Atmospheric carbon last year reached levels not seen in 800,000 years

The concentration of carbon dioxide (CO2) in Earth’s atmosphere reached 405 parts per million (ppm) last year, a level not seen in 800,000 years, according to a new report. It was also the hottest year on record that did not feature the global weather pattern known as El Niño, which is driven by warmer than usual ocean waters in the Pacific Ocean, concludes the State of the Climate in 2017, the 28th edition of an annual compilation published by the National Oceanic and Atmospheric Administration (NOAA). Overall, 2017 ranked as the second or third warmest year, depending on which measure is used, since researchers began keeping robust records in the mid-1800s.

Even if humanity “stopped the greenhouse gasses at their current concentrations today, the atmosphere would still continue to warm for next couple decades to maybe a century,” said Greg Johnson, an oceanographer at NOAA’s Pacific Marine Environmental Laboratory in Seattle, Washington, during a press call yesterday about the report.

The hefty document includes data compiled by 524 scientists working in 65 countries. A few highlights:
  • Atmospheric concentrations of CO2—the primary planetary warming gas—last year rose by 2.2 ppm over 2016. Similar levels were last reached at least 800,000 years ago, according to data obtained from air bubbles trapped in ancient ice cores.
  • Atmospheric concentrations of methane and nitrous oxide—both potent warming gases—were the highest on record. Levels of methane increased in 2017 by 6.9 parts per billion (ppb), to 1849.7 ppb, compared with 2016. Nitrous oxide levels increased by 0.9 ppb, to 329.8 ppb.
  • Last year also marked the end of a world-wide coral bleaching event that lasted 3 years. Coral bleaching occurs when seawater warms, causing corals to release algae living within their tissues, turning the coral white and sometimes resulting in the death of the coral. It was the longest documented bleaching event.
  • Global precipitation in 2017 was above the long-term average. Russia had its second wettest year since 1900. Parts of Venezuela, Nigeria, and India also experienced heavier than usual rainfall and flooding.
  • Warmer temperatures contributed to wildfire outbreaks around the world. The United States suffered an extreme wildfire season that burned 4 million hectares and caused more than $18 billion in damages. The Amazon region experienced some 272,000 wildfires.
  • In Alaska, record high permafrost temperatures were reported at five of six permafrost observatories. When thawed, permafrost releases CO2 and methane into the atmosphere and can contribute to global warming.
  • Arctic sea ice took a hit. The extent of sea ice hit a 38-year low, and was 8% below the mean extent reported for 1981 to 2010. Spring snow cover in the Arctic, however, was greater than the 1981 to 2010 average, and the Greenland Ice Sheet recovered from a record low mass reported in 2016. 2017 was also the second warmest year on record for the Arctic.
  • Many countries reported setting high-temperature records, including Argentina, Uruguay, Spain, Bulgaria, and Mexico.

Are Emperor Penguins Eating Enough?


Scienceadaily.com - For Emperor penguins waddling around a warming Antarctic, diminishing sea ice means less fish to eat. How the diets of these tuxedoed birds will hold up in the face of climate change is a big question scientists are grappling with.

Researchers at the Woods Hole Oceanographic Institution (WHOI) have developed a way to help determine the foraging success of Emperor penguins by using time-lapse video observations relayed to scientists thousands of miles away. The new remote sensing method is described in the May 2, 2018, issue of the Journal of Applied Physics.

"Global warming may be cutting in on food availability for Emperor penguins," said Dan Zitterbart, a scientist at WHOI and co-author of the study. "And if their diets change significantly, it could have implications on the health and longevity of these animals -- which are already expected to be highly threatened or close to extinct by the end of this century. With this new approach, we now have a logistically viable way to determine the foraging success of these animals by taking images of their behavior once they return back to the colony from their foraging trips."

Off all the penguin species, Emperor penguins tend to be the biggest eaters. And for good reason: they make exceptionally long treks on sea ice to reach their foraging grounds -- sometimes up to 75 miles during the winter -- and feed their large chicks when they return. But as sea ice diminishes, so does the microscopic plankton living underneath, which serves as the primary food source for fish that penguins eat. Sea ice also provides an important resting platform for the penguins in between foraging dives, so melting can make foraging that much harder.

Determining the species' foraging success involves a two-step process. First, digital photos of the birds are taken every minute throughout the day using an inexpensive time-lapse camera perched above the colony 100 feet away. The camera is rugged enough to withstand up to ?50° Celsius temperatures and wind speeds above 150 kilometers per hour.

Céline Le Bohec, a research scientist in ecology from the Centre national de la recherche scientifique (CNRS) and the Centre Scientifique de Monaco, and co-author of the study, says this spying capability overcomes a major limitation in Antarctic field research: the ability to monitor conditions remotely.

"It's really important to be able to understand how changing environmental conditions will impact penguin populations, but the harsh weather conditions and logistic difficulties linked to the remoteness of the white continent have made it very challenging to get information from over there," she said. "Now, with our observatories, especially remotely-controlled ones, we can go online anytime and instantly see what is happening in the colony.

Moreover, due to their position at the upper level of the food web, working on top-predators such as Emperor penguins, is very useful for understanding and predicting the impact of global changes on the polar marine biome: it's like having an alarm system on the health of these ecosystems."

Images are recorded and stored in an image database and later correlated with sensor-based measurements of air temperature, relative humidity, solar radiation, and wind. The combined data sets enable Zitterbart and his team to calculate a "perceived penguin temperature" -- the temperature that penguins are feeling. It is much like the wind chill factor for humans: the air temperature may be -12° Celsius, but other factors can make it feel colder.

"Early in the project, we thought if, for example, the wind was blowing faster than 15 meters per second, the penguins would always be huddling, regardless of the other environmental conditions," said Sebastian Richter, a Ph.D. student in Zitterbart's group and lead author of the study. "However, we did not find this to be true, and soon realized that we needed to account for the other weather conditions when assessing huddling behavior."

By correlating the penguin's "wind chill" temperature with video observations of when the penguins begin huddling, they're able to come up with a "transition temperature" -- the temperature at which colonies shift from a scattered, liquid-like state to a huddled, solid-like state. If the transition occurs at warmer temperatures, it means the penguins are feeling cold earlier and begin huddling to stay warm and conserve energy. And that indicates that the penguins had less body fat upon their return from foraging and were probably undernourished because they did not find enough food to eat within a reasonable distance from their breeding colony. If the transition temperature is lower later in the season, it suggests that the foraging season was a success and the animals returned well-fed and with higher amounts of body fat.

Zitterbart says the information may ultimately be used to derive conservation measures to protect Emperor penguins. According to a previous WHOI study, the species is critically endangered, and it's projected that by 2100, the global population will have declined by 20% and some colonies might reduce by as much as 70% of the current number of breeding pairs of Emperor penguins if heat-trapping gas emissions continue to rise and Antarctic sea ice continues to retreat.

"With the information produced by our observatories, population modelling will help us to better project the fate of the different colonies that are left," he said. "It's important to know which colonies are going to be the first most affected by climate change, so if it appears that a certain colony will remain strong over the next century, conservation measures like marine protected areas can be established to better protect them."



Source : Woods Hole Oceanographic Institution

Third of early deaths could be prevented by everyone giving up meat, Harvard says

At least one-third of early deaths could be prevented if everyone moved to a vegetarian diet, Harvard scientists have calculated.

Dr Walter Willett, professor of epidemiology and nutrition at Harvard Medical School said the benefits of a plant-based diet had been vastly underestimated.

Recent figures from the Office for National Statistics suggested that around 24 per cent or 141,000 deaths each year in Britain were preventable,  but most of that was due to smoking, alcohol or obesity.

But the new figures from Harvard suggest that at least 200,000 lives could be saved each year if people cut meat from their diets.


Speaking at the Unite to Cure Fourth International Vatican Conference in Vatican City, Dr Willett, professor of epidemiology and nutrition at Harvard Medical School said: “We have just been doing some calculations looking at the question of how much could we reduce mortality shifting towards a healthy, more plant based diet, not necessarily totally vegan, and our estimates are about one third of deaths could be prevented.

“That’s not even talking about physical activity or not smoking, and that’s all deaths, not just cancer deaths. That’s probably an underestimate as well as that doesn’t take into account the fact that obesity is important and we control for obesity.

“When we start to look at it we see that healthy diet is related to a lower risk of almost everything that we look at. Perhaps not too surprising because everything in the body is connected by the same underlying processes.”

British-born Professor David Jenkins, of the University of Toronto, who is credited with developing the glycemic index which explains how carbohydrates impact blood sugar, also told the conference that the benefits of vegetarianism had been ‘undersold.’

Dr Jenkins said humans would do better following a "simian" diet, similar to lowland gorillas who eat stems, leaves, vines and fruits rather than a "paleo" or caveman diet, which cuts carbohydrates but allows meat.

His team recently teamed up with The Bronx Zoo in New York and travelled to central Africa to record the feeding habits of gorillas.

When they recreated the diet for humans - which amounted to 63 servings of fruit and vegetables a day - they found a 35 per cent fall in cholesterol, in just two weeks, the equivalent of taking statins.

“That was quite dramatic,” he said “We showed that there was no real difference between what we got with the diet and what we got with a statin.”

Around 17.5 million people eligible for statins to stave off heart disease, equating to most men over 60 and most women over 65. But many complain of side effects and stop taking the drugs.

Dr Jenkins added: “We’re saying you’ve got a choice, you can change your diet to therapeutically meaningful change or you can take a statin. Drug or diet.”

Dr Neal Barnard, president of the Committee for Responsible Medicine also said people need to wake up to the health benefits of vegetarianism and veganism.

“I think we’re underestimating the effect,” he told delegates. “I think people imagine that a healthy diet has only a modest effect and a vegetarian diet might help you lose a little bit of weight. But when these diets are properly constructed I think they are enormously powerful.

“A low-fat vegan diet is better than any other diet I have ever seen for improving diabetes.

“With regards to inflammatory diseases like rheumatoid arthritis we are seeing tremendous potential there too. Partly because of things we are avoiding and cholesterol but also because of the magical things that are in vegetables and fruits which just aren’t in spam.”

Source : Telegraph.co.uk