Long-term consequences of CO2 emissions
Oxygen in the ocean will continue to decrease for many centuries
2021-04-16
(Press-News.org) The life of almost all animals in the ocean depends on the availability of oxygen, which is dissolved as a gas in seawater. However, the ocean has been continuously losing oxygen for several decades. In the last 50 years, the loss of oxygen accumulates globally to about 2% of the total inventory (regionally sometimes significantly more). The main reason for this is global warming, which leads to a decrease in the solubility of gases and thus also of oxygen, as well as to a slowdown in the ocean circulation and vertical mixing. A new study published today in the scientific journal Nature Communications shows that this process will continue for centuries, even if all CO2 emissions and thus warming at the Earth's surface would be stopped immediately.
"In the study, a model of the Earth system was used to assess what would happen in the ocean in the long term if all CO2 emissions would be stopped immediately", explains the author, Professor Andreas Oschlies from GEOMAR Helmholtz Centre for Ocean Research Kiel. "The results show that even in this extreme scenario, the oxygen depletion will continue for centuries, more than quadrupling the oxygen loss we have seen to date in the ocean ", Oschlies continues.
The long-term decrease in oxygen takes place primarily in deeper layers. According to Prof. Oschlies, this also has an impact on marine ecosystems. A so-called 'metabolic index', which measures the maximum possible activity of oxygen-breathing organisms, shows a widespread decline by up to 25%, especially in the deep sea (below 2000 metres). This is likely to lead to major shifts in this habitat, which was previously considered to be very stable, explains the oceanographer. These changes have already been initiated by our historical CO2 emissions and are now on their way to the deep ocean. He recommends that a comprehensive investigation of the deep ocean habitat, which has only been studied randomly so far, should take place before this environment, that is deemed as having been stable for many millennia, is likely to change significantly due to the now expected decrease in oxygen.
In the upper layers of the ocean, the model shows a much faster response to climate action. There, a further expansion of the relatively near-surface oxygen minimum zones can be stopped within a few years if the emissions were stopped. An ambitious climate policy can therefore help to prevent at least the near-surface ecosystems from being put under further pressure by a progressive decrease in oxygen.
INFORMATION:
The study was inspired by discussions with members of the Collaborative Research Centre "Climate-Biogeochemical Interactions in the Tropical Ocean" (SFB 754) completed just over a year ago, and the Global Ocean Oxygen Network (GO2NE), and will be followed by more detailed investigations within the framework of the UN Decade of Ocean Sciences for Sustainable Development 2021-2030.
Contact:
Dr. Andreas Villwock (GEOMAR, Communication and Media), Tel.:+49 0431 600-2802, presse@geomar.de
[Attachments] See images for this press release:
ELSE PRESS RELEASES FROM THIS DATE:
2021-04-16
In a new publication from Opto-Electronic Advances; DOI https://doi.org/10.29026/oea.2021.200031, Researchers led by Professor Baohua Jia at Swinburne University of Technology, Victoria, Australia, Professor Cheng-Wei Qiu at National University of Singapore, Singapore and Professor Tian Lan at Beijing Institute of Technology, Beijing, China considered the generation of super-resolved optical needle and multifocal array using graphene oxide metalenses.
Ultrathin and lightweight, metalenses are becoming increasingly significant for their use in photonic chips, biosensors and micro imaging systems such as smart phone cameras.
Compared to conventional lenses, metalenses can improve the image quality of current cameras, ...
2021-04-16
In most living animals, egg cells are vastly larger than sperm cells. In humans, for example, a single egg is 10 million times the volume of a sperm cell.
In a new study, Northwestern University researchers found that competition and natural selection drove this curious size discrepancy.
Using mathematical modeling, the researchers considered a time very early in evolution when primordial species reproduced using external fertilization. In the model, bigger reproductive cells, or gametes, presented a competitive edge because they could hold more nutrients for a potential zygote. Smaller gametes, however, required fewer resources to make, which put less stress on the parent.
"Organisms either needed to produce the biggest gametes with the most provisions ...
2021-04-16
When temperatures drop below zero degrees Celsius, water turns to ice. But does everything actually freeze if you just cool it down enough? In the classical picture, matter inherently becomes solid at low temperatures. Quantum mechanics can, however, break this rule. Therefore, helium gas, for example, can become liquid at -270 degrees, but never solid under atmospheric pressure: There is no helium ice.
The same is true for the magnetic properties of materials: at sufficiently low temperatures, the magnetic moments known as 'spins', for example, arrange themselves in such a way that they are oriented opposite/antiparallel to their respective neighbors. One can think of this as arrows pointing alternating up and down along a chain or in a checkerboard pattern. It ...
2021-04-16
Snow cover in the Alps has been melting almost three days earlier per decade since the 1960s. This trend is temperature-related and cannot be compensated by heavier snowfall. By the end of the century, snow cover at 2,500 meters could disappear a month earlier than today, as simulations by environmental scientists at the University of Basel demonstrate.
Global warming demands huge adjustments in tourism, hydropower generation and agriculture in alpine areas. But the fauna and flora also have to adapt to rising temperatures. By the end of the century, ...
2021-04-16
If you are exposed to silica (quartz) dust at work - e.g. from working with concrete and granite - you have a greater risk of certain types of rheumatic disease. This is shown by results from Aarhus University and Aarhus University Hospital, which have just been published in the International Journal of Epidemiology.
Exposure to silica dust at work, which is the case especially at workplaces within construction and industry, may lead to autoimmune rheumatic diseases. Photo: Unsplash.
Exposure to silica dust at work, which is the case especially at workplaces within construction and industry, may lead to autoimmune rheumatic diseases. Photo: Unsplash.
As the research results from Aarhus University show, exposure to ...
2021-04-16
The leading newspapers in two nuclear waste management forerunner countries, Finland and France, fulfil their "watchdog" roles in highly distinct ways. The Finnish Helsingin Sanomat (HS) tends to reproduce government and industry framings, whereas Le Monde cherishes its role as an independent critic of the powers that be. These differences reflect distinct cultural, political and media traditions in the two countries.
"The critical watchdog model works in a liberal democracy such as the French, based on mistrust towards the governing elites. But would it backfire in Finland by undermining the very institutional trust that the Nordic democracies have been built upon throughout history?" asks the first author of the article, Research Fellow Markku Lehtonen from the Department of Humanities ...
2021-04-16
A new study has shown that underweight and overweight women are at a significantly higher risk of experiencing recurrent miscarriages compared to those of average weight.
A research team led by the University of Southampton assessed the link between women's lifestyle and risk of recurrent pregnancy loss, defined as women having two or more consecutive early miscarriages. The systematic review and meta-analysis study has been published in the journal Scientific Reports.
Miscarriage is the most common complication of early pregnancy, affecting 15 - 20% of all pregnancies. Recurrent pregnancy loss is a complex disease and although often attributed to numerous medical factors and lifestyle influences, the cause is deemed "unexplained" ...
2021-04-16
Tokyo, Japan - Leukemias are debilitating cancers of the hematopoietic or blood-forming cells of the bone marrow. Now, researchers at Tokyo Medical and Dental University (TMDU) describe an ingenious strategy against chronic myelomonocytic leukemia (CMML) wherein an antibody-drug conjugate (ADC) comprising a cytotoxic drug payload linked to an antibody that selectively targets specific cell lines effectively blocks malignant cell proliferation at source.
Hematopoietic stem and progenitor cells (HSPCs) continually differentiate into the entire panoply of blood cells, as many as 500 ...
2021-04-16
Since fast radio bursts (FRBs) were first discovered over a decade ago, scientists have puzzled over what could be generating these intense flashes of radio waves from outside of our galaxy. In a gradual process of elimination, the field of possible explanations has narrowed as new pieces of information are gathered about FRBs - how long they last, the frequencies of the radio waves detected, and so on.
Now, a team led by McGill University researchers and members of Canada's CHIME Fast Radio Burst collaboration has established that FRBs include radio waves at frequencies lower than ever detected before, a discovery that redraws the boundaries for theoretical astrophysicists trying to put their finger on the source of FRBs.
"We ...
2021-04-16
WHAT:
The experimental antiviral drug MK-4482 significantly decreased levels of virus and disease damage in the lungs of hamsters treated for SARS-CoV-2 infection, according to a new study from National Institutes of Health scientists. SARS-CoV-2 is the virus that causes COVID-19. MK-4482, delivered orally, is now in human clinical trials. Remdesivir, an antiviral drug already approved by the U.S. Food and Drug Administration for use against COVID-19, must be provided intravenously, making its use primarily limited to clinical settings.
In their study, published in the journal ...
LAST 30 PRESS RELEASES:
[Press-News.org] Long-term consequences of CO2 emissions
Oxygen in the ocean will continue to decrease for many centuries
