ESSI Newsletter
Issue 4
Spring 2017
Earth Surface Science Institute
SCHOOL OF EARTH AND ENVIRONMENT
INSIDE THIS ISSUE
The first few months of 2017 have been highly successful
for ESSI. Several high profile papers have been published
in distinguished international journals, including Nature,
Proceedings of the Natural Academy of Sciences and Nature
Communications, all of which received extensive media
coverage. This media coverage was enhanced by insightful
radio interviews with Dr Tracy Aze and Dr Christian Maerz. In
addition, we are pleased to have received significant reseacrh
funding from the European Research Council and the Natural
Environment Research Council. All in all, a great start to 2017!
PUBLICATIONS
Highlights from the past 6 months
Pages 2 - 5
AWARD WINNERS
Celebrating our achievements
Page 5
NEW RESEARCH PROJECTS
Read about some of our lates
funding success
Pages 6 - 7
Simon Poulton, Institute Director
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RECENT KEY PUBLICATIONS
•
Daines SJ; Mills BJW; Lenton TM Atmospheric oxygen regulation at low Proterozoic levels by incomplete
oxidative weathering of sedimentary organic carbon, Nature Communications, 8, doi: 10.1038/ncomms14379
•
Dodd MS; Papineau D; Grenne T; Slack JF; Rittner M; Pirajno F; O’Neil J; Little CTS Evidence for early life in
Earth”s oldest hydrothermal vent precipitates, Nature, 543, pp.60-64. doi: 10.1038/nature21377
•
Hill DJ; Bolton KP; Haywood AM Modelled ocean changes at the Plio-Pleistocene transition driven by Antarctic
ice advance., Nature Communications, 8, pp.14376. doi: 10.1038/ncomms14376
•
Ivanovic RF; Gregoire LJ; Wickert AD; Valdes PJ; Burke A Collapse of the North American ice saddle 14,500
years ago caused widespread cooling and reduced ocean overturning circulation, Geophysical Research
Letters, 44, pp.383-392. doi: 10.1002/2016GL071849
•
Sun YD; Liu XT; Yan JX; Li B; Chen B; Bond DPG; Joachimski MM; Wignall PB; Wang X; Lai XL Permian
(Artinskian to Wuchapingian) conodont biostratigraphy in the Tieqiao section, Laibin area, South China,
Palaeogeography, Palaeoclimatology, Palaeoecology, 465, pp.42-63. doi: 10.1016/j.palaeo.2016.10.013
•
Zerkle AL; Poulton SW; Newton RJ; Mettam C; Claire MW; Bekker A; Junium CK Onset of the aerobic
nitrogen cycle during the Great Oxidation Event., Nature, 542, pp.465-467. doi: 10.1038/nature20826
•
Stockdale A; Krom MD; Mortimer RJG; Benning LG; Carslaw KS; Herbert RJ; Shi Z; Myriokefalitakis S;
Kanakidou M; Nenes A Understanding the nature of atmospheric acid processing of mineral dusts in supplying
bioavailable phosphorus to the oceans, Proceedings of the National Academy of Sciences of the United States
of America, 113, pp.14639-14644. doi: 10.1073/pnas.1608136113
Study breathes new life into 2.3 billion year old
‘Great Oxidation Event’
Study breathes new life into 2.3 billion year old ‘Great
Oxidation Event’
New research based on Precambrian rocks provides
insight into how life evolved alongside changes in the
chemistry of Earth’s surface.
The study, published in Nature, examined geochemical
records of Earth’s ‘Great Oxidation Event’ 2.3 billion
years ago, and captured for the first time the response of
the nitrogen cycle to this major transition in the planet’s
surface environment.
Our researchers played a key role in the study, which
fills a ~400 million year gap in geochemical records
across a dramatic change that occurred halfway through
Earth’s history, when oxygen first accumulated in the
atmosphere.
Study co-author Dr Robert Newton, said: “The rise
of atmospheric oxygen is thought to be an essential
ingredient for the development of multicellular life on
Earth, and ultimately our own evolution. The nitrogen
isotope analyses we performed at Leeds as part of
this project are one of the few ways we can study the
operation of the nitrogen cycle in the past.”
Nitrogen is an essential element in all living organisms,
required for the formation of proteins, amino acids, DNA
and RNA. As a key ‘nutrient’, nitrogen therefore exerts
a control on global primary productivity, which in turn
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regulates climate, weathering, and the amount of oxygen
at Earth’s surface.
Despite the importance of nitrogen to life, major gaps
existed in the previous geochemical records of how the
nitrogen cycle responded to critical events in Earth’s
history. The result of the research is a set of highresolution records of nitrogen isotopes in sedimentary
rocks that record the environmental conditions during the
Great Oxidation Event. These detailed records document
the immediate onset of a modern-style nitrate-driven
ecosystem, appearing simultaneously with the first
evidence for oxygen in the atmosphere.
Study co-author Professor Simon Poulton, said: “The
rocks we studied came from the National Core Library
in Donkerhoek, South Africa. They are unique, in that
they record the precise moment the Earth’s atmosphere
became oxygenated. Because the rocks were formed
in a marine environment we were able to use advanced
geochemical techniques to show the rapid response of
the shallow ocean to atmospheric oxygenation. This was
a monumental transition in the history of the Earth.”
Study lead author Dr Aubrey Zerkle from the School of
Earth and Environmental Sciences at the University of St
Andrews said: “The ‘Great Oxidation Event’ was arguably
the most dramatic environmental change in Earth history.” Dr Zerkle explained that catastrophic upheavals in past
surface conditions such as these provided a critical
window for scientists to study how the biosphere
responds to environmental change. She said that
understanding how life on this planet responded to
geochemical changes in the past will help us to more
clearly predict the response to future changes, including
Earth’s warming climate. It will also inform our search for
habitable planets in other solar systems.
Dr Zerkle said: “Our data shows the first occurrence of
widespread nitrate, which could have stimulated the rapid
diversification of complex organisms, hot on the heels of
global oxygenation. The building blocks were apparently
in place, the question that remains is why eukaryotic
evolution was seemingly stalled for another billion or
more years.”
This study was funded by the Natural Environment
Research Council and included researchers from the
University of St Andrews, the University of Leeds,
the University of California, Riverside, and Syracuse
University.
Antarctica major driver in past ocean changes
A new study published recently in Nature
Communications highlights the importance of Antarctic
ice sheet advance in causing changes in the Pacific
ocean during the decent into the ice ages, at the PlioPleistocene Transition (3.2 to 2.6 million years ago). One of the dominant changes occurring during this
transition was the shift to large ice sheets in the Northern
Hemisphere. However, the ocean was also undergoing
significant changes. Using global climate models set up
to simulate past environments, researchers in the Institute
of Climate and Atmospheric Science and Earth Surface
Science Institute showed that there is a link between
ice presence in the Pacific sector of Antarctic and the
formation of modern North Pacific Deep Water.
Dr. Daniel Hill, the lead author of the study says that they
have demonstrated for the first time that ice advance after
a warm period in the Pliocene is the main reason that
Pacific Ocean deep water circulation increased during
this time. This study also highlights the success and potential for
our NERC Research Experience Placements within the
School of Earth and Environment. Kevin Bolton, a coauthor on the study, analyzed the multi-model component
of the study as part of his NERC Research Experience
Placement within the School. Kevin has now gone on
to study for a PhD at Environment and Sustainability
Institute, College of Engineering, Mathematics and
Physical Sciences, University of Exeter, Penryn Campus,
Cornwall.
World’s oldest fossils unearthed
Remains of microorganisms at least 3,770 million years
old have been discovered - providing direct evidence of
one of the oldest life forms on Earth. An international research team has found tiny filaments
and tubes formed by bacteria encased in quartz layers
in the Nuvvuagittuq Supracrustal Belt (NSB), Quebec,
Canada, which contains some of the oldest sedimentary
rocks known on Earth. A study, published in Nature,
describes the discovery and the detailed analysis of the
remains undertaken by the team from the University
of Leeds, UCL, the Geological Survey of Norway, U.S.
Geological Survey, the University of Western Australia,
and the University of Ottawa. Study co-author, Dr Cris Little played an important role
in determining that the discovered filaments and tubes
were made by biological organisms rather than through
non-biological processes, like temperature and pressure
changes in the rock. Dr Little said: “These fossils are made of haematite –
a form of iron oxide or ‘rust’ and they have the same
characteristic branching of iron-oxidising bacteria found
near other hydrothermal vents today. The tubes and
filaments were found inside structures called concretions
which are believed to be products biological decay.
When we compared these specimens with those found
in younger rocks from Norway, the Great Lakes area of
North America and Western Australia we found them to
be mineralogically identical. “The fact that we found these fossils in the NSB, which is
believed to have formed part of a habitat for Earth’s first
life forms between 3,770 and 4,300 million years ago,
suggests these are the remains of one of Earth’s oldest
life forms.” Prior to this discovery, the oldest microfossils reported
were found in Western Australia and dated at 3,460
million years old but some scientists think they might be
of non-biological origins. 3
“Many regions of the globe
are limited by the amount of
phosphorous available, so pollution
can have a very important impact on
marine ecosystems.”
Fellow author Michael Krom, an
Emeritus Professor of ESSI, now
at the University of Haifa, added:
“If more carbon dioxide is taken up
by marine plants due to fertilisation
from acidified dust, it is possible
that air pollution may have been
inadvertently reducing the amount
of greenhouse gases, while at the
same time increasing the amount of
plants and even fish in areas such as
the Mediterranean Sea.”
Haematite tubes from the NSB hydrothermal vent deposits that represent the oldest
microfossils and evidence for life on Earth. The remains are at least 3,770 million years old.
Photo by Matthew Dodd. The newly discovered haematite
structures were discovered alongside
graphite and minerals like apatite
and carbonate which are found in
biological matter including bones and
teeth and are frequently associated
with fossils. The researchers also found that
the fossils co-occur with spheroidal
formations that usually contain
fossils in younger rocks, suggesting
that the NSB haematite most likely
formed when bacteria that oxidised
iron for energy were fossilised in the
rock. Study first author, Matthew Dodd
from UCL Earth Sciences and the
London Centre for Nanotechnology,
said: “Our discovery supports
the idea that life emerged from
hot, seafloor vents shortly after
planet Earth formed. This speedy
appearance of life on Earth fits
with other evidence of recently
discovered 3,700 million year old
sedimentary mounds that were
shaped by microorganisms “These discoveries demonstrate
life developed on Earth at a time
when Mars and Earth had liquid
water at their surfaces, posing
exciting questions for extra-terrestrial
life. Therefore, we expect to find
evidence for past life on Mars 4,000
million years ago, or if not, Earth may
have been a special exception.” 4
The climate-changing desert
dust fertilising our oceans
The way in which man-made acids
in the atmosphere interact with the
dust that nourishes our oceans has
been quantified by scientists for the
first time.
In the international study led
by two of the School of Earth &
Environment’s Institutes - Earth
Surface Science Institute and
Institute for Climate & Atmospheric
Science , researchers have
pinpointed how much phosphate
“fertiliser” is released from dust
depending on atmospheric acid
levels.
Phosphorus is an essential nutrient
for all life, and when it falls into
the ocean, it acts as a fertiliser
that stimulates the growth of
phytoplankton and marine life.
The new study allows scientists
to quantify exactly how much
phosphate “fertiliser” is released from
dust depending on atmospheric acid
levels.
Dr Anthony Stockdale, from ESSI,
is lead author of the study. He
said: “The ability to quantify these
processes will now allow models
to predict how pollution on a global
scale modulates the amount of
fertiliser released in airborne dust
before it falls into the oceans.
Co-author Professor Athanasios
Nenes, of Georgia Institute of
Technology, said the implications
went beyond the carbon cycle and
climate.
“The Mediterranean is one of many
locations of the globe where pollution
and dust mix frequently,” he said.
“This study points to one more way
this interaction can affect marine life
and the 135 million inhabitants of its
coastline.”
Professor Krom added: “The next
step is to develop models which
include this new pathway for
increased plant growth in the ocean,
in order to fully determine the effect
on marine ecosystems and Earth’s
climate, considering a full suite of
chemical, physical and biochemical
processes.”
Phosphorus is one of the essential
elements for life and is a critical
component of building blocks such
as DNA. Dusts, from deserts such as
the Sahara, are an important source
of phosphorus to Earth’s oceans.
The mineral-containing dust is
generated in copious amounts during
storms and is found throughout the
atmosphere.
Most of the phosphorus in this
dust is in an insoluble form that the
microscopic plants of the oceans –
phytoplankton and diatoms – cannot
get at.
Known as apatite, the phosphorus in
the dust is similar to the substance
found in our teeth and bones.
Acids can be released naturally into the atmosphere from volcanic eruptions and from living organisms. But the
burning of fossil fuels is currently the most significant source of atmospheric acids.
In the same way that acid produced by the bacteria in our mouths can cause tooth decay, so can acids in the
atmosphere dissolve apatite and turn it into a form of phosphorus that can be used by marine organisms, the study
authors said.
Professor Ken Carslaw (ICAS), who has
worked on the long running project, said “These
exciting results are the result of years of fruitful
collaboration between Earth scientists and
atmospheric scientists and promise to result in
more ground-breaking science.”
As well as researchers from Leeds, Georgia and
Haifa, experts from three institutions in Greece,
one in Israel, one in Germany and two others
in the UK worked on the findings, published in
Proceedings of the National Academy of Science
of the USA. The University of Leeds team was
funded by The Leverhulme Trust.
AWARD WINNERS
Professor Paul Wignall to
receive EGU Medal
ESSI is very pleased to congratulate
Professor Paul Wignall on the
announcement that he will be
the recipient of the European
Geosciences Union’s Jean Baptiste
Lamarck Medal 2017.
The Jean Baptiste Lamarck Medal is
awarded in recognition of scientific
achievement in Stratigraphy,
Sedimentology and Palaeontology.
The awardees alternate each year
between these three subdivisions.
Professor Wignall has received this
award for his exceptional contribution
to the field of Palaeontology.
Professor Paul Wignall’s has made
an important contribution to our
understanding of mass extinction
events in the geological record. He
is well known for his approach to
unpicking
the fossilJohn
recordMarsham
at times
Photo credit:
of biotic crisis and the role of global
warming and marine anoxia in the
Permian-Triassic mass extinction.
More recently he has carried out
important work testing the link
between mass extinctions and
large igneous province volcanism,
particularly between the Emeishan
Traps and the Middle Permian
extinction, and the Central Atlantic
Magmatic Province and end-Triassic
extinction. The work on the Middle
Permian event has helped to elevate
this previously little known extinction
to its place amongst the “big 5”.
He has taught and inspired
numerous Undergraduate students
and supervised 25 PhD students
during his time at the University of
Leeds. Additionally he has provided
support to the greater community,
sitting on the panel of the UK’s
Research Excellence Framework
Review Panel for Earth Sciences
(2014), acting as President of
the Yorkshire Geological Society
(2009-10), as Managing Editor
of Earth Science Reviews, and
sitting on the editorial board of
Geology, Geological Magazine,
Palaeogeography Palaeoclimatology
Palaeoecology, Geobiology, and
Chemical Geology.
Professor Wignall receives his award
at the EGU general assembly in
Vienna in April 2017, and during the
award ceremony Professor Wignall
Photo credit: John Marsham
will be invited to give his medal
lecture.
The Top 60 Papers from the
First 60 Years of L&O
A highly cited 1991 paper by Cohen
Group Emeritus Professor Michael
Krom has been included in a 60th
anniversary issue of the journal
Limnology and Oceanography
that covers the 10 most influential
papers from each decade since the
journals inception. Phosphorus
limitation of primary productivity
in the eastern Mediterranean Sea
(1991) M.D Krom, N. Kress, S.
Brenner, L.I. Gordon. Limnology
and Oceanography, 36, pp 424, doi
10.4319/lo.1991.36.3.0424
Harwood Award
Congratulations to PhD student
Autumn Pugh who has been given
the Harwood Award from the British
Sedimentological Research Group
. This award, which is in memory of
scientist Gill Harwood’s contribution
to evaporate and carbonate
sedimentology, is offered to female
sedimentologists to assist them
in carrying out fieldwork or attend
international meetings Autumn
will be using the award to support
her attendance at the 2017 Flugel
Course on carbonate microfacies
analysis in Erlangen, Germany.
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OUR SCIENTISTS AT THE AGU FALL MEETING
The School of Earth and Environment was strongly represented at the 2016 AGU Fall Meeting in San Francisco which
took place 12th – 16th December. The Institute of Geophysics (IGT), Institute for Climate and Atmospherics Science
(ICAS), Earth Surface Science Institute (ESSI) and the Institute for Applied Geosciences (IAG) all had members delivering presentations, running scientific sessions and showing posters of their research findings.
Aisling Dolan, Alan Haywood, Ben Mills and PhD student Caroline Prescott were representing ESSI. Ben Mills
and Caroline Prescott both gave talks, whilst Aisling Dolan convened two sessions and Prof Haywood presented three
posters during the meeting.
NEW RESEARCH FUNDING
Caroline Peacock receives
ERC grant
We are very pleased to announce
that Dr Caroline Peacock has
been awarded an ERC Consolidator
Grant in order to study “The Role
of Minerals in the Oceanic Carbon
Cycle”.
The grant, which is worth
approximately €2 million, will start
later next year and run for 5 years.
It will employ 2 PDRA’s and 3 PhD
students in SEE, who will be part
of the Cohen Group. The research
team also includes Dr Clare Woulds
from the School of Geography,
University of Leeds, and Dr Andrew
Dale at GEOMAR in Kiel, Germany.
The overall aim of this work is to
study the role of reactive marine
minerals in the oceanic carbon
cycle, specifically their role in the
preservation of organic carbon in
marine sediments and seawater.
The oceanic carbon cycle is
fundamentally important for
regulating the Earth system because,
in sediments and seawater, the
balance between the degradation
and preservation of organic carbon
exerts a first order control on
atmospheric carbon dioxide and
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oxygen. These gases have mediated
global climate, planetary oxygenation
and Earth’s habitability through
geologic time, while increasing
carbon dioxide levels now present a
major climate threat. In sediments,
organic carbon can be preserved
over millions of years, while in
seawater, a dissolved form of
recalcitrant organic carbon has been
recently recognised as critical to
carbon storage over anthropogenic
timescales. However, both
sedimentary and seawater organic
carbon are derived from living
organisms, and should therefore be
easily degraded. Their persistence
in the oceans is therefore one of the
most enduring paradoxes in marine
biogeochemistry.
This work will explore the extent to
which reactive fine-grained minerals,
including clays and iron (hydr)oxides,
are able to protect organic carbon
from microbial degradation, and
thus promote carbon preservation in
marine sediments, and also whether
these minerals can transform
otherwise labile organic molecules
into microbially resistant forms,
thus generating recalcitrant organic
carbon in seawater. During the grant
Dr Peacock will quantify the role
of minerals in the preservation of
organic carbon for the first time, by
combining cutting-edge molecularlevel techniques with the first
comprehensive and fully integrated
experimental and modelling
campaign, to determine in detail the
exact mechanisms responsible for
the interaction of organic carbon
with minerals, and its subsequent
degradation and preservation
behaviour.
Dr Peacock commented ‘Overall, I
hope that with my newly assembled
research team we can make a
major contribution to understanding
and predicting organic carbon
preservation, and thus the Earth’s
carbon cycle in modern and ancient
environments.’
As a recipient of the European
Association of Geochemistry’s 2015
Houtermans award, Dr Peacock is
already well recognised for her work on the reactivity and
cycling of metals and nutrients in marine and terrestrial
environments. Additionally her outstanding contributions
to science were recognised by the University of Leeds
when she received their Women of Achievement award
this year. The School of Earth and Environment are very
pleased to be able to congratulate Caroline in receiving
this prestigious grant and wish her and her team the best
of luck with their work.
NERC Research Project “The Changing Arctic
Ocean Seafloor”
NERC have announced their programme to investigate
the impact of climate change and diminishing sea ice on
the marine environments of the Arctic Ocean. NERC’s
£10 million investment has funded four projects which will
begin in February and run for four years.
Dr Christian März will be the Principal Investigator
on one of these projects, “The Changing Arctic Ocean
seafloor (ChAOS)”. This £2.1 million project, with ~£500k
coming to the University of Leeds, is a collaboration
of geochemists, biologists and modellers at eight UK
research institutes. As one of the four consortium projects
to study the effects of climate change and retreating sea
ice on Arctic Ocean biology and biogeochemistry, ChAOS
will focus on how changing conditions impact biological
communities, biogeochemical processes and ecosystems
in the seafloor environment. The Leeds group will apply
cutting edge techniques to study organic carbon burial
facilitated by metal oxides as well as nutrient recycling
from Arctic Ocean sediments, both on natural samples
and controlled laboratory experiments. The project will
also include several expeditions to the Arctic Ocean on
board the ice-strengthened RRS James Clark Ross, the
first of which will be in the summer of 2017.
NERC BETR Scheme
In NERC’s BETR scheme ESSI researchers secured two
out of the three grants funded. Paul Wignall’s project
(Eco-PT) will look at the causes of the Permo-Triassic
mass extinction, especially for terrestrial life, and the
nature of the ensuing recovery. The majority of the £1.5
million grant will be spent at Leeds and will involve
sulphur geochemistry (Rob Newton), climate modelling
(Dan Hill, Alan Haywood) and ecosystem modelling
(Alex Dunhill) studies in collaboration with colleagues at
Nottingham, Bristol, Birmingham and Oxford Brookes and
at several institutes in China. This is probably the largest
mass extinction research team ever assembled.
IN THE NEWS
Paul Wignall appeared on the Channel
4 programme Walking Through Time in
October talking about ancient climate
catastrophes and the evidential impact on
sea life.
Cris Little was quoted in The Independent
on the subject of how to say ‘diplodocus’ in a
piece marking ‘Dippy the diplodocus’ last day
at the Natural History Museum.
Christian März was a guest on the Paul
Hudson Weather show on Radio Leeds at
the end of February to talk about his NERC
funded ChAOS project looking into the
changing Arctic Ocean floor.
Simon Poulton’s work proposing a new
contributing cause for the Great Oxidation
Event 2.4 billion years ago was reported on
in several media outlets following the papers
publication in Proceedings of the Natural
Academy of Sciences in March.
Tracy Aze was a guest on BBC Radio 4 in
March discussing the high temperatures
which marked the end of the Paleocene and
start of the Eocene periods, about 50 million
years ago.
Cris Little worked with an international team
of researchers who discovered the remains
of microorganism at least 3,770 million
years old; thought to be the World’s oldest
fossil. Following the publication of this work
in Nature this was widely reported on in the
media.
Simon Poulton is part of the second BETR funded team
who were awarded £1.5 million to study perturbations
to the Earth System and biosphere during the Proterozoic-Phanerozoic transition 540 million years ago. The
researchers will investigate the environmental conditions
and drivers that led to the sudden appearance of the
first complex life in the fossil record - a phenomenon
known as Darwin’s Dilemma. This project includes CoPI’s at UCL, Bristol, BGS and Exeter, as well as several
world-leading groups in China.
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Newsletter compiled by Claire McLoughlin
School of Earth and Environment
Institute Director, Professor Simon Poulton
School of Earth and Environment
University of Leeds
Leeds, LS2 9JT
www.see.leeds.ac.uk/research/essi/
Twitter @ESSILeeds
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