Katherine Richardson

University of Copenhagen · Center for Macroecology, Evolution and Climate

Purpose Nitrogen emissions from human activities are contributing to elevated levels of eutrophication in coastal ecosystems. Mechanisms involved in marine eutrophication show strong geographical variation. Existing life cycle impact assessment (LCIA) and absolute environmental sustainability assessment (AESA) methods for marine eutrophication do n...

Subsurface accumulations of chlorophyll, also known as deep chlorophyll maxima (DCMs), have been observed in the Southern Ocean. DCMs can coincide with deep biomass maxima (DBMs). Their formation and maintenance are still a topic of debate, as is their contribution to column-integrated phytoplankton biomass and net primary productivity (NPP). Here...

It has been shown that mid-water column turbulence leads to elevated vertical nutrient flux at the shelf edge in the northeastern North Sea. Here, we demonstrate that phytoplankton communities in this region tended to be dominated by larger cells (estimated from percentage of chlorophyll captured on a 10 µm filter) than beyond the shelf edge. F v /...

The Anthropocene signifies the start of a no-analogue trajectory of the Earth system that is fundamentally different from the Holocene. This new trajectory is characterized by rising risks of triggering irreversible and unmanageable shifts in Earth system functioning. We urgently need a new global approach to safeguard critical Earth system regulat...

This planetary boundaries framework update finds that six of the nine boundaries are transgressed, suggesting that Earth is now well outside of the safe operating space for humanity. Ocean acidification is close to being breached, while aerosol loading regionally exceeds the boundary. Stratospheric ozone levels have slightly recovered. The transgre...

Phytoplankton community composition is important in establishing ecosystem structure and function. Intuitively, we recognize that water movements must be important for modifying spatial gradients and plankton diversity. However, identifying boundaries and exchange between habitats in the open ocean is not straightforward. Here, we use the abundance...

The Earth is a complex system, and its overall condition (state) at any time is determined by Geosphere-Biosphere interactions. The state of the system as a whole changes over time, e.g., ice ages to interglacials. We, therefore, consider system state as a descriptor of, for example, climate. The timescales of the processes driving the interactions...

Earth system scientist with passion for people and planet.

The ocean plays a central role in modulating the Earth’s carbon cycle. Monitoring how the ocean carbon cycle is changing is fundamental to managing climate change. Satellite remote sensing is currently our best tool for viewing the ocean surface globally and systematically, at high spatial and temporal resolutions, and the past few decades have see...

Combining information on the vertical distribution of nutrients and remote sensing can potentially improve estimates of ocean primary production (PP). Here, we employ in situ observations of chlorophyll a and nitrate from biogeochemical Argo floats deployed in the North Atlantic together with remote sensing to estimate PP and compare these results...

The main strait (Great Belt) connecting the North Sea and the Baltic Sea constitutes a quasi-stationary front and exposes phytoplankton to various degrees of water column mixing. Here, we examine phytoplankton community distributions (using the cell abundance of 4 readily identifiable diatoms) and estimate new production along the strait during ear...

Zooplankton grazing at similar nutrient levels is generally regarded as lower in brackish than in freshwater lakes, but experimental evidence of this is lacking. Accordingly, we conducted short-term zooplankton grazing experiments in bottles with water from 12 Danish brackish lakes covering a large gradient in salinity (0.3–17.4‰) and nutrient conc...

Marine eutrophication and hypoxia caused by excess nutrient availability is a growing environmental problem. In this study, we explore marine nitrogen enrichment in the context of Absolute Environmental Sustainability Assessment (AESA), a method combining life cycle assessment (LCA) with environmental boundaries aiming to compare environmental impa...

Den bæredygtige stat skal i sit virke respektere, at mennesker ikke er hævet over natur, men er en del af ”Jordens økosystem”. Det betyder bl.a., at eksternaliteter, herunder evt. miljøudfordringer, der opstår som følge af samfundets aktiviteter, ikke kan behandles i isolation. En ”klimalov” skal f.eks. også tage hensyn til andre menneskelige påvir...

Primary production (PP) in the sub-polar region appears to be important for ocean carbon uptake but how the different water masses contribute to the PP occurring here has not yet been described. Using two models based on satellite observations of surface chlorophyll, light and temperature, seasonal patterns in the distribution of PP are shown here...

Since the article “Primary Production, an Index of Climate Change in the Ocean: Satellite-Based Estimates over Two Decades” by Kulk et al. [1] was published, we discovered an error in the code of the primary production model, which crept in when the code was updated from the original version described by Platt and Sathyendranath (1988), Sathyendran...

The Earth's oceans are one of the largest sinks in the Earth system for anthropogenic CO2 emissions, acting as a negative feedback on climate change. Earth system models project that climate change will lead to a weakening ocean carbon uptake rate as warm water holds less dissolved CO2 and as biological productivity declines. However, most Earth sy...

The element carbon plays a central role in climate and life on Earth. It is capable of moving among the geosphere, cryosphere, atmosphere, biosphere and hydrosphere. This flow of carbon is referred to as the Earth's carbon cycle. It is also intimately linked to the cycling of other elements and compounds. The ocean plays a fundamental role in Earth...

Over the past century, the total material wealth of humanity has been enhanced. However, in the twenty-first century, we face scarcity in critical resources, the degradation of ecosystem services, and the erosion of the planet’s capability to absorb our wastes. Equity issues remain stubbornly difficult to solve. This situation is novel in its speed...

Environmental sustainability boundaries can help us navigate a sustainable development trajectory, by evaluating environmental performance of current actions in relation to such boundaries. However, current definitions of environmental sustainability boundaries have shortcomings when used in environmental assessments. The shortcomings include consi...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The Earth’s oceans are one of the largest sinks in the Earth system for anthropogenic CO2 emissions, acting as a negative feedback on climate change. Earth system models predict, though, that climate change will lead to a weakening ocean carbon uptake rate as warm water holds less dissolved CO2 and biological productivity declines. However, most Ea...

New production of organic matter from photosynthesis based on “new” nitrate transported into the illuminated surface layer fuels temperate ecosystems during periods of stratification when surface waters are nutrient limited. Published observations from the northeastern North Sea show a large spatial heterogeneity in vertical nitrate fluxes and sugg...

Primary production by marine phytoplankton is one of the largest fluxes of carbon on our planet. In the past few decades, considerable progress has been made in estimating global primary production at high spatial and temporal scales by combining in situ measurements of primary production with remote-sensing observations of phytoplankton biomass. O...

The planetary boundary framework presents a ‘planetary dashboard’ of humanity’s globally aggregated performance on a set of environmental issues that endanger the Earth system’s capacity to support humanity. While this framework has been highly influential, a critical shortcoming for its application in sustainability governance is that it currently...

Earth System Science (ESS) is a rapidly emerging transdisciplinary endeavour aimed at understanding the structure and functioning of the Earth as a complex, adaptive system. Here, we discuss the emergence and evolution of ESS, outlining the importance of these developments in advancing our understanding of global change. Inspired by early work on b...

Individual organisms on land and in the ocean sequester massive amounts of the carbon emitted into the atmosphere by humans. Yet the role of ecosystems as a whole in modulating this uptake of carbon is less clear. Here, we study several different mechanisms by which climate change and ecosystems could interact. We show that climate change could cau...

The growing threat of abrupt and irreversible climate changes must compel political and economic action on emissions. The growing threat of abrupt and irreversible climate changes must compel political and economic action on emissions. A plane flying over a river of meltwater on glacier in Alaska

Mountain regions are unusually biodiverse, with rich aggregations of small-ranged species that form centers of endemism. Mountains play an array of roles for Earth’s biodiversity and affect neighboring lowlands through biotic interchange, changes in regional climate, and nutrient runoff. The high biodiversity of certain mountains reflects the inter...

Dominant research modes are not enough to guide the societal transformations necessary to achieve the 2030 Agenda. Researchers, practitioners, decision makers, funders and civil society should work together to achieve universally accessible and mutually beneficial sustainability science.

In this study, the inverted trophic hypothesis was tested in the freshwater fish communities of a reservoir. The distribution of fish species in three freshwater habitats in the Jurumirim Reservoir, Brazil, was examined using both species richness and the relative proportions of different trophic groups. These groups were used as a proxy for functi...

Phalacroma currently comprises 69 species of mostly marine heterotrophic dinophysoids. With a round cell body and short sulcal and cingular lists, Phalacroma spp. have a simple morphology compared to other dinophysoid genera. Therefore, species identification is not always a trivial matter. A few Arctic species have been described and, with the exc...

New production, i.e. that driven by allochthonous nutrient inputs, is the only form of primary production that can lead to net increases in organic material and is, therefore, important for understanding energy flow in marine ecosystems. The spatial distribution of new production is generally, however, not well known. Using data collected in July 2...

An absolute environmental sustainability assessment (AESA) addresses whether a production or consumption activity can be considered environmentally sustainable in an absolute sense. This involves a comparison of its environmental pressure to its allocated environmental carrying capacity. AESA methods have been developed in multiple academic fields,...

New production, i.e., that driven by allochthonous nutrient inputs, is the only form of primary production that can lead to net increases in organic material and is, therefore, important for understanding energy flow in marine ecosystems. The spatial distribution of new production is generally, however, not well known. Here, using data collected in...

We explore the risk that self-reinforcing feedbacks could push the Earth System toward a planetary threshold that, if crossed, could prevent stabilization of the climate at intermediate temperature rises and cause continued warming on a "Hothouse Earth" pathway even as human emissions are reduced. Crossing the threshold would lead to a much higher...

Changes to climate–carbon cycle feedbacks may significantly affect the Earth system's response to greenhouse gas emissions. These feedbacks are usually analysed from numerical output of complex and arguably opaque Earth system models. Here, we construct a stylised global climate–carbon cycle model, test its output against comprehensive Earth system...

© 2018 Elsevier Ltd To enable quantifying environmental performance of products and technologies in relation to Planetary Boundaries, there is a need for life-cycle impact assessment (LCIA) methods which allow for expressing indicators of environmental impact in metrics corresponding to those of the control variables in the Planetary Boundaries fra...

Owing to the dynamic nature of nutrient-phytoplankton interactions, ambient macronutrient concentrations reveal little about the impact of nutrient availability on phytoplankton biomass and community composition at any given point in time or space. Here, however, we examine a global dataset (n = 262) where phytoplankton community structure and biom...

Biodiversity is a multifaceted concept, yet most biodiversity studies have taken a taxonomic approach, implying that all species are equally important. However, species do not contribute equally to ecosystem processes and differ markedly in their responses to changing environments. This recognition has led to the exploration of other components of...

Overview of species aggregations into multi-species groups. (DOCX)

Summary statistics of natural and anthropogenic environmental covariates used in the relative variable importance analysis. (DOCX)

Relative biomass of all species. (DOCX)

Ratios of TRic to SRic, and TEve to SEve over the study period. (DOCX)

Abundance to biomass-conversion parameters. (DOCX)

Trait information on all species. (DOCX)

Temporally averaged values of natural and anthropogenic environmental covariates. (XLSX)

Values of biodiversity indicators per year per ICES rectangle. (XLSX)

Biomass of species per year per ICES rectangle. (XLSX)

Changes to climate-carbon cycle feedbacks may significantly affect the Earth System’s response to greenhouse gas emissions. These feedbacks are usually analysed from numerical output of complex and arguably opaque Earth System Models (ESMs). Here, we construct a stylized global climate-carbon cycle model, test its output against complex ESMs, and i...

Photosynthetic O 2 production can be an important source of oxygen in sub-surface ocean waters especially in permanently stratified oligotrophic regions of the ocean where O 2 produced in deep chlorophyll maxima (DCM) is not likely to be outgassed. Today, permanently stratified regions extend across approximately 40% of the global ocean and their e...

Some phytoplankton species have been predicted to contribute more to the biological pump than others. In this study, we examine the potential of species distribution modelling (SDM) for describing current and predicting future global distributions of two phytoplankton species: the diatom Chaetoceros diadema and the coccolithophore Emiliania huxleyi...

Aim To identify key environmental factors associated with local fish species richness across a large tropical marine region. Location Wider Caribbean region. Methods Species richness estimates were based on a sightings database covering the wider Caribbean region. Environmental variables considered were distance to key habitats, habitat area, tem...

The seasonal variation in phytoplankton activity is determined by analysing 1385 primary production (PP) profiles, chlorophyll a (Chl) concentration profiles and phytoplankton carbon biomass concentrations (C) from the period 1998–2012. The data was collected at six different stations in the Baltic Sea transition zone (BSTZ) which is a location wit...

Global and regional ocean primary production estimates are highly dependent on assumptions concerning the photosynthetic potential of the resident phytoplankton communities. Little is known, however, about global patterns in the distribution of photosynthetic potential and their causes. Here, we review existing literature reporting photosynthetic c...

Impacts on the environment from human activities are now threatening to exceed thresholds for central Earth System processes, potentially moving the Earth System out of the Holocene state. To avoid such consequences, the concept of Planetary Boundaries was defined in 2009, and updated in 2015, for a number of processes which are essential for maint...

Much political and scientific focus has been on climate change in recent years. What is really unique about climate change, however, is that it has reminded us that there are limits to how much environmental change humans can induce without undermining the basis of our existence and triggered an understanding that local and regional environmental m...

1. Phytoplankton assemblages in the open ocean are usually assumed to be mixed on local scales unless large semi-permanent density discontinuities separating water masses are present. Recent modelling studies have, however, suggested that ephemeral submesoscale oceanographic features leading to only subtle density discontinuities may be important f...

Picoplankton are an ecologically important component of pelagic Arctic marine ecosystems that may be heavily impacted by climate change. In order to assess potential impacts of a changing environment on this group, it is necessary to develop a better understanding of their population dynamics and seasonal distribution. This study, carried out in Di...

Appreciation of the fact that our planet functions as a system, i.e., the Earth System (ES), defined as “the interacting physical, chemical and biological global-scale cycles (often called biogeochemical cycles) and energy fluxes which provide the conditions necessary for life on this planet” (Oldfield F, Steffen W, The earth system. In: Steffen W,...

2 Abstract Estimates of carbon flux to the deep oceans are essential for our understanding for global carbon budgets. We identify an important mechanism, the lipid pump, that has been unrecorded in previous estimates. The seasonal lipid pump is highly efficient in sequestering carbon in the deep ocean. It involves the vertical transport and respira...

Jaramillo and Destouni claim that freshwater consumption is beyond the planetary boundary, based on high estimates of water cycle components, different definitions of water consumption, and extrapolation from a single case study. The difference from our analysis, based on mainstream assessments of global water consumption, highlights the need for c...