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事实上，大象已经濒临灭绝
目前全球大象种群处境危急。卡尔·马蒂森 就将向我们解释，为何大象即将迎来前所未有的生死攸关时刻。
翻译: Estelle/中外对话/chinadialogue
作为陆地上体积最大的野生动物，声音如雷、体重可达六吨的大象可谓是生物演化史上的一个奇迹。除了它们那有着10万块肌肉的灵活无比的鼻子，和能帮助它们驱走热量的特大号耳朵之外，大象族群还有着复杂的母系社会结构，它们甚至还会在同伴逝去之后恸哭哀痛。而大象的另外一个特征就是长长的象牙，这本来应该是它们保护自己的防卫武器，然而却最终成为了族群濒危的导火索。
Continue reading...Overview: a stunning new perspective of Earth from space – in pictures
The overview effect is the transformative experience astronauts feel on seeing Earth from space and mankind’s place and impact upon it. Images from a new book, Overview: A New Perspective, by Benjamin Grant display the beauty and fragility of our planet and its natural resources
Continue reading...Hundreds of key sites in England at risk of floods
Flooding: UK government plans for more extreme rainfall
National review prompted by severe flooding in recent winters anticipates 20-30% more extreme downpours than before
The UK’s new flood defence plans anticipate significantly higher extreme rainfall, after new research was published as part of the government’s National Flood Resilience review.
The government, which had been criticised for not taking full account of the impact of climate change in driving up flood risk, will now plan for 20-30% more extreme downpours than before.
Continue reading...Climate change and other human activities are affecting species migration | John Abraham
Humans have an impact on species migration both through climate change and by changing the landscape.
One of the reasons climate change is such an important topic is that it will affect (and already is affecting) the natural biological systems. Both plants and animals will have to respond to the changing climate. In some cases, this means adapting to higher temperatures. In other cases, the changes may be alterations in the precipitation, length of growing season, availability or resources, or other influences.
While some animals can adapt, others will have to migrate. Obviously migration can be apparent in mobile animals that will move to maintain a more or less similar climate to that to which they are accustomed.
Continue reading...Astronomers search for the vanishing star
Brexit is 'opportunity to rethink flood protection'
Former floods minister Richard Benyon says leaving EU will allow UK to pay farmers to hold back flood water
Farmers could to be paid to hold back flood water under a post-Brexit rural payments system, according to former floods minister Richard Benyon.
Speaking before Thursday’s publication of the government’s report into the response to flooding in Cumbria, Lancashire and Yorkshire last December, Benyon predicted that more resources would be made available.
Continue reading...Beauty and power: how Norway is making green energy look good
On the edge of a forest in northern Norway, an unusually handsome hydroelectric plant is generating a buzz
Ovre Forsland is a big departure from the hulking power stations that traditionally served our energy needs. It looks more like an elegant, custom‑built home from TV show Grand Designs.
Located in the Helgeland district in northern Norway, it’s a small hydroelectric power station capable of supplying 1,600 homes with power.
Continue reading...DNA confirms cause of 1665 London's Great Plague
How rail-to-trail cycling projects are proving their worth
Around the UK, abandoned railway lines are being turned into world-class cycling and walking trails that are boosting local tourism and recreation
When the time came for my family’s first ever multi-day cycle tour, the Devon coast-to-coast ticked all the boxes. The 102-mile route, from Ilfracombe in the north to Plymouth in the south, is 70% traffic-free and passes through some beautiful landscapes.
We began in Barnstaple, rolling along the salt marshes of the river Torridge, up to Dartmoor and down thegorges of the Plym valley. The gradients are gentle as the route follows the path of a series of disused railway lines. I soon realised the easy riding belied the huge challenges of turning a series of abandoned railway lines into a world-class cycling and walking trail.
Continue reading...New hope for solar towers as South Aust. seeks energy competitors
Renewables are getting cheaper all the time – here's why
Connecting renewable energy across Australia will help generate reliable electricity. Wind farm image from www.shutterstock.comThe stars are aligning for Australia to transition to 100% renewable electricity. Our fossil fuel infrastructure is ageing, which means we will soon need to invest in new power generators. New technologies such as battery storage could revolutionise long-standing business models. With care, the transitions away from fossil fuels could offer greater job opportunities.
Our latest research, which corroborates previous work, shows the technology already exists to solve many of the remaining questions around technological capability. For instance, the fact that wind and solar don’t generate electricity when the wind isn’t blowing and the sun isn’t shining can be dealt with by installing a network of diverse generators across a wide area, or by increasing our use of energy storage.
One of the biggest remaining barriers to transition is cost. But this is also rapidly changing. Much work is going into reducing the cost of renewable energy, including the latest funding announcement from the Australian Renewable Energy Agency (ARENA) of A$92 million for 12 solar projects.
The cost of building renewable energyThe cost of renewable energy is highly variable across the world and even within Australia. The picture is not simple, but it does help to start by looking at the big picture.
Average capital costs of constructing new wind, solar PV and ocean/tidal generators are already lower than equivalent coal generation infrastructure.
Research suggests that, overall, the cost of moving to 100% renewable energy is not significantly higher than the cost of hitting a lower target.
The capital cost of investment in renewable energy generation technologies is also falling rapidly. In its 2014 report on global renewable power generation costs, the International Renewable Energy Agency (IRENA) showed that the total cost of installation and operation over a lifetime of small-scale residential PV systems in Australia has fallen from US$0.35 to US$0.17 per kilowatt-hour between 2010 and 2014.
In part this has been because of reduced installation costs, together with our exceptional abundance of sunshine.
As a result, Australian new residential solar installation has soared to the fifth highest in the world. Installed capacity accounts for 9% of national electricity generation capacity and 2.8% of electrical energy generation.
The historical reductions in installation costs for wind energy are similar globally and in Australia. Recent 2016 reverse auctions in the Australian Capital Territory have received Australia’s lowest known contract price for renewables with bids at A$77 per megawatt-hour.
Beyond buildingBut the capital cost of building generation infrastructure is not the whole story. Once the generator is built, operations and maintenance costs also become important. For most renewables (biomass excluded) the fuel costs are zero because nature itself provides the fuel for free.
Other costs that we must consider are variable and fixed costs. Fixed costs, such as annual preventative maintenance or insurance, don’t change with the amount of electricity produced. Variable costs, such as casual labour or generator repairs, may increase when more electricity is produced.
The variable costs for some renewables (biomass, hydropower and large-scale solar PV) are lower than coal. For other renewable technologies they are only slightly higher. Fixed costs for almost all renewable technologies are lower than for coal.
We also need to think about costs beyond individual generators. The vastness of our Australian continent is a bonus and a challenge for building 100% renewable energy.
It can be used strategically to give a 100% renewables supply reliability by using an interconnected network of generators. For instance, it may be very sunny or windy in one region. Excess electricity produced in this region can fill a gap in electricity demand in less sunny or windy places elsewhere.
But this also poses challenges. To take advantage of the reliability that a highly distributed renewable electricity system can provide, we must also consider the costs associated with expanding the transmission network.
For example, in our research we investigated one possible 100% renewables electricity scenario. This was conservatively based on current technology and demand (conservative because technology is likely to change, and electricity demand has been unexpectedly falling). The scenario required a transmission grid two-and-a-half times larger than our current grid, including new cross-continental linkages between Western Australia and the Northern Territory, which currently stand alone from the well-integrated eastern Australian networks.
The challenges of transitioning to a renewable electricity sector are no doubt great, but our ageing generator infrastructure means that an overhaul will soon be due. Even though the price of electricity from old coal power plants is currently cheaper than that from many new renewable plants (because the former are already paid off), cost reductions mean a strong business case now exists for renewable technologies investment.
In a recent article on The Conversation, John Hewson wrote that “renewable energy is one of our most ‘shovel ready’ business opportunities”.
Now is the time to pre-empt the looming deadline for infrastructure overhaul to ensure future economic resilience for Australia.
Bonnie McBain does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.
London zoo ants at war - archive, 8 September 1924
8 September 1924: Short, fierce campaign between two colonies of ants
Two colonies of ants at the Zoological Gardens, London, last week attracted some attention by the announcement that a decisive war was about to take place between them. The colony referred to as the Left had recently been deposited in the insect-house, and there were indications that the older colony, called the Right, would attempt to wipe it out, as they had wiped out other intruders.
On inquiry at the Zoological Gardens on, Saturday, the “Sunday Times” learned that most of the decisive fighting had now taken place and the Left Army would certainly be the victors.
Continue reading...Relic of a long-gone medieval community
Madingley, Cambridge The hall’s owners desired an estate with a view, and that did not include a village street, so the people were evicted
A time-travelling Tudor peasant might return to the place of their birth and find reassurance in the sight of Madingley’s medieval church. They could stand before its sturdy tower and run their fingers over stones embedded in mortar, as I did, then step inside to rediscover the font where they were baptised, and look up for re-acquaintance with exquisitely detailed medieval figures floating in stained glass.
But a hard stare into the nettled field beside the churchyard would make them wonder where their village had gone. The 18th century owners of Madingley Hall, which is about four miles from the centre of Cambridge, desired an estate with a view, and that view did not include a village street. So by the middle of the century the people had been evicted from their homes, their houses razed to the ground. I came to search for evidence of this lost community and found it.
Continue reading...Large-scale solar to triple after what could be Arena's final renewable energy grants
Greens urge Labor to oppose $1bn cut to Australian Renewable Energy Agency, removing its future capacity for grants
A giant surge of investment in renewable energy has been sparked by what might be the last grants made by the Australian Renewable Energy Agency, as the parliament is poised to cut most of its funding.
Large-scale solar will triple in size, with Arena today announcing the 12 winners of its $92m in grants, which together leverage more than $1bn investment from private companies.
Continue reading...Amitav Ghosh: 'climate change is like death, no one wants to talk about it'
The author’s new book on climate change questions why the arts have been largely silent on the issue and says India must do more reduce its emissions
Speaking at a literary festival in Bhutan, the Indian novelist Amitav Ghosh recently predicted that Himalayan regions, for no fault of their own, will face a catastrophe as climate change takes hold. So chilling was Ghosh that the local paper reported – only half in jest – that a disturbed audience had to be soothed by a subsequent talk by Buddhist monks.
Ghosh, best known for his historical novels, has been travelling the world talking about his new book, The Great Derangement: Climate Change and the Unthinkable, born out of a series of lectures at the University of Chicago.
Continue reading...Carmichael coalmine appeal says Adani 'misled' Native Title Tribunal over benefits
Wangan and Jagalingou people say judge should have found company ‘misled’ tribunal over jobs and economic impact of mine
A traditional owner of the site of Adani’s proposed Carmichael mine has vowed to keep fighting the project as he lodged an appeal from a federal court ruling that endorsed the state government’s approval of the mining leases.
Adrian Burragubba, who speaks on behalf of members of the Wangan and Jagalingou people, who oppose the mine, lodged an appeal to the full bench of the court on Thursday.
Continue reading...CSIRO launches new hybrid energy technology R&D hub
Pollinate wins new investment towards lighting up Indian slums with solar
Origin seeks to build major portfolio of large scale solar plants
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