Author: Neville

Nitrogen from Pollution, Natural Sources Causes Growth of Toxic Algae, Study Finds

Feb. 6, 2013 — Nitrogen in ocean waters fuels the growth of two tiny but toxic phytoplankton species that are harmful to marine life and human health, warns a new study published in the Journal of Phycology.

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Researchers from San Francisco State University found that nitrogen entering the ocean — whether through natural processes or pollution — boosts the growth and toxicity of a group of phytoplankton that can cause the human illness Amnesic Shellfish Poisoning.

Commonly found in marine waters off the North American West Coast, these diatoms (phytoplankton cells) of the Pseudo-nitzschia genus produce a potent toxin called domoic acid. When these phytoplankton grow rapidly into massive blooms, high concentrations of domoic acid put human health at risk if it accumulates in shellfish. It can also cause death and illness among marine mammals and seabirds that eat small fish that feed on plankton.

“Regardless of its source, nitrogen has a powerful impact on the growth of phytoplankton that are the foundation of the marine food web, irrespective of whether they are toxic or not,” said William Cochlan, senior research scientist at SF State’s Romberg Tiburon Center for Environmental Studies. “Scientists and regulators need to be aware of the implications of both natural and pollutant sources of nitrogen entering the sea.”

Nitrogen can occur naturally in marine waters due to coastal upwelling, which draws cool, nutrient-rich water containing nitrate (the most stable form of nitrogen) from deeper depths into sunlit surface waters. Pollution, including agricultural runoff containing fertilizer and effluent from sewage plants, is also responsible for adding nitrogen, including ammonium and urea, to ocean waters, but in most regions these types of nitrogen occur at relatively low concentrations.

In laboratory studies, Cochlan and former graduate student Maureen Auro found that natural and pollution-caused nitrogen forms equally support the growth of the harmful Pseudo-nitzschia algae and cause the production of the domoic acid, but in all cases the natural form of nitrogen caused the most toxic cells.

They also found that these small diatoms became particularly toxic under low light levels — a condition that usually slows the growth of phytoplankton. The species, P. cuspidata, underwent an up to 50 fold increase in toxicity under low light levels compared to the conditions that are thought to normally favor phytoplankton growth.

Scientists already know that in some large-celled species of Pseudo-nitzschia their toxicity increases when the cells grow slower, but in previous studies the slowing of cellular growth was due to the limitation of vital nutrients, such as silicate. However Cochlan’s latest study found that the toxicity of these small toxigenic diatoms is affected by the type of nitrogen they consume. He found that under low light levels — leading to slow growth — phytoplankton cells that were fed on naturally occurring nitrate were more toxic than cells that were fed on either urea or ammonium caused by pollution.

“Our results demonstrate that the reason for the growth of these specific harmful algal blooms off the coast of North America from British Columbia to California may in fact be due to totally natural causes,” Cochlan said.

Such toxic algal blooms may be largely supported by the natural upwelling of nitrogen. However, Cochlan cautions that when the pattern of upwelling is weaker, nitrogen from pollution could play an important role in sustaining a “seed population” of harmful algae — a remnant that keeps the bloom going until upwelling resumes and the bloom is able to grow again and perhaps increase their toxic effect on the marine ecosystem.

“This is the first physiological study to look at the environmental conditions that promote both the growth and the toxicity of these small diatoms,” Cochlan said. “The findings may shed light on why these microorganisms produce a potent neurotoxin and what the ecological advantage is for the phytoplankton producing it.”

“Nitrogen Utilization and Toxin Production by Two Diatoms of the Pseudo-nitzschia pseudodelicatissima complex: P. cuspidata and P. fryxelliana,” was published in the February 2013 issue of the Journal of Phycology. The paper was authored by Maureen E. Auro, a graduate of the marine biology master’s program at SF State, and William P. Cochlan, senior research scientist at SF State’s Romberg Tiburon Center for Environmental Studies.

The study was funded by the National Science Foundation’s Ecology and Oceanography of Harmful Algal Blooms program (ECOHAB).

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Pacific Locked in ‘La Nada’ Limbo

Feb. 6, 2013 — Sea-surface height data from NASA’s Jason-1 satellite show that the equatorial Pacific Ocean is still locked in what some call a neutral, or ‘La Nada’ state. This condition follows two years of strong, cool-water La Niña events.

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A new image, based on the average of 10 days of data centered on Jan. 26, 2013, shows near-normal conditions (depicted in green) across the equatorial Pacific. The image is available at: http://sealevel.jpl.nasa.gov/images/latestdata/jason/2013/20130126P.jpg .

This latest image highlights the processes that occur on time scales of more than a year, but usually less than 10 years, such as El Niño and La Niña. These processes are known as the interannual ocean signal. To show that signal, scientists refined data for this image by removing trends over the past 20 years, seasonal variations and time-averaged signals of large-scale ocean circulation.

The height of the water relates, in part, to its temperature, and thus is an indicator of the amount of heat stored in the ocean below. As the ocean warms, its level rises; as it cools, its level falls. Yellow and red areas indicate where the waters are relatively warmer and have expanded above normal sea level, while green (which dominates in this image) indicates near-normal sea level, and blue and purple areas show where the waters are relatively colder and sea level is lower than normal. Above-normal height variations along the equatorial Pacific indicate El Niño conditions, while below-normal height variations indicate La Niña conditions. The temperature of the upper ocean can have a significant influence on weather patterns and climate. For a more detailed explanation of what this type of image means, visit: http://sealevel.jpl.nasa.gov/science/elninopdo/latestdata/ .

“This past spring, after two years of La Niña, the expected El Niño was a no-show,” says Bill Patzert, climatologist at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “La Niña faded and ‘La Nada’ conditions locked in.”

“This absence of El Niño and La Niña, termed ‘neutral’ by some, has left long-range climate forecasters adrift,” Patzert added. “Seasonal, long-range forecasting works best when signals like El Niño and La Niña are strong.” Patzert calls the present condition ‘La Nada,’ because the word ‘neutral’ misleadingly implies to some that weather will be ‘normal.’

“For me ‘normal’ is the cycle on a washing machine,” Patzert said. “I never say the word ‘normal’ when it comes to winter weather in the American West. For instance, in the last 100 years, we’ve only had a total of six ‘normal’ years of rainfall in Los Angeles, meaning about 15 inches of rain per winter in downtown L.A. Historically, La Nadas have delivered both the wettest and driest winters on record. For long-range forecasters, La Nada is a teeth grinder.” NASA scientists will continue to monitor this persistent La Nada — now in its 10th month — to see what the Pacific Ocean has in store next for the world’s climate.

The comings and goings of El Niño, La Niña and La Nada are part of the long-term, evolving state of global climate, for which measurements of sea surface height are a key indicator. Jason-1 is a joint effort between NASA and the French Space Agency, Centre National d’Etudes Spatiales (CNES). Jason-2 is a joint effort between NASA, the National Oceanic and Atmospheric Administration, CNES and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). JPL manages the U.S. portion of both missions for NASA’s Science Mission Directorate, Washington, D.C. In early 2015, NASA and its international partners CNES, NOAA and EUMETSAT will launch Jason-3, which will extend the timeline of ocean surface topography measurements begun by the Topex/Poseidon and Jason 1 and 2 satellites. Jason-3 will make highly detailed measurements of sea level on Earth to gain insight into ocean circulation and climate change.

For more on NASA’s satellite altimetry programs, visit: http://sealevel.jpl.nasa.gov .

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Renewables now cheaper than coal and gas in Australia

By Giles Parkinson on 7 February 2013

A new analysis from research firm Bloomberg New Energy Finance has concluded that electricity from unsubsidised renewable energy is already cheaper than electricity from new-build coal and gas-fired power stations in Australia.

The modeling from the BNEF team in Sydney found that new wind farms could supply electricity at a cost of $80/MWh –compared with $143/MWh for new build coal, and $116/MWh for new build gas-fired generation.

These figures include the cost of carbon emissions, but BNEF said even without a carbon price, wind energy remained 14 per cent cheaper than new coal and 18 per cent cheaper than new gas.

“The perception that fossil fuels are cheap and renewables are expensive is now out of date”, said Michael Liebreich, chief executive of Bloomberg New Energy Finance.

“The fact that wind power is now cheaper than coal and gas in a country with some of the world’s best fossil fuel resources shows that clean energy is a game changer which promises to turn the economics of power systems on its head,” he said.

But before people, such as the conservative parties, reach for the smelling salts and wonder why renewables need support mechanisms such as the renewable energy target, BNEF said this was because new build renewables had to compete with existing plant, and the large-scale RET was essential to enable the construction of new wind and solar farms.

The study also found that Australia’s largest banks and found that lenders are unlikely to finance new coal without a substantial risk premium due to the reputational damage of emissions-intensive investments – if they are to finance coal at all.

It also said new gas-fired generation is expensive as the massive expansion of Australia’s liquefied natural gas (LNG) export market forces local prices upwards. The carbon price adds further costs to new coal- and gas-fired plant and is forecast to increase substantially over the lifetime of a new facility.

BNEF’s analysts also conclude that by 2020, large-scale solar PV will also be cheaper than coal and gas, when carbon prices are factored in.

In fact, it could be sooner than that, as we reported yesterday, companies such as Ratch Australia, which owns coal, gas and wind projects, said the cost of new build solar PV was already around $120-$150/MWh and falling. So much so that it is considering replacing its ageing coal-fired Collinsville power station with solar PV. The solar thermal industry predicts their technologies to fall to $120/MWh by 2020 at the latest.

The Bloomberg analysis said the Australian economy is likely to be powered extensively by renewable energy in future and that investment in new fossil-fuel power generation may be limited.

“It is very unlikely that new coal-fired power stations will be built in Australia. They are just too expensive now, compared to renewables”, said Kobad Bhavnagri, head of clean energy research for Bloomberg New Energy Finance in Australia.

“Even baseload gas may struggle to compete with renewables. Australia is unlikely to require new baseload capacity until after 2020, and by this time wind and large-scale PV should be significantly cheaper than burning expensive, export-priced gas.

“By 2020-30 we will be finding new and innovative ways to deal with the intermittency of wind and solar, so it is quite conceivable that we could leapfrog straight from coal to renewables to reduce emissions as carbon prices rise.” he added.

The analysis by BNEF is significant. Australia relies more on coal than nearly any other industrialised country, but it also has some of the world’s best renewables resources, which it has been slow to exploit. But is this likely to prompt a review of the Coalition’s energy policies – which are based on the premise that renewable energy is expensive and unreliable? Don’t bet on it.

Twenty NASA Balloons Studying the Radiation Belts

Feb. 5, 2013 — In the bright, constant sun of the Antarctic summer, a NASA-funded team is launching balloons. There are twenty of these big, white balloons, each of which sets off on a different day for a leisurely float around the South Pole to collect information about something far more speedy: the rain of particles that can precipitate out of two gigantic donuts around Earth known as the radiation belts.

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The mission — called BARREL (Balloon Array for Radiation belt Relativistic Electron Losses) — is led by Dartmouth College in Hanover, N.H. BARREL works in conjunction with NASA’s Van Allen Probes, two spacecraft currently orbiting around Earth to study the belts, which are also known as the Van Allen Belts. Both the probes and the belts are named after James Van Allen who originally discovered them in 1958.

Together the two missions are trying to track where radiation goes when it escapes the belts — up or down? The charged particles within the belts can damage sensitive electronics on spacecraft like those used for global positioning systems and communications, and can be harmful to humans in space. (The electrons don’t make it all the way to Earth, so pose no danger to those of us on the ground.) The Van Allen Probes are observing how the particles behave in the radiation belts themselves, while BARREL can watch to see how and when the particles course down magnetic fields toward the South Pole. Working together, the two missions will track how the particles move.

“We have daily phone calls from Antarctica with the Van Allen Probes team to coordinate,” says Robyn Millan, the principal investigator for BARREL at Dartmouth. “We look at where their spacecraft are relative to the balloons and make decisions about what data to download from the spacecraft to compare to our data.”

After they’ve launched their 20 balloons, the scientists will go home to analyze the vast amount of BARREL observations and compare it to the information collected by the probes. And then the team will get ready to do the process all over again with 20 more balloons next year.

In addition to Dartmouth, the BARREL mission is supported by scientists from University of California-Berkeley, the University of Washington and University of California-Santa Cruz. Field operations are being conducted at the British research station Halley VI and the South African research station, SANAE IV. In addition to NASA and National Science Foundation support, the campaigns are supported by the National Environmental Research Council in the United Kingdom and the South African National Space Agency (SANSA).

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Blowing Hot and Cold: U.S. Belief in Climate Change Shifts With Weather

Feb. 5, 2013 — A University of British Columbia study of American attitudes toward climate change finds that local weather — temperature, in particular — is a major influence on public and media opinions on the reality of global warming.

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The study, published February 5 by the journal Climatic Change, finds a strong connection between U.S. weather trends and public and media attitudes towards climate science over the past 20 years — with skepticism about global warming increasing during cold snaps and concern about climate change growing during hot spells.

“Our findings help to explain some of the significant fluctuations and inconsistencies in U.S. public opinion on climate change,” says UBC Geography Prof. Simon Donner who conducted the study with former student Jeremy McDaniels (now at Oxford University).

The researchers used 1990-2010 data from U.S. public opinion polls and media coverage by major U.S. newspapers, including The New York Times, Washington Post, The Wall Street Journal and USA Today. They evaluated the relationship between average national temperatures and opinion polls on climate change, along with the quantity and nature of media editorials and opinion pieces related to climate change.

While many factors affect climate change attitudes — political views, media coverage, personal experience and values — the researchers suggest that headline-making weather can strongly influence climate beliefs, especially for individuals without strong convictions for or against climate change.

“Our study demonstrates just how much local weather can influence people’s opinions on global warming,” says Donner. “We find that, unfortunately, a cold winter is enough to make some people, including many newspaper editors and opinion leaders, doubt the overwhelming scientific consensus on the issue.”

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No more ugly panels, solar glass is here

Yahoo!7February 6, 2013, 6:03 pm

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Solar technology on the up

South Australia is harnessing new solar technology, with one business boasting the largest solar facade in the country. Andrea Nicolas reports.

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Thousands across the country are turning to solar panels to save the environment and electricity, but their appearance is often a downfall.

Now one Adelaide business is leading the revolution with a solar panel facade that is virtually unnoticeable.

The black glass that covers the front of the Fullarton Rd building in Adelaide is actually made up of more than 150 high performance solar panels.

“Rather than just putting solar panels on the roof and having the ugly solar panel look, they make it look quite neat,” said solar expert Newman Mundy.

“Australia should really embrace this because in Europe it’s done everywhere, and they have nowhere near as much sun as we do.”

It is the second business in Australia to utilise the new technology.

He told 7News that the darker the window, the more efficient it is, but there is a see-through option available.

“The more power they want, the less transparency they get, and it also comes in wide ranges of colours,” Mr Mundy said.

“It is so cost-effective; it almost costs the same as putting double glazing in.”

While solar window technology is an option for commercial buildings, it would not be viable for residential purposes.

But the industry says new concepts for solar power in the home are in the pipeline.

“We put in a glass solar powered tile, which then replaces an ordinary roof tile,” Mr Mundy said.
He said it would be most cost effective for those building new homes, who haven’t already splashed out on standard building materials.