Saturday, November 26, 2022

Key to chemical industries’ sustainable future? The world’s first industrial model of a flow photo-on-demand synthesis system

Continuous production of useful chemical products using chloroform as a precursor

Peer-Reviewed Publication

KOBE UNIVERSITY

Figure 1. 

IMAGE: THE FLOW PHOTO-ON-DEMAND CHEMICAL SYNTHESIS SYSTEM DEVELOPED IN THIS STUDY view more 

CREDIT: AKIHIKO TSUDA

Various chemical products, such as polymers and pharmaceutical intermediates, are currently synthesized with phosgene as their precursor or raw material. However, phosgene is highly toxic and this usage poses safety risks. Thus, there is demand for the development of new methods and substitutes to replace phosgene. In collaboration with industry, Associate Professor TSUDA Akihiko’s research group at Kobe University Graduate School of Science has become the first in the world to successfully develop a new flow photo-on-demand synthesis system that uses chloroform as the precursor. Using this system, they were able to synthesize phosgene-derived chemical products. Furthermore they achieved a high conversion rate (over 96%), synthesizing these useful compounds in a short period of time (a minute or less of light exposure). The system has multiple advantages; it is safe, inexpensive and simple with a low impact on the environment. It can be used to synthesize various chemical products, which it can produce continuously in large quantities. The researchers expect that this system can be scaled up into a model system of industrial production in the near future.

Patents for this system were filed in Japan in February 2021 and internationally in January 2022. Following the patent announcement in August 2022, the related academic paper was published online in Organic Process Research & Development (OPR&D) on November 11, 2022.

Main Points

  • From the common organic solvent chloroform and commercially available alcohol, the researchers successfully synthesized pharmaceutical intermediates and polymers at a highly efficient rate (over 96%) and in a short amount of time (a minute or less of light exposure).
  • They showed that continuous production is possible, which cannot be done with conventional batch systems.
  • In 2 hours, they successfully synthesized up to ten grams of chemical products (and this can be scaled up)
  • They synthesized 10 types of functional carbonates and 3 types of polycarbonates as examples.
  • Improved safety compared to the standard method of producing phosgene (a strong exothermic reaction of carbon monoxide and chlorine gas that uses a carbon catalyst). The chloroform used as a precursor in the new method is easy to store safely and the chemical reaction can be controlled by exposure to light.
  • The byproduct of this new method is mostly hydrogen chloride (neutralized by alkali), therefore dirt does not build up inside the system apparatus. The reduced need to clean the inside lessens the environmental impact and lowers costs.
  • The system achieves continuous production without the additional use of organic solvents.
  • This new chemical reaction system is expected to make a significant contribution in the move towards carbon neutral and sustainable societies.

(a) A conventional reaction with phosgene, (b) the photo-on-demand phosgenation reaction developed at Kobe Univ., and (c) a batch-type reaction system for the photo-on-demand chemical synthesis developed at Kobe Univ.

System overview of the flow photo-on-demand chemical synthesis method developed in this study.

Research Background
Phosgene (COCl2) is used as precursor for polymers and as a pharmaceutical intermediate. The global phosgene market continues to grow by several percent each year, with around 8 to 9 million tonnes produced annually. However, phosgene is extremely toxic. For safety reasons, research and development is being conducted to find alternatives. In a world-first discovery, Associate Professor Tsuda’s research group irradiated chloroform with ultraviolet light, which caused it to react with oxygen and generate high yields of phosgene (patent no. 5900920). In order to do this in an even saferand easier manner, the research group found a way that the phosgene-generating reactions could be instantly performed. They first dissolved the reactants and catalysts in chloroform, and generated phosgene by irradiating the solution with light (patent no. 6057449). In this way, phosgene-based organic synthesis can be carried out as if phosgene wasn’t used.

The research group has named their discovery ‘photo on demand organic synthesis method’ and have successfully used it to synthesize numerous useful organic chemicals and polymers (list of patents (in Japanese): Patents of Tsuda Laboratory). For example, they successfully synthesized large quantities of chloroformate and carbonate in a safe, inexpensive and simple manner merely by irradiating a mixed solution of chloroform and alcohol (with a base added as needed) with light (Figure 2, for more information see press release (Japanese) and journal paper (English)).

These highly original reactions developed at Kobe University have been improved through cooperation with domestic chemical companies, and the eventual aim of this research is practical implementation. With the addition of funding from JST A-STEP, further applied research is being conducted, as well the development of functional polyurethane using this synthesis method.

The photo-on-demand organic synthesis method is highly safe and economical, in addition to having a low impact on the environment. Consequently, it has garnered attention from both industry and academia as a sustainable chemical synthesis method (Highlights of Tsuda Laboratory (in Japanese)).

Research Methodology
In this research, a flow photo-on-demand system was redesigned for the photo-oxidation reaction of chloroform. Through experimenting with various flow channel arrangements, materials and light sources, the following system was created as shown in Figures 1 and 3. In the batch photo-on-demand method developed by this research group previously, the photoreaction between the chloroform and oxygen occurs in heterogeneous phases where the chloroform is a liquid and the oxygen is a gas (Figure 2c). However, in experiments using the new system the authors found that the reaction dramatically increased when both were in a gaseous state. By irradiating this gaseous mixture of vaporized chloroform and oxygen under ultraviolet light, the majority (over 96%) was converted into phosgene. Furthermore, the phosgene continuously reacted with the alcohol inside the system (with a base catalyst added as required), which meant that the system could be used to continuously synthesize high yields of chloroformate, carbonates and polycarbonates on a gram scale (Figure 4). These reactions are completed inside the system so the highly toxic phosgene gas does not escape. N-methylimidazole (NMI), which becomes an ionic liquid when it reacts with hydrogen chloride, was used as the base catalyst, so carbonates could be synthesized without using additional solvents. This system can be scaled up further, which will enable it to be used in a wide range of fields from academia to chemical industries.

Mechanism: It is thought that the chloroform photo-oxidation reaction is promoted by a radical chain mechanism. The ultraviolet light cleaves the C-Cl bond, which produces chlorine radicals and these radicals become primers that instigate the mechanism.

The researchers confirmed that the chloroform photo-oxidation reaction is extremely energy efficient even when a low-power light source is used. This is due to the oxidation part of the reaction whereby chlorine radicals are repeatedly consumed and regenerated.

Further Developments
The photo-on-demand synthesis method is expected to spark new innovation in how various chemical products are synthesized with phosgene as a precursor. With this new flow photo-on-demand system, it is possible to avoid the dangers of directly using phosgene produced from carbon monoxide and chlorine because the phosgene reaction occurs within the closed environment inside the system. In addition, the system only uses chloroform and oxygen as precursors, meaning that expensive phosgene substitutes are not required. This safe and simple versatile system can be used for the small to large-scale synthesis of various chemical products and the apparatus of this basic model can be customized to suit specific chemical reactions. It is hoped that this system can be used for industrial production by refining the process according to the scale of production. However, this system is not only for large scale chemical production; it will also be of great benefit to chemical manufacturers who need to produce various products on a small to medium scale. It is hoped that it can be used in new ventures, as well as to replace existing set-ups that are wearing out.

Acknowledgements
This research was supported by the Adaptable and Seamless Technology Transfer Program through Target-driven R&D (A-STEP) (seeds development type) from the Japan Science and Technology Agency (JST). ‘Developing highly functional and high added value polyurethane-materials through safe production processes using fluoroalkyl carbonates as key intermediates’ (Principle Researcher: Akihiko Tsuda).

Patent Information
Presentation Title: Method for Producing Halogenated Carbonyls
Patent application no. : 2021-21001 (Date of application: February 12, 2021).
Priority application no.: PCT/JP2022/2661 (Date of application: January 25, 2022).
Patent publication no.: WO2022172744 A1 (Date of publication: August 18, 2022).
Presenters: Akihiko Tsuda, and 2 others.
Applicants: Kobe University, and 2 others.

Journal Information
Title:

“Flow Photo-on-Demand Phosgenation Reactions with Chloroform”
DOI: doi.org/10.1021/acs.oprd.2c00322
Authors:
Yue Liu, Itsuumi Okada, Akihiko Tsuda*
* Corresponding author
Kobe University Graduate School of Science
Journal:
Organic Process Research & Development (OPR&D)

Covid-19: the Spike protein is no longer the only target

A research team led by the UNIGE reveals a hidden cavity on a key SARS-CoV-2 protein to which drugs could bind

Peer-Reviewed Publication

UNIVERSITÉ DE GENÈVE

Covid-19: the Spike protein is no longer the only target 

IMAGE: POSSIBLE MECHANISM OF ACTION OF A DRUG TARGETING THE SARS-COV-2 NSP1. IN INFECTED CELLS, NSP1 BLOCKS THE RIBOSOME’S MRNA CHANNEL BY ACTING AS A «CORK» THAT PREVENTS THE EXPRESSION OF THE HOST’S MRNA. THE BINDING OF A LIGAND TO THE PROPOSED CRYPTIC POCKET HIGHLIGHTED IN PURPLE COULD PREVENT THE NSP1-MEDIATED BLOCKAGE AND, ULTIMATELY, RECOVER THE RIBOSOME’S ABILITY TO INITIATE THE MRNA TRANSLATION. view more 

CREDIT: © CREATIVE COMMONS

With the continuous emergence of new variants and the risk of new strains of the virus, the development of innovative therapies against SARS-CoV-2 remains a major public health challenge. Currently, the proteins that are on the surface of the virus and/or are involved in its replication are the preferred therapeutic targets, like the Spike protein targeted by vaccines. One of them, the non-structural protein Nsp1, had been little studied until now. A team from the University of Geneva (UNIGE), in collaboration with University College London (UCL) and the University of Barcelona, has now revealed the existence of a hidden ''pocket’ on its surface. A potential drug target, this cavity opens the way to the development of new treatments against Covid-19 and other coronaviruses. These results can be found in the journal eLife.


The fast rollout of new vaccines and antiviral drugs has helped to contain the Covid-19 pandemic, caused by the SARS-CoV-2 virus. Despite the progress made, the development of new therapies is still an urgent priority: the continuous emergence of new variants - some of which are resistant to current treatments - and the possible appearance of new strains of the virus represent a risk of new pandemics. Proteins are at the forefront of therapeutic targets to combat the virus. The best known is the Spike protein, which is located on the surface of SARS-CoV-2 and gives it its ‘‘spiky’’ appearance. It is the key to the virus entering our cells. It is the target of Messenger RNA vaccines.


A little-studied key protein

SARS-CoV-2 also makes other proteins - the «non-structural» proteins - using the resources of our cells after entering them. There are sixteen of them. They are essential for the replication of the virus. Some have been studied in the context of the development of new drugs. Others have received less attention. This is the case of the Nsp1 protein. Without obvious cavities on its surface to anchor a potential drug, researchers felt that it could not be a target for treatment.


‘‘Nsp1 is, however, an important infectious agent of SARS-CoV-2,’’ explains Francesco Luigi Gervasio, full professor at the Section of Pharmaceutical Sciences and the Institute of Pharmaceutical Sciences of Western Switzerland of the UNIGE Faculty of Science, and at the Department of Chemistry and the Institute of Structural and Molecular Biology at UCL. ‘‘This small viral protein selectively blocks ribosomes - the protein factories of our cells - making them unusable by our cells and thus preventing the immune response. At the same time, via ribosomes, Nsp1 stimulates the production of viral proteins.’’


Revealed by algorithms

Professor Gervasio’s team, in collaboration with UCL and the University of Barcelona, revealed the existence of a ‘‘hidden’’ cavity on the surface of Nsp1, which could be the target of future drugs against SARS-CoV-2. ‘‘To uncover this cryptic, partially hidden pocket, we carried out simulations using algorithms that we developed,’’ explains Alberto Borsatto, research and teaching assistant at the Section of Pharmaceutical Sciences and the Institute of Pharmaceutical Sciences of Western Switzerland of the Faculty of Sciences of the UNIGE, first author of the study. ‘‘Then, in order to confirm that this pocket could be used as a drug target, we used experimental screening and X-ray crystallography techniques.’’


The research team tested many small molecules that could potentially bind to the Nsp1 cavity (experimental screening). It identified one in particular  – 5 acetylaminoindane or 2E10 -  that also allowed the determination of the spatial arrangement of the atoms making up the cavity (by crystallography). These are essential data that form the basis for the development of new drugs.


‘‘These results pave the way for the development of new treatments targeting the Nsp1 protein, not only against SARS-CoV-2 and its variants but also against other coronaviruses in which Nsp1 is present,’’ says Francesco Luigi Gervasio, the study’s last author. As for the method developed to reveal the hidden pocket of Nsp1, it could be used to discover, on the surface of other proteins, new cavities still unknown to scientists.

Great potential for aquifer thermal energy storage systems

Low-temperature aquifer thermal energy storage systems enable climate-friendly heating and cooling – KIT study reveals potential for Germany

Peer-Reviewed Publication

KARLSRUHER INSTITUT FÜR TECHNOLOGIE (KIT)

Aquifer thermal energy storage systems 

IMAGE: COOLING IN SUMMER (LEFT) AND HEATING IN WINTER: AQUIFER THERMAL ENERGY STORAGE SYSTEMS, I.E. UNDERGROUND WATER-BEARING LAYERS, ARE SUITED FOR THIS PURPOSE. (GRAPHICS: RUBEN STEMMLE, AGW/KIT) view more 

CREDIT: RUBEN STEMMLE, AGW/KIT

Aquifer thermal energy storage systems can largely contribute to climate-friendly heating and cooling of buildings: Heated water is stored in the underground and pumped up, if needed. Researchers of Karlsruhe Institute of Technology (KIT) have now found that low-temperature aquifer thermal energy storage is of great potential in Germany. This potential is expected to grow in future due to climate change. The study includes the so far most detailed map of potential aquifer storage systems in Germany. The results are reported in Geothermal Energy. (DOI: 10.1186/s40517-022-00234-2

More than 30 percent of domestic energy consumption currently consumed in Germany is used for heating and cooling buildings. Decarbonization of this sector could therefore lead to major greenhouse gas emission reductions and largely contribute to climate protection. Aquifer thermal energy storage systems, i.e. water-bearing layers in the underground, are suited well for the seasonal storage and flexible use of heat and cold. Water has a high capacity of storing thermal energy. The surrounding rocks have an insulating effect. Underground aquifer thermal energy storage systems are accessed by boreholes and used to store heat from solarthermal plants or waste heat from industrial facilities. If required, the heat can be pumped up again. Such storage systems can be combined perfectly with heat networks and heat pumps. Near-surface low-temperature aquifer thermal energy storage systems (LT-ATES) have proved to be particularly efficient. As the water temperature is not much higher than the temperature of the environment, little heat is lost during storage.
 

More than Half of the German Territory Is Suited Well or Very Well

Researchers from KIT’s Institute of Applied Geosciences (AGW) and the Sustainable Geoenergy Junior Research Group have now identified the regions suited for low-temperature aquifer thermal energy storage in Germany. “Criteria for an efficient LT-ATES operation include favorable hydrogeological conditions, such as the productivity of groundwater resources and groundwater flow velocity,” Ruben Stemmle explains. The member of AGW’s Engineering Geology Group and first author of the study adds: “Moreover, energy consumption for heating and cooling must be balanced. It can be approximated by the ratio of heating and cooling degree days.”

Researchers have combined hydrogeological and climate criteria in a spatial analysis. They found that 54 percent of the German territory will be suited very well or well for LT-ATES in the upcoming decades. These potentials are largely concentrating on the North German Basin, the Upper Rhine Graben, and the South German Molasse Basin. The corresponding map was generated by the researchers with the help of a geoinformation system (GIS) and a multi-criteria decision analysis.
 

Climate Change Will Enhance the Potential of Aquifer Storage 

According to the study, the areas suited well or very well for LT-ATES will presumably increase by 13 percent for the period from 2071 to 2100. The large increase of very well-suited regions is attributed to an increasing cooling demand in the future, i.e. it will be due to climate change. However, use of aquifer storage systems is largely restricted in water protection zones, which will reduce the very well or well-suited areas by around eleven percent. “Still, our study reveals that Germany has a high potential for seasonal heat and cold storage in aquifers,” Stemmle says. (or)
 

Original Publication (Open Access)

Ruben Stemmle, Vanessa Hammer, Philipp Blum and Kathrin Menberg: Potential of low‑temperature aquifer thermal energy storage (LT‑ATES) in Germany. Geothermal Energy, 2022. DOI: 10.1186/s40517-022-00234-2 

https://geothermal-energy-journal.springeropen.com/articles/10.1186/s40517-022-00234-2
 

More about the KIT Energy Center: https://www.energie.kit.edu
 

Contact for this press release:

Dr. Martin Heidelberger, Press Officer, Phone: +49 721 608-41169, martin heidelberger∂kit edu
 

Being “The Research University in the Helmholtz Association”, KIT creates and imparts knowledge for the society and the environment. It is the objective to make significant contributions to the global challenges in the fields of energy, mobility, and information. For this, about 9,800 employees cooperate in a broad range of disciplines in natural sciences, engineering sciences, economics, and the humanities and social sciences. KIT prepares its 22,300 students for responsible tasks in society, industry, and science by offering research-based study programs. Innovation efforts at KIT build a bridge between important scientific findings and their application for the benefit of society, economic prosperity, and the preservation of our natural basis of life. KIT is one of the German universities of excellence.

This press release is available on the internet at http://www.kit.edu/kit/english/press_releases.php

High potentials for the use of low-temperature aquifer thermal energy storage (IMAGE)

KARLSRUHER INSTITUT FÜR TECHNOLOGIE (KIT)

Breaking nitrogen while generating methane

Insights into a “hot” microbe that can grow on nitrogen while producing methane

Peer-Reviewed Publication

MAX PLANCK INSTITUTE FOR MARINE MICROBIOLOGY

The cultures of microbes 

IMAGE: CLOSE VIEW OF METHANOTHERMOCOCCUS THERMOLITHOTROPHICUS CULTURE UNDER THE MICROSCOPE (LEFT) AND IN A CULTURE FLASK (MIDDLE AND RIGHT). THESE CELLS GROW ON NITROGEN GAS AS THE ONLY SOURCE OF NITROGEN. IF THERE IS NO NITROGEN GAS PRESENT, NOTHING GROWS (RIGHT). view more 

CREDIT: MAX PLANCK INSTITUTE FOR MARINE MICROBIOLOGY

Carbon and nitrogen are essential elements of life. Some organisms take up key positions for the cycling of both of them – among them Methanothermococcus thermolithotrophicus. Behind the complicated name hides a complicated microbe. M. thermolithotrophicus is a marine heat-loving methanogen. It lives in ocean sediments, from sandy coasts and salty marshes to the deep-sea, preferably at temperatures around 65 °C. It is able to turn nitrogen (N2) and carbon dioxide (CO2) into ammonia (NH3) and methane (CH4) by using hydrogen (H2). Both products, ammonia and methane, are very interesting for biotechnological applications in fertilizer and biofuels production.   

Tristan Wagner and Nevena Maslać from the Max Planck Institute for Marine Microbiology have now managed to grow this microbe in a fermenter – a challenging endeavour. “It is very complicated to provide the perfect conditions for this microbe to thrive while fixing N2 – high temperatures, no oxygen and keeping an eye on hydrogen and carbon dioxide levels”, says Maslać, who carried out the research as part of her PhD project. “But with some ingenuity and perseverance, we managed to make them thrive in our lab and reach the highest cell densities reported so far.” Once the cultures were up and running, the scientists were able to investigate the physiology of the microbe in detail, and later on deepen their study by looking how the metabolism from the microbe adapts to the N2-fixation. “In close collaboration with our colleagues Chandni Sidhu and Hanno Teeling, we combined physiological tests and differential transcriptomics, which allowed us to dig deeper into the metabolism of M. thermolithotrophicus”, Maslać explains.

As improbable as a bumblebee

The metabolic abilities of M. thermolithotrophicus are puzzling: These microbes use methanogenesis, a metabolism that originated on the early anoxic Earth, to acquire their cellular energy. Compared to humans that use oxygen to transform glucose into carbon dioxide, methanogens obtain only a very limited amount of energy from methanogenesis. Paradoxically, fixing nitrogen requires gigantic amounts of energy, which would exhaust them. “They are a bit like bumblebees, which are theoretically too heavy to fly but obviously do so, nevertheless”, says senior author Tristan Wagner, group leader of the Max Planck Research Group Microbial Metabolism. “Despite such energy limitation, these fascinating microbes have even been found to be the prime nitrogen fixers in some environments.”   

A robust nitrogenase

The enzyme that organisms use to fix nitrogen is called nitrogenase. Most common nitrogenases require Molybdenum to perform the reaction. Molybdenum nitrogenase is well-studied in bacteria living as symbionts in plant roots. Their nitrogenase can be inhibited by tungstate. Surprisingly, the Bremen scientists found that M. thermolithotrophicus is not disturbed by tungstate while growing on N2. “Our microbe was only dependent on molybdenum to fix N2 and not bothered by tungstate, which implies an adaptation of metal-acquisition systems, making it even more robust for different potential applications”, says Maslać.

Rethinking ammonia production

Nitrogen fixation, i.e., gaining nitrogen from N2, is the major process to insert nitrogen into the biological cycle. For industrial fertilizer production this process is carried out via the Haber-Bosch process, which artificially fixes nitrogen to produce ammonia with hydrogen under high temperatures and pressures. It is used to produce most of the world’s ammonia, an essential fertilizer to sustain global agriculture. The Haber-Bosch process is extremely energy-demanding: It consumes 2% of the world’s energy output, and releasing at the same time up to 1.4% of global carbon emissions. Thus, people are looking for more sustainable alternatives to produce ammonia. “The process used by M. thermolithotrophicus shows that out there in the microbial world there are still solutions that might allow for a more efficient production of ammonia, and that they can even be combined with biofuel production through methane”, says Wagner. “With this study, we understood that under N2-fixing conditions, the methanogen sacrifices its production of proteins to favor nitrogen capture, a particularly smart strategy of energy reallocation”, Wagner sums up. “Our next step will be to move into the molecular details of the process and the enzymes involved, as well as to look into other parts of the organism’s metabolism.”

Three days to help save our coastal habitats

A global gathering of marine scientists has set a three-day symposium to work out how we can maximise the many life and planet protecting services we as humans benefit from our coastal habitats

Meeting Announcement

UNIVERSITY OF PORTSMOUTH

A global gathering of marine scientists has set a three-day symposium to work out how we can maximise the many life and planet protecting services we as humans benefit from our coastal habitats.  

The loss of biodiversity and effects of climate change are impacting the health of the whole planet. Climate change, pollution, overfishing and shipping are just some of the issues that have led to a worrying decline in the health of the seas that surround us. 

On 22 November scientists will gather at an especially convened meeting in London, brought together by the University of Portsmouth and Zoological Society London to take a new seascape approach to restoring our coastal resources and habitats. 

For the first two days the experts working in restoration and research from different coastal habitats will share knowledge and expertise and to create a holistic picture of the situation, joining the dots between shared challenges and novel research findings. On the third day scientists will bring together the evidence for how habitats are connected and what benefits this brings to solving the biodiversity and climate crisis. Their findings and possible solutions will be published in an open access paper. 

Conference organiser, Dr Joanne Preston from the School of Biological Science at the University of Portsmouth, says:  “The aim is to supercharge coastal restoration across temperate regions. By bringing together these experts we hope to move current conversations away from single species restoration. By taking a systems level approach that considers all the interactions and feedbacks that occur between healthy coastal habitats, we can move towards a seascape approach to nature restoration.

“For total habitat restoration we need to work collaboratively and think about the whole system as one seascape. Only then, can we start to understand more about the connectivity between different habitats and species such as saltmarsh, oysters, seagrass and kelp – all of which are in critical decline, and find ways to restore the entire system rather than single entities.”

The event will bring experts together to unlock the evidence needed to drive a joined-up approach to habitat restoration. This is important because in marine environments everything is connected by the 3-dimensional body of seawater. The connectivity of these habitats is vital for restoring food webs and repairing degraded and fragmented individual habits.

Coastal environments have been badly damaged with nearly all oyster reefs destroyed and over half the seagrass and saltmarsh beds gone. Experts hope that by trying to understand how each environment is connected they can plan to improve resilience. As well as individual habitats recovering there will be a knock-on benefit to the entire seascape - such as increasing fish populations, nitrate removal, biodiversity, carbon drawdown, and a decrease in erosion.

The Symposium is being held in person at the Zoological Society London on 22-24 November 2022. 

More details can be found here.  


Satellites cast critical eye on coastal 

dead zones

Peer-Reviewed Publication

MICHIGAN STATE UNIVERSITY

Algae blooms begin hypoxia cycle 

IMAGE: ALGAE BLOOM ON A CHINESE BEACH IS REPRESENTATIVE OF THE EXPANSIVE ALGAE BLOOMS WHICH ULTIMATELY LEACH OXYGEN FROM THE WATER, CREATING DEAD ZONES. view more 

CREDIT: RUISHAN CHEN, MICHIGAN STATE UNIVERSITY

A dead zone in the ocean is as bad as it sounds. Being clueless about dead zones scope and path is worse. Scientists at Michigan State University (MSU) have discovered a birds-eye method to predict where, when and how long dead zones persist across large coastal regions.

“Understanding where these dead zones are and how they may change over time is the first crucial step to mitigating these critical problems. But it is not easy by using traditional methods, especially for large-scale monitoring efforts,” said Yingjie Li, who did the work while a PhD student at MSU’s Center for System Integration and Sustainability (CSIS). He currently is a postdoctoral researcher at Stanford University.Dead zones – technically known as hypoxia -- are water bodies degraded to the point where aquatic life cannot survive because of low oxygen levels. They’re a problem mainly in coastal areas where fertilizer runoff feeds algae blooms, which then die, sink to the water’s bottom and decay. That decay eats up oxygen dissolved in the water, suffocating living life, such as fish and other organisms that make up vibrant living waters.

Dead zones can be hard to identify and track and usually have been observed by water samples. But as reported in Remote Sensing of the Environment, scientists have figure out a novel way to use satellite views to understand what’s happening deep below the ocean’s surface. They used the Gulf of Mexico at the mouth of the Mississippi River as a demonstration site.

The group supplemented data from water sampling with different ways to use satellite views over time. In addition to predicting the size of hypoxic zones, the study provides additional information on where, when, and how long hypoxic zones persist with greater details and enables modeling hypoxic zones at near-real-time.

Since 1995, at least 500 coastal dead zones have been reported near coasts covering a combined area larger than the United Kingdom, endangering fisheries, recreation and the overall health of the seas. Climate change is likely to exacerbate hypoxia.

The group notes the need to initiate a global coast observatory network to synthesize and share data for better understanding, predicting and communicating the changing coasts. Currently, such data is difficulty to come by. And the stakes are higher as fertilizer applied in a field can become run off in one part of a body of water miles away. The group points out the telecoupling framework, which enables understanding human and natural interactions near and far, would be useful to see the big picture of a problem.

“Damages to our coastal waters are a telecoupling problem that spans far beyond the dead zones – distant places that apply excessive fertilizers for food production and even more distant places that demand food. Thus, it’s critical we take a holistic view while employing new methods to gain a true understanding,” said Jianguo “Jack” Liu, MSU Rachel Carson Chair in Sustainability and CSIS director.

Besides, Li and Liu, “Satellite prediction of coastal hypoxia in the northern Gulf of Mexico” was written by Drs. Samuel Robinson and Lan Nguyen from the University of Calgary. The work was funded by the National Science Foundation and the Environmental Science and Policy Summer Research Fellowship.

This map shows hypoxia recurrence measured by the percentage of time with hypoxia detected during the summertime in 2014.


CREDIT

Michigan State University Center for Systems Integration and Sustainability.