosses identify the age control points correlating the marine core
to GriP. (reprinted from (63) by permission of american Geophysical
Union. copyright © 2011 american Geophysical Union.)
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Nicholas John Shackleton 449
this exercise exemplifies a very important aspect of
Shackleton’s approach: stratigraphy and precise chronology. In this
case the payoff was a record of the Δ14c values associated with the
laschamp event, a brief collapse of the earth’s magnetic field that
caused increased 14c production.
shackleton and the terrestrIal quaternary
Being based in an institute founded on palaeobotany,
Shackleton’s earliest work related marine records to terrestrial
records. ever since emiliani’s studies (emiliani 1955a, 1966) the
question had arisen as to how the classic four glacials of the alps
and North america could fit with his sequence, which pointed to
many more than four cycles. in his second paper on the Quaternary
(3), Nick and charles turner (a palaeobotanist) argued that
emiliani’s marine sequence of glacials/interglacials was more
likely to be correct than that given by the marine
micropalaeontological interpretations of the time. Shackleton and
turner gave strong support to emiliani and made some pointed
remarks that indicated the turmoil in the Quaternary com-munity
caused by his results: ‘the fact that the record obtained by
emiliani is more complex than the classical picture of the timing
of the ice ages cannot any longer be taken to imply that it is
wrong’; ‘it is not sufficient to identify the largest events with
the best known names and leave it at that …’; and finally, ‘…
although Glass et al. (1967) have obtained a complete and
reproducible sequence … the micropalaeontological record which they
have obtained bears little relation to the chronology of glacial
events in europe.’
it did not take long for the world to come around to the
Shackleton–emiliani view; after all the evidence for many more than
four changes in ice volume was indeed strong. the problem remained
as to how to slot in the warm and cold periods inferred from pollen
in land sections that were often separated by hiatuses, many of
which were undetected. one promising approach was to find pollen in
marine strata in which an isotope stratigraphy could be determined.
From early in his career Shackleton had been associated with
lamont–Doherty Geological observatory in New York. also an
associate there in the 1970s was linda heusser, then of New York
University, a pollen specialist. together they showed in a marine
core an excellent record of glacial–inter-glacial vegetation
changes in the US Pacific Northwest tied to an isotope stratigraphy
(20). although this set the standard for future work, particularly
off Portugal by Shackleton’s student katy roucoux and associate
chronis tzedakis, it did not finally fix the general problem of
marine–terrestrial correlation, which still remains outstanding.
this is because fragmentary pol-len records can show whether
deposits record warm or cold conditions, but, given that ten cold
periods occurred in the past million years, which one is the dated
marine sequence?
a new approach to the problem uses the increasingly long and
complete lake sequences in europe, work with which Nick was closely
involved (55). a time scale for the four long-est pollen sequences
in europe was developed by tuning the terrestrial records to the
marine isotopic stratigraphy (the SPecMaP stack (35)) using
glacial–interglacial transitions as the tie points. Differences and
similarities of individual temperate stages were analysed by using
the combined records of several taxa representing the forest
succession from all sites. a complete stratigraphy of major
vegetation events for the last 430 ka now gives a potential system
for terrestrial biostratigraphical correlation with age
control.
another way of doing the correlation is the direct dating of
terrestrial deposits. this led Shackleton into the world of loess,
deposits of wind-blown dust. indeed, one of his earliest papers
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(4) puts data showing greater glacial trade wind vigour together
with an 800 ka-long planktonic δ18o record. a first attempt at
direct dating of loess by thermoluminescence was remarkably
suc-cessful, with an age for a last interglacial soil of 115 ± 10
ka (compared with 126–118 ka from marine stratigraphy) (32). Next a
direct comparison was made between the magnetic suscepti-bility
stratigraphy of chinese loess and dust accumulation rate in a
Pacific core with an isotope record dated to 500 ka ago (39). Soils
in loess correspond to warmer, wetter conditions, slower deposition
on land and at sea, and higher magnetic susceptibility in the
iron-rich soils. thus the dated marine climate record was
transferred to terrestrial deposits with far-reaching consequences,
especially in china. li Ping Zhou came to Nick’s laboratory to work
on loess stratigraphy, lumi-nescence dating and
magnetostratigraphy. the latter area yielded key insights into
pitfalls in applying magnetic reversal stratigraphy in terrestrial
loess sections. the problem was that the last
Figure 6. Nick in his office at the Godwin laboratory in Free
School lane. he is exactly as he would greet a visi-tor sitting at
a narrow bench next to the single window (looking out onto a brick
wall), picking foraminifera. (Photograph taken by Neville taylor of
cambridge University, Photographic and illustration Services.)
(online version in colour.)
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Nicholas John Shackleton 451
full magnetic field reversal, the MB boundary 778 ka ago, occurs
in a warm marine isotope stage (no. 19), but in cold climate loess
(rather than in the overlying warm soil where it ‘should’ be). the
source of the problem is the lock-in depth of the magnetic
signature, which was shown to be several metres down from the
contemporary land surface, and up to 10 ka too old (57).
shackleton’s IMpact on MarIne MIcropalaeontology and
palaeoMag-netIc work
Because Shackleton’s work was centred on the isotopic analysis
of carbonate shells of micro-fossils, especially foraminifera, he
became highly proficient in this area. he was adept at recognizing
species and picked most of the samples that he analysed, a most
effective form of quality control (figure 6). he also interacted
with a host of micropalaeontologists and had sev-eral PhD students
who worked on foraminifera and nannoplankton (coccoliths and
discoast-ers). in his palaeontological work three areas stand out:
synchroneity/diachrony of speciation and extinction datum levels,
orbital forcing and productivity changes, and foraminiferal
habi-tats. Most of Shackleton’s work in these areas was either
through his students or through his provision of isotope
stratigraphy to areas of interest to his palaeontological
colleagues.
correlation by fossils holds a key position in correlation
between cores and age determi-nation. an often unresolved question
(in all biostratigraphy) is whether the appearance or disappearance
from a stratigraphic section is globally or regionally synchronous.
Shackleton’s isotope stratigraphy and tuned ages allowed these
questions to be addressed. Several papers established the global
synchroneity of microfossil datums in coccoliths, diatoms,
radiolarians, and planktonic and benthic foraminifera; and in one
case a diachronous extinction was dem-onstrated (12, 17–19, 21, 23,
24, 45, 53, 61). More important than specific contributions is his
general approach, which, with modern cyclostratigraphy
(stratigraphy related to Milankovitch cyclicity), many are now
following. accurate age models permitted an inference of
accumu-lation rates and an approach to palaeoproductivity that was
then related to varying insolation and related environmental
variables. the isotopic ratios in foraminifera are partly
determined by the depth (temperature) at which they lived, a
feature that coxall and colleagues (61), for example, used to
reveal changes in the mode of life in a single evolutionary
lineage.
Shackleton relied on colleagues expert in palaeomagnetic
measurements from early in his career, because he recognized the
power of magnetic reversal stratigraphy for global correla-tion.
together with biostratigraphy it was the most natural accompaniment
to isotopic work. among his most important early papers were those
with the palaeomagnetist Neil opdyke (5, 14, 16). a later
development was estimation of the past intensity of the earth’s
magnetic field, an area in which he was again in the vanguard with
French palaeomagnetists laure Meynadier and Jean-Pierre Valet in
producing well-dated histories of intensity (44, 51). the intensity
is of value in both correlation and dating of cores and in
understanding the variation of cosmogenically produced isotopes,
especially 14c and 10Be.
a change of MInd?
Bill ruddiman has pointed out several aspects of Nick’s
scientific style and modus operandi. once having chosen a new
problem to explore, he forged well-chosen alliances to figure
out
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which sediment core was best for his purposes. invariably he
made the optimal decision and wrote the definitive paper. he also
liked to take strong positions in his talks, often proposing that a
particular factor was primary in a causal sense and that others
could be ignored. over the years, his designations of which factors
were ‘primary’ versus ‘secondary’ sometimes varied, because he
preferred stimulating debate more than holding to a strict
consistency.
a good example of this is his paper, ‘the hundred thousand-year
ice age cycle identified and found to lag temperature, carbon
dioxide and orbital eccentricity’, published in Science in 2000
(62): it is unusual in showing no new data but is one of
Shackleton’s most interesting and daring contributions. having
shown early in his career that the ice-volume component of the
marine oxygen isotope records is dominant over temperature, there
had been no way of knowing precisely what the contributions
are.
By comparing ice-core and deep-sea records in a complex manner,
he was able to separate the two contributions and showed that the
ice-volume component lags behind (it responds with a delay) the
changes in co2. in other words, changes in the ice sheets do not
cause changes in atmospheric co2. Shackleton’s analysis showed the
reverse: co2 had a major role in causing the changes from glacial
to interglacial conditions. this is an extremely profound analysis
with potentially very important ramifications for our future
climate. this paper also provided an interesting glimpse into the
way in which Shackleton addressed problems, described by tom
crowley in his obituary in Eos, Transactions, American Geophysical
Union as being characterized by a penetrating level of analysis and
an almost legalistic precision of phrasing.
shackleton and ocean drIllIng
the wellspring of much of Shackleton’s career lay in data
obtained from oceanic core sam-ples. Standard piston cores
available in the late 1960s were rarely longer than 20 m, and most
extended back in time no more than several hundred thousand years,
unless the sedimentation rate was very slow. the advent of deep
ocean drilling, which started in earnest in 1968, pro-vided a far
longer time window, one that he exploited with striking effect.
Nick Shackleton was a prolific contributor to the Deep Sea Drilling
Project (DSDP) and to its successor, the ocean Drilling Program.
From 1972 to 1998 he contributed 53 papers and data reports to the
volumes of those programmes, more than anyone other than the
projects’ staff. he sailed on four two-month drilling voyages on DV
Glomar Challenger and DV JOIDES Resolution (figure 7) in the North
and South atlantic and Pacific (legs 74, 138, 154 (chief scientist)
and 171B). he served as a member of both projects’ ocean history
Panels between 1975 and 1991 (chairman 1989–91). he was primus
inter pares of those responsible for providing one of the three
major pillars, that of ocean environmental history, on which the
international drilling programmes rest (the others being tectonics
and crustal petrology). his efforts over the years gave a
significant measure of the justification that the Uk Natural
environment research council needed to pay the Uk subscription to
join and remain a member of the drilling consortium.
Many of Shackleton’s seminal ideas were developed with
collaborators in the drilling pro-grammes, and often they first saw
the light of day in their initial reports and results volumes. For
example, the Shackleton and kennett work in Nature (13) on the
development of antarctic glaciation was presaged by their papers
the year before in volume 24 of the DSDP (8, 9); and similarly with
North atlantic climate and glaciation in Nature (31) and DSDP
volume 81 in
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Nicholas John Shackleton 453
1984 (30). his work on the development of orbitally tuned time
scales was also premiered in these volumes: that for the late
Neogene in 1995 (50) and for the oligocene in 1997 (54), along with
or ahead of their appearance in the mainstream literature (48,
56).
the working environment on a ship acts as a sort of incubator
with close contact between colleagues for months on end. in this
environment they developed the methods of multiple overlapping
coring to construct the complete sequences needed for the reliable
spectral analy-sis and orbital tuning of long records (42, 43, 47).
the staff of a drilling leg includes special-ists in all fields
relevant to palaeoceanography. From the samples obtained,
collaborations
(a)
(b)
Figure 7. (a) the original drilling ship, rV Glomar Challenger,
1968–89. (b) the successor ship, rV JOIDES Resolution, after refit
in 2003. (credit: ioDP/taMU.) (online version in colour.)
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established and projects initiated flowed work on isotope
history from the Pleistocene down to the oligocene (0–30 Ma ago),
isotope studies in squeezed pore waters, fossil abundance
variations and responses of biota to orbital forcing, isotope
variations and planktonic foramini-fer depth habitats, chemical
composition of sediments and productivity variations, sediment
fluxes based on orbitally tuned time scales, and determinations of
relative geomagnetic inten-sity—a small selection from a huge
output. all this was underpinned by meticulous attention to
stratigraphic correlation and the establishment of precise
chronology. his contribution to virtually all aspects of Quaternary
research was recognized by his being elected President of iNQUa
(the international Union for Quaternary research) from 1999 to
2003.
the godwIn laBoratory, MusIc and the postage staMp
The Godwin Laboratorythe Godwin laboratory on Free School lane
was a Mecca for visitors both from earth Sciences across Downing
Street and from outside cambridge. he was supportive of and
Figure 8. annual Godwin laboratory photograph from 2003–04. Nick
Shackleton is fourth from the left in the front row. the authors
are fourth from the left in the second row from the front (i.
N.Mcc.) and sixth from the left in the front row (h. e.). the full
list is (from left to right): front row, Patrizia Ferretti, Pallavi
Jha, Maryline Vautravers, Nick Shackleton, tjeerd van andel, harry
elderfield, linda Booth, Jimin Yu; second row, lucia de abreu,
isabel cacho, Mike hall, Nick Mccave, caroline Daunt, Mervyn
Greaves, James Partington; third row, thorsten keifer, James rolfe,
katcha rinne, helen houghton; back row, Simon crowhurst, John
Waterhouse, roy Switsur, Steve Barker, luke Skinner. absent were
aradhna tripati, Fiona hall, christina De la rocha and chronis
tzedakis. (online version in colour.)
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Nicholas John Shackleton 455
helpful to younger scientists worldwide, and gave freely of his
time to discuss their results. in his trademark sandals, he was
unfailingly polite and helpful with the many who sought him out,
and his cambridge laboratory became something of a pilgrimage site.
he let his stu-dents and an entire community share in his
brilliance and vision. andy Gale, in his Guardian obituary, said
that to know that Nick Shackleton liked your work and supported
your efforts provided a much-needed boost to the self-confidence of
researchers. Shackleton’s labora-tory became a factory for
stable-isotope analyses with a huge annual output that could not be
beaten by other laboratories. this was to a large degree due to
Mike hall, his laboratory manager. each year a Godwin laboratory
photograph was taken (figure 8 is an example), the participation
being in part a movable feast, including visitors who happened to
be present and students and postdoctoral workers of i. N.Mcc. and
h. e. on one occasion, Nick (Shackleton) was absent, so a space was
left for him and he stood on the spot on his return and was
inserted into the photograph electronically.
Musicas well as his many scientific accomplishments, Shackleton
excelled in another area, that of music, which was almost as
important to him as science. he was a very accomplished clarinet
player and an internationally renowned collector and scholar of the
instrument. in cambridge he lectured and supervised in the Faculty
of Music on the physics and acoustics of music. Shackleton
contributed articles to both editions of The new Grove dictionary
of music and musicians (1980 and 2001) as well as to The Cambridge
companion to the clarinet (ed. colin lawson) and journals such as
Galpin Society Journal. he also reviewed books on musical
instruments, and contributed notes for lP and cD recordings.
Shackleton amassed what is almost certainly the largest
collection of clarinets in the world. When he bequeathed it to the
University of edinburgh his collection numbered over 800
instruments, including 817 clarinets and basset horns. he liked to
remark, somewhat disin-genuously (having had no children), that all
this could be done on just a university lecturer’s salary.
Quaternary research was the major interest in his life; music
was a very close second. in his words: ‘Both music and science are
for me intensely human activities, and both have found me
innumerable friends.’ Shackleton’s love of music was known to his
science colleagues, especially through his participation in the
‘palaeomusicology’ concerts that were one of the highlights of the
international Paleoceanography conferences.
an appreciation of Nick as a musician is given here by ingrid
elizabeth Pearson, Nick’s partner at the time of his death, and
herself a scholar and clarinettist:
only when Nick (Nikki, as he was known by those closest to him)
Shackleton was knighted in 1998, did his musician acquaintances
realise just how distinguished a scientist he was! those from
outside the Uk got to know Nick through his comprehensive article
on the clarinet in The new Grove dictionary of music and musicians,
published under the editorship of the late Stanley Sadie, in 1980.
as an undergraduate at the University of Sydney in the early 1990s,
i received a personal letter from Nick answering a question about
an aspect of clarinet history. i was so excited i ran the length of
the campus to show the letter to my lecturers! Subsequent
correspondence included an invitation to stay with Nick, and
Vivien, during my first visit to the Uk in late 1992. thanks partly
to Nick’s generos-ity in sharing both his collection and vast array
of supporting documentary materials as well as his very real
interest in my curiosity about an aspect of the clarinet’s history,
i returned to the Uk a few years later to undertake doctoral study
in that area. i was just one of many younger people fortunate
enough to have been nurtured by Nick, in either his musical or his
scientific life.
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this nurturing was to have a particularly profound and timely
effect on the historical perform-ance movement, through Nick’s
friendship with the brilliant young cambridge woodwind-instru-ment
maker Daniel Bangham. Nick and Daniel first met in 1979, and by the
early 1980s Daniel’s workshop was making superb copies of many of
Nick’s instruments. other makers soon followed suit, including
those from France, canada, the Netherlands and the USa. these
instruments can be heard on recordings and are still in use among
players today. Nick was also happy to loan instruments from his
collection, in playing condition, for concerts and recordings. and
many of the Shackleton instruments were loaned to other museums,
most recently to the Berlin Musical instrument Museum for the
2004/5 exhibition celebrating 300 years of the clarinet.
evidence of Nick’s standing in the musical community was the
number of professional musi-cians he counted among his personal
friends. they were regular visitors to his home in tenison avenue,
cambridge, not only to marvel at the treasures contained in the
clarinet room (figure 9), but to engage in musical, intellectual
and social banter. Nick knew most of the clarinettists in
orchestras across the world. if he didn’t, he’d take the
opportunity to meet them after the concert, if possible.
Figure 9. ‘Nikki’ in his clarinet room. (Photograph taken by
ingrid Pearson; reproduced with permission.) (online version in
colour.)
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Nicholas John Shackleton 457
Nick was an avid concert-goer, with wide-ranging and eclectic
musical taste. this was also reflected in his personal collection
of 78s, lPs and cDs, which included music from ethiopia, Georgia
and india alongside the staples of Western art music, particularly
works for wind instru-ments. Music by Leoš Janáček, Richard Strauss
and Igor Stravinsky were his favourites. Nick is, in fact, one of
the basset horn players on The Music Party’s recording of Mozart’s
Serenade in B♭, k361/370a, the so-called ‘13-instrument Serenade’,
an early period-instrument documentation of the work. in this
recording he plays on an instrument by raymund Griesbacher from his
collec-tion. he also appears in a recording of music by Georg
Druschetzky, performing on a clarinet by kaspar tauber from his
collection.
Nick approached music with the insight, determination and
diligence that marked his sci-entific work. he had practised his
clarinets regularly since the days as bass clarinettist in the
orchestra of the cambridge University Music Society, and earlier in
the army. latterly, Nick enjoyed playing chamber music with his
cambridge friends most weeks. in the words of Nick’s friend, the
late William Waterhouse, the eminent bassoonist and scholar, ‘in
Nick, musicians had, for the first time, the benefit of a brilliant
researcher applying the rigour of a scientist to our problems’.
The stampWhy the stamp? in 2010 the royal Society celebrated 350
years of science since its foundation in 1660 by the royal Mail’s
issuing a set of ten stamps of notable members of the Fellowship.
one of the ten was of Nick Shackleton (figure 10). the others were
charles Babbage, robert Boyle, Benjamin Franklin, Dorothy hodgkin,
edward Jenner, Joseph lister, isaac Newton, ernest rutherford and
alfred russell Wallace: a talented group!
Nick Shackleton died of leukaemia at a relatively young age. he
was first diagnosed with non-hodgkin’s lymphoma in 2001.
tragically, an element of the chemotherapy manifested itself in
late 2005 as a leukaemic complication, and it was this that led to
Shackleton’s untimely death. he had been retired for about one
year. he explained to many who said they expected he would carry on
as usual after retirement that, to the contrary, he would have more
time for his music. his retirement coincided with the physical move
of the Godwin laboratory to space within the main site of the earth
Sciences Department. his mass spec-trometers were moved across
Downing Street (and still work well) and a ‘bolt hole’ office for
him was included in the plans for the newly located Godwin
laboratory. Sadly, he occu-pied it only for a short time.
Figure 10. the first-class Uk postage stamp. (copyright © 2010
royal Mail Group ltd)(online version in colour.)
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458 Biographical Memoirs
awards and honours
1985 Fellow of the royal Society Shepard Medal for Marine
Geology, Society for Sedimentary Geology, USa carus Medal, Deutsche
akademie für Naturforscher ‘leopoldina’1987 lyell Medal, Geological
Society of london1988 Founding Member, academia europaea1990
Fellow, american Geophysical Union huntsman Medal for Marine
Sciences, Bedford institute of oceanography, canada1995 crafoord
Prize, royal Swedish academy of Sciences1996 honorary Doctor of
laws, Dalhousie University, canada Wollaston Medal, Geological
Society of london1997 honorary Doctor of Philosophy, Stockholm
University, Sweden1998 knighthood, for services to the earth
Sciences1999 Milankovitch Medal, european Geophysical Society2000
Foreign associate, US National academy of Sciences2001 Foreign
Member, royal Netherlands Society of arts and Sciences2002 honorary
Doctorate, Geology, University of Padua, italy ewing Medal,
american Geophysical Union2003 honorary Member, european Union of
Geosciences Urey Medal, european association of Geochemistry royal
Medal, royal Society2004 Vetlesen Prize, columbia University2005
Founders Medal, royal Geographical Society Blue Planet Prize, asahi
Glass Foundation, Japan
acknowledgeMents
obituaries of Nick Shackleton appeared anonymously in The Times,
by tom crowley in Eos, Transactions, American Geophysical Union, by
andy Gale in The Guardian, by Gerald haug and larry Peterson in
Nature, by harry elderfield in The Independent, by Nadine Brozin in
The New York Times, by Jim hayes in Quaternary Science Reviews, by
Bill ruddiman in Science and by Nick Mccave in Oxford dictionary of
national biography. We have quoted directly or indirectly from
their words, and this has helped us in writing this account. We
also thank heiko Pälike for his comments on sections of the
manuscript.
the frontispiece photograph was taken in 2004 by the Godwin
laboratory, cambridge, Uk, and is reproduced with permission.
(online version in colour.)
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