From EarthSky and Eos: “Volcanic Eruption Creates Temporary Islands of Pumice”

From EarthSky

From AGU

From Eos

6 September 2019
Katherine Kornei, Eos
Eleanor Imster, EarthSky

Sailing through rocks is anything but quiet. Last month, vessels in the South Pacific clinked and clanked their way through pumice spewed out from an undersea volcano. These temporary islands of volcanic rock, shaped and propelled by ocean currents, wind, and waves, provide a literal toehold for marine life like barnacles, coral, macroalgae, and mollusks.

Last month, rafts of pumice, spewed from an undersea volcano and spanning an area about the size of Washington, D.C., appeared in the South Pacific. Satellite image of a pumice raft floating near the Kingdom of Tonga. Image via NASA Earth Observatory.

In early August, an unnamed volcano near the Kingdom of Tonga erupted roughly 40 meters underwater. The eruption sent pieces of gray pumice—porous rock filled with gas bubbles—floating to the surface. This volcanic debris, some fragments as large as beach balls, then aggregated into pumice “rafts” spanning roughly 200 square kilometers.

August 13, 2019. See detail below. Image via NASA Earth Observatory.

Detail of above image, taken August 13, 2019. Image via NASA Earth Observatory.

Several sailing crews have encountered the rocks.

“We were in a large area surrounded as far as the eye could see,” said Rachel Mackie, the purser and chef of Olive, a private vessel that sailed into a raft on 9 August near Late Island. There was a strong smell of sulfur, said Mackie, and Olive took a beating. “When the larger rocks hit the steel hull, it reverberated.”

Several sailing crews have encountered the rocks.

“We were in a large area surrounded as far as the eye could see,” said Rachel Mackie, the purser and chef of Olive, a private vessel that sailed into a raft on 9 August near Late Island. There was a strong smell of sulfur, said Mackie, and Olive took a beating. “When the larger rocks hit the steel hull, it reverberated.”

Pumice rafts aren’t that common, said Martin Jutzeler, a volcanologist at the University of Tasmania in Hobart. “We see about two per decade.”

Not all undersea eruptions produce them, but the rafts that do form tend to stick around. They can last for months or years until the pumice abrades itself into dust or finally sinks. And floating pumice can traverse long distances—when the same unnamed volcano near Tonga erupted in 2001, the pumice raft it created eventually arrived in Queensland, Australia, said Jutzeler.

These transient, movable islands play an important role in marine ecosystems, scientists agree. Barnacles, coral, and macroalgae have all been found clinging to pumice, riding the waves en route to a new home.

“It’s a perfect little substrate,” said Jutzeler.

In 2012, Scott Bryan, a geologist at the Queensland University of Technology in Australia, and his colleagues showed that pumice rafts can significantly increase the dispersal of marine organisms. Bryan and his team found that more than 80 species traveled thousands of kilometers aboard pumice following the 2006 eruption of Home Reef Volcano in Tonga. “Pumice is an extremely effective rafting agent that can…connect isolated shallow marine and coastal ecosystems,” the researchers wrote in PLoS ONE.

The long-distance journeys of pumice rafts are “definitely a way to get organisms to disperse widely,” said Erik Klemetti, a volcanologist at Denison University in Granville, Ohio, not involved in the research. But the idea that the stowaways aboard pumice rafts might replenish the Great Barrier Reef’s corals is wishful thinking, said Klemetti. “That’s probably an oversell.”

Jutzeler and his colleagues are planning to study pumice from last month’s eruption. They’ve been in touch with several vessels that passed through the rafts, and they’ve arranged to analyze some of the rocks. (But the samples they’ve been promised are currently stuck in transit in Fiji, said Jutzeler.)

By analyzing the chemistry of the pumice, Jutzeler and his colleagues hope to learn about the properties of the underwater volcanic eruption. For instance, was it eruptive or effusive?

Studying the rocks’ surfaces will also reveal how quickly they’re being abraded, which will shed light on how rapidly volcanic dust is being deposited into the ocean. That’s important because some plankton feed on this volcanic debris, which can result in phytoplankton blooms, said Jutzeler.

Jutzeler and other researchers are keeping a close watch on how the rafts are moving. Satellite imagery—from Terra, Aqua, Sentinel, and Landsat satellites, for instance—provides nearly daily updates. Ocean currents, wind, and waves sculpt and power the rafts, which now number in the hundreds.

NASA Terra satellite

ESA Sentinels (Copernicus)

NASA/Landsat 8

They’ll likely arrive in Fiji in a few weeks, Jutzeler predicts.

See the full article here .

five-ways-keep-your-child-safe-school-shootings

Please help promote STEM in your local schools.

Stem Education Coalition

Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. “Being an EarthSky editor is like hosting a big global party for cool nature-lovers,” she says.

From UC Riverside: “Guppies teach us why evolution happens”

From UC Riverside

September 17, 2019
Jules Bernstein

Guppies, a perennial pet store favorite, have helped a UC Riverside scientist unlock a key question about evolution:

Do animals evolve in response to the risk of being eaten, or to the environment that they create in the absence of predators? Turns out, it’s the latter.

Guppies swim near the Quare River in Trinidad, where conditions are right for observation with and without predators. (David Reznick/UCR)

David Reznick, a professor of biology at UC Riverside, explained that in the wild, guppies can migrate over waterfalls and rapids to places where most predators can’t follow them. Once they arrive in safer terrain, Reznick’s previous research shows they evolve rapidly, becoming genetically distinct from their ancestors.

“We already knew that they evolved quickly, but what we didn’t yet understand was why,” Reznick said. In a new paper published in American Naturalist, Reznick and his co-authors explain the reason the tiny fish evolve so quickly in safer waters.

To answer their questions, the scientists traveled to Trinidad, guppies’ native habitat, and conducted an experiment. They moved guppies from areas in streams where predators were plentiful to areas where predators were mostly absent. Over the course of four years, they studied how the introduced guppies changed in comparison to ones from where they originated.

“If guppies evolve because they aren’t at risk of becoming food for other fish, then evolution should be visible right away,” Reznick said. “However, if in the absence of predators they become abundant and deplete the environment of food, then there will be a lag in detectable changes.”

Guppies from all four streams were marked so they could be tracked over the course of four years. The scientists tracked the males, which tend to live about five months. They looked at the fishes’ age and size at maturity, which are key traits affecting population growth.

They also tracked how the environment changed as the guppy populations expanded, focusing on the abundance of food such as algae and insects, as well as the presence of other nonpredator fish.

They found a two-to-three-year lag between when guppies were introduced and when males evolved, suggesting the second hypothesis was correct; guppies were first changing their new environments, and then as a result, they turned out to be changing themselves.

“The speed of evolution makes it possible to study how it happens,” Reznick said. “The new news is that organisms can shape their own evolution by changing their environment.”

One of Reznick’s current projects includes applying these concepts to questions about human evolution.

“Unlike guppies and other organisms, human population density seems to increase without apparent limit, which increases our impact on our environment and on ourselves,” he said.

Co-authors on this study included Ron Basser, a former doctoral student at UC Riverside and now assistant professor at Williams College; Joe Travis at Florida State University; Corey Handelsman, Cameron Ghalambor, Emily Ruell, and Julian Torres-Dowdall from Colorado State University; Tim Coulson and Tomos Potter of Oxford University, and Paul Bentzen of Dalhousie University in Canada.

See the full article here .

five-ways-keep-your-child-safe-school-shootings

Please help promote STEM in your local schools.

Stem Education Coalition

The University of California, Riverside is one of 10 universities within the prestigious University of California system, and the only UC located in Inland Southern California.

Widely recognized as one of the most ethnically diverse research universities in the nation, UCR’s current enrollment is more than 21,000 students, with a goal of 25,000 students by 2020. The campus is in the midst of a tremendous growth spurt with new and remodeled facilities coming on-line on a regular basis.

We are located approximately 50 miles east of downtown Los Angeles. UCR is also within easy driving distance of dozens of major cultural and recreational sites, as well as desert, mountain and coastal destinations.

From European Space Agency: “Using a data cube to assess changes in the Earth system”

From European Space Agency

16 September 2019

Changing Arctic productivity
Derived from FLUXCOM land–atmosphere energy fluxes, hosted on the Earth System Data Lab
In parts of the Arctic tundra, temperatures are increasing rapidly as a result of climate change. This has resulted in complex changes in plant communities, with satellite data showing that some parts of the Arctic are ‘greening’ whilst other areas are said to be ‘browning’. Using the Earth System Data Lab, scientists are looking at components such as rock or soil types to understand changes in plant productivity in the Arctic, beyond just temperature. The image shows changes in mean maximum gross primary productivity across five years between 2001–2005 and 2011–2015 at high latitudes (>60°N). Notable changes in gross primary productivity are evident including large increases in northern Canada, and decreases in parts of Alaska and Siberia, highlighting the heterogeneous pattern of productivity change over time.

Researchers all over the world have a wealth of satellite data at their fingertips to understand global change, but turning a multitude of different data into actual information can pose a challenge. Using examples of Arctic greening and drought, scientists at ESA’s ɸ-week showed how the Earth System Data Lab is making this task much easier.

ESA’s Earth System Data Lab is a new virtual lab to access a wide array of Earth observations across space, time and variables. It consists of two elements: the data cube and an interface to execute different analyses on the data cube.

Last year, ESA put out a call – an Early Adopters Call – for young researchers to explore information from data streams produced by several international scientific teams to help shape the future of the Earth System Data Lab.

Some of these young researchers using the Earth System Data Lab were at ESA’s ɸ-week presenting their findings on, for example, Arctic greening and drought.

In parts of the Arctic tundra, temperatures are increasing rapidly as a result of climate change. This has resulted in complex changes in plant communities, with satellite data showing that some parts of the Arctic are ‘greening’ whilst other areas are said to be ‘browning’. Understanding changes at high latitudes is crucial as they could be used to predict changes in other places that haven’t yet warmed as much.

Oliver Baines, from the University of Nottingham in the UK, said, “The work I presented examines whether the inclusion of geodiversity components, such as rock or soil types, can improve our understanding of changes in plant productivity in the Arctic, beyond considering just temperature.

“Using the Earth System Data Lab, we have been able to examine these relationships to identify the role of abiotic nature at a much larger scale than before.”

By providing a set of pre-processed datasets all in one place, the virtual lab has made it easier to access, manipulate and analyse different variables including climate, gross primary productivity related to photosynthesis, aerosols and sea-surface temperatures.

Mr Baines continues, “The hope is that by including a wider variety of abiotic nature, our understanding of changes in the Arctic can be improved and, subsequently, that any future predictions of Arctic environmental change can be refined.”

The data cube can reveal where big anomalies occur. In the light of the last two summers when Europe was hit by unprecedented heatwaves, and this year’s devastating fires in the Amazon, the relevance of the work being carried out through the virtual lab becomes clear.

Miguel Mahecha, from the Max Planck Institute for Biogeochemistry in Germany, said, “Only if we succeed in putting these impacts into a global perspective, will we be able to objectively judge their impacts. And, even more importantly, understand and anticipate their impacts under future climate conditions.”

However, while the question of weather extremes is an issue, long-term change and climate change are a global concern.

“Large parts of South America, for example, have become less productive and drier over the past decade. But there is a need to understand if this is a real change or just decadal variability. And, the Earth System Data Lab is helping us with this research,” continued Mr Mahecha.

Another Early Adopter, Karina Winkler from the Karlsruhe Institute of Technology, Germany, is working on using reconstructed land-use data and multiple satellite-derived variables from the Earth System Data Lab. The objective of the project is to model biomass distribution by using deep learning – which shows the potential of reconstructing changes of above-ground biomass over time and at a global scale.

ESA’s ɸ-week gave researchers the unique opportunity to share and discuss their research and reflect on the value of this new data cube they have to hand.

See the full article here .

five-ways-keep-your-child-safe-school-shootings
Please help promote STEM in your local schools.

Stem Education Coalition

The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

From CSIROscope: “Saving baby turtles one nest at a time”

From CSIROscope

16 September 2019
Louise Jeckells

Every year thousands of sea turtles come to the beaches of the western Cape to nest. Photo by Gina Zimny

When baby sea turtles, or hatchlings, break free from their eggs they have to make a long and difficult journey to the ocean. These tiny newborns face a number of threats just trying to make it to the water’s edge. This running of the gauntlet is critical for their survival and the continuation of the species.

But before they even leave the nest they’re already under threat. Predators taking eggs from the nest is one of the most significant threats to marine turtles. Feral pigs, goannas and dingoes are disturbing turtle nests in parts of Queensland’s western Cape York Peninsula. Before our research scientist Dr Justin Perry and Indigenous rangers from Aak Puul Ngangtam (APN Cape York) started working in the area, there was 100 per cent predation on turtle nests. No baby turtles were reaching the ocean.

We’ve been working with the local community since 2008 to understand the impacts of feral animals on the ecological and economic values of northern Australia. Justin and his team focussed on a biocultural assessment to understand the impacts on turtles and to collaboratively design a solution with local people.

“This was a big problem and the management actions being applied weren’t working,” Justin said.

“The science and monitoring was separated from the management, and management was separated from the community.”

Turtles survey team on Cape York beach. Photo by Gina Zimny

Forging a pig plan together

“We brought together the regional bodies that were responsible for managing pigs and turtles to create the Northern Nest Project. This was when we started to look at the turtle problem in a holistic way,” Justin said.

The working group decided to tackle the problem using a targeted control method. They trialed a baiting system to target the specific pigs that were coming onto the beach and eating the eggs.

This control method was not popular with Traditional Owners as the effects on other species such as dingoes and birds were unknown. The scientists ran a very small-scale project, monitoring every bait station with cameras and providing regular reports. The efforts were rewarded. The following year there was a 100 per cent success rate for baby turtles hatching and reaching the ocean.

Turtle measurements are essential to improving our understanding. The data is collected at night. Photo by Gina Zimny

Specific predation plans

After this success, we (through the Northern Australia Environmental Resources Hub project) and APN funded a full-time researcher to patrol the beach during the turtle nesting season. This provided a complete overview of the predation events and turtle nesting habits across the year. Once the team started measuring the pig impacts, they could see the impact of other predators in the area.

Another Indigenous group had been using cages to stop feral pigs. But the aluminum cages were heavy and hard to manage. So Justin and his team decided to test the effectiveness of inexpensive and easy to carry garden mesh for protecting nests from predators. APN’s resident scientist, Gina Zimny, meshed hundreds of nests across the season. When the team tallied up the impact, it was clear that this method was only stopping a handful of predators. The mesh protected nests from hungry dingoes but only stopped around 10 per cent of goannas. And they were helpless against the destructive power of feral pigs.

Mesh protects turtle hatchlings from predation but still enables them to head for the ocean. Photo by Gina Zimny

Protecting the nests of marine turtles from raids by pigs, dingoes and goannas requires species-specific management strategies. To tackle this challenge, we designed an interactive dashboard that combined all the data that had been collected for the past four years. This way rangers could see how effective their management efforts had been.

On target

Justin said the most efficient way of controlling predation was linking the monitoring data with management.

“Everyone agreed that the value was getting more baby turtles into the ocean. And turtle experts had set a target of 70 per cent of nests hatching to maintain a healthy population.

“To hit this metric of success, we knew we had to apply an adaptive management process to the problem,” Justin said.

Cape York. Photo by Gina Zimny

“We’re working towards providing an immediate feedback loop on predation. The idea is to link an iPad application with a cloud server. Then when the rangers return every night, a summary dashboard updates and provides all the data required to react to the situation.

“It’s such a vast landscape so the only way to win is to tackle one small task at a time. Trying to control the entire pig population is not feasible. But targeting the egg-eating individuals can be done and we have shown that it works,” Justin said.

This year we are working on automating the data analysis and summaries so that rangers get to see what’s happening on their beaches in real-time. Having real-time data linked with planned management responses will close the adaptive management loop. And it will give the baby turtles the best chance of making it from nest to ocean.

See the full article here .

five-ways-keep-your-child-safe-school-shootings

Please help promote STEM in your local schools.

Stem Education Coalition

SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia

So what can we expect these new radio projects to discover? We have no idea, but history tells us that they are almost certain to deliver some major surprises.

Making these new discoveries may not be so simple. Gone are the days when astronomers could just notice something odd as they browse their tables and graphs.

Nowadays, astronomers are more likely to be distilling their answers from carefully-posed queries to databases containing petabytes of data. Human brains are just not up to the job of making unexpected discoveries in these circumstances, and instead we will need to develop “learning machines” to help us discover the unexpected.

With the right tools and careful insight, who knows what we might find.

CSIRO, the Commonwealth Scientific and Industrial Research Organisation, is Australia’s national science agency and one of the largest and most diverse research agencies in the world.

From University of North Carolina via EarthSky: “Why carbon dioxide has such outsized influence on Earth’s climate”

From University of North Carolina

via

EarthSky

September 16, 2019
Jason West

Carbon dioxide, CO2, makes up less than one-twentieth of 1% of Earth’s atmosphere. How does this relatively scarce gas control Earth’s thermostat?

I am often asked how carbon dioxide can have an important effect on global climate when its concentration is so small – just 0.041% of Earth’s atmosphere. And human activities are responsible for just 32% of that amount.

The ‘Keeling Curve,’ named for scientist Charles David Keeling, tracks the accumulation of carbon dioxide in Earth’s atmosphere, measured in parts per million. Image via Scripps Institution of Oceanography.

NASA Orbiting Carbon Observatory 2, NASA JPL-Caltech

Early greenhouse science

The scientists who first identified carbon dioxide’s importance for climate in the 1850s were also surprised by its influence. Working separately, John Tyndall in England and Eunice Foote in the United States found that carbon dioxide, water vapor and methane all absorbed heat, while more abundant gases did not.

Scientists had already calculated that the Earth was about 59 degrees Fahrenheit (33 degrees Celsius) warmer than it should be, given the amount of sunlight reaching its surface. The best explanation for that discrepancy was that the atmosphere retained heat to warm the planet.

Tyndall and Foote showed that nitrogen and oxygen, which together account for 99% of the atmosphere, had essentially no influence on Earth’s temperature because they did not absorb heat. Rather, they found that gases present in much smaller concentrations were entirely responsible for maintaining temperatures that made the Earth habitable, by trapping heat to create a natural greenhouse effect.

A blanket in the atmosphere

Earth constantly receives energy from the sun and radiates it back into space. For the planet’s temperature to remain constant, the net heat it receives from the sun must be balanced by outgoing heat that it gives off.

Since the sun is hot, it gives off energy in the form of shortwave radiation at mainly ultraviolet and visible wavelengths. Earth is much cooler, so it emits heat as infrared radiation, which has longer wavelengths.

The electromagnetic spectrum is the range of all types of EM radiation – energy that travels and spreads out as it goes. The sun is much hotter than the Earth, so it emits radiation at a higher energy level, which has a shorter wavelength. Image via NASA.

Carbon dioxide and other heat-trapping gases have molecular structures that enable them to absorb infrared radiation. The bonds between atoms in a molecule can vibrate in particular ways, like the pitch of a piano string. When the energy of a photon corresponds to the frequency of the molecule, it is absorbed and its energy transfers to the molecule.

Carbon dioxide and other heat-trapping gases have three or more atoms and frequencies that correspond to infrared radiation emitted by Earth. Oxygen and nitrogen, with just two atoms in their molecules, do not absorb infrared radiation.

Most incoming shortwave radiation from the sun passes through the atmosphere without being absorbed. But most outgoing infrared radiation is absorbed by heat-trapping gases in the atmosphere. Then they can release, or re-radiate, that heat. Some returns to Earth’s surface, keeping it warmer than it would be otherwise.

Earth receives solar energy from the sun (yellow), and returns energy back to space by reflecting some incoming light and radiating heat (red). Greenhouse gases trap some of that heat and return it to the planet’s surface. Image via NASA/Wikimedia.

Research on heat transmission

During the Cold War, the absorption of infrared radiation by many different gases was studied extensively. The work was led by the U.S. Air Force, which was developing heat-seeking missiles and needed to understand how to detect heat passing through air.

This research enabled scientists to understand the climate and atmospheric composition of all planets in the solar system by observing their infrared signatures. For example, Venus is about 870 F (470 C) because its thick atmosphere is 96.5% carbon dioxide.

It also informed weather forecast and climate models, allowing them to quantify how much infrared radiation is retained in the atmosphere and returned to Earth’s surface.

People sometimes ask me why carbon dioxide is important for climate, given that water vapor absorbs more infrared radiation and the two gases absorb at several of the same wavelengths. The reason is that Earth’s upper atmosphere controls the radiation that escapes to space. The upper atmosphere is much less dense and contains much less water vapor than near the ground, which means that adding more carbon dioxide significantly influences how much infrared radiation escapes to space.

Observing the greenhouse effect

Have you ever noticed that deserts are often colder at night than forests, even if their average temperatures are the same? Without much water vapor in the atmosphere over deserts, the radiation they give off escapes readily to space. In more humid regions radiation from the surface is trapped by water vapor in the air. Similarly, cloudy nights tend to be warmer than clear nights because more water vapor is present.

The influence of carbon dioxide can be seen in past changes in climate. Ice cores from over the past million years have shown that carbon dioxide concentrations were high during warm periods – about 0.028%. During ice ages, when the Earth was roughly 7 to 13 F (4-7 C) cooler than in the 20th century, carbon dioxide made up only about 0.018% of the atmosphere.

Even though water vapor is more important for the natural greenhouse effect, changes in carbon dioxide have driven past temperature changes. In contrast, water vapor levels in the atmosphere respond to temperature. As Earth becomes warmer, its atmosphere can hold more water vapor, which amplifies the initial warming in a process called the “water vapor feedback.” Variations in carbon dioxide have therefore been the controlling influence on past climate changes.

Small change, big effects

It shouldn’t be surprising that a small amount of carbon dioxide in the atmosphere can have a big effect. We take pills that are a tiny fraction of our body mass and expect them to affect us.

Today the level of carbon dioxide is higher than at any time in human history. Scientists widely agree that Earth’s average surface temperature has already increased by about 2 F (1 C) since the 1880s, and that human-caused increases in carbon dioxide and other heat-trapping gases are extremely likely to be responsible.

Without action to control emissions, carbon dioxide might reach 0.1% of the atmosphere by 2100, more than triple the level before the Industrial Revolution. This would be a faster change than transitions in Earth’s past that had huge consequences. Without action, this little sliver of the atmosphere will cause big problems.

See the full article here .

five-ways-keep-your-child-safe-school-shootings

Please help promote STEM in your local schools.

Stem Education Coalition

UNC-University of North Carolina
Carolina’s vibrant people and programs attest to the University’s long-standing place among leaders in higher education since it was chartered in 1789 and opened its doors for students in 1795 as the nation’s first public university. Situated in the beautiful college town of Chapel Hill, N.C., UNC has earned a reputation as one of the best universities in the world. Carolina prides itself on a strong, diverse student body, academic opportunities not found anywhere else, and a value unmatched by any public university in the nation.

From Michigan Technical University: “Necessary Negotiations of Bioenergy Development”

From Michigan Technical University

September 9, 2019
Kelley Christensen

MTU

When it comes to planting trees for bioenergy feedstocks, there are tradeoffs to be made.

As energy sources increasingly shift toward renewables, it’s important not to lose sight of the fact that energy production always comes with tradeoffs. Modeling the outcomes of those tradeoffs can help natural resource managers and policymakers create informed decisions in energy development.

Azad Heidari, a civil engineering doctoral candidate at Michigan Technological University, analyzed how biofuel poplar plantations in Wisconsin affect nearby water bodies. Heidari used a watershed model that combines hydrology and plant growth models calibrated to local conditions to investigate tradeoffs between biomass production and impacts on water flow and quality.

Heidari notes that using an interdisciplinary modeling approach allowed the researchers to come to much more holistic conclusions than they otherwise would have.

The work, coauthored by environmental engineers Alex Mayer and David Watkins, was published this summer in the Journal of Hydrology.

Decisions and Consequences

In any sort of energy development, priorities must be set. Growing corn for ethanol replaces a food crop in the same field. Tree plantations might displace pastures for livestock. It’s up to resource managers to determine which tradeoffs they can live with. Other Michigan Tech researchers also study energy production siting, such as replacing tobacco crop fields with solar farms and methods of harvesting renewable energy sources in a way that don’t significantly alter ecosystems.

In the case of planted poplar for biomass feedstocks, the main tradeoff is water usage.

“Poplar trees have a significantly higher water use during the growing season compared to the existing forest land,” Heidari said. “Planting poplar in over 70% of a typical watershed in northern Wisconsin would decrease the average streamflow up to 25%, and during the low flow months of July and August, up to 50%. These streamflow reductions could result in degradation of aquatic ecosystems and greater competition for water use.”

Heidari used the Soil and Water Assessment Tool (SWAT), frequently used by hydrologists, to test 70 different poplar cultivation scenarios to see how they played out at the watershed scale. He discovered that the impacts to streamflows could be partially mitigated by management techniques.

Planting density and harvest timing can reduce negative impacts. A properly managed poplar plantation using a high-density short rotation can produce greater biomass with smaller environmental impacts, including careful use of fertilizer to stimulate tree growth and minimize fertilizer loading that could lead to water quality degradation.

“The idea was if you plant at a higher density, there will be more water use. But what we found was the opposite,” Heidari said. “If you cut the trees down when they’re young, before they become too big and have high water use relative to annual growth, you can control the water use.”

Heidari said the model that produced the greatest biomass feedstock yield planted 1,100 trees in 100 square meters, but were harvested after five years. The 1,100 trees did not use more water in their growth than a simulation with 11 or 111 trees in the same size test plot because of how soon they were harvested, compared to later harvests in the lower density plantings.

Branching Out with Interdisciplinary Models

“There’s no obvious best solution because as you increase the yield and increase the bioenergy production from the feedstock, you have to use more water,” said Alex Mayer, professor in both the Department of Civil and Environmental Engineering and Department of Geological and Mining Engineering and Sciences.

Mayer said studies like this one are important because they provide a baseline of efficiencies to compare to fossil fuels, as well as provide a low-cost glimpse of future energy potential.

“That’s the power of using a model; you can explore how well you can manage a system,” he said. “We know there will be impacts, and the model shows us what’s the flexibility in managing those impacts.”

Watkins, a professor of civil and environmental engineering, noted, “In the popular literature, you see strong opinions about bioenergy — whether it’s absolutely a thing of the future for sustainability, or it’s not sustainable and we’re cutting down and burning all the trees. Bioenergy is really neither of those extremes. Modeling helps us understand and manage adverse impacts.

“A lot of watershed models we use in engineering do not include a detailed understanding of plant growth. SWAT was one of the few options for watershed scale hydrology that included plant growth,” Watkins said.

Next Steps

Heidari’s interdisciplinary approach to the SWAT model has produced benefits beyond the scope of his poplar and water study. He is working with the model developers to improve SWAT itself to better understand land management’s impacts on watersheds.

“This is a step toward improving our knowledge about biofuels and the related hydrology,” Heidari said. “Biofuels are important because energy has always been important; economies are dependent on energy.”

Heidari is extending his research on biofuel feedstocks by studying the growth of and water consumption by eucalyptus in Argentina and oil palm in Mexico. He will make similar recommendations on how best to manage these trees to maximize energy production and minimize water impacts.

See the full article here .

five-ways-keep-your-child-safe-school-shootings

Please help promote STEM in your local schools.

Stem Education Coalition

Michigan Technological University (http://www.mtu.edu) is a leading public research university developing new technologies and preparing students to create the future for a prosperous and sustainable world. Michigan Tech offers more than 130 undergraduate and graduate degree programs in engineering; forest resources; computing; technology; business; economics; natural, physical and environmental sciences; arts; humanities; and social sciences.
The College of Sciences and Arts (CSA) fills one of the most important roles on the Michigan Tech campus. We play a part in the education of every student who comes through our doors. We take pride in offering essential foundational courses in the natural sciences and mathematics, as well as the social sciences and humanities—courses that underpin every major on campus. With twelve departments, 28 majors, 30-or-so specializations, and more than 50 minors, CSA has carefully developed programs to suit many interests and skill sets. From sound design and audio technology to actuarial science, applied cognitive science and human factors to rhetoric and technical communication, the college offers many unique programs.

From McGill University: “Canadian astronomers determine Earth’s fingerprint in hopes of finding habitable planets beyond the Solar System”

From McGill University

28 Aug 2019

Media Contact
Nathalie Ouellette
Institute for Research on Exoplanets, Université de Montréal, Montréal, Canada
514-343-6111 x3195
nathalie@astro.umontreal.ca

Scientific Contact
Evelyn Macdonald
McGill Space Institute, McGill University, Montréal, Canada
evelyn.macdonald@mail.mcgill.ca

Nicolas Cowan
McGill Space Institute, McGill University, Montréal, Canada
514-398-1967
nicolas.cowan@mcgill.ca

Two McGill University astronomers have assembled a “fingerprint” for Earth, which could be used to identify a planet beyond our Solar System capable of supporting life.

McGill Physics student Evelyn Macdonald and her supervisor Prof. Nicolas Cowan used over a decade of observations of Earth’s atmosphere taken by the SCISAT satellite to construct a transit spectrum of Earth, a sort of fingerprint for Earth’s atmosphere in infrared light, which shows the presence of key molecules in the search for habitable worlds.

SCISAT-1 is a Canadian satellite designed to make observations of the Earth’s atmosphere. Image from NASA

This includes the simultaneous presence of ozone and methane, which scientists expect to see only when there is an organic source of these compounds on the planet. Such a detection is called a “biosignature”.

“A handful of researchers have tried to simulate Earth’s transit spectrum, but this is the first empirical infrared transit spectrum of Earth,” says Prof. Cowan. “This is what alien astronomers would see if they observed a transit of Earth.”

The findings, published Aug. 28 in the journal Monthly Notices of the Royal Astronomical Society, could help scientists determine what kind of signal to look for in their quest to find Earth-like exoplanets (planets orbiting a star other than our Sun). Developed by the Canadian Space Agency, SCISAT was created to help scientists understand the depletion of Earth’s ozone layer by studying particles in the atmosphere as sunlight passes through it. In general, astronomers can tell what molecules are found in a planet’s atmosphere by looking at how starlight changes as it shines through the atmosphere. Instruments must wait for a planet to pass – or transit – over the star to make this observation. With sensitive enough telescopes, astronomers could potentially identify molecules such as carbon dioxide, oxygen or water vapour that might indicate if a planet is habitable or even inhabited.

Cowan was explaining transit spectroscopy of exoplanets at a group lunch meeting at the McGill Space Institute (MSI) when Prof. Yi Huang, an atmospheric scientist and fellow member of the MSI, noted that the technique was similar to solar occultation studies of Earth’s atmosphere, as done by SCISAT.

Since the first discovery of an exoplanet in the 1990s, astronomers have confirmed the existence of 4,000 exoplanets. The holy grail in this relatively new field of astronomy is to find planets that could potentially host life – an Earth 2.0.

A very promising system that might hold such planets, called TRAPPIST-1, will be a target for the upcoming James Webb Space Telescope, set to launch in 2021.

A size comparison of the planets of the TRAPPIST-1 system, lined up in order of increasing distance from their host star. The planetary surfaces are portrayed with an artist’s impression of their potential surface features, including water, ice, and atmospheres. NASA

ESO Belgian robotic Trappist National Telescope at Cerro La Silla, Chile

ESO Belgian robotic Trappist-South National Telescope at Cerro La Silla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

NASA/ESA/CSA Webb Telescope annotated

Macdonald and Cowan built a simulated signal of what an Earth-like planet’s atmosphere would look like through the eyes of this future telescope which is a collaboration between NASA, the Canadian Space Agency and the European Space Agency.

The TRAPPIST-1 system located 40 light years away contains seven planets, three or four of which are in the so-called “habitable zone” where liquid water could exist. The McGill astronomers say this system might be a promising place to search for a signal similar to their Earth fingerprint since the planets are orbiting an M-dwarf star, a type of star which is smaller and colder than our Sun.

“TRAPPIST-1 is a nearby red dwarf star, which makes its planets excellent targets for transit spectroscopy. This is because the star is much smaller than the Sun, so its planets are relatively easy to observe,” explains Macdonald. “Also, these planets orbit close to the star, so they transit every few days. Of course, even if one of the planets harbours life, we don’t expect its atmosphere to be identical to Earth’s since the star is so different from the Sun.”

According to their analysis, Macdonald and Cowan affirm that the Webb Telescope will be sensitive enough to detect carbon dioxide and water vapour using its instruments. It may even be able to detect the biosignature of methane and ozone if enough time is spent observing the target planet.

Prof. Cowan and his colleagues at the Montreal-based Institute for Research on Exoplanets are hoping to be some of the first to detect signs of life beyond our home planet. The fingerprint of Earth assembled by Macdonald for her senior undergraduate thesis could tell other astronomers what to look for in this search. She will be starting her Ph.D. in the field of exoplanets at the University of Toronto in the Fall.

Funding for the research was provided by the Natural Sciences and Engineering Research Council of Canada, the Fonds de recherche du Québec – Nature et technologies, and a McGill Science Undergraduate Research Award.

See the full article here .

five-ways-keep-your-child-safe-school-shootings

Please help promote STEM in your local schools.

Stem Education Coalition

All about
McGill

With some 300 buildings, more than 38,500 students and 250,000 living alumni, and a reputation for excellence that reaches around the globe, McGill has carved out a spot among the world’s greatest universities.
Founded in Montreal, Quebec, in 1821, McGill is a leading Canadian post-secondary institution. It has two campuses, 11 faculties, 11 professional schools, 300 programs of study and some 39,000 students, including more than 9,300 graduate students. McGill attracts students from over 150 countries around the world, its 8,200 international students making up 21 per cent of the student body.

From Michigan Technical University: “Geohazards on the Horizon”

From Michigan Technical University

August 23, 2019
Jen A. Miller

There’s a method to my disaster management.

India is in a unique position with climate change. It’s a densely populated country that is prone to geohazards like earthquakes, tsunamis, landslides and floods. Because of that density, one disaster can hurt a lot of people, as happened in August of this year when a mudslide in southern India killed 66 people and displaced at least 360,000.

A view of the landslide that destroyed the Munnar College building. Image Credit: I&PRD August 20th

Mumbai alone has a population of 19 million people, but only one university there, the Tata Institute of Social Sciences (TISS), offers a degree in disaster management and mitigation.

“This is a pressing need,” said Thomas Oommen, associate professor of geological and mining engineering sciences and affiliated associate professor of civil and environmental engineering at Michigan Tech. “Technologies used today in disaster management need to be taught to students so they can be ready for when a disaster hits a community this large.”

Oommen was given a grant from the U.S. Consulate General in Mumbai to travel there, along with Tim Frazier from Georgetown University and Himanshu Grover from the University of Washington, to meet with faculty and administration from TISS as well as Indian officials. For two weeks in August, they worked to identify gaps in the TISS program and develop a state-of-the-art disaster management curriculum to be implemented at TISS. They will continue to meet via an online portal every month to continue work on the curriculum, which they hope can then be replicated at universities across India to train more people to handle the disasters to come.

Oommen sees this becoming a way to train professionals already working in the field.

“We want to see if there are shorter programs that can be delivered to people who are already working in this field, like an adult education program or continuing education program, so more people can be trained in this area,” he said.

Bridging new remote sensing research and effective education — built on good communication and getting timely, accurate info to the right people — is a key part of the methodology behind Oommen’s global geohazards work.

Flooding in India’s Idukki district. Image Credit: I&PRD August 20th

See the full article here .

five-ways-keep-your-child-safe-school-shootings

Please help promote STEM in your local schools.

Stem Education Coalition

Michigan Technological University (http://www.mtu.edu) is a leading public research university developing new technologies and preparing students to create the future for a prosperous and sustainable world. Michigan Tech offers more than 130 undergraduate and graduate degree programs in engineering; forest resources; computing; technology; business; economics; natural, physical and environmental sciences; arts; humanities; and social sciences.
The College of Sciences and Arts (CSA) fills one of the most important roles on the Michigan Tech campus. We play a part in the education of every student who comes through our doors. We take pride in offering essential foundational courses in the natural sciences and mathematics, as well as the social sciences and humanities—courses that underpin every major on campus. With twelve departments, 28 majors, 30-or-so specializations, and more than 50 minors, CSA has carefully developed programs to suit many interests and skill sets. From sound design and audio technology to actuarial science, applied cognitive science and human factors to rhetoric and technical communication, the college offers many unique programs.

From CSIROscope: “Every week is science week on RV Investigator!”

From CSIROscope

CSIRO RV Investigator. CSIRO Australia

The secrets of the Coral Sea are not given up easily. But the scientists, research assistants and crew on RV Investigator are more than equipped to delve deep for answers.

Those onboard are an industrious and intrepid bunch, finding ways to overcome the challenges of remote work at sea. But what have they been up to in the last few weeks since the voyage began?

Our 94-metre floating laboratory is now drawing a picture of a chain of ancient seafloor volcanoes. The researchers will then describe the interplay of the sea plates, which are the focus of this voyage.

Analyse this!

A typical geoscience voyage on Investigator comes with all the trappings of using dredges to sample the seafloor. This includes snagged dredging equipment 2500 m below the surface, broken shear pins which upend the basket carrying rock samples (sending them back to the seafloor), a two-to-three metre sea swell and 25 knot (46 km/hr) winds blowing for three straight days.

So far on this voyage, there have been 22 dredges of the seafloor from sites starting about 1000 km south-east of Cairns. By the end of this voyage, it is hoped more than 36 sites will have been surveyed and sampled in the waters of Australia, Papua New Guinea, Solomon Islands and New Caledonia.

This work has been released into the public domain by its author, Kahuroa. Wikipedia.

Voyage Chief Scientist, Associate Professor Jo Whittaker from the University of Tasmania, said while most of the rocks being hauled to the surface were what was expected, the real value came when the ship arrives back at port.

“There is a lot of geochemistry to be done and age dating,” Jo said.

“We have basalt, lavas and carbonates. What we don’t have so far is continental rocks – rocks which could show that a large area of the seafloor out here was rifted from continental Australia millions of years ago.

“Early in the voyage, we did get some cool carbonate rocks which had alternate layers of algal and coral fossils. Algae needs sunlight to grow, so while the rocks were from about 1000 m down today, in the past they were at sea level. This highlights how sea levels have changed over time.”

A bathymetry image (seafloor image) of Frederick Reef. The scientists use this to pick rock dredge sites and better understand the seamounts deep below.

The early bird catches the flying fish

The science on Investigator is all around you, and around the clock. The science team, as they are known, work alternating 12-hour shifts. Everywhere you look, there are scientists, researchers and students busy with their work 24 hours a day.

Sitting in a small enclosed deck 25 m above the waterline is a dedicated trio of bird and mammal observers from Birdlife Australia. Led by Principal Investigator and BirdLife Tasmania Convenor, Dr Eric Woehler, the team (which includes volunteer observers Jessica Bolin and Josie Lumley) scan the horizon from dawn to dusk. They’re spotting, identifying and logging marine birds and mammals. And any plastic or other jetsam (rubbish from ships) that passes within range.

Since the start of the voyage, more than 6000 individuals from 23 species of bird have been logged. Red-footed, brown and masked boobies have been the main species. But winging their way around the ship have also been storm petrels, wedge-tailed shearwaters, and frigatebirds. With the ship heading further north toward Papua New Guinea, the eagle-eyed observers are now seeing white-tailed tropicbirds.

Eric has more than earned his sea legs and bird skills. He has clocked up more than 400 days at sea on the Australian Antarctic Division’s research and supply vessel (RSV) Aurora Australis. He’s been spotting, identifying and logging birds across the Southern Ocean from Australia to Antarctica. Now on his tenth voyage on Investigator, when Eric steps ashore from a voyage in January next year, he would have logged more than 140 days onboard and circumnavigated Australia in the process.

Look up! The scientists aren’t just looking deep below for the answers. Image: Huw Morgan

Extreme birdwatching

Eric’s enthusiasm for birds is matched by his passion for inspiring and educating anyone who comes within range on the life and times of seabirds.

“Australia has about 130 to 140 seabird species and I would expect we will see about 40 of those on this voyage,” Eric says from behind binoculars which seem glued to his face.

As he speaks, what seems like a black blur passes overhead.

“The lesser frigatebird – an amazing bird,” Eric reveals.

“They have the lowest body mass to wing-loading ratio of any bird. They hardly have to flap their wings at all.”

“It’s a kleptoparasite – it steals food from other birds.”

Pilot whales, dolphins, a 2.5 m hammerhead shark, and a lone whale shark have also made appearances.

Lying about 1000 km east of Cairns, the ship is currently drawing near the very remote Mellish Reef. About 10 km long and 3 km wide, the reef has only a small area of land permanently above the highwater mark. This speck of land is the nesting ground for thousands of birds.

Before we reach the reef, Eric hurries outside to the open deck with his camera and captures a truly remarkable image of a pair of red-footed boobies right on the tail of a flying fish spooked out of the sea by the ship.

The booby wins.

Red-footed Booby vs flying fish – some of the sights on RV Investigator. Image: Eric Woehler, BirdLife Tasmania

See the full article here .

five-ways-keep-your-child-safe-school-shootings

Please help promote STEM in your local schools.

Stem Education Coalition

SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia

So what can we expect these new radio projects to discover? We have no idea, but history tells us that they are almost certain to deliver some major surprises.

Making these new discoveries may not be so simple. Gone are the days when astronomers could just notice something odd as they browse their tables and graphs.

Nowadays, astronomers are more likely to be distilling their answers from carefully-posed queries to databases containing petabytes of data. Human brains are just not up to the job of making unexpected discoveries in these circumstances, and instead we will need to develop “learning machines” to help us discover the unexpected.

With the right tools and careful insight, who knows what we might find.

CSIRO, the Commonwealth Scientific and Industrial Research Organisation, is Australia’s national science agency and one of the largest and most diverse research agencies in the world.

From Woods Hole Oceanographic Institute: “Underwater robots swarm the ocean”

From Woods Hole Oceanographic Institute

August 21, 2019
Evan Lubofsky

(Illustration by Tim Silva, Woods Hole Oceanographic Institution)

Underwater robots do a lot these days. They can be programmed to go to remote, dangerous, and often previously unexplored parts of the ocean to measure its key characteristics—from salinity and temperature to the speed and direction of currents. They map the seafloor and benthic environments in outstanding detail. And, they find things—from shipwrecks and downed war planes to the billowing plumes of hydrothermal vents in the deep sea.

These smart workhorses of the ocean have become so useful, in fact, that some ocean scientists like Erin Fischell can’t get enough of them.

“Instead of using just a single, larger and more expensive underwater robot to cover an area of the ocean, we want to have hundreds or even thousands of smaller, lower-cost robots that can all work in sync to give us a more complete picture of what’s happening,” said Fischell, who develops autonomous underwater vehicle (AUV) technology at Woods Hole Oceanographic Institution (WHOI). “This will give us better spatial and temporal coverage in the areas we’re trying to study, and provide us with much richer and robust data sets in far less time.”

Getting in sync

For underwater robots to become the vast and coordinated ocean monitoring network that Fischell envisions, they need to form underwater ‘swarms’ that move en masse through the ocean—not unlike schools of fish. Swarming has already shown promise in disaster rescue missions and other applications on land, but we haven’t yet been able to extend the capability to the ocean due to basic physics. Radio signals, such as those generated by GPS navigation systems, travel at the speed of light. But the absorption of light in water is 10 trillion times greater than that in air, so radio signals can’t go very far underwater and thus aren’t viable for underwater communications.

To overcome these limitations, underwater robot navigation has traditionally relied upon different kinds of technologies such as high-power inertial navigation sensors (INS) that cost hundreds of thousands of dollars. Fischell says that while these pricey peripherals would be impractical for low-cost underwater vehicles, a robot attempting to navigate without INS technology can quickly run into severe issues.

“These low-cost ocean robots can drift hundreds of meters every 10 minutes, so if you leave one down there for an hour, it can end up being a kilometer off from where you think it is,” she said. “It doesn’t take long for them to lose their way.”

And that’s just a single unit. If you want a fleet of robots moving collectively in the same direction, the lack of accurate, controllable navigation becomes a show stopper.

Do you hear what I hear?

Fischell has been working with MIT professor Henrik Schmidt and Nicholas Rypkema, a researcher at MIT and former MIT/WHOI Joint Program graduate student, to bridge this capability gap with the development of a new acoustic-based navigation system. It includes a series of small, economical underwater robots known as SandSharks that eavesdrop on a pulsing underwater speaker—or acoustic beacon—that transmits sound into the ocean every second. The robots listen in with help of underwater microphones that pick up the acoustic signals, enabling the system’s control software to determine the distance and angle of each robot relative to the beacon. In this sense, the beacon acts as a common reference point for each robot, allowing them to navigate collectively in a swarm.

“Once we know range and angle, we can figure out where a robot is relative to the sound source,” Fischell said.

Three ready-to-deploy SandShark robots on a dock before engineers launch them into Boston’s Charles River. (Photo by Nick Rypkema, Massachusetts Institute of Technology)

Field proven

The system was recently field tested in Boston’s Charles River. A kayak acted as command central, with an acoustic beacon mounted off its side and a shoe-box sized control box placed inside the cockpit.

“The controls are very easy for the user—there’s a simple four-way switch for Follow, Sample, Return, and Abort,” Fischell said.

Three low-cost robots were launched from shore and cruised at roughly 2 meters below the surface. Once “Follow” mode was selected during the field tests, the robots began receiving the acoustic bleeps and moments later, all three were moving in the same pattern relative to the beacon attached to the kayak as it glided around the river.

“As the beacon moved though the water, all of the robots followed along, which made it easy for the user to understand what was going on,” Fishchell said. “We put strobe lights on the robots so we could see them moving in sync through the water.”

The system also offers a great deal of flexibility with respect to controlling the swarm. Depending on the mission, the robots can cruise in various lines, angles, and circles relative to the beacon, and line up together in virtual arrays.

“The robots’ course can easily be changed if the ocean features that are being monitoried—like fronts or plumes, for example—shift in space,” Fischell said.

Scaling up

The team appears to have solved a big problem for tiny robots—and one that oceanographers have grappled with for quite some time, according to Rypkema.

“Swarms of underwater vehicles have been a dream for researchers for decades, and the nature of the ocean means that these swarms can have an enormous impact on understanding its properties and dynamics,” he said.

Getting a fleet of three robots to work cooperatively is a huge win, but Fischell and her colleagues are thinking much bigger. They ultimately want a scalable network of hundreds of robots roaming the ocean.

“There are a lot of underwater robots out there in the sub-$10,000 price range,” Fischell said. “So as we optimize our technology and methods, we can hopefully get a lot of these vehicles working together for less cost than some of the larger and more complex robots we’ve had to rely on.”

This work is supported by the Office of Naval Research (ONR), Battelle, the Defense Advanced Research Projects Agency (DARPA) and the Reuben F. and Elizabeth B. Richards Endowed Fund at WHOI.

See the full article here .

five-ways-keep-your-child-safe-school-shootings

Please help promote STEM in your local schools.

Stem Education Coalition

Woods Hole Oceanographic Institute

Vision & Mission

The ocean is a defining feature of our planet and crucial to life on Earth, yet it remains one of the planet’s last unexplored frontiers. For this reason, WHOI scientists and engineers are committed to understanding all facets of the ocean as well as its complex connections with Earth’s atmosphere, land, ice, seafloor, and life—including humanity. This is essential not only to advance knowledge about our planet, but also to ensure society’s long-term welfare and to help guide human stewardship of the environment. WHOI researchers are also dedicated to training future generations of ocean science leaders, to providing unbiased information that informs public policy and decision-making, and to expanding public awareness about the importance of the global ocean and its resources.
Mission Statement

The Woods Hole Oceanographic Institution is dedicated to advancing knowledge of the ocean and its connection with the Earth system through a sustained commitment to excellence in science, engineering, and education, and to the application of this knowledge to problems facing society.