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Sustainable energy: inside Iceland’s geothermal power plant

The Guardian - Sun, 2016-05-29 16:30
In the first of a series, we visit the Hellisheiði plant, which provides 300MW of power – and Reykjavik’s hot water

Thanks to its position on a volatile section of the Mid-Atlantic ridge, Iceland is a world leader in the the use of geothermal energy, and of the six geothermal power plants in Iceland, Hellisheiði (pronounced “het-li-shay-thee”) is the newest and largest. Fully operational since 2010, it sits on the mossy slopes of the Hengill volcano in the south-west of the country; a green and placid-looking landscape that belies the turbulent geological activity rumbling beneath it.

To access the potential energy under the surface, wells are drilled thousands of metres into the ground, penetrating reservoirs of pressurised water. Heated by the Earth’s energy, this water can be more than 300C in temperature, and when released it boils up from the well, turning partly to steam on its way. At Hellisheiði, the steam is separated from the water to power some of the plant’s seven turbines, while the remaining water is further depressurised to create more steam, used to power other turbines. At its maximum output the station can produce 303MW of electricity, making it one of the three largest single geothermal power stations in the world.

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Women lead the call to arms as anti-fracking fight intensifies

The Guardian - Sun, 2016-05-29 15:55

Female opposition to drilling soars as mothers unite in desire to safeguard children’s future

“We are ready for them,” said Tina Louise Rothery. “It has been a long battle but we have been ready for a confrontation for a long time.”

Rothery is one of a growing group of women at the forefront of opposition to fracking. Of the 250 anti-fracking community groups that have sprung up in Britain in the past few years, very many are led, or strongly backed, by women, who say they have been outraged at plans to risk people’s health by exploiting the countryside for shale gas.

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Eve the Jurassic sea monster

BBC - Sun, 2016-05-29 15:41
Piecing together the bare bones of a sea reptile that swam at the time of the dinosaurs.
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The eco guide to pet fish

The Guardian - Sun, 2016-05-29 15:00

Time to help the creatures that, wrested from habitats where they swim thousands of miles, end up atrophying in tanks

We need to talk about Dory. As Pixar’s charming version of a tropical blue tang swims on to screens in Finding Dory next month, conservationists fear a wave of inappropriate fish buying.

Finding Nemo, which triggered just such a global craze in 2003, posed less of a threat. Clownfish (Nemo’s ilk) are usually bred in captivity for the aquarium trade, but blue tangs are “harvested” from the wild for aquariums, with up to 80% dying during capture and transportation. There is intense pressure on wild populations, especially around coral reefs.

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Alma telescope peers into space

BBC - Sun, 2016-05-29 09:38
Alma telescope peers into space from Chile
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The inconvenient scientists

ABC Environment - Sun, 2016-05-29 08:05
A third of the CSIRO's climate scientists have been sacked. It's part of a radical change in direction at Australia's premier science organisation. Will this leave Australia vulnerable to climate change? Paddy Manning investigates.
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Scientists discover gigantic sea sponge in Hawaii – video

The Guardian - Sun, 2016-05-29 00:46

Deep sea scientists exploring the remote waters between Hawaii and Midway atoll find a gigantic sea sponge “about the size of a minivan” that could be the oldest animal on earth. A remote-operated submersible found the sponge about 2,100m (7,000ft) down, while exploring the depths of the Papahānaumokuākea marine park

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VIDEO: Onboard camera captures rocket landing

BBC - Sat, 2016-05-28 19:53
An onboard camera has captured the successful landing of SpaceX's Falcon 9 rocket, returning from space after launching an Asian communications satellite.
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Construction of world's largest dam in DR Congo could begin within months

The Guardian - Sat, 2016-05-28 18:00

Mega dam on Congo river to produce electricity equal to 20 large nuclear power stations, but critics say it will displace 60,000 people and wreck the ecosystem

The largest dam in the world is set to begin construction within months and could be generating electricity in under five years. But 35,000 people may have to be relocated and it could be built without any environmental or social impact surveys, say critics.

The $14bn (£9.5bn) Inga 3 project, the first part of the mega-project, is being fast-tracked by the Democratic Republic of Congo government will span one channel of the vast river Congo at Inga Falls. It involves a large dam and a 4,800MW hydro-electric plant.

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Solved: the mystery of our absent red squirrels

The Guardian - Sat, 2016-05-28 14:30

Strathnairn, Highlands In all the years we had lived here, we had never had a red squirrel in the garden. This has been the subject of much banter in the village shop

One of the main wildlife mysteries in the strath is the distribution of red squirrels in gardens in the adjoining villages of Farr and Inverarnie. Over many years we have advised people over putting out peanuts and feeders, and every one has succeeded in attracting them. However, one garden of an acre with mature trees and seemingly ideal has not succeeded, and it is ours!

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Tracing Western Australia's pest starlings

ABC Environment - Sat, 2016-05-28 12:53
Western Australia is being invaded by starlings from many sources in the east, not just one in bordering South Australia.
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Maths used to estimate populations of elusive plants and animals

ABC Environment - Sat, 2016-05-28 12:45
Kerrie Mengersen describes her use of mathematics in estimating populations of jaguars and other rare animals in Peru and elsewhere.
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Big solar - Australian sunlight could power the planet

ABC Environment - Sat, 2016-05-28 12:05
Saudi Arabia got rich selling oil. Australia could do the same exporting power from vast fields of solar panels.
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Sea sponge the size of a minivan discovered in ocean depths off Hawaii

The Guardian - Sat, 2016-05-28 11:49

Researchers believe the creature found by scientists 2,100m below the surface of the ocean is the largest of its kind ever documented

Scientists on a deep-sea expedition in the waters off Hawaii have discovered what they say is the world’s largest known sponge.

The creature, roughly the size of a minivan, was discovered about 2,100m (7,000ft) down in a marine conservation area off the shores of the north-western Hawaiian -islands. The rare sponge, with a bluish-white colour and brain-like appearance, stunned scientists when it appeared in the remote cameras attached to their underwater rover.

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How to trap a platypus

ABC Environment - Sat, 2016-05-28 10:30
How to trap a platypus ..with wildlife ecologist, Josh Griffiths.
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How to trap a platypus segment

ABC Environment - Sat, 2016-05-28 10:30
..with wildlife ecologist, Josh Griffiths.
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What is going on with India's weather?

The Conversation - Sat, 2016-05-28 09:11

On May 19, India’s all-time temperature record was smashed in the northern city of Phalodi in the state of Rajasthan. Temperatures soared to 51℃, beating the previous record set in 1956 by 0.4℃.

India is known for its unbearable conditions at this time of year, just before the monsoon takes hold. Temperatures in the high 30s are routine, with local authorities declaring heatwave conditions only once thermometers reach a stifling 45℃. But the record comes on the back of an exceptionally hot season, with several heatwaves earlier in the year. So what’s to blame for these scorching conditions?

Much of India is in the grip of a massive drought. Water resources are scarce across the country. Dry conditions exacerbate extreme temperatures because the heat energy usually taken up by evaporation heats the air instead.

The complex relationship between droughts and heatwaves is an area of active scientific research, although we know a preceding drought can significantly amplify the intensity and duration of heatwaves.

India’s drought was a possible factor in the earlier heatwaves in April over central and southern India. However, Rajasthan, where 51℃ was recorded, is always bone-dry in May. So the drought made no difference to the record temperature.

The El Niño effect

We have also experienced one of the strongest El Niño events on record. While the current event has recently ceased, its sting is certainly still being felt.

El Niño episodes are associated with higher-than-average global temperatures and have also been a factor in some of India’s past heatwaves. However, there is no direct connection to El Niño in Rajasthan, because its climate at this time of year is so dry anyway.

India also has an extreme air pollution problem. Caused largely by domestic fuel and wood burning, it kills up to 400,000 people every year. This pollution, made up of fine particles called aerosols, also has the effect of cooling the local climate by reflecting or absorbing sunlight before it reaches the ground, thus reducing the likelihood of the most extreme high temperatures.

So although India is no stranger to extreme heat at this time of year, the smog has kept record-breaking high temperatures at bay – until now. This is what makes the record in Phalodi remarkable.

Longer-term heat extremes

A study published in 2013 analysed annual trends in extremes and found no significant change in the intensity of extreme Indian temperatures between 1951 and 2010. The high levels of local air pollution were probably behind the lack of change.

However, the study found a significant increase in the frequency of extreme temperatures and a remarkable trend in the duration of warm spells in India, as the map below shows. Warm spells, defined as at least six days of extreme temperatures relative to the location and time of year, increased by at least three days per decade over 1951-2010 – the largest trend recorded globally.

Global trends in ‘warm spell duration index’, which shows that the duration of heatwaves in India has increased markedly relative to the 1961-90 average. Data are also available via www.climdex.org. J. Geophys. Res.

It is worth keeping in mind that these trends are annual and are influenced by extremes all year round. However, monthly trends in the frequency of Indian temperature extremes for May, which can be found on the CLIMDEX climate database, show an increase over the past 60 years.

Based on local station data, the Indian Meteorological Department reported that many northern states experienced an average of eight heatwave days each March-July between 1961-2010. Trends in “normal” and “severe” heatwaves increased over this time, and in particular over the last decade of the analysis.

Some Indian regions also tended towards longer and more intense heatwaves after an El Niño, and northwestern states of India, where Phalodi is located, tend to experience more intense events anyway. Trends in the intensity of extreme temperatures are less clear and vary across the country.

Different spatial and temporal scales and methods of quantifying extreme temperature hamper a direct comparison of the two studies described above. However, they both document an increase in the frequency of extreme temperatures over India, which is consistent with many other regions worldwide. Heatwave indices and the hottest yearly temperature have only increased significantly in a relatively small region of western India.

What will the future bring?

Most climate models do not do a great job of capturing observed trends in heatwaves over India, because large-scale models struggle to accurately represent the localised effect of aerosols.

It is therefore difficult to use them in great detail for future projections, particularly if pollution levels continue or even increase. However, if air pollution is reduced, temperatures will rise with a vengeance. We know this from experience over Europe, where summer temperature trends were virtually zero up to the 1980s and very strong afterwards, once air pollution was controlled.

Even though this is the hottest time of the year for the region, the recent weather should not be dismissed as regular. It is feasible that India’s pollution problem has been “hiding” extreme heat spikes.

While any clean-up activities will have many positive local health impacts, these are likely to cause more intense heatwaves in future. This will be amplified by background warming due to climate change, which is also likely to drive increases in the frequency of temperature extremes.

Last year India and neighbouring Pakistan suffered similarly atrocious conditions, killing thousands of people. This year’s death toll is already over 1,000, with numbers sure to rise further.

India is already highly vulnerable to the health impacts of oppressive heatwaves and, as climate change continues, this vulnerability will grow. It is therefore imperative that heat plans are put in place to protect the population. That’s a difficult prospect in places that lack communications infrastructure or widespread access to air conditioning.

In the longer term, this episode shows that the global warming targets agreed in Paris have to be taken seriously, so that unprecedented heatwaves and their deadly impacts don’t become unmanageable in this part of the world.

The Conversation

Sarah Perkins-Kirkpatrick receives funding from the Australian Research Council.

Andrew King receives funding from the ARC Centre of Excellence for Climate System Science.

Geert Jan van Oldenborgh receives funding from the following projects: European Climate Extremes: Interpretation and Attribution (EUCLEIA), and World Weather Attribution (WWA).

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The Simpson Desert drive

ABC Environment - Sat, 2016-05-28 08:45
Tips for a journey through the red centre of Australia
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Cooling technologies become red hot

BBC - Sat, 2016-05-28 06:23
Sainsbury's is trialling new food-cooling technologies that promise to be more eco-friendly than current alternatives.
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VIDEO: Ice blocks make fridges less 'stupid'

BBC - Sat, 2016-05-28 06:22
Roger Harrabin visits a factory in Wales that is using ice to make fridges more economical.
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