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Something peculiar is happening in the azure waters off the rocky cliffs of Ischia, Italy. There, streams of gas-filled volcanic bubbles rising up to the surface are radically changing life around them by making seawater acidic. Stanford researchers studying species living near these gassy vents have learned what it takes to survive in acidic waters, providing a glimpse of what future oceans might look like as they grow more acidic.

Volcanic carbon dioxide seeps from the ocean floor near Ischia, Italy [Credit: Pasquale Vassallo, Stazione Zoologica Anton Dohrn]

Their findings, published in Nature Communications, suggest that ocean acidification driven by human-caused carbon dioxide emissions could have a larger impact than previously thought.

"When an organism's environment becomes more acidic, it can dramatically impact not only that species, but the overall ecosystem's resilience, function and stability," said Stanford marine biologist Fiorenza Micheli, lead author on the paper. "These transformations ultimately impact people, especially our food chains."

A natural laboratory

Most ocean acidification studies to date have taken place in laboratories, making it impossible to assess how whole ecosystems comprised of multiple, interacting species would be affected. The real-life laboratory provided researchers an opportunity to examine dozens of species, from sea urchins to marine snails, that live in areas of different acidity along Ischia's volcanic carbon dioxide vents. In addition to studying how species diversity changed with acidification, they analyzed species traits, such as diet and growth, that influence how well the ecosystem performs. For example, sea snails were smaller in more acidic water, as their shells take longer to grow and are thinner and more brittle. These harmful effects on sea snails, a key food for animals higher up in the food chain, may affect fish populations.

Overall, the researchers found that the active venting zones with the most acidic waters were home to not only the least number of species, but also the lowest amounts of "functional diversity" – the range of ecosystem-support services or roles that each species can provide.

"Studying the natural carbon dioxide vents in Ischia allowed us to unravel which traits from different species, like snail shell strength, were more vulnerable to ocean acidification. These results illuminate how oceans will function under different acidification scenarios in the future," said lead author Nuria Teixidó, a marine biologist from Stazione Zoologica Anton Dohrn in Italy, who was a visiting researcher at Stanford during the research.

Acidification in the waters of Ischia displaced long-lived species, such as corals, that form habitat for other species – a process already often witnessed on reefs across the world. The researchers also found that high levels of carbon dioxide and more acidity favored species with short life spans and fast turnover as they are the only species that can resist these environmental conditions. This change could lead to further diversity loss and instability in the oceans, as biodiversity tends to increase an ecosystem's stability.

Biodiversity loss is mapped along a natural CO2 gradient [Credit: Nuria Teixidó, Stazione Zoologica Anton Dohrn]

A broader application

Localized case studies such as Ischia can shed light on how future global environmental conditions may affect ocean life. Beyond losing biodiversity, ocean acidification will threaten food security for millions of people who depend on seafood, along with tourism and other ocean-related economies.

"The effects of ocean acidification on whole ecosystems and their functioning are still poorly understood," said Micheli, a professor of biology. "In Ischia, we have gained new insights into what future oceans will look like and what key services, like food production and coastal production, will be lost when there is more carbon dioxide in the water."

Author: Nicole Kravec | Source: Stanford University [December 11, 2018]

NOAA's annual report card on the Arctic, released today at the American Geophysical Union fall meeting in Washington, D.C., measures the changing climate of the polar region including warmer air and ocean temperatures and declines in sea-ice that are driving shifts in animal habitats.

Eyeing the Arctic: The southern Greenland town of Narsaq. Photo taken during a NASA Operation IceBridge flight April 26, 2018 [Credit: NASA/Joe MacGregor]

Now in its 13th year, the 2018 Arctic Report Card is a peer-reviewed report that provides an annual status update on the region and compares these observations to the long-term record. It was compiled from the research of 81 scientists working for governments and academia in 12 nations. This information can be used to inform decisions by local, state and federal leaders as Arctic residents confront the challenges and opportunities posed by a rapidly changing climate and ecosystem.

"The environmental changes in the Arctic underscore why NOAA continues to invest in Arctic research and activities, which improve the nation's economic competitiveness, national security, and the sustainable management of natural resources," said retired Navy Rear Adm. Timothy Gallaudet, Ph.D., acting under secretary of commerce for oceans and atmosphere at NOAA, who led the news conference to release the report card. "This report will also help guide NOAA's priorities in better understanding the role of the Arctic in climate change and extreme weather; sustaining and growing fisheries; and supporting adaptation and economic opportunities in the region."


This year's report shows that the Arctic region experienced the second-warmest air temperatures ever recorded; the second-lowest overall sea-ice coverage; lowest recorded winter ice in the Bering Sea; and earlier plankton blooms due to early melting of sea ice in the Bering Sea.

In addition to annual updates on ocean temperature, snow cover, tundra greenness and melting on the Greenland Ice Sheet, the report card also includes reports on multi-year environmental changes, including a long-term population decline of the region's iconic wildlife species, the caribou. Other multi-year essays focused on the expansion northward of toxic harmful algae and significant concentrations of microplastic pollution that are transported by ocean currents into the Arctic Ocean from other parts of the global ocean.

Declining Arctic sea ice: The 2018 Arctic Report Card found the Arctic region had the second-lowest overall sea-ice coverage on record. The map shows the age of sea ice in the Arctic ice pack in March 1985 (left) and March 2018 (right) . Ice that is less than a year old is darkest blue. Ice that has survived at least 4 full years is white [Credit: Maps were provided by NOAA Climate.gov and based on data provided by Mark Tschudi./University of Colorado/ CCAR (NOAA Climate.gov)]

This report card is just one of many aspects of NOAA's role in the Arctic region. NOAA, alongside many partners, is monitoring Arctic conditions, pioneering innovative technologies, and creatively collecting data and other scientific information.

For example, new technology is revolutionizing our understanding of the Arctic's changing environment, beginning to fill critical gaps in ocean and atmospheric observations. This technology is unmanned, fast, cost-effective, sturdy enough to withstand icy temperatures, and able to collect quality data for lengthy periods. Further, NOAA Polar-orbiting satellites fly over the Arctic 28 times daily, collecting data vital to improve weather forecasts, help fisheries increase catch, and support safe, efficient navigation in challenging waters. Additionally, as Arctic waters become increasingly ice-free, and commerce and other interests grow, NOAA is working to update nautical charts and calculate tide and current predictions.

Source: National Oceanic and Atmospheric Administration (NOAA) [December 11, 2018]

Seventy percent of the current infrastructure in the Arctic has a high potential to be affected by thawing permafrost in the next 30 years. Even meeting the climate change targets of the Paris Agreement will not substantially reduce those projected impacts, according to a new study published in Nature Communications.

UAF researcher Vladimir Romanovsky poses near Fairbanks, Alaska in a place where permafrost has thawed, causing a surface disruption [Credit: University of Alaska Fairbanks]

"Much more needs to be done to prepare Alaska and Alaskans for the adverse consequences of coming changes in permafrost and climate," said Vladimir Romanovsky, a scientist with the University of Alaska Fairbanks Geophysical Institute who has been monitoring permafrost across Alaska for 25 years.

Permafrost is ground that is frozen year-round for a minimum of two years. When it thaws, it can change from solid earth into mud. In many cases, the ground will slump, leading to destructive failure in any structures erected there.

"These observations have led me to believe that the global warming is not a 'fake' but the reality," Romanovsky said. "And here, in Alaska, we are dealing already and will be dealing even more in the near future with this reality."

Romanovsky is one of the study's authors, along with researchers from Finland, Norway, Russia and Michigan. The research is the first to explicitly show the amount of fundamental infrastructure across the Northern Hemisphere that is at risk of structural failure from permafrost thaw caused by climate change.

The paper reports that by 2050, about three-quarters of the population now living on permafrost, about 3.6 million people, will be affected by damage to infrastructure from permafrost thaw. In Alaska, about 340 miles of the trans-Alaska oil pipeline traverses ground where near-surface permafrost may thaw by 2050.

"The results show that most fundamental Arctic infrastructure will be at risk, even if the Paris Agreement target is achieved," the authors write. However, after 2050, attaining the Paris Agreement goals would make a clear difference in potential damage to infrastructure.

The authors looked at measurements of ground temperature, annual thaw depth and other data to make their projections. They note that because of the uncertainties, the amount of infrastructure at risk from permafrost thaw is probably not much smaller than their estimate, but could be substantially larger.

Damage to industrial facilities such as pipelines could lead to major ecosystem disruption if it results in spills. Energy supplies, national security and general economic activity could be adversely affected as well, the authors write. The Yamal-Nenets region in northwestern Siberia is the source of more than one-third of the European Union's pipeline imports of natural gas, for example.

Many parts of the Arctic's infrastructure have relatively short lifespans. Planners and engineers need to know in detail where permafrost is most likely to thaw as they plan for replacements, upgrades and maintenance. This study mapped such areas at a resolution of 0.6 miles, allowing them to target mitigation where it is most needed.

Source: University of Alaska Fairbanks [December 11, 2018]

Our future on Earth may also be our past. In a study published in the Proceedings of the National Academy of Sciences, researchers show that humans are reversing a long-term cooling trend tracing back at least 50 million years. And it's taken just two centuries.

Epihippus gracilis, one of the many early horses found in the Hancock Mammal Quarry in Oregon, depicted around 30 million years ago. Their ancestors would have gotten their start in the Eocene [Credit: National Park Services]

By 2030, Earth's climate is expected to resemble that of the mid-Pliocene, going back more than 3 million years in geologic time. Without reductions in our greenhouse gas emissions, our climates by 2150 could compare to the warm and mostly ice-free Eocene, an epoch that characterized the globe 50 million years ago.

"If we think about the future in terms of the past, where we are going is uncharted territory for human society," says the study's lead author, Kevin Burke, who conducted the work while a graduate student in the lab of paleoecologist John "Jack" Williams, professor of geography at the University of Wisconsin-Madison. "We are moving toward very dramatic changes over an extremely rapid time frame, reversing a planetary cooling trend in a matter of centuries."

All of the species on Earth today had an ancestor that survived the Eocene and the Pliocene, but whether humans and the flora and fauna we are familiar with can adapt to these rapid changes remains to be seen. The accelerated rate of change appears to be faster than anything life on the planet has experienced before.

The new study builds upon work Williams and colleagues first published in 2007, which compared future climate projections to historical climate data from the early 20th century. The new study relies on extensive data about climate conditions to probe much deeper in Earth's geologic past and expand those comparisons.

"We can use the past as a yardstick to understand the future, which is so different from anything we have experienced in our lifetimes," says Williams. "People have a hard time projecting what the world will be like five or 10 years from now. This is a tool for predicting that -- how we head down those paths, and using deep geologic analogs from Earth's history to think about changes in time."

During the Eocene, Earth's continents were packed more closely together and global temperatures averaged 23.4 degrees Fahrenheit (13 degrees Celsius) warmer than they are today. Dinosaurs had recently gone extinct and the first mammals, like ancestral whales and horses, were spreading across the globe. The Arctic was occupied by swampy forests like those found today in the southern U.S.

Future climate analogs for the years 2020, 2050, 2100 and 2200 according to three well-established models. If greenhouse gas emissions are not curbed, the study says, the climate will continue to warm until it begins to resemble the Eocene in 2100 [Credit: Burke et al. 2018]

In the Pliocene, North and South America joined tectonically, the climate was arid, land bridges allowed animals to spread across continents and the Himalayas formed. Temperatures were between 3.2 and 6.5 degrees Fahrenheit (1.8 to 3.6 degrees Celsius) warmer than they are today.

For the study, Burke and Williams -- along with colleagues at the University of Bristol, Columbia University, University of Leeds, NASA Goddard Institute for Space Studies and the National Center for Atmospheric Research -- examined the similarities between future climate projections as set forth by the Intergovernmental Panel on Climate Change Fifth Assessment Report and several periods of geologic history.

These included the Early Eocene, the mid-Pliocene, the Last Interglacial (129 to 116 thousand years ago), the mid-Holocene (6,000 years ago), the pre-industrial era (before A.D. 1850) and the early 20th century.

They used Representative Concentration Pathway 8.5 (RCP8.5), which represents a future climate scenario in which we do not mitigate greenhouse gas emissions, and RCP4.5, a scenario in which we moderately reduce greenhouse gas emissions, and climate simulations using three different but well-established models: the Hadley Centre Coupled Model version 3, the Goddard Institute for Space Studies ModelE2-R and the Community Climate System Model.

While not without their flaws, each of these models represents the best available data and state-of-the-art techniques.

Under both scenarios and across each model, compared to previous eras, the Earth's climate most closely resembled the mid-Pliocene by 2030 (under RCP8.5) or 2040 (under RCP4.5). Under the greenhouse gas stabilization scenario of RCP4.5, the climate then stabilizes at mid-Pliocene-like conditions, but under the higher greenhouse gas emissions of RCP8.5, the climate continues to warm until it begins to resemble the Eocene in 2100, achieving Eocene-like conditions more broadly by 2150.

The models showed these deep-geological climates emerging first from the center of continents and then expanding outward over time. Temperatures rise, precipitation increases, ice caps melt and climates become temperate near the Earth's poles.

"Madison (Wisconsin) warms up more than Seattle (Washington) does, even though they're at the same latitude," Williams explains. "When you read that the world is expected to warm by 3 degrees Celsius this century, in Madison we should expect to roughly double the global average."


The study also showed that under RCP8.5, "novel" climates emerge across nearly 9 percent of the planet. These are conditions that do not have known geologic or historical precedent and they concentrate in eastern and southeastern Asia, northern Australia and the coastal Americas.

"Based on observational data, we are tracking on the high end of the emissions scenarios, but it's too soon to tell," says Burke. "We may be somewhere between RCP4.5 and RCP8.5, though if we increase our climate mitigation efforts -- like switching to renewable energy -- we could find ourselves closer to the low end."

About a decade ago, Swedish scientist Johan Rockström and colleagues introduced the idea of "safe operating space," referring to the climate conditions under which modern agricultural societies developed. By comparing to the deep past, Williams and Burke say, we are able to better understand the planetary boundaries and thresholds that delineate this space.

"The further we move from the Holocene, the greater the potential that we move out of safe operating space," says Williams, a faculty affiliate with the UW-Madison Nelson Institute Center for Climatic Research. "In the roughly 20 to 25 years I have been working in the field, we have gone from expecting climate change to happen, to detecting the effects, and now, we are seeing that it's causing harm. People are dying, property is being damaged, we're seeing intensified fires and intensified storms that can be attributed to climate change. There is more energy in the climate system, leading to more intense events."

In their paper, the researchers try to strike a balance between alarm and optimism. On the one hand, Earth is headed into the unknown in our children's and grandchildren's lifetimes. On the other, life has long proven to be resilient. And, Williams says, in many places we are moving away from fossil fuels toward more sustainable and carbon-free energy sources. But more needs to be done.

"We've seen big things happen in Earth's history -- new species evolved, life persists and species survive. But many species will be lost, and we live on this planet," says Williams. "These are things to be concerned about, so this work points us to how we can use our history and Earth's history to understand changes today and how we can best adapt."

Author: Kelly April Tyrrell | Source: University of Wisconsin-Madison [December 10, 2018]

New NASA research has found that increases in the rate at which Arctic sea ice grows in the winter may have partially slowed down the decline of the Arctic sea ice cover.

The sun setting over the Arctic sea ice pack, as observed during the Beaufort Gyre Exploration Project in October 2014 [Credit: NASA/Alek Petty]

As temperatures in the Arctic have warmed at double the pace of the rest of the planet, the expanse of frozen seawater that blankets the Arctic Ocean and neighboring seas has shrunk and thinned over the past three decades. The end-of-summer Arctic sea ice extent has almost halved since the early 1980s. A recent NASA study found that since 1958, the Arctic sea ice cover has lost on average around two-thirds of its thickness and now 70 percent of the sea ice cap is made of seasonal ice, or ice that forms and melts within a single year.

But at the same time that sea ice is vanishing quicker than it has ever been observed in the satellite record, it is also thickening at a faster rate during winter. This increase in growth rate might last for decades, a new study accepted for publication in Geophysical Research Letters found.

This does not mean that the ice cover is recovering, though. Just delaying its demise.

"This increase in the amount of sea ice growing in winter doesn't overcome the large increase in melting we've observed in recent decades," said Alek Petty, a sea ice scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study. "Overall, thickness is decreasing. Arctic sea ice is still very much in decline across all seasons and is projected to continue its decline over the coming decades. "

Petty and his team used climate models and observations of sea ice thickness from the European Space Agency's CryoSat-2 satellite to explore sea ice growth variability across the Arctic. The climate model results compared well both with CryoSat-2's measurements and the results of another commonly used Arctic sea ice model, giving the authors confidence in the climate model's ability to capture Arctic sea ice variability.

"The global climate model seems to do a good job of capturing the Arctic sea ice state and shows that most of the thickness change in the central Arctic is from thermodynamics, that is, ice formation and ice melt, although around the Arctic sea ice edge dynamics, which is ice transport, can play a bigger role," Petty said.

These model simulations showed that in the 1980s, when Arctic sea ice was on average 6.6 feet thick in October, about 3.3 extra feet of ice would form over the winter. That rate of growth has increased and may continue to do so for several more decades in some regions of the Arctic; in the coming decades, we could have an ice pack that would on average be only around 3.3 feet thick in October, but could experience up to 5 feet of ice growth over the winter.

It seems counterintuitive: how does a weakening ice cover manage to grow at a faster rate during the winter than it did when the Arctic was colder and the ice was thicker and stronger?

"Our findings highlight some resilience of the Arctic sea ice cover," Petty said. "If we didn't have this negative feedback, the ice would be declining even faster than it currently is. Unfortunately, the positive feedback loop of summer ice melt and increased solar absorption associated with summer ice melting still appears to be dominant and continue to drive overall sea ice declines."

Nonetheless, the increased rate of sea ice thickening in winter has other implications. As ice forms at the ocean surface, it releases a lot of the salty and dense water from which it originated, which sinks and increases the mixing of waters in the upper ocean. The more ice formation that takes place, the more mixing we expect to see in the upper ocean. Increases in this ice formation and mixing during winter may help mitigate the strong freshening of the Arctic Ocean's surface waters that has been observed in recent decades due to increased summer melt.

"This is altering the seasonal balance and the salinity distribution of the upper ocean in the Arctic; it's changing when we have fresh water, when we have salty water and how deep and seasonal that upper oceanic mixed layer is," Petty said. "And that's all going to mean that local micro-organisms and ecosystems have to adapt to these rapidly evolving conditions."

Petty's projections found that, by the middle of the century, the strong increases in atmospheric and oceanic temperatures will outweigh the mechanism that allows ice to regrow faster, and the Arctic sea ice cover will decline further. The study predicted that the switch will happen once the sea ice is less than 1.6 feet thick at the beginning of winter, or its concentration -the percentage of an area that is covered in sea ice- is less than 50 percent.

"This negative feedback mechanism increasing ice growth is unlikely to be sufficient in preventing an ice-free Arctic this century," Petty and his colleagues concluded.

Author: Maria-José Viñas | Source: NASA's Goddard Space Flight Center [December 06, 2018]

Surface melting across Greenland's mile-thick ice sheet began increasing in the mid-19th century and then ramped up dramatically during the 20th and early 21st centuries, showing no signs of abating, according to new research published in the journal Nature. The study provides new evidence of the impacts of climate change on Arctic melting and global sea level rise.

Large rivers form on the surface of Greenland each summer, rapidly moving meltwater from the ice sheet to the ocean [Credit: Sarah Das, Woods Hole Oceanographic Institution]

"Melting of the Greenland Ice Sheet has gone into overdrive. As a result, Greenland melt is adding to sea level more than any time during the last three and a half centuries, if not thousands of years," said Luke Trusel, a glaciologist at Rowan University's School of Earth & Environment and former post-doctoral scholar at Woods Hole Oceanographic Institution, and lead author of the study. "And increasing melt began around the same time as we started altering the atmosphere in the mid-1800s."

"From a historical perspective, today's melt rates are off the charts, and this study provides the evidence to prove this" said Sarah Das, a glaciologist at Woods Hole Oceanographic Institution (WHOI) and co-author of the study. "We found a fifty percent increase in total ice sheet meltwater runoff versus the start of the industrial era, and a thirty percent increase since the 20th century alone."

Ice loss from Greenland is one of the key drivers of global sea level rise. Icebergs calving into the ocean from the edge of glaciers represent one component of water re-entering the ocean and raising sea levels. But more than half of the ice-sheet water entering the ocean comes from runoff from melted snow and glacial ice atop the ice sheet. The study suggests that if Greenland ice sheet melting continues at "unprecedented rates" -- which the researchers attribute to warmer summers -- it could accelerate the already fast pace of sea level rise.

"Rather than increasing steadily as climate warms, Greenland will melt increasingly more and more for every degree of warming. The melting and sea level rise we've observed already will be dwarfed by what may be expected in the future as climate continues to warm," said Trusel.


To determine how intensely Greenland ice has melted in past centuries, the research team used a drill the size of a traffic light pole to extract ice cores from the ice sheet itself and an adjacent coastal ice cap, at sites more than 6,000 feet above sea level. The scientists drilled at these elevations to ensure the cores would contain records of past melt intensity, allowing them to extend their records back into the 17th century. During warm summer days in Greenland, melting occurs across much of the ice sheet surface. At lower elevations, where melting is the most intense, meltwater runs off the ice sheet and contributes to sea level rise, but no record of the melt remains. At higher elevations, however, the summer meltwater quickly refreezes from contact with the below-freezing snowpack sitting underneath. This prevents it from escaping the ice sheet in the form of runoff. Instead, it forms distinct icy bands that stack up in layers of densely packed ice over time.

The core samples were brought back to ice core labs at the U.S. National Science Foundation Ice Core Facility in Denver, Colo., WHOI in Woods Hole, Mass., Wheaton College in Norton, Mass., and the Desert Research Institute in Reno, Nev. where the scientists measured physical and chemical properties along the cores to determine the thickness and age of the melt layers. Dark bands running horizontally across the cores, like ticks on a ruler, enabled the scientists to visually chronicle the strength of melting at the surface from year to year. Thicker melt layers represented years of higher melting, while thinner sections indicated years with less melting.

Combining results from multiple ice cores with observations of melting from satellites and sophisticated climate models, the scientists were able to show that the thickness of the annual melt layers they observed clearly tracked not only how much melting was occurring at the coring sites, but also much more broadly across Greenland. This breakthrough allowed the team to reconstruct meltwater runoff at the lower-elevation edges of the ice sheet -- the areas that contribute to sea level rise.

Study lead author and WHOI post-doc Dr. Luke Trusel (now at Rowan University) takes field measurements of a section of ice core from Greenland before packing it for transport home [Credit: Sarah Das, Woods Hole Oceanographic Institution]

Ice core records provide critical historical context because satellite measurements -- which scientists rely on today to understand melting rates in response to changing climate -- have only been around since the late 1970s, said Matt Osman, a graduate student in the MIT-WHOI Joint Program and co-author of the study.

"We have had a sense that there's been a great deal of melting in recent decades, but we previously had no basis for comparison with melt rates going further back in time," he said. "By sampling ice, we were able to extend the satellite data by a factor of 10 and get a clearer picture of just how extremely unusual melting has been in recent decades compared to the past."

Trusel said the new research provides evidence that the rapid melting observed in recent decades is highly unusual when put into a historical context.

"To be able to answer what might happen to Greenland next, we need to understand how Greenland has already responded to climate change," he said. "What our ice cores show is that Greenland is now at a state where it's much more sensitive to further increases in temperature than it was even 50 years ago."

One noteworthy aspect of the findings, Das said, was how little additional warming it now takes to cause huge spikes in ice sheet melting.

"Even a very small change in temperature caused an exponential increase in melting in recent years," she said. "So the ice sheet's response to human-caused warming has been non-linear." Trusel concluded, "Warming means more today than it did in the past."

Additional co-authors are: Matthew B. Osman, MIT/WHOI Joint Program in Oceanography; Matthew J. Evans, Wheaton College; Ben E. Smith, University of Washington; Xavier Fettweis, University of Leige; Joseph R. McConnell, Desert Research Institute; and Brice P. Y. Noël and and Michiel R. van den Broeke Utrecht University.

This research was funded by the US National Science Foundation, institutional support from Rowan University and Woods Hole Oceanographic Institution, the US Department of Defense, the Netherlands Organization for Scientific Research, the Netherlands Earth System Science Center, and the Belgian National Fund for Scientific Research.

Source: Woods Hole Oceanographic Institution [December 05, 2018]

Global carbon emissions are set to hit an all-time high in 2018 - according to researchers at the University of East Anglia (UEA) and the Global Carbon Project.

A coal-fired power plant in Bergheim. Germany. Coal use in power stations is a major source of CO2 emissions [Credit: EPA-EFE]

A projected rise of more than 2 per cent has been driven by a solid growth in coal use for the second year in a row, and sustained growth in oil and gas use.

The news is a further call to action for governments at the UN Climate Change Conference (COP 24) in Katowice this week.

But the research team say energy trends are changing and that there is still time to address climate change if efforts to curb carbon emissions rapidly expand in all sectors of the economy.

The new data for 2018, published today simultaneously in the journals Nature, Earth System Science Data and Environmental Research Letters, reveals that global emissions from burning fossil fuels are expected to reach 37.1 billion tonnes of CO2 in 2018.

CO2 emissions have now risen for a second year, after three years of little-to-no growth from 2014 to 2016. The rise this year is projected at 2.7 per cent (+1.8 to +3.7 per cent). In 2017 it was 1.6 per cent.

The 10 biggest emitters in 2018 are China, the US, India, Russia, Japan, Germany, Iran, Saudi Arabia, South Korea, and Canada. The EU as a whole region of countries ranks third.

Lead researcher Prof Corinne Le Quéré, Director of the Tyndall Centre for Climate Change Research and Professor of Climate Change Science and Policy at UEA, said: "We are seeing a strong growth of global CO2 emissions once again.

"Emissions need to peak and rapidly decrease to address climate change. With this year's growth in emissions, it looks like the peak is not yet in sight.

"To limit global warming to the Paris Agreement goal of 1.5°C, CO2 emissions would need to decline by 50 per cent by 2030 and reach net zero by around 2050. We are a long way from this and much more needs to be done because if countries stick to the commitments they have already made, we are on track to see 3°C of global warming.

"This year we have seen how climate change can already amplify the impacts of heatwaves worldwide. The California wildfires are just a snapshot of the growing impacts we face if we don't drive emissions down rapidly."

What is driving the rise?

This year's rising emission figures are largely due to solid growth in coal use, but coal still remains below its historical high in 2013. Coal use may soon exceed this 2013 peak if current growth continues.

Oil use is growing strongly in most regions, with a rise in emissions from cars and lorries, including in the US and Europe. Flights have also contributed to the oil rise. Gas use has grown almost unabated in recent years.

Prof Le Quéré said: "The growing global demand for energy is outpacing decarbonisation for now. This needs to change, and change quickly to address climate change.

"We need strong policy and economic support for rapid deployment of low carbon technologies to cut emissions across the energy and transport sectors, from buildings and from industry.

Global carbon emissions are set to hit an all-time high in 2018 -- according to researchers at the University of East Anglia and the Global Carbon Project. A projected rise of more than 2 per cent has been driven by a solid growth in coal use for the second year in a row, and sustained growth in oil and gas use [Credit: Global Carbon Project]

"Energy trends are changing rapidly, with coal use decreasing in many parts of the world and still below its 2013 level globally, and an explosion in wind and solar energy. But while renewables are rising fast, it is not yet enough to reverse global emissions trends.

"The rapid actions needed to address climate change also need to be fair to all generations," she added.

Dr Glen Peters, a Research Director at the CICERO Center for International Climate Research in Oslo, who led the emissions analysis, said: "Global commitments made in Paris in 2015 to reduce emissions are not yet being matched by proportionate actions.

"Despite rapid growth in low carbon technologies such as solar and wind power, electric vehicles, and batteries, not nearly enough is being done to support policies that limit the amount of carbon dioxide that is put into the atmosphere.

"The rise in emissions in 2017 could be seen as a one-off, but the growth rate in 2018 is even higher, and it is becoming crystal clear the world is so far failing in its duty to steer onto a course consistent with the goals set out in the Paris Agreement in 2015."

CO2 emissions from deforestation and other human activities on land contributed an additional 5 billion tonnes of CO2 this year, bringing total CO2 emissions to 41.5 billion tonnes of CO2. The global trends in those emissions are unclear due to large uncertainties in the data.

Concentrations of carbon dioxide (CO2) in the atmosphere are set to increase by around 2.3 parts per million on average in 2018 in response to continued CO2 emissions, to reach about 407 parts per million over the year. This is 45 per cent above pre-industrial levels. The rise of CO2 in the atmosphere is the main cause of climate change.

The good news

Countering rising global emissions are 19 countries where emissions have reduced and their economy has grown. Aruba, Barbados, the Czech Republic, Denmark, France, Greenland, Iceland, Ireland, Malta, the Netherlands, Romania, Slovakia, Slovenia, Sweden, Switzerland, Trinidad and Tobago, the UK, the US, and Uzbekistan have all decreased their emissions over the past decade (2008-2017).

Deployment of renewable energy worldwide is accelerating exponentially, with electricity generation growing at 15 per cent per year on average over the last decade. But this has not been enough to offset the growth in fossil energy because renewables are growing from a low base. This is changing rapidly.

Christiana Figueres, Mission 2020 campaign group leader and lead author of the Nature Commentary, said: "Global CO2 emissions must start to fall from 2020 if we are to meet the temperature goals of the Paris agreement, but this is within our grasp. We have already achieved things that seemed unimaginable just a decade ago.

"Exponential progress in key solutions is happening and on track to displace fossil fuels. Renewable energy technology costs have dropped by 80 per cent in a decade, and today, over half of all new energy generation capacity is renewable. Before 2015 many people thought the Paris Agreement was impossible, yet thousands of people and institutions made the shift from impossible to unstoppable. The same is true of decarbonizing the economy. Propelled by the pursuit of clean air, jobs and energy-independence among other benefits, the intrepid, collective efforts of young people, civil society, businesses, investors, cities and states are charting the course to net zero emissions by 2050."

How different countries compare

Almost all countries have contributed to the rise in global emissions, either through growth in emissions or through reductions that are slower than expected. China's emissions account for 27 per cent of the global total, having grown an estimated 4.7 per cent (+2 per cent to +7.4 per cent) in 2018 and reaching a new all-time high. The growth in emissions is linked to construction activity and economic growth, part of which may be due to temporary stimulus-driven credit growth. Energy from renewables is growing by 25 per cent per year, but from a low base.

Emissions in the US account for 15 per cent of the global total, and look set to have grown about 2.5 per cent (+0.5 per cent to +4.5 per cent) in 2018 after several years in decline. The new rise is due to robust growth in oil use of about 1.4 per cent, associated with an increase in car journeys, and gas of about 7.6 per cent. Emissions from coal use look set to have decreased by around -2.1 per cent in 2018, continuing a shift away from coal, with a 40 per cent decrease in CO2 emissions from coal since 2007, mainly towards gas, and more recently also towards renewables for power generation.

EU emissions account for 10 per cent of global emissions and a small decline of around -0.7 per cent is projected, well below the declines of ?2 per cent per year in the decade up to 2014. Estimated declines in coal and gas use due to the growth in renewable energy have been partially offset by a growth in oil use. The amount of fuel used for road transport and flights has surged by around 4 per cent in the EU. Overall EU emissions are still near or above their 2014 levels.

India's emissions, accounting for 7 per cent of the global total, have continued to grow by around 6.3 per cent, as their economy booms. Wind and solar are growing fast, albeit from a low base.

Emissions in the rest of the world, the remaining 42 per cent of global emissions, are expected to grow about 1.8 per cent (+0.5 per cent to +3.0 per cent) this year. The five countries contributing most to the rest-of-the-word growth in global emissions in the last decade are Saudi Arabia, Iran, Turkey, Iraq and South Korea.

Source: University of East Anglia [December 05, 2018]

The pattern of uneven sea level rise over the last quarter century has been driven in part by human-caused climate change, not just natural variability, according to a new study.

Altimeter era sea level trends [Credit: John T. Fasullo]

The findings suggest that regions of the world where seas have risen at higher than average rates -- including the Eastern Seaboard of the United States and the Gulf of Mexico -- can expect the trend to continue as the climate warms.

The study, published today in the Proceedings of the National Academy of Sciences, was authored by scientists John Fasullo at the National Center for Atmospheric Research (NCAR) and Steve Nerem at the University of Colorado Boulder.

"By knowing that climate change is playing a role in creating these regional patterns, we can be more confident that these same patterns may linger or even intensify in the future if climate change continues unabated," Fasullo said. "With sea levels projected to rise a couple of feet or more this century on average, information about expected regional differences could be critical for coastal communities as they prepare."

The research was funded by the National Science Foundation, which is NCAR's sponsor, the NASA Sea Level Change Team, and the U.S. Department of Energy.

Finding the signal of climate change

For the study, Fasullo and Nerem, both members of the NASA Sea Level Change Team, analyzed the satellite altimetry sea level record, which includes measurements of sea surface heights stretching back to 1993. They mapped global average sea level rise as well as how particular regions deviated from the average.

For example, the oceans surrounding Antarctica and the U.S. West Coast have had lower-than-average sea level rise, while the U.S. East Coast and Southeast Asia, including the Philippines and Indonesia, have experienced the opposite. In some parts of the world, the rate of local sea level rise has been as much as twice the average.

Regional differences in sea level rise are influenced by where heat is stored in the ocean (since warm water expands to fill more space than cold water) and how that heat is transported around the globe by currents and wind. Uneven sea level rise is also influenced by ice sheets, which lose mass as they melt and shift the gravitational forces affecting regional sea surface height.

Natural shifts in ocean cycles -- including the Pacific Decadal Oscillation, a pattern of sea surface temperatures similar to El Niño but longer lasting -- are therefore known to affect sea levels. So scientists were not surprised to find that as the ocean rises, it rises unevenly. But it's been difficult to say whether these natural cycles were the dominant influence on regional differences.

To investigate the role of climate change, the scientists turned to two sets of climate model runs, known as "large ensembles": one created using the NCAR-based Community Earth System Model and one created using the Earth System Model at the National Oceanic and Atmospheric Administration. These large ensembles -- many model simulations by the same model, describing the same time period -- allow researchers to disentangle natural variability from the impacts of climate change. With enough runs, these impacts can be isolated even when they are relatively small compared to the impacts from natural variability.

The climate models suggest that in regions that have seen more or less sea level rise than average, as much as half of that variation may be attributed to climate change. The scientists also found that the impacts from climate change on regional sea level rise sometimes mimic the impacts from natural cycles.

"It turns out the sea level rise response to climate change in the Pacific resembles what happens during a particular phase of the Pacific Decadal Oscillation," Fasullo said. "This explains why it's been so difficult to determine how much of the pattern was natural or not, until now."

Improving forecasts

The research findings have implications for local officials, who are interested in improved forecasts of sea level rise for the areas they oversee. In the past, forecasters have had to rely on the global rate of change -- about 3 millimeters a year and accelerating -- and knowledge of the uneven regional impacts associated with continued melting of the ice sheets covering Greenland and Antarctica.

The findings add the possibility that the regional patterns of sea level rise tied to climate change can also be included, because the models predict that the regional patterns observed in the satellite measurements will continue into the future.

"We now have a new tool -- long-term satellite altimeter measurements -- that we can use to help stakeholders who need information for specific locations," said Nerem, a fellow of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder and a professor of aerospace engineering.

Author: Laura Snider | Source: National Center for Atmospheric Research [December 03, 2018]

New research reveals the extinction of plant or animal species from extreme environmental change increases the risk of an 'extinction domino effect' that could annihilate all life on Earth.

Virtual earths modelling shows an 'extinction domino effect' risk ten times higher than forecast, indicating rising global temperatures due to climate change could wipeout entire species [Credit: Flinders University]

This would be the worst-case scenario of what scientists call 'co-extinctions', where an organism dies out because it depends on another doomed species, with the findings published in the journal Scientific Reports.

Think of a plant's flower pollinated by only one species of bee -- if the bee becomes extinct, so too will the plant eventually.

"Even the most resilient species will inevitably fall victim to the synergies among extinction drivers as extreme stresses drive ecosystems to collapse." says lead author Dr Giovanni Strona of the European Commission's Joint Research Centre based in Ispra in northern Italy.

Researchers from Italy and Australia simulated 2,000 'virtual earths' linking animal and plant species. Using sophisticated modelling, they subjected the virtual earths to catastrophic environmental changes that ultimately annihilated all life.

Examples of the kinds of catastrophes they simulated included runaway global warming, scenarios of 'nuclear winter' following the detonation of multiple atomic bombs, and a large asteroid impact.

"What we were trying to test is whether the variable tolerances to extreme global heating or cooling by different species are enough to explain overall extinction rates,"


"But because all species are connected in the web of life, our paper demonstrates that even the most tolerant species ultimately succumb to extinction when the less-tolerant species on which they depend disappear."

"Failing to take into account these co-extinctions therefore underestimates the rate and magnitude of the loss of entire species from events like climate change by up to 10 times," says co-author Professor Bradshaw of Flinders University in South Australia

Professor Bradshaw and Dr Strona say that their virtual scenarios warn humanity not to underestimate the impact of co-extinctions.

"Not taking into account this domino effect gives an unrealistic and exceedingly optimistic perspective about the impact of future climate change", warns Professor Bradshaw.

It can be hard to imagine how the demise of a small animal or plant matters so much, but the authors argue that tracking species up to total annihilation demonstrates how the loss of one can amplify the effects of environmental change on the remainder.

"Another really important discovery was that in the case of global warming in particular, the combination of intolerance to heat combined with co-extinctions mean that 5-6 degrees of average warming globally is enough to wipe out most life on the planet", says Dr Strona.

Professor Bradshaw further warns that their work shows how climate warming creates extinction cascades in the worst possible way, when compared to random extinctions or even from the stresses arising from nuclear winter.

Source: Flinders University [November 29, 2018]

Earth scientists are able to travel far back in time to reconstruct the geological past and paleoclimate to make better predictions about future climate conditions. Scientists at the Netherlands Institute for Sea Research (NIOZ) and Utrecht University succeeded in developing a new indicator (proxy) of ancient CO2-levels, using the organic molecule phytane, a debris product of chlorophyll. This new organic proxy not only provides the most continuous record of CO2-concentrations ever, it also breaks a record in its time span, covering half a billion years. The data show the present idea that rises in CO2-levels that used to take millions of years, are now happening in a century. These findings are published in Science Advances.

Cells of coccolithophore genera Gephyrocapsa grown in laboratory culture [Credit: ERC]

As CO2 increases today, it's vital to understand what impact these changes will have. To better predict the future, we must understand long-term changes in CO2 over geologic history. Direct measurements of past CO2 are available, e.g. bubbles in ice cores containing ancient gases. However, ice cores have a limited time span of one million years. To go farther back in time, earth scientists have developed various indirect measurements of CO2 from proxies e.g. from algae, leaves, ancient soils and chemicals stored in ancient sediments to reconstruct past environmental conditions.

Phytane, a new way to travel in time

A new proxy, using a degradation product of chlorophyll, allows geochemists to infer a continuous record of historic CO2-levels in deep time. Scientists at NIOZ have recently developed phytane as a promising new organic proxy that uncovers half a billion years of CO2-levels in the oceans, from the Cambrian until recent times.

Using the new proxy, they were able to make the most continuous record of ancient carbon dioxide levels ever. "We developed and validated a new way to time travel -- going farther back in time and to more places," says NIOZ-scientist Caitlyn Witkowski. "With phytane, we now have the longest CO2-record with one single marine proxy. This new data is invaluable to modelers who can now more accurately make predictions of the future."

Witkowski and colleagues selected more than 300 samples of marine sediments from deep sea cores and oils from all over the globe, reflecting the majority of geological periods in the last 500 million years.

Fossil molecules

Past chemical reactions can be 'stored' in fossil molecules, and so they may reflect various ancient environmental conditions. Geochemists are able to 'read' these conditions, such as seawater temperature, pH, salinity and CO2-levels. Organic matter, such as phytane, reflects the pressure of CO2 in ocean water or the atmosphere (pCO2).

For her research Witkowski collected seawater with fresh, modern algae to test potential indicators of the past [Credit: Caitlyn Witkowski]

Little green miracles

Although all organic matter has the potential to reflect CO2, phytane is special. Phytane is the pigment responsible for our green world. Anything that uses photosynthesis to absorb sunlight, including plants, algae, and some species of bacteria, has chlorophyll from which phytane comes. Plants and algae take in CO2 and produce oxygen. Without these little green miracles, our world just wouldn't be the same.

Because chlorophyll is found all around the world, phytane is also everywhere and is a major constituent of decayed and fossilized biomass. "Phytane doesn't chemically change over the course of time, even if it is millions of years old," Witkowski says.

Carbon isotope fractionation

CO2 of the past is estimated from organic matter, such as phytane, through the phenomenon of carbon isotope fractionation during photosynthesis. When taking up CO2, plants and algae prefer the light carbon isotope (12C) over the heavy carbon isotope (13C). They only use the heavy carbon isotope when CO2-levels in the surrounding water or atmosphere are low. The proportion between these two isotopes therefore reflects the level of carbon dioxide in the environment at the moment of growth.

This also explains why Witkowski didn't use terrestrial plants as a source for her research, exclusively using phytane from (fossilized) marine sources. The plant world is divided into so-called C3- and C4-plants, each with their own unique ratio of light-to-heavy carbon. Phytoplankton all have very similar ratios compared to their plant counterparts. Witkowski: "By choosing only marine sources, we could limit uncertainty of the phytane source in the dataset."

"In our data, we see high levels of carbon dioxide, reaching 1000 ppm as opposed to today's 410 ppm. In this respect, present day levels are not unique, but the speed of these changes have never been seen before. Changes that typically take millions of years are now happening in a century. This additional CO2-data may help us understand the future of our planet." In future research, phytane can be used to go even further back in time than the Phanerozoic, the earliest found in two billion-year-old samples.

Source: Royal Netherlands Institute for Sea Research [November 28, 2018]

New research has shed light on the origin and extinction of a giant, shaggy Ice Age rhinoceros known as the Siberian unicorn because of its extraordinary single horn.

Australian scientists believe the Siberian unicorn was a victim of climate change [Credit: WikiCommons]

An international team of researchers from Adelaide, Sydney, London, the Netherlands, and Russia, have settled a long-standing debate about the relationship of the Siberian unicorn to living rhinos, and revealed that it survived much later than previously believed, overlapping in time with modern humans.

Published in the journal Nature Ecology and Evolution and led by London's Natural History Museum, the researchers say the Siberian unicorn became extinct around 36,000 years ago. This was most likely because of reduction in steppe grassland where it lived – due to climate change rather than the impact of humans.

Today there are just five surviving species of rhino, although in the past there have been as many as 250 species.

Weighing up to 3.5 tonnes with a single enormous horn, the Siberian unicorn (Elasmotherium sibiricum), which roamed the steppe of Russia, Kazakhstan, Mongolia, and Northern China, was undoubtedly one of the most impressive.

Skeleton of the rhino at the Stavropol Museum [Credit: Igor Doronin]

Genetic analyses performed at the University of Adelaide's Australian Centre for Ancient DNA (ACAD), however, have shown that the Siberian unicorn was the last surviving member of a unique family of rhinos.

"The ancestors of the Siberian unicorn split from the ancestors of all living rhinos over 40 million years ago," says co-author and ACAD researcher Dr. Kieren Mitchell, who analysed the DNA of the Siberian unicorn. It is the first time DNA has ever been recovered from E. sibiricum.

"That makes the Siberian unicorn and the African white rhino even more distant cousins than humans are to monkeys."

This new genetic evidence overturns previous studies that suggested the Siberian unicorn was a very close relative of the extinct woolly rhino and living Sumatran rhino.

It had long been assumed that the Siberian unicorn went extinct well before the last Ice Age, perhaps as much as 200,000 years ago.

Artist’s impression of Elasmotherium [Credit: © W. S. Van der Merwe/Natural History Museum]

In this study 23 Siberian unicorn bone specimens were dated, confirming that the species survived until at least 39,000 years ago, and possibly as late as 35,000 years ago. The Siberian unicorn's final days were shared with early modern humans and Neanderthals.

"It is unlikely that the presence of humans was the cause of extinction," says co-author Professor Chris Turney, climate scientist at the University of New South Wales.

"The Siberian unicorn appears to have been badly hit by the start of the ice age in Eurasia when a precipitous fall in temperature led to an increase in the amount of frozen ground, reducing the tough, dry grasses it lived on and impacting populations over a vast region."

Other species that shared the Siberian unicorn's environment were either less reliant on grass – like the woolly rhino – or more flexible in their diet – like the saiga antelope – and escaped the Siberian unicorn's fate, though the woolly rhino eventually became extinct 20,000 years later.

Author: Robyn Mills | Source: University of Adelaide [November 27, 2018]

The scientists made this discovery when they compared neodymium isotope signatures of deep sea sediment samples from both regions of the Atlantic. Their paper - 'Major intensification of Atlantic overturning circulation at the onset of Paleogene greenhouse warmth' - published in Nature Communications, reveals that the more vigorous circulation together with an increase in atmospheric CO2 led to a climatic tipping point. With a resulting more even distribution of heat over the earth, a long-term cooling phase ended and the world headed into a new greenhouse period.

Collecting deep sea sediments which are valuable archives of ocean circulation and past climates [Credit: Department of Earth Sciences]

Neodymium (Nd) isotopes are used as a tracer of water masses and their mixing. Surface waters acquire a Nd-isotope signature from surrounding land masses through rivers and wind-blown dust. When surface waters sink to form a deep-water mass, they carry their specific Nd-isotope signature with them. As a deep-water mass flows through the ocean and mixes with other water masses, its Nd-isotope signature is incorporated into sediments. Deep sea sediments are valuable archives of ocean circulation and past climates.

The story revealed in this paper begins at the end of the Cretaceous period (ending 66 million years ago), when the world was between two greenhouse states. Climate had been cooling for tens of millions of years since the peak hothouse conditions of the mid-Cretaceous, around 90 million years ago. Despite long-term cooling, temperatures and sea level at the end of the Cretaceous period were higher than at present day.

Dr Sietske Batenburg says: 'Our study is the first to establish how and when a deep-water connection formed. At 59 million years ago, the Atlantic Ocean truly became part of the global thermohaline circulation, the flow that connects four of the five main oceans.'

Deep sea sediments are valuable archives of ocean circulation and past climates [Credit: Department of Earth Sciences]

The Atlantic Ocean was still young, and the North and South Atlantic basins were shallower and narrower than today. The equatorial gateway between South America and Africa only allowed a shallow, surface-water connection for much of the late Cretaceous period. Active volcanism formed underwater mountains and plateaus that blocked deep-water circulation. In the South Atlantic, the Walvis Ridge barrier formed above an active volcanic hotspot. This ridge was partially above sea level and formed a barrier for the flow of deep-water masses.

As the Atlantic Ocean continued to open, the oceanic crust cooled and subsided. Basins became deeper and wider, and submarine plateaus and ridges sank, along with the crust. At some point, deep water from the Southern Ocean was able to flow north across the Walvis Ridge and fill the deeper parts of the Atlantic basins.

From 59 million years ago onwards, Nd-isotope signatures from the North and South Atlantic were remarkably similar. This may indicate that one deep-water mass, likely originating from the south, made its way through the Atlantic Ocean and filled the basin from deep to intermediate depths. The enhanced deep water exchange, together with increasing atmospheric CO2, may have enabled a more efficient distribution of heat over the planet.

This is a neodymium isotope ratio [Credit: Department of Earth Sciences]

This study shows that to understand the role of ocean circulation in past greenhouse climates, it is important to understand the different roles of geography and climate.

The current rate of climate change by CO2 emissions from human activity by far surpasses the rate of warming during past greenhouse climates. Studying ocean circulation during the most recent greenhouse interval in the geologic past may provide clues as to how ocean circulation might develop in the future, and how heat will be distributed over the planet by ocean currents.

This research is the result of an international collaboration with the Goethe-University Frankfurt; the Ruprecht-Karls-University of Heidelberg; the GEOMAR Helmholtz Centre for Ocean Research Kiel; the Federal Institute for Geosciences and Natural Resources in Hannover; the Royal Holloway University of London and the University of Oxford.

The sediments for this study were all taken from long ocean drill cores. The International Ocean Discovery Program (IODP) coordinates scientific expeditions to drill the ocean floor to recover these sediments, and stores the sediment cores so that they are available to the whole scientific community.

Source: University of Oxford [November 26, 2018]