Critically endangered South American forests thought to be the result of climate change were actually spread by ancient communities, archaeologists have found.
Campos da Serra y Floresta de Araucari [Credit: Copyright Jose Iriarte]
Huge swathes of land in Chile, Brazil and Argentina are covered with millions of Araucaria, or monkey puzzle trees, thanks to people planting or cultivating them more than a thousand years ago, a new study shows. Recent logging means the landscape is now one of the world's most at-risk environments.
It had been thought the forests expanded due to wetter and warmer weather. But the research shows the rapidly expanding pre-Columbian population of South America, Southern Jê communities, were really responsible.
New excavations and soil analysis shows the forests, still hugely culturally and economically important to people living in South America, expanded between 1,410 and 900 years ago because of population growth and cultural changes.
Dr Mark Robinson, from the University of Exeter, who led the British Academy and AHRC-FAPESP-funded research, said: "Our research shows these landscapes were man-made. Communities settled on grassland, and then - perhaps because they modified the soil, protected seedlings or even planted trees - established these forests in places where geographically they shouldn't have flourished."
Monkey puzzle forests [Credit: Copyright Mark Robinson]
The forests date back to the period when dinosaurs roamed. The iconic monkey puzzle tree, or Parana pine, has grown in the region for thousands of years. Its nuts were one of the most important food sources for ancient communities, attracted game for hunting when nuts were ripe. They were also a valuable source of timber, fuel and resin, and became an integral part of southern Jê cosmology. Communities still call themselves "people of the Araucaria", and hold festivals to celebrate the forests.
Of the 19 species of Araucaria tree, five are classified as endangered and two, including the Brazilian Araucaria angustifolia, are critically endangered. Reports from the late 1800s describe trees with diameters of over 2 m, reaching 42 m in height. Modern trees are only around 17.7 m tall.
The archaeological analysis began because the experts, from the University of Exeter, University of Reading, University of São Paulo, University of New Mexico, Universidade Federal de Pelotas and Universidade do Sul de Santa Catarina, noticed that in areas of low human activity forests are limited to south-facing slopes, whereas in areas of extensive archaeology, forests cover the entire landscape. They were able to analyse soil isotopes reflecting vegetation and archaeological evidence from Campo Belo do Sul, Santa Catarina State, Brazil, to test whether this pattern was directly related to past human activity.
The study shows the forests first expanded around 4,480 to 3,200 years ago, most likely near streams, and this may have been caused by a wetter climate. But a more rapid and extensive expansion across the whole region later happened between 1,410 and 900 years ago, when forests expanded into highland areas. The weather during this time was dry and less humid. This expansion of the forests coincides with population growth and increasingly complex and hierarchical societies in South America.
Monkey puzzle forests [Credit: Copyright Mark Robinson]
The expansion in forests reached a peak around 800 years ago. The number of people in South America declined 400 years ago when European settlers arrived in the area. The population did not begin to recover until the 19 century, when loggers began exploiting the Araucaria forests for timber.
Professor José Iriarte, from the University of Exeter, another member of the research team, said: "This study shows the Araucaria forests were expanded beyond their natural boundaries, they were used sustainably for hundreds of years, and conservation strategies must reflect this so they balance protection, heritage and economic development."
A shocking study in the journal Science by the University of Queensland, Wildlife Conservation Society (WCS), and University of Northern British Columbia confirms that one third of the world's protected areas - an astonishing 2.3 million square miles or twice the size of the state of Alaska - are now under intense human pressure including road building, grazing, and urbanization.
Some of these least impacted protected areas include Madidi National Park in Boliviawhere WCS has made considerable conservation investments and therefore has successfully staved off degradation [Credit: Rob Wallace/WCS]
The study is a reality check for nations striving to meet commitments under the Convention on Biological Diversity (CBD) to halt biodiversity loss through protected area creation. Since 1992, the global extent of protected areas has roughly doubled in size; more than 202,000 cover more than 15 percent of the world's terrestrial area, with a goal of at least 17 percent coverage by 2020.
Though management objectives differ, ranging from strict biodiversity conservation areas to zones permitting certain human activities and sustainable resource extraction, the primary goal of all protected areas is to conserve nature.
The authors looked at global "Human Footprint" maps to make their assessment which shows that 32.8 percent of protected land is highly degraded. For protected areas created before the CBD was ratified 1992, 55 percent have since experienced human pressure increases. The authors warn that CBD goals will be severely undermined if widespread human pressure continues inside protected areas.
Said the paper's lead author, Kendall Jones of University of Queensland: "A well-run protected area network is essential in saving species. If we allow our protected area network to be degraded there is a no doubt biodiversity losses will be exacerbated."
The study shows that governments are overestimating the space available for nature inside protected areas. Governments are claiming these places are protected for the sake of nature when in reality they aren't. It is a major reason why biodiversity is still in catastrophic decline, despite more and more land being 'protected'.
However, the authors are not suggesting that high pressure protected areas be de-gazetted or defunded. To the contrary, it is crucial that nations recognize the profound conservation gains that can be realized by upgrading and restoring degraded protected areas while respecting the needs of local people.
The Good News
The most impacted protected areas were found in Asia, Europe, and Africa in places with massive human populations. But the study did find some good news: protected areas with strict biodiversity conservation objectives are subject to significantly lower levels of human pressure.
Some of these least impacted protected areas include Keo Seima Wildlife Sanctuary in Cambodia, Madidi National Park in Bolivia, and Yasuni Biosphere Reserve in Ecuador - places where WCS has made considerable conservation investments and therefore has successfully staved off degradation.
Said Professor James Watson of WCS and University of Queensland, and the study's senior author: "We know protected areas work - when well-funded, well-managed and well placed, they are extremely effective in halting the threats that cause biodiversity loss and ensure species return from the brink of extinction. There are also many protected areas that are still in good condition and protect the last strongholds of endangered species worldwide. The challenge is to improve the management of those protected areas that are most valuable for nature conservation to ensure they safeguard it."
Protected areas are at the core of WCS's conservation strategy, as these are areas that are most effective at protecting natural ecosystems and their complement of biodiversity and ecosystem services - over 80 percent of WCS's site-based field work takes place within or around protected areas. When well-managed (through sound enforcement, monitoring, clear boundaries) and funded appropriately, protected areas are effective in reducing the loss of natural habitat, and sustaining wildlife populations.
Said Watson: "Most importantly we've got to recognize that these jewels in the crown need support- there are some protected areas that are safeguarding nature and that still haven't got any evidence of human encroachment in them. We must ensure these values are maintained."
Limiting global warming to 1.5°C would save the vast majority of the world's plant and animal species from climate change - according to new research led by the University of East Anglia.
The American pika is considered an indicator species for detecting ecological effects of climate change in mountainous regions [Credits: NPS]
A new report published in Science reveals that limiting warming to the ultimate goal of the Paris Agreement would avoid half the risks associated with warming of 2°C for plants and animals, and two thirds of the risks for insects.
Species across the globe would benefit - but particularly those in Southern Africa, the Amazon, Europe and Australia.
Reducing the risk to insects is particularly important, the team say, because they are so vital for 'ecosystem services' such as pollinating crops and flowers, and being part of the food chain for other birds and animals.
Previous research focused on quantifying the benefits of limiting warming to 2°C above pre-industrial times - the upper limit for temperature as set out in the Paris Agreement - and did not look at insects.
This is the first study to explore how limiting warming to 1.5°C would benefit species globally.
Researchers at UEA and James Cook University in Australia studied some 115,000 species including 31,000 insects, 8,000 birds, 1,700 mammals, 1,800 reptiles, 1,000 amphibians and 71,000 plants in this, the largest scale study of its kind.
Lead researcher Prof Rachel Warren, from the Tyndall Centre for Climate Change Research at UEA, said: "We wanted to see how different projected climate futures caused areas to become climatically unsuitable for the species living there.
"We measured the risks to biodiversity by counting the number of species projected to lose more than half their geographic range due to climate change.
"We found that achieving the ultimate goal of the Paris Agreement, to limit warming to 1.5°C above pre-industrial levels, would reap enormous benefits for biodiversity - much more so than limiting warming to 2°C.
"Insects are particularly sensitive to climate change. At 2°C warming, 18 per cent of the 31,000 insects we studied are projected to lose more than half their range.
"This is reduced to 6 per cent at 1.5°C. But even at 1.5°C, some species lose larger proportions of their range.
"The current global warming trajectory, if countries meet their international pledges to reduce CO2, is around 3°C. In this case, almost 50 per cent of insects would lose half their range.
"This is really important because insects are vital to ecosystems and for humans. They pollinate crops and flowers, they provide food for higher-level organisms, they break down detritus, they maintain a balance in ecosystems by eating the leaves of plants, and they help recycle nutrients in the soil.
"We found that the three major groups of insects responsible for pollination are particularly sensitive to warming.
"If temperatures rise by 3°C, ecosystem services provided by insects would be greatly reduced. Other research has already shown that insects are already in decline for other reasons, and this research shows that climate change would really compound the problem."
The study includes the ability of species to relocate to more suitable locations as the world warms. Birds, mammals and butterflies have the greatest ability to disperse. The dispersal means that a small number of species can gain in range by 2100.
Prof Warren added: "If warming is limited to 1.5°C by 2100 then more species can keep up or even gain in range, whereas if warming reached 2°C by 2100 many species cannot keep up and far more species lose large parts of their range."
Co-author Dr Jeff Price, also from UEA, added: "Examples of animals to really benefit from limiting warming to 1.5 include the critically endangered Black Rhinoceros, which is already highly threatened by poaching and habitat loss.
"There are also species which have been important in evolutionary theory and studied since the time of Charles Darwin, which would benefit from limiting warming to 1.5°C. These include Darwin's Finches of the Galapagos, such as the Large Ground Finch."
A new study, by 17 conservation scientists and environmental scholars, say the exact location of protective wild spaces is just as vital as committing to set these areas aside.
Polar bears are listed as a species of 'special concern' in Canada. Their numbers are declining from the combination of losing habitat and feeding opportunities (related to climate change) [Credit: Evan Richardson]
"Where Canada protects land is a significant decision," says UBC Okanagan researcher Laura Coristine, the study's lead author. "We wouldn't build a school in the highest traffic density area in a city--especially if few children live there. Selecting a site for a protected area similarly needs to guard against current threats to species and safeguard biodiversity into the future."
The research provides a first-ever framework to identify geographical hotspots that have the ecological potential to protect wild places and species from biodiversity loss associated with the global extinction crisis. The study, published in the journal Facets, uses five key ecological principles to guide the creation of the next generation of Canada's protected areas: preserve habitat for species at risk, represent Canada's diverse ecosystems, conserve remaining wilderness, ensure landscape connectivity, and protect areas that are more resilient to climate changes.
"Canada is a country rich and diverse in natural beauty, wildlife and resources," says Coristine. "As one of the largest countries in the world, Canada's commitment to protect 17 per cent of our land and inland water areas by 2020 is of global consequence. However, the Canadian government currently has no systematic, scientific way of accomplishing this goal to maximize conservation benefits."
Coristine is a Liber Ero postdoctoral researcher at UBC's Okanagan campus. She works out of the Wildlife Restoration Ecology research lab with Assistant Professor Adam T. Ford, who teaches biology in the Irving K. Barber School of Arts and Sciences.
"The world's wildlife is in rapid decline," says Ford, a Canada Research Chair in Wildlife Restoration Ecology. "Decisions about where land is protected and the extent of protection are of paramount importance."
Iconic Canadian species, like the boreal woodland caribou are threatened with extinction due to habitat loss, climate change, and loss of connectivity through their migratory routes [Credit: Jean Polfus]
Canada and 167 other countries are signatories to the international Convention on Biological Diversity, which pledges to reverse trends in species decline. Increasing the amount of protected lands is one way to do this.
"The framework provides a first step in the broader process of protected area decision-making and is intended to help identify the best ecological opportunities to protect Canada's rich natural heritage," explains Ford.
"Our research brings into focus the tough choices that need to be made--do we protect species at risk or pristine environments? Do we focus on the present day or ensure connectivity in a changing world?" says study co-author, Sally Otto, at UBC's Vancouver campus. "Or, as presented in our paper, do we strive to balance each of these needs?"
The paper states that Canada, a diverse land with 194 unique ecoregions, is home to much of the world's remaining intact wilderness. But most of this country's at-risk species live in the highly-populated south. Hundreds of bird, mammal and fish species have declined in population--in many cases due to habitat loss--and more than 735 species are at risk of extinction. Because climate change is causing additional problems, the report stresses the importance of connecting areas for migration while also protecting areas that are more resilient to climate change.
"Now is a critical time for the country to decide what is it that we most want to protect," says Coristine. "What we choose not to protect, we risk losing; what we protect remains a legacy for the future."
NUS ecologists have developed improved methods for estimating biodiversity loss from habitat-clearing activities, to aid conservation planning.
Natural habitats across the world are increasingly being cleared and fragmented by human activity. This photo shows a tropical forest in Sabah, Malaysia that has been cleared and fragmented to make way for oil palm plantations [Credit: R. Chisholm]
How many species are lost when a forest is cleared? This classic ecological question dates back to 1921, when Olof ARRHENIUS published his power-law species–area formula predicting species richness from habitat area. This formula can also be used to calculate how many species are lost when a habitat area shrinks. But Arrhenius’ formula assumes that habitat area is the only spatial variable of importance for species richness; it ignores the spatial pattern of habitat fragmentation. This is equivalent to assuming that the number of species persisting in Singapore’s 23 km2 of fragmented remnant forests is the same as it would be if the forest were one contiguous block. Realistic estimates of species richness and species loss require habitat fragmentation to be incorporated into the species–area formulas, but this has proven challenging.
A research team led by Prof Ryan CHISHOLM from Department of Biological Sciences, NUS have developed efficient mathematical formulas that incorporate the effect of habitat fragmentation to provide better estimates of species loss from land-clearing activities. The team achieved this by using novel rescaling techniques inspired by coalescence methods used in population genetics. The formulas permit rapid estimation of the upper (contiguous land clearing; minimum fragmentation) and lower (random land clearing; maximum fragmentation) bounds on species loss, which would otherwise require a large amount of computational effort if done through numerical simulations. Applying the new formulas to case studies, they found that immediate species loss is fairly insensitive to the exact pattern of habitat fragmentation at small scales (e.g. several hectares) but highly sensitive at larger scales (e.g. the Amazon rainforest). These tools and findings can help guide land planners in their biodiversity conservation efforts.
Prof Chisholm said, “When we applied the new formulas to estimate tree species loss in Singapore over the last 200 years, we found that the lower bound from our formulas, which assumes maximum fragmentation, was close to independent estimates of tree species loss from Singapore Botanic Gardens herbarium data. We speculate that this is because the forest in Singapore is quite fragmented, and so more tree species persist here (at least in the medium term) than would if the remaining forest were one contiguous block.”
While the new formulas published by the researchers allow for estimation of immediate species loss from habitat clearing, the researchers are now turning their attention to longer-term problems. In particular, they are studying the phenomenon of “extinction debt”, whereby species continue to be lost in the following decades or centuries after their habitat has been cleared.
The evolution of wild species, adapting them to human management practices, can cause localised extinctions when those practices rapidly change. And in a new study published in Nature, Professors Michael C. Singer and Camille Parmesan have used more than 30 years of research to fully document an example of this process.
Edith's checkerspot butterfly (Euphydryas editha) on a narrow-leaved plantain (Plantago lanceolata) [Credit: Michael C. Singer/University of Plymouth]
A large, isolated population of a North American butterfly evolved complete dependence on an introduced European weed to the point where the continued existence of the butterfly depended on the plant's availability. The insects then became locally extinct when humans effectively eliminated that availability, confirming a prediction made by the same authors in a 1993 Nature paper.
Thus the advent of cattle ranching more than 100 years ago set an eco-evolutionary trap that the insects obligingly fell into, and the trap was sprung when humans suddenly removed the cattle, withdrawing their 'gift', and driving the butterflies to extinction.
European conservation biologists have long believed this to be the process underlying many local extinctions across Europe, and this study provides the first hard evidence of the process in action in real time. It also foreshadows an increasing importance of maintaining historical land use practices, including cattle ranching, as conservation measures in North America.
The authors, affiliated to the University of Plymouth, the University of Texas at Austin and CNRS Moulis, have spent more than three decades studying changes in the diet of Edith's checkerspot (Euphydryas editha) in a spring-fed meadow surrounded by semi-desert sagebrush and pine forest on a family-run ranch in Nevada.
In particular, the authors assessed the impact of narrow-leaved plantain (Plantago lanceolata), which was introduced to the USA in hay brought from Europe and flourished under cattle-grazing, probably arriving in Nevada more than 100 years ago.
As soon as the butterflies encountered the plantain, their caterpillars survived better on it than on their traditional host, Blue-Eyed Mary (Collinsia parviflora), causing the adults to evolve preference for laying eggs on the plantain. By the mid-2000s, they were 100% reliant on the plantain and the Collinsia had been abandoned.
However, within three years of the ranch's cattle being removed due to financial pressures, the butterflies became locally extinct as the grasses around their favoured new host were no longer grazed, and the plantains became embedded in those grasses, cooling the micro-environment. The Collinsia was unaffected by removal of cattle, so if the butterflies had not evolved so rapidly in response to the introduction of the plantain, they would most likely have survived.
Around five years after the extinction, Edith's checkerspots recolonized the meadow. Since they were all found feeding on Collinsia, the original host plant, scientists believe these colonists to be a new population, and that the lineage which had called the ranch home for several decades no longer exists.
They say the results are similar to that seen in British species such as the large blue butterfly, which went extinct across southern England following a reduction of grazing by both rabbits and sheep. Once this process was understood, the butterflies could be successfully re-introduced.
Professor Singer, who has been studying the diet of Edith's checkerspot for more than 50 years and led the current study, said: "This is a clear example of how humans are able to change habitats faster than even rapidly-evolving species can change their behaviour. This cannot be not an isolated phenomenon, so unless we become aware of the potential consequences of such actions we will continue to inadvertently cause population extinctions of native species, without recognizing what we are doing. Species-level extinctions are possible when human activities are synchronized across wide areas."
Professor Parmesan, a lead contributor to the Intergovernmental Panel on Climate Change which was awarded the Nobel Peace Prize in 2007, said the study had potentially wider implications beyond the scope of changes to farming practices.
She added: "Climate warming is another form of anthropogenic change that is occurring faster than past natural changes, and is likely to cause problems for species whose evolution is unable to keep pace. If climate change were natural, it is likely that many wild species would be able to adapt, both through current evolution and through flexible changes in behaviour and life history. But human-driven climate change is occurring at a much faster rate than most past major climatic shifts. Ecologists have long been arguing that this is likely to lead to more extinctions than have happened with past climatic changes and this study supports the arguments that rapid climate change will prove detrimental to biodiversity both in the short and long term."
Sporting a bright red-and-yellow dewlap under its chin, the color-changing Bahamian anole lizard is a popular exotic pet. This wily anole has escaped captivity on enough occasions to successfully invade large areas across the Western Hemisphere. At first glance, this suggests that the anole is well-suited to adapt to a changing climate. But a new study led by a Smithsonian researcher, suggests that may not be the case.
A Bahamian anole lizard (Anolis sagrei) perches in its native terrain in the Bahamas [Credit: Michael Logan]
Michael Logan, post-doctoral fellow at the Smithsonian Tropical Research Institute in Panama, studies the brown anole in its home range in the Bahamas. His most recent study shows that the anole's genetic makeup is surprisingly ill-suited to future climate scenarios. The anole is therefore unlikely to adapt fast enough to keep pace with current rates of environmental change.
The findings, published in Proceedings of the Royal Society B, have important implications for the future of cold-blooded species (such as other reptiles, amphibians and fish), especially since rapid evolution is considered a key way for many of these species to survive a global increase in temperatures.
"Brown anoles have huge population sizes and therefore should have loads of genetic variation in most traits, permitting rapid adaptation," Logan said. "Instead, we found that genetic variation in several traits that are critical under climate change is basically zero."
Brown anoles are ectotherms: they rely on the temperature of the environment to control their body heat. When they are too cold, they shuffle off to a sunny spot and soak up heat. When they are too hot, they seek shade or cooler spots. Maintaining an optimal body temperature is a basic component for success at essentials of life--moving, eating and reproducing.
For the study, Logan and colleagues captured brown anoles from two different, isolated habitats in the Bahamas. One is relatively cool and forested; the other is a hot, sun-soaked peninsula. In laboratory conditions, they raised hundreds of offspring from these two populations and, after they reached adulthood, challenged them in some simple trials.
To evaluate physical performance at different body temperatures, they used a high-speed camera to film the lizards as they ran across a wooden dowel rod. To better understand how they behaved when exposed to environments of different temperatures, they used gel packs and heating lamps to create an environment that ranged from 20 degrees C to 48 degrees C and recorded where the lizards moved and how they adjusted to changes in temperature. To understand the offspring's inherited traits -- and thus evaluate their potential to evolve -- they ran a series of analyses.
The results surprised across the board, especially since the different lizard populations had long been isolated in highly contrasting environments. While the researchers found some evidence that the populations were adapted to their local environments, genetic results suggested the lizards have little built-in capacity to inherit traits that would allow them to evolve apace with climate change. One possible explanation is that strong selection pressure in the past, which caused them to be adapted to different environments in the first place, eliminated future genetic variation that may be required.
"If genetic variation in thermal traits is rock bottom for a species like the brown anole that has huge population sizes and a super-wide geographic distribution," asks Logan, "what will it be for most other species that typically have much smaller population sizes and live relatively isolated, specialized lifestyles?"
Occurrence probability of three lemur species in tropical dry forest increases with fragment size but can increase or decrease with fragment isolation depending on the species, according to a study published in the open-access journal PLOS ONE by Travis Steffens and Shawn Lehman from University of Toronto, Canada.
A common brown lemur (Eulemur fulvus) [Credit: Travis S. Steffens]
Lemurs live only in Madagascar, and nearly all species are at risk of extinction primarily due to habitat loss and fragmentation. The independent effects of forest loss and of forest fragmentation are not well understood, however. To assess the relative impact of these threats, Steffens and Lehman surveyed lemurs in fragmented dry deciduous forest in Ankarafantsika National Park, Madagascar between June and November 2011, observing six lemur species in 42 forest fragments. The researchers then used incidence function models to examine whether the lemurs formed metapopulations, spatially-separated populations within a species, in a fragmented landscape and under different forest fragmentation conditions.
In their simulations, the researchers found that three of the lemur species did form metapopulations in forest fragments. Within these metapopulations, occurrence was affected by both forest fragment size and isolation. However, fragment size appeared to be more important in determining lemur occurrence, with larger forest patches being associated with increased lemur occurrence.
Madagascan forests are becoming increasingly fragmented, and this work helps to clarify how lemurs respond. It appears to be helpful to use a metapopulation approach when studying lemurs, and maintenance of habitat area may be crucial to maintaining populations in this fragmented landscape.
"Some lemur species are capable of tolerating high levels of habitat loss and fragmentation by forming metapopulations," says Travis Steffens. "In metapopulations occurrence probability is positively related to habitat area for each species while isolation has species-specific positive, negative and neutral impacts on occurrence probability."
At first glance, the Baltic Sea seems to be rather uninteresting for scientists working on global ocean topics. It is comparatively shallow, has a low salinity and only a very narrow connection to the North Atlantic. This impression is, however, deceiving. In the current issue of the international journal Science Advances, 26 authors from 21 scientific institutions in seven countries appeal to the greater scientific community and policy makers to use the Baltic Sea Region as a model for coming changes in the World Ocean. "This unique sea of brackish water can serve as a kind of time machine that allows us to better estimate future global changes," says Prof. Thorsten Reusch from the GEOMAR Helmholtz Center for Ocean Research Kiel, one of the lead authors of the article.
The Baltic Sea can be regarded as a model area for changes in the world ocean [Credit: Christoph Kersten, GEOMAR]
The scientists argue that changes that are only expected for the future in the global ocean can already be observed in the Baltic today. "This is because the small volume of water and slow water exchange with the open ocean, behaves like an amplifier, allowing many processes and interactions to occur at a faster pace", emphasizes Dr. Jan Dierking from GEOMAR, who initiated the study together with Prof. Reusch.
As examples, the oceans have warmed by an average of 0.5°C over the past 30 years, while in the same period, time-series measurements in the Baltic Sea have recorded warming of around 1.5°C. Likewise, there are large oxygen-free zones in the deep areas of the Baltic Sea, which have increased tenfold over the past century; and the pH--a measure of ocean acidification--of Baltic waters regularly reaches values that are expected in other ocean areas only in the next century.
Water sampler on RV LITTORINA in the Baltic [Credit: GEOMAR]
On the one hand, these extremes are caused by the particular basin topography of the Baltic Sea. On the other hand, intensive use by humans continues to accelerate negative changes. Nine countries border on the Baltic Sea directly and all are highly industrialized, with densely populated coastal regions. Moreover, intensive agriculture in the interior ensures high nutrient runoff, while equally intensive fisheries puts pressure on the pelagic food-web.
But it's not all doom and gloom. The Baltic Sea is one of the best-surveyed seas on Earth. Scientific observation and monitoring of physical and biological processes began around 1900. There is a strong tradition in scientific co-operation among many countries surrounding the Baltic, culminating in the implementation of the joint Baltic Sea research and development programme BONUS of the European Union, a dedicated macro-regional research agenda and funding scheme that also enabled the present study. These data provide a sound basis for science-based resource management--"on a level accomplished in only a few regions of the world," emphasizes Professor Reusch.
Collection of water samples on RV LITTORINA [Credit: GEOMAR]
Among the management success stories: the bordering countries have managed to significantly reduce nutrient inputs since the 1980s, to reverse the decline of large predators, and to curb overfishing. This has been achieved through the binding agreements within the framework of the European Union, but also thanks to the ambitious goals of the Baltic Sea Action Plan (BSAP), which included Russia, even before the end of the Cold War. In fisheries, the protection of capture fisheries, marine mammals and bird populations among the perimeter countries have led to measurable improvements of existing stocks.
"Overfishing, warming, acidification, pollution, eutrophication, loss of oxygen, intensive use of coasts--all these are phenomena that we observe around the globe. Because they have been particularly drastic in the Baltic, but also because some key problems were successfully addressed, the region can, for good and for bad, tell us what to expect and how to respond to the challenges of the future," Prof. Reusch concludes, "The Baltic Sea, as a model region, can contribute to achieving the United Nation's Sustainable Development Goal 14--the conservation and sustainable use of the oceans, seas and marine resources."
The Earth — with its myriad shifting atmospheric, oceanic, land and ice components — presents an extraordinarily complex system to simulate using computer models.
Argonne scientists helped create a comprehensive new model that draws on supercomputers to simulate how various aspects of the Earth - its atmosphere, oceans, land, ice - move [Credit: E3SM.org]
But a new Earth modeling system, the Energy Exascale Earth System Model (E3SM), is now able to capture and simulate all these components together. Released on April 23, after four years of development, E3SM features weather-scale resolution — i.e., enough detail to capture fronts, storms and hurricanes — and uses advanced computers to simulate aspects of the Earth’s variability. The system can help researchers anticipate decadal-scale changes that could influence the U.S. energy sector in years to come.
“With this new system, we’ll be able to more realistically simulate the present, which gives us more confidence to simulate the future.” — David Bader, computational scientist at Lawrence Livermore National Laboratory and overall E3SM project lead.
The E3SM project is supported by the U.S. Department of Energy’s (DOE) Office of Biological and Environmental Research. “One of E3SM’s purposes is to help ensure that DOE’s climate mission can be met — including on future exascale systems,” said Robert Jacob, a computational climate scientist in the Environmental Science division of DOE’s Argonne National Laboratory and one of 15 project co-leaders.
To support this mission, the project’s goal is to develop an Earth system model that increases prediction reliability. This objective has historically been limited by constraints in computing technologies and uncertainties in theory and observations. Enhancing prediction reliability requires advances on two frontiers: (1) improved simulation of Earth system processes by developing new models of physical processes, increasing model resolution and enhancing computational performance; and (2) representing the two-way interactions between human activities and natural processes more realistically, especially where these interactions affect U.S. energy needs.
“This model adds a much more complete representation between interactions of the energy system and the Earth system,” said David Bader, a computational scientist at Lawrence Livermore National Laboratory and overall E3SM project lead. “With this new system, we’ll be able to more realistically simulate the present, which gives us more confidence to simulate the future.”
The long view
Simulating the Earth involves solving approximations of physical, chemical and biological governing equations on spatial grids at the highest resolutions possible.
In fact, increasing the number of Earth-system days simulated per day of computing time at varying levels of resolution is so important that it is a prerequisite for achieving the E3SM project goal. The new release can simulate 10 years of the Earth system in one day at low resolution or one year of the Earth system at high resolution in one day (a sample movie is available at the project website). The goal is for E3SM to support simulation of five years of the Earth system on a single computing day at its highest possible resolution by 2021.
This objective underscores the project’s heavy emphasis on both performance and infrastructure — two key areas of strength for Argonne. “Our researchers have been active in ensuring that the model performs well with many threads,” said Jacob, who will lead the infrastructure group in Phase II, which — with E3SM’s initial release — starts on July 1. Singling out the threading expertise of performance engineer Azamat Mametjanov of Argonne’s Mathematics and Computer Science division, Jacob continued: “We’ve been running and testing on Theta, our new 10-petaflop system at Argonne’s Leadership Computing Facility, and will conduct some of the high-res simulations on that platform.”
Researchers using the E3SM can employ variable resolution on all model components (atmosphere, ocean, land, ice), allowing them to focus computing power on fine-scale processes in different regions. The software uses advanced mesh-designs that smoothly taper the grid-scale from the coarser outer region to the more refined region.
Adapting for exascale
E3SM’s developers — more than 100 scientists and software engineers — have a longer-term aim: to use the exascale machines that the DOE Advanced Scientific Computing Research Office expects to procure over the next five years. Thus, E3SM development is proceeding in tandem with the Exascale Computing Initiative. (Exascale refers to a computing system capable of carrying out a billion [1018] calculations per second — a thousand-fold increase in performance over the most advanced computers from a decade ago.)
Another key focus will be on software engineering, which includes all of the processes for developing the model; designing the tests; and developing the required infrastructure, including input/output libraries and software for coupling the models. E3SM uses Argonne’s Model Coupling Toolkit (MCT), as do other leading climate models (e.g., Community Earth System Model [CESM]) to couple the atmosphere, ocean and other submodels. (A new version of MCT [2.10] was released along with E3SM.)
Additional Argonne-specific contributions in Phase II will center on:
- Crop modeling: Efforts will focus on better emulating crops such as corn, wheat and soybeans, which will improve simulated influences of crops on carbon, nutrient, energy and water cycles, as well as capturing the implications of human-Earth system interactions
- Dust and aerosols: These play a major role in the atmosphere, radiation and clouds, as well as various chemical cycles.
Collaboration among – and beyond – national laboratories
The E3SM project has involved researchers at multiple DOE laboratories including Argonne, Brookhaven, Lawrence Livermore, Lawrence Berkeley, Los Alamos, Oak Ridge, Pacific Northwest and Sandia national laboratories, as well as several universities.
The project also benefits from collaboration within DOE, including with the Exascale Computing Project and programs in Scientific Discovery through Advanced Computing, Climate Model Development and Validation, Atmospheric Radiation Measurement, Program for Climate Model Diagnosis and Intercomparison, International Land Model Benchmarking Project, Community Earth System Model and Next-Generation Ecosystem Experiments for the Arctic and the Tropics.
