Solar project uses 120,000 metric tons of molten salt
We were surprised at first to read that the giant Abengoa Solana solar energy project had to import 120,000 metric tons of molten salt from Chile. After all, Arizona has numerous massive salt deposits some of which are being actively mined. But then we learned that the molten salt mixes for thermal storage are typically 60% sodium nitrate and 40% potassium nitrate. The mixtures vary and and also include calcium nitrates.
The 280-megawatt, 3 square mile, $2 billion project will use the molten salt as a heat storage sink that will allow electricity to be generated for as long as 6 hours after the sun sets, according to a report in the Arizona [Phoenix] Republic. [Right, diagram of plant design. Credit, US Dept. Energy]
Second of a three-part series. To read the first part, click here.
Snaking beneath the surface of many Eastern cities is a network of aging, cast-iron pipes carrying natural gas. The pipes, buried underground, have been shifted for decades by winter freeze-thaw cycles, and some are simply cracked from age. Because of this, some pipes leak.
Just how much gas from those older pipes and their newer replacements in the pipeline distribution system leaks out and rises into the atmosphere, though, is up for debate. Because methane, which makes up about 95 percent of the natural gas in pipelines, is about 25 times more potent as a greenhouse gas than carbon dioxide, the leakage raises a troubling climate question: How clean is natural gas?
The growing role of natural gas in the United States’ energy mix makes it more important to quantify the leakage. If that number is significant, it could negate the climate benefit of natural gas — measured against coal — unless the leaks are plugged.
“It’s outrageous and it’s astounding, how little we know [about leaks],” said Nathan Phillips, a Boston University researcher who is working to figure out how much methane is leaking from cities.
Getting accurate measurements of the exact amount of gas leaking from any given city system is difficult. Phillips should know: Last year, his research team found the city of Boston’s pipeline distribution system had more than 3,000 leaks.
But though they know there are a lot of leaks, they have yet to determine how much gas is coming out of them. That’s what Phillips is working on now. Scientists have proposed other ways of estimating methane emissions from distribution systems, but they all suffer from significant limitations.
Cornell University researcher Robert Howarth and others have suggested using a number the government collects from every gas distribution company in the country. This metric is called “lost and unaccounted for” gas. The federal Pipeline and Hazardous Materials Safety Administration defines it as the difference between what the gas company sends out through its pipeline system and what gets metered at the receiving end.
Missing in action in the gas business
Say the gas company sends out 100 cubic feet of gas. Some of it might leak out of a pipe and into the soil. Cooling temperatures might make the gas contract, so the meter on the other end reads it as less gas. Some might waft through another leaky pipe out of a manhole or a crack in the asphalt, and into the atmosphere.
At the end, only 97 cubic feet get to customers. The missing 3 cubic feet? That’s what industry calls “lost and unaccounted for.”
According to PHMSA, there are two main reasons for this “lost” gas. The first is leaks. The second is measurement issues caused by inconsistent meters or those temperature and pressure variations that cause meters to measure more or less gas, depending on environmental conditions.
Logically, say Howarth and other researchers interested in how much methane leaks to the atmosphere, a higher lost and unaccounted for percentage would mean more gas is escaping the system and warming the planet.
“If one company reports 4 percent lost gas consistently across years and another reports 1 percent, wouldn’t you expect the first company’s pipelines to be responsible for more methane leakage to the atmosphere?” asked Robert Jackson, a Duke University scientist who is conducting research into methane losses from cities.
The numbers do vary, and some utilities are consistently higher than others in their percentages of lost and unaccounted for gas.
Southern California Gas Co., the largest gas distribution company in the nation, reported a 0.87 percent loss rate in 2012; in 2011, that rate was 0.84 percent. In comparison, Washington Gas Light Co., which serves the greater District of Columbia, had a 3.65 percent loss rate in 2012; in 2011 it was 4.04 percent.
Yet while there is probably some correlation between this percentage and losses to the atmosphere, it is difficult to tease out which part of that is the part that escapes, said Boston University’s Phillips.
Some losses are impossible
“Right now we can’t say that ‘unaccounted for’ means leaks,” Phillips said. “It’s some black box that includes leaks, accounting errors and meter errors.”
Additionally, the reported numbers on lost and unaccounted for gas often seem unreliable. In 2012, PHMSA data on lost and unaccounted for rates from gas companies included a range of numbers that defied the possible.
One company, Indiana Utilities Corp., responsible for 139 miles of total pipeline, was listed as having a 563 percent lost and unaccounted for rate. Many others, mostly small systems of less than 200 pipeline miles, were listed at improbably high percentages of lost and unaccounted for gas.
In an emailed statement responding to a query on why the lost and unaccounted for numbers appeared to have so many errors, PHMSA said the responsibility for the data’s accuracy lay with the reporting company.
“The accuracy of the data provided for unaccounted for gas is dependent on the operator’s ability to understand how to calculate the formula. PHMSA data staff will be following-up with operators to verify data accuracy,” the statement read.
In a telephone interview, Frank Czeschin, the president of Indiana Utilities Corp., opened up the electronic file of his 2012 report to PHMSA in order to look over his numbers.
“I just pulled my actual report, and it indicated 0.563 percent. I do not know how the report you pulled was missing the decimal,” said Czeschin, who added that PHMSA had not contacted him about the supposed 563 percent loss.
Industry experts say the lost and unaccounted for rate should be no higher than 3 percent. PHMSA recommends contacting the company if the rate is more than 10 percent.
In the PHMSA database, which lists more than 1,400 gas companies, 72 companies reported lost and unaccounted for rates of 10 percent or higher. Two-hundred-and-seventy-five companies had a rate between 3 and 9.9 percent.
How much goes up? The jury remains out
The natural gas industry, represented by the American Gas Association, says the reported lost and unaccounted for percentages should not be used as a proxy for emissions. “It doesn’t have anything to do with emissions or with what actually is emitted into the atmosphere,” said Pamela Lacey, AGA’s senior managing counsel for environment.
For its part, AGA is quick to highlight U.S. EPA’s estimates of methane emissions from natural gas. EPA has said that, from the gas well to your stovetop, the industry leaks 1.4 percent of the gas it produces.
For the pipeline distribution system, the agency calculates this loss based on leak rates calculated from a 1996 study, conducted in collaboration with the Gas Research Institute (now the Gas Technology Institute). That study took leak measurements from participating gas companies for different kinds of pipes: cast iron, unprotected and protected steel, and plastic.
To determine total leaks, the agency multiplies the leak rate by the miles of pipe, subtracts any emissions reductions techniques reported by gas companies and comes up with a final emissions number. Cornell’s Howarth has argued that this study underestimates emissions from natural gas.
New research to re-examine distribution system leak rates has been funded by the Environmental Defense Fund as part of a larger project to quantify lost methane from the natural gas system. Much of the field work on that is being done this year, headed up by Brian Lamb, a researcher at Washington State University.
“The whole objective of our work is to develop this database of direct emission and leak rates,” said Lamb.
Another EDF-funded study is also underway in Boston, where Harvard University professor Steven Wofsy and others are working to use measurements of methane in the atmosphere above the city to determine how much of the gas is being released. They expect to publish those results in the fall.
Among these unknowns, there is one data point that is widely accepted: The pipelines will continue leaking.
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Because of their location’s geology, Icelandic volcanoes are known to be directly connected to the Earth’s mantle. New research shows that a volcano in Costa Rica may have a direct connection to the mantle too, despite lying on a much thicker part of Earth’s crust. This discovery suggests that eruptions in a wider range of volcanoes might be predicted by techniques such as earthquake monitoring, something proposed for Icelandic volcanoes. But it also suggests that volcanoes can recharge with magma very quickly, raising the risk of a sudden eruption.
Tectonic plates cover the Earth’s surface. The boundaries between these plates can be dangerous places, with earthquakes, volcanoes, and tsunamis all originating along the places where plates meet. The plates create two types of volcanoes. Those that sit on oceanic crust are directly connected to the mantle (the thick layer between the Earth’s crust and molten outer core); they spew magma directly from it. Others erupt magma that has been heated, mixed, and stored in magma chambers over an extended period. These are assumed to lack a direct connection to the mantle.
Icelandic volcanoes are an example of the former, occurring on the mid-ocean ridge of the North Atlantic where crust is constantly being created. In contrast, most volcanoes around the Pacific rim, including the Costa Rican volcano, have been assumed to be examples of the latter.
That, however, turns out not to be the case, as shown by the work of Philipp Ruprecht and Terry Plank of Columbia University, who published their results in Nature. They studied ash ejected during an eruption of the Irazu volcano in Costa Rica, which occurred between 1963 and 1965, to draw this conclusion.
They measured the amount of the metal nickel in olivine crystals found in the ash. These crystals preserve variations in nickel content depending on how they are formed within the magma. Thus, studying this variation can reveal where the magma actually came from and how long its journey from the depths took. From their data, Ruprecht and Plank could detect that there was a shallow chamber underneath the volcano that refills with melt from the mantle.
While such chambers are common, what was surprising was the timescale at which the chamber refilled. It took as little as a matter of months, which is rapid for geology. The Irazu volcano is an arc-type volcano, which is formed when oceanic crust dives into the mantle beneath a continental plate, causing melting. In an arc volcano, a quick refill could happen only if the magma chamber is directly connected to the mantle. (These arc-type volcanoes are a subset of “stratovolcanoes” that are capable of huge explosions and devastating eruptions that throw ash high into the stratosphere, more than 10 km above the ground.)
According to Sally Gibson of the University of Cambridge, who was not involved in the study, “It has widely been assumed that the so-called ‘arc’ volcanoes’ magma is the result of stalling and crystallization of primitive mantle melts in long-lived chambers that exist over a range of depths in the continental crust. Ruprecht and Plank’s findings show that the melts beneath the Irazu volcano must have ascended through the crust very rapidly.”
Gibson suggests that this sort of migration of the magma is similar to that found in Icelandic volcano systems. The Icelandic magmatic movement can be detected by seismic activity in the area, so Ruprecht and Plank’s results suggest that geophysical seismic monitoring of small earthquakes in the deep crust may provide advance warning of eruption risks. Of course, given the speed of refilling seen here, we may have to extend monitoring to volcanoes that were generally thought to be at a relatively low risk of eruption.
Cheaper than most, better than all: the 2013 Nexus 7 reviewed
Great screen, fast internals make this refreshed tablet a great deal at any price.
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The loss of sea ice is expected to lead to isolation and increased inbreeding among Arctic foxes, which currently use ice to travel between populations. (Jeff Kerby/Science)
The melting of Arctic sea ice as the climate warms is such a dramatic change to northern ecosystems that it will have a serious impact not just on ocean dwellers such as whales and seals, but land animals such as caribou and foxes, scientists say.
Caribou may be affected by changes in their food sources, as a result of the warming climate, and increased human activity along shipping routes may affect their migration. (Mark Post/Penn State University)The proportion of the Arctic covered by sea ice during the summer hit a record low in 2012. Since 1979, the summer sea ice coverage has declined by about three-million kilometres squared, losing an area larger than the province of New Brunswick each year, scientific records show. Because dark open water reflects far less sunlight than ice, warming accelerates with sea ice loss, which in turn causes the ice to melt more quickly.
While most people see the loss of sea ice as a sign or indicator of climate change, it’s far more than that, say U.S. and Canadian scientists in a paper published Thursday online in the journal Science.
Sea ice in the Arctic is analogous to trees in a forest, said Jedediah Brodie, a conservation ecologist at the University of British Columbia who co-authored the paper.
“When you cut the trees, you alter the entire ecosystem — every other species that lives in a forest in some way depends on those trees,” he said in a phone interview.
‘Loss of a globally important ecosystem’
The loss of sea ice is “actually the loss of a habitat,” he added, “and that’s the loss of a globally important ecosystem.”
Sea ice plays a huge role in the Arctic because 80 per cent of the low-lying tundra is within 100 kiometres of the ocean that is covered by ice for at least part of the year.
Penn State University biologist Eric Post, lead author of the paper, wanted to examine the relationships among Arctic organisms from algae to whales to bears, and compile the ways in which they might be affected by the loss of sea ice. He sought help from experts in the U.S. and Canada, including Brodie, who researches how environmental change affects ecosystems; University of Calgary veterinary medicine researcher Susan Kutz; and University of Alberta polar bear specialist Ian Stirling.
It’s most obvious that sea ice loss will affect marine organisms, but some of the specific effects are not intuitive.
Polar bears are spending more time on land as the sea ice melts, leading to increased contact with grizzly bears. Interbreeding has created hybrids, such as this one shot on Banks Island, N.W.T., in 2006. (Canadian Press)For example, the loss of ice reduces the fat content of algae that live between layers of ice, making them less nourishing to marine animals, the researchers noted.
The melting ice is also changing the timing each summer of huge blooms of phytoplankton that form the base of the Arctic food chain, which may shorten the season for the blooms, causing ripples all the way up the food chain to fish, seabirds and marine mammals such as seals and whales.
Many marine mammals such as seals also rely on sea ice as a place to raise their young or even just to rest after long dives in search of fish. As the sea ice disappears, animals such as walruses have been crowding onto shorelines, which can lead to their young being trampled or the spread of disease through the population.
The loss of sea ice also has many indirect, inintuitive effects on both marine and land animals.
“It can have pretty dramatic effects on climate even far inland,” Brodie said.
That in turn can affect the growth of vegetation on land, disrupting food sources for animals such as caribou.
Indirect effects on migration, breeding
The article notes a number of other potential indirect effects of sea ice loss on land animals:
Isolation and increased inbreeding among populations of wolves and arctic foxes, which currently use ice to travel between populations during most of the year.
Increased interbreeding and hybridization between grizzly bears and polar bears because polar bears are spending more time on land, where they come into contact with grizzlies.
The spread of diseases that were once restricted by sea ice barriers to a certain part of the Arctic, such as phocine distemper virus, which currently affects only eastern Arctic seals.
Increased shipping in the Canadian Arctic and the later freeze up of the ice could affect the annual migration of the Dolphin and Union caribou herd.
The paper noted that it is a challenge to forsee how sea ice decline will increase human activities such as shipping and industrial development in the Arctic, which could also have negative consequences for many species.
Claim: Climate change is 10x faster than ever before
Posted on August 1, 2013 by Anthony Watts
From Stanford University comes this breathless missive that sounds just like every one we’ve heard before. No mention of “the pause”, but we do have a “baked into the system” goodness apparently.
climate_speed
Climate change occurring 10 times faster than at any time in past 65 million years
The planet is undergoing one of the largest changes in climate since the dinosaurs went extinct. But what might be even more troubling for humans, plants and animals is the speed of the change. Stanford climate scientists warn that the likely rate of change over the next century will be at least 10 times quicker than any climate shift in the past 65 million years.
If the trend continues at its current rapid pace, it will place significant stress on terrestrial ecosystems around the world, and many species will need to make behavioral, evolutionary or geographic adaptations to survive.
Although some of the changes the planet will experience in the next few decades are already “baked into the system,” how different the climate looks at the end of the 21st century will depend largely on how humans respond.
The findings come from a review of climate research by Noah Diffenbaugh, an associate professor of environmental Earth system science, and Chris Field, a professor of biology and of environmental Earth system science and the director of the Department of Global Ecology at the Carnegie Institution. The work is part of a special report on climate change in the current issue of Science.
Diffenbaugh and Field, both senior fellows at the Stanford Woods Institute for the Environment, conducted the targeted but broad review of scientific literature on aspects of climate change that can affect ecosystems, and investigated how recent observations and projections for the next century compare to past events in Earth’s history.
For instance, the planet experienced a 5 degree Celsius hike in temperature 20,000 years ago, as Earth emerged from the last ice age. This is a change comparable to the high-end of the projections for warming over the 20th and 21st centuries.
The geologic record shows that, 20,000 years ago, as the ice sheet that covered much of North America receded northward, plants and animals recolonized areas that had been under ice. As the climate continued to warm, those plants and animals moved northward, to cooler climes.
“We know from past changes that ecosystems have responded to a few degrees of global temperature change over thousands of years,” said Diffenbaugh. “But the unprecedented trajectory that we’re on now is forcing that change to occur over decades. That’s orders of magnitude faster, and we’re already seeing that some species are challenged by that rate of change.”
Some of the strongest evidence for how the global climate system responds to high levels of carbon dioxide comes from paleoclimate studies. Fifty-five million years ago, carbon dioxide in the atmosphere was elevated to a level comparable to today. The Arctic Ocean did not have ice in the summer, and nearby land was warm enough to support alligators and palm trees.
“There are two key differences for ecosystems in the coming decades compared with the geologic past,” Diffenbaugh said. “One is the rapid pace of modern climate change. The other is that today there are multiple human stressors that were not present 55 million years ago, such as urbanization and air and water pollution.”
Record-setting heat
Diffenbaugh and Field also reviewed results from two-dozen climate models to describe possible climate outcomes from present day to the end of the century. In general, extreme weather events, such as heat waves and heavy rainfall, are expected to become more severe and more frequent.
For example, the researchers note that, with continued emissions of greenhouse gases at the high end of the scenarios, annual temperatures over North America, Europe and East Asia will increase 2-4 degrees C by 2046-2065. With that amount of warming, the hottest summer of the last 20 years is expected to occur every other year, or even more frequently.
By the end of the century, should the current emissions of greenhouse gases remain unchecked, temperatures over the northern hemisphere will tip 5-6 degrees C warmer than today’s averages. In this case, the hottest summer of the last 20 years becomes the new annual norm.
“It’s not easy to intuit the exact impact from annual temperatures warming by 6 C,” Diffenbaugh said. “But this would present a novel climate for most land areas. Given the impacts those kinds of seasons currently have on terrestrial forests, agriculture and human health, we’ll likely see substantial stress from severely hot conditions.”
The scientists also projected the velocity of climate change, defined as the distance per year that species of plants and animals would need to migrate to live in annual temperatures similar to current conditions. Around the world, including much of the United States, species face needing to move toward the poles or higher in the mountains by at least one kilometer per year. Many parts of the world face much larger changes.
The human element
Some climate changes will be unavoidable, because humans have already emitted greenhouse gases into the atmosphere, and the atmosphere and oceans have already been heated.
“There is already some inertia in place,” Diffenbaugh said. “If every new power plant or factory in the world produced zero emissions, we’d still see impact from the existing infrastructure, and from gases already released.”
The more dramatic changes that could occur by the end of the century, however, are not written in stone. There are many human variables at play that could slow the pace and magnitude of change – or accelerate it.
Consider the 2.5 billion people who lack access to modern energy resources. This energy poverty means they lack fundamental benefits for illumination, cooking and transportation, and they’re more susceptible to extreme weather disasters. Increased energy access will improve their quality of life – and in some cases their chances of survival – but will increase global energy consumption and possibly hasten warming.
Diffenbaugh said that the range of climate projections offered in the report can inform decision-makers about the risks that different levels of climate change pose for ecosystems.
“There’s no question that a climate in which every summer is hotter than the hottest of the last 20 years poses real risks for ecosystems across the globe,” Diffenbaugh said. “However, there are opportunities to decrease those risks, while also ensuring access to the benefits of energy consumption.”
The Queensland Government has approved the first stage of plans to build a multi-billion-dollar mega resort and casino at Cairns in the state’s far north.
Last night, the State Government declared the Aquis Great Barrier Reef Resort in Cairns a “coordinated project” because of its foreseeable economic benefits for Queensland.
The $4.2 billion project, funded by Chinese billionaire Tony Fung, includes nine luxury hotels, an 18-hole golf course, 25,000-seat sports stadium, and an international class casino to be built at Yorkey’s Knob.
It is expected to create more than 9,000 jobs during construction and 10,000 full-time jobs when operational.
The project will be overseen by the coordinator-general’s office and will now go through a series of environmental and economic checks before construction can begin.
Barron River MP Michael Trout says the proposed resort and casino would put Cairns on the map internationally.
Mr Trout says he has spoken with the developer and trusts the project will be a success.
“It will truly make us an international destination again,” Mr Trout said.
“[The developer] said to me ‘I will do this if the people of Cairns want it, if the people of Queensland want it, and if the governments want it – I will do this’.”
However, Griffith University lecturer Paul Williams says the public should be sceptical about the timing of the announcement.
“Politicians do of course say all sorts of things around election time. but if this does come off – $4.2 billion – these are eye-glazing figures for a single part of Queensland,” he said.
“North Queenslanders should rightly be excited about this.
“This is obviously going to be huge to the region, for tourism, for jobs in general.
“I think north Queenslanders have the right to be excited about this, but at the same time remain sceptical
The loss of sea ice is expected to lead to isolation and increased inbreeding among Arctic foxes, which currently use ice to travel between populations. (Jeff Kerby/Science)
Caribou may be affected by changes in their food sources, as a result of the warming climate, and increased human activity along shipping routes may affect their migration. (Mark Post/Penn State University)The proportion of the Arctic covered by sea ice during the summer 
Polar bears are spending more time on land as the sea ice melts, leading to increased contact with grizzly bears. Interbreeding has created hybrids, such as this one shot on Banks Island, N.W.T., in 2006. (Canadian Press)For example, the loss of ice reduces the fat content of algae that live between layers of ice, making them less nourishing to marine animals, the researchers noted.
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