The Deep Carbon Observatory: A Ten-Year Quest to Study Carbon in Earth

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The Deep Carbon Observatory: A Ten-Year Quest to Study
Carbon in Earth
Craig M. Schiffries, Andrea Johnson Mangum, Jennifer L. Mays, Michelle Hoon-Starr, Robert M. Hazen
Geophysical Laboratory, Carnegie Institution for Science, Washington, DC 20015, USA
1. Overview
The Deep Carbon Observatory (DCO) is a ten-year research pro-
gram to investigate the quantities, movements, forms, and origins
of carbon in Earth. More than 90% of Earth’s carbon may reside in
the planet’s deep interior, and DCO’s overarching mission is to
understand Earth’s entire carbon cycle—beyond the atmosphere,
oceans, and shallow crustal environments, which have drawn most
previous research attention—to include the deep carbon cycle [1,2].
A decade of focused research has led to major discoveries by DCO
scientists on the physical, chemical, and biological roles of carbon
in Earth.
To pursue its multidisciplinary mission, DCO connects more
than 1200 scientists worldwide, broadly grouping them into four
Science Communities: Extreme Physics and Chemistry, Reservoirs
and Fluxes, Deep Energy, and Deep Life (Table 1). The program also
emphasizes four crosscutting activities that bridge community
boundaries—namely, data science, instrumentation, field studies,
and modeling and visualization—and several cross-community
groups that provide essential services to the entire DCO commu-
nity (Fig. 1).
In addition to its scientific advances, DCO has created an endur-
ing legacy of interdisciplinary and international community build-
ing, successfully establishing a diverse, dynamic, and collaborative
community of geologists, physicists, chemists, and biologists in
more than 50 countries. In particular, DCO has focused on cultivat-
ing the next generation of deep carbon researchers by supporting
early career scientists who will carry on the tradition of explo-
ration and discovery for decades to come.
The vision, guiding questions, and scientific goals of DCO were
initially framed at an international Deep Carbon Cycle Symposium
at the Carnegie Institution for Science in 2008. This symposium led
to a successful proposal to the Alfred P. Sloan Foundation to estab-
lish a decadal research program on deep carbon science from 2009
to 2019. The Alfred P. Sloan Foundation pledged seed funding of 50
million USD over ten years to foster DCO. DCO has leveraged the
support from the Alfred P. Sloan Foundation with more than 500
million USD in support from other sources, including international
organizations, national science agencies, foundations, and the
private sector.
2. The Extreme Physics and Chemistry Community
DCO’s Extreme Physics and Chemistry Community is dedicated
to improving our understanding of the physical and chemical
behavior of carbon at extreme conditions, as found in the deep
interiors of Earth and other planets. This Community is making
transformational advances in our understanding of carbon in min-
erals, magmas and melts, and aqueous fluids at extreme condi-
tions. DCO scientists have published new results on the
properties of carbon-bearing minerals at high pressures and tem-
peratures, including the structure, compressibility, and elasticity
of carbonate minerals, carbides, carbon dioxide (CO
2
) ices, and
clathrates. One discovery is the formation of phases with sp
3
hybridization of carbon to yield tetrahedral coordination of carbon
by oxygen at elevated pressure and temperature. Under ambient
conditions, CO
2
is a linear molecule; however, at sufficiently high
pressure, CO
2
transforms into a polymerized framework structure
in which carbon is tetrahedrally coordinated with four oxygen
atoms [3]. Dense forms of polymeric CO
2
are potential reservoirs
of carbon in planetary interiors. The stabilization of tetrahedrally
coordinated carbon has profound implications if this carbon substi-
tutes for tetrahedrally coordinated silicon in silicate minerals. This
substitution mechanism has been verified experimentally [4], and
indicates a potential reservoir for carbon in Earth and planetary
interiors. DCO scientists have also conducted extensive research
on carbonate minerals under extreme conditions. Under ambient
conditions, carbon forms trigonal planar structural units in car-
bonate minerals. At high pressure, carbonate minerals transform
into denser structures in which carbon is tetrahedrally coordi-
nated with four oxygen atoms [5–11]—a discovery that has
important implications for the stability and properties of carbon-
ates in the deep carbon cycle [12,13]. Complementary experimen-
tal studies of carbon in iron at extreme conditions provide
conflicting evidence about the elusive role of carbon in Earth’s
core [14–16].
Magma ocean processes set the initial distribution of carbon
and conditions for further development of Earth’s deep carbon
cycle [17]. Magmas are also the main agent for transporting carbon
from Earth’s interior to its surface [18]. Conversely, carbon influ-
ences deep Earth dynamics by inducing melting and mobilization
https://doi.org/10.1016/j.eng.2019.03.004
2095-8099/Ó2019 THE AUTHORS. Published by Elsevier LTD on behalf of Chinese Academy of Engineering and Higher Education Press Limited Company.
This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Engineering 5 (2019) 372–378
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of structurally bound mineral water [19]. Melting may also have a
major impact on the recycling of subducted carbon into the deep
mantle. The melting-phase relations of recycled oceanic crust sug-
gest that slabs undergo melting and loss of carbonate components
in the transition zone, creating a barrier to deep carbon subduction
[20]. Recent experimental studies indicate that carbonatitic liquids
provide a potentially significant pathway for carbon recycling at
shallow depths beneath arcs [21].
DCO is making rapid advances in our understanding of the
role of aqueous fluids in the deep carbon cycle. Until recently,
thermodynamic models developed to understand water-rock
interactions in Earth’s upper and middle crust could not be
extended to deeper environments, largely because the dielectric
constant of water at extreme conditions was unknown. DCO sci-
entists removed this barrier by conducting first-principles calcu-
lations of the dielectric constant of water under extreme
conditions and the transport of carbonates in the deep Earth
[22]. These calculations were used in combination with experi-
mental results [23] to develop the Deep Earth Water (DEW)
model [24]. Initial results from the DEW model demonstrate that
organic carbon plays an important role in subduction zone fluids
[25] and that diamonds can form due to pH shifts in deep fluids
[26]. The role of carbon in setting the pH of subduction zone
fluids can now be assessed, with implications for volatile and
metal cycles [27]. This approach is transforming our view of
global geochemical transport [28].
3. The Reservoirs and Fluxes Community
DCO’s Reservoirs and Fluxes Community is dedicated to iden-
tifying the principal deep carbon reservoirs, determining the
mechanisms and rates by which carbon moves among
these reservoirs, and assessing the total carbon budget of Earth.
Table 1
DCO decadal goals.
DCO Science Community Decadal goals
Extreme Physics and
Chemistry
Seek and identify possible new carbon-bearing materials in Earth and planetary interiors
Characterize the structural and dynamical properties of materials and identify their reactions and transformations at conditions rele-
vant to Earth and planetary interiors
Develop, extend, combine, and exploit experimental tools to investigate carbon-bearing samples in new regimes of pressure, temper-
ature, and bulk composition
Develop, extend, and improve databases and simulations of deep carbon material properties, reactions, and transport for integration
with quantitative models of global carbon cycling
Reservoirs and Fluxes Establish open access, continuous information streams on volcanic gas emission and related activity
Determine the chemical forms and distribution of carbon in Earth’s deepest interior
Determine the seafloor carbon budget and global rates of carbon input into subduction zones
Estimate the net direction and magnitude of tectonic carbon fluxes from the mantle and crust to the atmosphere
Develop a robust overarching global carbon cycle model through deep time, including the earliest Earth and coevolution of the geo-
sphere and biosphere
Produce quantitative models of global carbon cycling at various scales, including the planetary scale (mantle convection), tectonic scale
(subduction zone, orogeny, rift, volcano), and reservoir scale (core, mantle, crust, hydrosphere)
Deep Energy Utilize field-based investigations of approximately 25 globally representative terrestrial and marine environments to determine pro-
cesses controlling the origin, form, quantities, and movements of abiotic gases and organic species in Earth’s crust and uppermost
mantle
Implement the use of DCO-sponsored instrumentation, especially revolutionary isotopologue measurements, to discriminate the abiotic
versus biotic origin of methane gas and organic species sampled from global terrestrial and marine field sites
Quantify as a function of temperature, pressure, fluid and solid compositions, and redox state the mechanisms and rates of fluid-rock
interactions that produce hydrogen (H
2
), abiotic forms of hydrocarbon gases, and more complex organic compounds
Integrate our quantitative understanding of the processes that control the origins, forms, quantities, and movements of abiotic vs. biotic
carbon compounds with quantitative models of global carbon cycling
Deep Life Determine the processes that define the diversity and distribution of deep life as it relates to the carbon cycle
Determine the environmental limits of deep life
Determine the interactions between deep life and carbon cycling on Earth
Fig. 1. DCO organizational structure.
C.M. Schiffries et al. / Engineering 5 (2019) 372–378 373

Its Diamonds and Mantle Geodynamics of Carbon (DMGC) group
has created an international infrastructure to study Earth’s deep
interior through the unique record preserved in diamonds. DMGC
aims to advance deep Earth exploration by studying natural
diamonds and diamond-forming fluids and melts in order to
elucidate carbon mobility in Earth through geologic time [29].
Because this effort hinges, in part, on sample availability and a
coordinated effort toward sample research, DMGC is developing
registered sample collections and a geochemical database of
diamonds and diamond inclusions.
The discovery of native metals, metal carbides, and reduced
volatiles in large gem-quality diamonds indicates that these dia-
monds formed from metallic liquid in Earth’s deep mantle, and
provides broad implications for Earth’s evolution [30]. In contrast,
highly saline fluids from a subducting slab are the source for cer-
tain fluid-rich fibrous diamonds; the data imply a strong associa-
tion between subduction, mantle metasomatism, and fluid-rich
diamond formation, as well as pointing to the important effect of
subduction-derived fluids on the composition of the deep litho-
spheric mantle [31]. The discovery of hydrous ringwoodite
included within an ultradeep diamond provides direct evidence
of a hydrous mantle transition zone, which may have a key role
in terrestrial magmatism and plate tectonics [32]. The discovery
of calcium silicate perovskite in a diamond that formed 780 km
below Earth’s surface provides the first direct observation of
Earth’s fourth most abundant mineral; the isotopic composition
of carbon in the surrounding diamond, together with the pristine
high-pressure CaSiO
3
structure, indicate the recycling of oceanic
crust into the lower mantle [33]. Blue boron-bearing diamonds
contain mineral inclusions indicating that these diamonds formed
in oceanic lithosphere that was subducted into Earth’s lower man-
tle. Blue diamonds indicate a pathway for the ultradeep recycling
of carbon, water, and other materials from the crust to the lower
mantle and back to the surface [34].
The Reservoirs and Fluxes Community’s Deep Earth Carbon
Degassing (DECADE) initiative aims to determine accurate global
fluxes of volcanic CO
2
to the atmosphere. To achieve this goal,
DECADE has launched an intensive field-based effort to install
CO
2
-monitoring networks on 20 of the world’s 150 most actively
degassing volcanoes. DECADE also conducts laboratory-based
studies, which focus on using gas samples and melt inclusions to
provide empirical constraints on carbon degassing to the
atmosphere.
High-frequency gas monitoring at Turrialba Volcano in Costa
Rica revealed CO
2
precursors to eruptions, which lays the foun-
dation for improved volcanic eruption forecasts [35]. An interna-
tional team led by DECADE members demonstrated that the
Ambrym basaltic volcano in the Vanuatu Arc in the southwest
Pacific Ocean ranks among the top-three known persistent emit-
ters of volcanic gas at the global scale [36]. There is growing evi-
dence that continental rifts represent a major source of deep
carbon released to Earth’s surface from both volcanoes and fault
zones [37–40]. New measurements of olivine-hosted melt inclu-
sions from the Mid-Atlantic Ridge indicate that upper mantle
carbon content varies by almost two orders of magnitude glob-
ally, which can affect the dynamics of melting, the style of vol-
canism, and the evolution of Earth’s atmosphere via planetary
outgassing [41]. For the first time in a global study, DCO scien-
tists found evidence for higher carbon output (m(CO
2
)/m(S
total
),
where m(CO
2
) and m(S
total
) are the amounts of CO
2
and total sul-
fur, respectively) in volcanic arcs where carbonate sediment sub-
ducts on the seafloor [42]. A synthesis of global carbon and
helium isotopic data from arc volcanoes concludes that the car-
bon isotope composition of mean global volcanic gas is consider-
ably heavier than the canonical mid-ocean ridge basalt value;
this result indicates that reworking of crustal limestone is an
important source of volcanic carbon, which has implications
regarding the return of carbon to the deep mantle and for
Earth’s past climate [43].
Modeling and visualization of Earth’s deep carbon cycle through
deep time contributes significantly to DCO’s overall goals. A reeval-
uation of carbon fluxes in subduction zones indicates that almost
all of the carbon in subducting sediments and oceanic plates may
be extracted in fluids and melts, with relatively little carbon being
returned to the convecting mantle [44]. Plate tectonic reconstruc-
tions establish connections between the deep carbon cycle and
the concentration of CO
2
in the atmosphere over geologic time
scales [45–47]. Numerical models of the role of volatiles in reactive
melt transport in the asthenosphere indicate that CO
2
and water,
despite their low concentration, have an important control on
the extent and style of magma genesis, as well as on the dynamics
of melt transport and the stranding of carbon at the lithosphere–
asthenosphere boundary; these findings have significant implica-
tions for deep Earth degassing [48,49].
4. The Deep Energy Community
DCO’s Deep Energy Community is dedicated to developing a
fundamental understanding of environments and processes that
regulate the volume and rates of the production of abiogenic
hydrocarbons and other organic species in the crust and mantle
through geological time. This research is transforming our under-
standing of methane (CH
4
) and includes novel information about
its origin, provenance, and formation temperature. Revolutionary
advances in instrumentation make it possible to discriminate
between methane produced by abiotic synthesis and that produced
by biological processes.
The Panorama mass spectrometer is the first instrument
capable of resolving the two doubly substituted mass-18
isotopologues of methane (‘‘clumped isotopes”)—
13
CH
3
D and
12
CD
2
H
2
—at natural abundances [50]. A paper by Edward Young
and 23 co-authors from 14 institutions in eight countries [51]
reports the first resolved measurements of two doubly substituted
isotopologues of methane in gases collected from diverse geologic
settings around the globe, including major natural gas fields, ultra-
mafic complexes, and ancient waters from deep underground
mines in Precambrian Cratons. If thermodynamic equilibrium is
achieved, then
D
13
CH
3
D and
D
12
CD
2
H
2
serve as two independent,
intramolecular thermometers. If thermodynamic equilibrium is
not achieved, then temperature cannot be determined by this
method; however, the data may provide the means for distinguish-
ing between abiotic and biotic origins of methane. Disequilibrium
isotopologue ratios can provide information about methane forma-
tion mechanisms and serve as tracers that provide insights into
mixing, diffusion, kinetics, and other processes [51].
Ubiquitous dissolved methane in hot-spring fluids emanating
from submarine hydrothermal vents is a potential carbon source
for microbial communities living at and below the seafloor and
in the water column. Methane clumped isotope analyses indicate
a hot (270–360 °C), deep, and abiotic origin for methane at seafloor
hot springs in unsedimented oceanic crust [52]. This important
finding was made possible by a novel tunable infrared laser direct
absorption spectroscopy instrument [53], which was developed
with DCO support. Using the same instrument, microbial methane
from a broad range of natural and cultured samples produced non-
equilibrium clumped isotope signals [54]. The clumped isotope
anomalies place new constraints on biogeochemical sources, sinks,
and budgets of methane.
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Computational studies have identified a novel mechanism for
abiotic methane formation: The effects of confinement on carbon
dioxide methanation in nanopore-controlled chemical reactions
can shift thermodynamic equilibrium toward methane production
[55]. This mechanism for producing abiotic methane may be appli-
cable to interactions between seawater and oceanic crust, and
could explain the origin of methane observed in some submarine
hydrothermal vent systems.
Experimental studies have been conducted on abiotic methane
formation under a wide range of conditions, including reducing
environments that develop during serpentinization of ultramafic
rocks. Using isotopically labeled CO
2
, some experiments have
shown that earlier claims of CH
4
production by serpentinization
at low temperatures were incorrect [56]. However, other experi-
ments have shown that CO
2
reduction in the presence of extant
hydrogen (H
2
) vapor leads to significant methane production at
low temperatures [56]. Similarly, the production of methane in ser-
pentinized ultramafic rocks can be catalyzed at low temperatures
by ruthenium (Ru)-bearing chromite minerals [51,57].
DCO researchers have studied the production of H
2
and CH
4
dur-
ing serpentinization at field sites around the world. For example,
International Ocean Discovery Program (IODP) Expedition 357:
Atlantis Massif Serpentinization and Life successfully cored a
transect across the Atlantis Massif on the flank of the Mid-Atlantic
Ridge. This expedition examined the role of serpentinization in
driving seafloor hydrothermal systems, sustaining microbial
communities, and sequestering carbon [58].
In a remarkable paper, DCO scientists documented abiotic syn-
thesis of amino acids in the oceanic lithosphere [59]. Amino acids
formed abiotically during a late alteration stage of massif serpen-
tinites beneath the Atlantis Massif. This discovery has significant
implications for the origins of life, ancient metabolisms, and the
functioning of the present-day deep biosphere.
Ancient groundwaters in Precambrian Cratons are now recog-
nized as important sources of H
2
, which is available to support
the subsurface biosphere to depths of several kilometers [60].
The contribution of Precambrian continental crust to global H
2
pro-
duction had been greatly underestimated. If H
2
production via both
radiolysis and hydration reactions is taken into account, H
2
pro-
duction rates from the Precambrian continental lithosphere are
comparable to estimates from marine systems [61]. Incorporating
H
2
production from the Precambrian continental lithosphere could
double existing estimates of global H
2
, increasing the habitable
volume of Earth’s crust.
Research on molecular hydrogen is not limited to Earth. DCO
scientists are members of the teams that discovered molecular
hydrogen and higher hydrocarbons escaping from Saturn’s moon
Enceladus, which has a layer of ice covering a subsurface ocean
[62,63]. The discovery of molecular hydrogen indicates that water
is reacting with rocks on the floor of the alien ocean [62]. The pro-
cess responsible for producing molecular hydrogen on Enceladus
might resemble hydrothermal vents on Earth’s seafloor. The dis-
covery of complex carbon compounds emanating from Enceladus
[63] suggests that the moon’s ocean may contain the raw ingredi-
ents necessary for life.
5. The Deep Life Community
DCO’s Deep Life Community is dedicated to assessing the nature
and extent of the deep microbial and viral biosphere. This Commu-
nity has expanded the known boundaries of Earth’s microbial and
viral biosphere, and investigated the interactions and processes
that govern how ecosystems survive and evolve. DCO has united
researchers approaching overarching deep life questions from
varying perspectives by: ①studying the subsurface biosphere in
the sediments and rocks of both the continents and the seafloor;
②exploring what genomes can reveal about the limits and possi-
ble origins of life; and ③investigating the response of deep life to a
range of physical and chemical extremes.
The lower boundary of the deep sedimentary biosphere was
explored by DCO researchers participating in IODP Expedition
337: Deep Coalbed Biosphere off Shimokita.They discovered a
microbial ecosystem producing methane from Miocene coalbeds
nearly 2.5 km below the seafloor [64]. The assemblages appear to
be the descendants of microbes buried in terrigenous sediments
up to 20 million years ago. Despite low cell numbers, these
microbes are actively growing at rates that range from months to
over 100 years—some of the slowest microbial biosynthesis rates
ever directly measured by incubation [65]. Other DCO researchers
found microbial communities exhibiting aerobic respiration in
sediments 75 m below the seafloor in the South Pacific Gyre, a
finding that suggests that oxygen and aerobic communities may
occur in sediments over 15%–44% of the Pacific and perhaps
9%–37% of the global seafloor [66].
The select survival of taxa capable of coping with the severe
energy stresses characteristic of subsurface environments may
cause these taxa to become the founders of more common commu-
nities such as Bathyarchaeota, which may play an important role in
carbon cycling [67]. Therefore, microbial communities existing at
extremes, such as the elevated temperatures in hydrogen-rich
hydrothermal vent systems on the Mid-Cayman Rise, are critical
to understanding the limits of deep life [68]. For example, mem-
bers of the Bathyarchaeota are among the most abundant, diverse,
and widely distributed Archaea in marine subsurface habitats glob-
ally. A metagenomic study has shown that Bathyarchaeotal sub-
groups employ versatile metabolisms, which in turn supply
substrates for heterotrophic and methanogenic community mem-
bers [69]. Another metagenomic study indicates that distinct evo-
lutionary pressures correlate with genes related to nutrient uptake,
biofilm formation, or viral invasion, a finding that is consistent
with distinct evolutionary histories between geochemically differ-
ent hydrothermal vent fields [70].
Based on observations of Archaea and bacteria at 77 worldwide
locations with different marine ecosystems, DCO researchers
determined that methane seep communities exhibit lower diver-
sity than communities in other ecosystems. The surviving assem-
blages reflect the most favorable microbial metabolisms at
methane seeps and distinguish the seep microbiome from other
seafloor microbiomes [71]. Although only a few species of methan-
otrophs occur at all seeps worldwide, these microorganisms seem
to greatly influence the methane budget of the ocean.
DCO also investigates the deep terrestrial continental bio-
sphere. Based on a compilation of cell concentration and microbial
diversity data from continental subsurface localities around the
globe, DCO researchers estimated that the continental subsurface
hosts (2–6) 10
29
cells, and found that bacteria are more abun-
dant than Archaea and that their community composition is corre-
lated to sample lithology [72].
Researchers investigating a subsurface lithoautotrophic micro-
bial ecosystem (SLiME) in the ancient Witwatersrand Basin found,
to their surprise, that sulfur-driven autotrophic denitrifiers were
the dominant microbial group. Further analysis revealed that
metabolic community cooperation enabled less typical metabolic
reactions to prevail and stabilize the ecosystem [73]. Modeling also
suggests that food—not dissolved oxygen—limits eukaryotic popu-
lation growth at 1.4 km depths in 12 300-year-old palaeometeoric
fissure water in South African mines [74,75]. Microbial
communities occurring in connection with hydraulic fracturing
during hydrocarbon resource development in the deep subsurface
also provide clues to the deep terrestrial biosphere [76]. Microbes
exist as deep as 2500 m below land surface and exhibit salt
C.M. Schiffries et al. / Engineering 5 (2019) 372–378 375

tolerance, metabolic capacity without electron acceptors, and evi-
dence of active viral infection.
Through the DCO Census of Deep Life (CoDL), DNA sequencing
has provided new and value-added information about carbon
cycling, deep biosphere evolution, and the connection between
ecosystems and environments both continental and marine. For
example, CoDL researchers used 16S DNA sequencing to identify
bacterial and archaeal taxa associated with eight minerals from a
sub-seafloor microbial observatory on the Juan de Fuca Ridge,
280 m below the seafloor. They confirmed that distinct communi-
ties colonize different minerals, and that these communities group
by mineral chemistry [77].
DCO’s Extreme Biophysics group has approached the challenges
of life existing in these extreme environments from a completely
different angle. By focusing on molecular-level adaptation to life
under extreme conditions, these researchers are advancing our
knowledge of the basic chemistry and physics of the component
biological structures and systems that define the limits of life
[78,79].
6. Synthesis and future opportunities
DCO is synthesizing and integrating research across its four
Science Communities to realize a new understanding of deep car-
bon science and fully capture DCO’s achievements. This synthesis
process aims to elevate the collaborative efforts of the global
research initiative. Synthesis products and activities include
cross-community research projects, such as Biology Meets Subduc-
tion and Carbon Mineral Evolution, as well as workshops, meet-
ings, visualizations, special issues of journals, and books. The
culmination of these activities will occur at an international con-
ference, Deep Carbon 2019: Launching the Next Decade of Deep
Carbon Science.
To help launch the next decade of deep carbon science, DCO sci-
entists are developing a broad portfolio of activities that will
extend beyond the culmination of the initial decadal program in
2019. A biennial Gordon Research Conference on Deep Carbon
Science is planned as a sustainable successor to DCO international
science meetings. A biennial Gordon Research Seminar on Deep
Carbon Science for early career scientists could become a successor
to DCO Summer Schools and DCO Early Career Scientist Work-
shops. Carbonates at High Pressures and Temperatures (CarboPaT),
a research consortium supported by the German Research Founda-
tion to study carbonates at extreme conditions, will continue to
provide a platform for deep carbon science in Germany. In the
United Kingdom, the Natural Environment Research Council has
established a research program on Volatiles, Geodynamics, and
Solid Earth Controls on the Habitable Planet. Science for Clean
Energy is a European consortium led by DCO researchers with sup-
port from the European Union’s Horizon 2020 program. The next
decade of deep life research will be facilitated by a new Interna-
tional Center for Deep Life Investigation at Shanghai Jiao Tong
University in China as well as a cluster of excellence titled The
Ocean Floor—Earth’s Uncharted Interface in Germany. These and
other initiatives will help propel the next decade of deep carbon
science.
7. Conclusion
In 2009, DCO was an ambitious experiment in scientific pro-
grams with no guarantee of success. Since then, DCO has evolved
into a network of more than 1200 scientists that spans the globe
and transcends traditional scientific disciplines. DCO is a science
incubator that has launched new research groups, science commu-
nities, international scientific collaboration and partnerships,
major research projects, field expeditions, scientific instruments,
and companies. Perhaps most importantly, DCO has built an
enduring legacy in its diverse, dynamic, and collaborative com-
munity of interdisciplinary scientists. DCO’s management and
community-building innovations are keys to the program’s scien-
tific success. Based on its success in achieving fundamental
advances in deep carbon science, DCO may serve as an effective
model for tackling large-scale, interdisciplinary, and international
science questions.
Acknowledgements
The Deep Carbon Observatory would not have been possible
without generous, long-term support from the Alfred P. Sloan
Foundation. Deep carbon science has advanced through the
collective efforts of many other organizations, including: the
Canadian Space Agency; Canada Research Chairs Program;
Carnegie Institution for Science; Chinese Academy of Sciences;
Conseil Régional d’Ile de France; Deutsche Forschungsgemein-
schaft; European Research Council; European Commission; Inter-
national Continental Scientific Drilling Program; International
Ocean Discovery Program; Japan Agency for Marine-Earth Science
and Technology; Japan Society for the Promotion of Science;
Ministry of Education, Culture, Sports, Science, and Technology
of Japan; Natural Sciences and Engineering Research Council of
Canada; Russian Ministry of Science and Education; Swiss
National Science Foundation; UK Natural Environment Research
Council; US National Science Foundation; US Department of
Energy; and US National Aeronautics and Space Administration.
We have benefited enormously from the members of the DCO
Executive Committee, Scientific Steering Committees, and other
leadership groups, especially the chairs and co-chairs of the
Scientific Steering Committees: Isabelle Daniel, Marie Edmonds,
Erik Hauri, Kai-Uwe Hinrichs, Craig Manning, Wendy Mao,
Bernard Marty, Mitch Sogin, and Edward Young.
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