Category Archives: Nature

Atlantic carbon dioxide doubles in a decade


And the consequences may be severe.

Increases in anthropogenic CO2 in the Atlantic Ocean between 2003 and 2014.

Increases in anthropogenic CO2 in the Atlantic Ocean between 2003 and 2014.

From the University of Miami, Rosenstiel School of Marine and Atmospheric Science:

A University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science-led study shows that the North Atlantic absorbed 50 percent more man-made carbon dioxide over the last decade, compared to the previous decade. The findings show the impact that the burning of fossil fuels have had on the world’s oceans in just 10 years.

To determine the total uptake and storage of carbon dioxide in the North Atlantic over the last several decades, researchers analyzed data collected from the same locations, but 10 years apart, to identify changes caused by man-made CO2. The data were collected during two National Science Foundation-funded international ship-based studies, CLIVAR (Climate Variability CO2 Repeat Hydrography) and GO-SHIP (Global Ocean Ship-Based Hydrographic Investigations Program).

“This study shows the large impact all of us are having on the environment and that our use of fossil fuels isn’t only causing the climate to change, but also affects the oceans by decreasing the pH,” said Ryan Woosley, a researcher in the UM Rosenstiel School, Department of Ocean Sciences.

The oceans help to slow the growth of human produced CO2 in the atmosphere by absorbing and storing about a quarter of the total carbon dioxide emissions. The North Atlantic is an area of high uptake and storage due to large-scale ocean circulations.

The uptake of CO2 has many impacts on ocean-dwelling organisms by decreasing the pH. The findings have important implications for marine organisms, such as corals and mollusks, which require a certain pH level in the surrounding water to build their calcium carbonate-based shells and exoskeletons.

The researchers hope to return in another 10 years to determine if the increase in carbon uptake continues, or if, as many fear, it will decrease as a result of slowing thermohaline circulation.

The study, titled “Rapid Anthropogenic Changes in CO2 and pH in the Atlantic Ocean: 2003-2014″ was published in the journal Global Biogeochemical Cycles. The study’s authors include: Woosley and Frank J. Millero of the UM Rosenstiel School; and Rik Wanninkhof of NOAA’s Atlantic Oceanographic and Meteorological Laboratory. The study was funded by the National Science Foundation through grant #OCE0752972. The study can be acce$$ed at http://onlinelibrary.wiley.com/doi/10.1002/2015GB005248/pdf

Headline of the day II: And one that’s unique?


And it’s from Science, that most austere of journals:

Ancient arachnid erection enshrined in amber

Nearly 99 million years ago, two harvestmen—known to some as daddy longlegs—decided to have sex. Little did they know that their final act would still be preserved today, enshrined in amber in striking detail.

And along the same line, a Guardian video, one of a series on Britain’s National Health Service, featuring a physician with a tale from the emergency room:

A&E confessions: a 90-year-old’s secret to a happy marriage

Program notes:

When a sweet, rosy-cheeked 90-year-old woman walked into her accident and emergency ward, the last thing Dr Sarah Johnston expected was some searingly honest and intimate advice on the secret to a lifelong happy marriage.

Map of the day: Forests lead to drinking water


From Effects of Drought on Forests and Rangelands in the United States: A Comprehensive Science Synthesis [PDF], a new report from the U.S. Forest Service, a map revealing the critical importance of forest as sources of providing drinking water supplies in the U.S.:

Index of forest importance [FIMP] to surface drinking water; higher values [shown in shades of blue] indicate greater importance

Index of forest importance [FIMP] to surface drinking water; higher values [shown in shades of blue] indicate greater importance

And some good news for the enviornment


A Canadian rainforest is saved.

From the BBC:

Indigenous tribes, timber firms and environmental groups in western Canada have welcomed a deal to protect one of the world’s largest remaining tracts of temperate rainforest.

The Great Bear Rainforest on the Pacific coast of British Columbia is home to many animals and ancient trees.

Logging will be banned across a huge area of the forest.

Environmental campaigners say the deal is a model for resolving similar land-use disputes around the world.

View from the heavens: Utah’s Great Salt Lake


From NASA’s Earth Observatory, an astronaut’s photo looking down at Utah [click on the image to enlarge, and go to the link for an even larger image]:

Astronaut photograph ISS043-E-123891 was acquired on April 4, 2015, with a Nikon D4 digital camera using a 170 millimeter lens, and is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. The image was taken by a member of the Expedition 43 crew. The image has been cropped and enhanced to improve contrast, and lens artifacts have been removed. The International Space Station Program supports the laboratory as part of the ISS National Lab to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. Caption by M. Justin Wilkinson, Texas State U., Jacobs Contract at NASA-JSC.

Astronaut photograph ISS043-E-123891 was acquired on April 4, 2015, with a Nikon D4 digital camera using a 170 millimeter lens, and is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. The image was taken by a member of the Expedition 43 crew. The image has been cropped and enhanced to improve contrast, and lens artifacts have been removed. The International Space Station Program supports the laboratory as part of the ISS National Lab to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. Caption by M. Justin Wilkinson, Texas State U., Jacobs Contract at NASA-JSC.

Deforestation linked to Zika virus spread


And it should come as no surprise, given that destruction of African forests has been linked to emergence of the deadly Ebola virus

From The Independent:

Environmental destruction both caused the horrific Zika virus to infect humans and is fuelling its explosive spread through the Americas, experts believe. Felling forests brought people into contact with it, and the growth of cities and even an increase in rubbish are factors behind its rapid proliferation.

>snip<

Professor Amy Vittor, an expert in insect-borne diseases at the Emerging Pathogens Institute of the University of Florida, said the emergence and spread of the virus was “absolutely” likely to be connected with environmental degradation “in its broadest sense”. She said that such diseases persisted in a “closed cycle of animals and mosquitoes” until they spread to people through such incursions as cutting down trees, adding that her research has shown that “deforestation followed by agriculture and regrowth of low-lying vegetation provided a much more suitable environment” for the insects than undisturbed, pristine forest.

And Dr Allison Gottwalt of the George Washington University’s Department of Epidemiology and Biostatistics describes felling forests as creating “ideal conditions for vectors to breed and spread infectious diseases”.

Gut feelings: Intestinal microbes and the brain


Torturers were long aware that our digestive track is loaded with nerves, and I recall talking to one American solider captured by the Germans during World War II who was subjected to ice water enemas in order to get him to talk. He said he’d never experienced anything so painful before or since, including burns.

Beyond the direct link the SS torturers employed, there’s another, more subtle link between gut and brain, namely the role the microbes harbor in our viscera play in shaping emotions, extroversion and introversion, and, quite possibly, the development of addictions, obsessive behaviors, and even autism and Parkinson’s disease.

From a 5 September 2013 New York Times report:

The trillions of bacteria that live in the gut — helping digest foods, making some vitamins, making amino acids — may help determine if a person is fat or thin.

The evidence is from a novel experiment involving mice and humans that is part of a growing fascination with gut bacteria and their role in health and diseases like irritable bowel syndrome and Crohn’s disease. In this case, the focus was on obesity. Researchers found pairs of human twins in which one was obese and the other lean. They transferred gut bacteria from these twins into mice and watched what happened. The mice with bacteria from fat twins grew fat; those that got bacteria from lean twins stayed lean.

The study, published online Thursday by the journal Science, is “pretty striking,” said Dr. Jeffrey S. Flier, an obesity researcher and the dean of the Harvard Medical School, who was not involved with the study. “It’s a very powerful set of experiments.”

The enteric nervous system harbors more neurons than the spinal cord, and is constantly signalling the brain.

And, it turns out, the nature of those signals is shaped by the billions of critters that dwell within us, the microbes that play vital roles in the digestion of out food.

And, it turns out, they may also make us happy or sad.

Consider the following from a 23 June 2015 New York Times report:

Since 2007, when scientists announced plans for a Human Microbiome Project to catalog the micro-organisms living in our body, the profound appreciation for the influence of such organisms has grown rapidly with each passing year. Bacteria in the gut produce vitamins and break down our food; their presence or absence has been linked to obesity, inflammatory bowel disease and the toxic side effects of prescription drugs. Biologists now believe that much of what makes us human depends on microbial activity. The two million unique bacterial genes found in each human microbiome can make the 23,000 genes in our cells seem paltry, almost negligible, by comparison. ‘‘It has enormous implications for the sense of self,’’ Tom Insel, the director of the National Institute of Mental Health, told me. ‘‘We are, at least from the standpoint of DNA, more microbial than human. That’s a phenomenal insight and one that we have to take seriously when we think about human development.’’

Given the extent to which bacteria are now understood to influence human physiology, it is hardly surprising that scientists have turned their attention to how bacteria might affect the brain. Micro-organisms in our gut secrete a profound number of chemicals, and researchers like Lyte have found that among those chemicals are the same substances used by our neurons to communicate and regulate mood, like dopamine, serotonin and gamma-aminobutyric acid (GABA). These, in turn, appear to play a function in intestinal disorders, which coincide with high levels of major depression and anxiety. Last year, for example, a group in Norway examined feces from 55 people and found certain bacteria were more likely to be associated with depressive patients.

So critical is the nervous system in our guts that many scientists now call it our “second brain.”

From a 12 February 2010 Scientific American report

“The system is way too complicated to have evolved only to make sure things move out of your colon,” says Emeran Mayer, professor of physiology, psychiatry and biobehavioral sciences at the David Geffen School of Medicine at the University of California, Los Angeles (U.C.L.A.). For example, scientists were shocked to learn that about 90 percent of the fibers in the primary visceral nerve, the vagus, carry information from the gut to the brain and not the other way around. “Some of that info is decidedly unpleasant,” Gershon says.

The second brain informs our state of mind in other more obscure ways, as well. “A big part of our emotions are probably influenced by the nerves in our gut,” Mayer says. Butterflies in the stomach—signaling in the gut as part of our physiological stress response, Gershon says—is but one example. Although gastrointestinal (GI) turmoil can sour one’s moods, everyday emotional well-being may rely on messages from the brain below to the brain above. For example, electrical stimulation of the vagus nerve—a useful treatment for depression—may mimic these signals, Gershon says.

Given the two brains’ commonalities, other depression treatments that target the mind can unintentionally impact the gut. The enteric nervous system uses more than 30 neurotransmitters, just like the brain, and in fact 95 percent of the body’s serotonin is found in the bowels. Because antidepressant medications called selective serotonin reuptake inhibitors (SSRIs) increase serotonin levels, it’s little wonder that meds meant to cause chemical changes in the mind often provoke GI issues as a side effect. Irritable bowel syndrome—which afflicts more than two million Americans—also arises in part from too much serotonin in our entrails, and could perhaps be regarded as a “mental illness” of the second brain.

And with that by way of preface, here’s a talk given by Dr. Emeran at UC San Francisco Medical School in December and just posted to the Web by University of California Television [and yes, it’s a bit on the technical side, but there’s enough there that’s accessible to a lay viewer that we though it worthwhile to post]:

The Microbiome Mind and Brain Interactions

Program notes:

Dr. Emeran Mayer, an expert on the clinical and neurobiological aspects of the gut-brain axis, is a Professor in the Department of Medicine, Physiology and Psychiatry at the David Geffen School of Medicine at UCLA. He is also the Executive Director of the Oppenheimer Family Center for Neurobiology of Stress, and Co-director of the CURE: Digestive Diseases Research Center. Recorded on 12/10/2015.