Feed aggregator

SOCIAL NETWORKS: There is a limit to how many people you can have in your social network - now a study reveals why, and how many relationships you need to maintain that network.

The records keep on falling Thermometer image from www.shutterstock.com

We’re not even halfway through the year but already you may have heard talk of 2016 being the hottest on record. But how can scientists be so sure we’re going to beat the previous record, set just last year?

Even before the end of 2015, the UK Met Office was forecasting with 95% confidence that 2016 would beat the record. Since then, that confidence has grown still further, as record after record has tumbled. April 2016 broke the record for the hottest April after we had experienced the hottest February and March on record already this year.

NASA climatologist Gavin Schmidt recently estimated at least a 99% likelihood of 2016 being hotter than 2015.

The role of El Niño

The main reason why scientists are so sure that 2016 will be the hottest year is El Niño, which is associated with warmer sea surface temperatures in the eastern Pacific Ocean. The 2015-16 El Niño was among the strongest on record and has increased global average temperatures.

Even though the El Niño is now decaying, the second year of a major El Niño event is often associated with much warmer than normal conditions and is typically warmer than the first.

For instance, the 1997-98 El Niño was by some measures the strongest on record, and contributed to 1998 becoming the hottest year on record globally at the time.

Since the start of this year, we have seen global temperature records smashed time and time again. This means that much colder temperatures for the second half of the year would be needed for 2016 not to surpass the 2015 record.

Even a strong La Niña event (the cooler opposite of El Niño), which some analysts are forecasting, is unlikely to produce cold enough temperatures.

One thing that could prevent 2016 becoming a record-breaking hot year is a major volcanic eruption in the tropics. Volcanic eruptions at low latitudes can eject aerosols high into the atmosphere reducing the amount of energy from the sun reaching the Earth’s surface.

Previous eruptions such as Pinatubo in 1991 and Tambora in 1815 (which caused 1816 to be “the year without a summer”) reduced temperatures across much of the globe.

However, it is the year after the eruption that often experiences the most severe cooling, so an eruption would have to be pretty soon and very strong to scupper 2016’s chances of being the hottest year on record.

What about climate change?

The role of climate change is smaller because we’re comparing 2016 with last year (the previous record). Over such short periods of time, the contribution from global warming doesn’t change much.

However, scientists estimated that 2015 was about 1℃ hotter than it would have been without human-caused climate change. As the human influence on the climate has not increased greatly since last year this 1℃ estimate will also apply to 2016.

The highly likely record temperature of 2016 will join the previous 17 record-breaking hot years back to 1937 which were all made more likely due to human-caused climate change (the rising global temperatures were even noticed as far back as 1938).

So even if El Niño is driving the 2016 record, we can say that the temperatures of this year (and indeed the temperatures associated with all the records over the last few years) would be virtually impossible without climate change.

An omen for the future?

We expect 2016 to beat the 2015 record for global average temperature as the decaying El Niño event pushes up surface temperatures.

This year, we’ve already seen devastating events associated with unusually warm temperatures, like the mass coral bleaching in the Great Barrier Reef, which has been largely attributed to human-induced climate change.

In future, we can expect to see more extreme heat events, like we’ve already seen in 2016, impacting society and ecosystems across the world.

And even though 2016 is likely to be the hottest year by some margin, we wouldn’t bet on this record lasting too long. While 2017 is very likely to be cooler due to a possible La Niña, with the strong warming trend the world’s experiencing it’s only a matter of time before we have another record-breaking hot year.

Only if we substantially reduce our greenhouse gas emissions now will we see the benefit of fewer record heat events in the future.

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

Ed Hawkins receives funding from the Natural Environment Research Council (UK).

The fossil fuel industry, fee-hungry lawyers, banks and those that stay silent are profiting from the reef’s destruction. It’s time for them to say no more

It’s the worst crisis ever to hit the Great Barrier Reef and the extent of the devastation is only just coming to light. The reef is in the middle of the worst bleaching event ever seen, with unusually warm water killing as much as half the corals in the northern sections, with the trend set to continue for the next 20 years.

Who’s to blame for this destruction? And which businesses are profiting from the activities that are causing this havoc?

Continue reading...

Refugees are forced to flee conflict zones. They have no other choice unlike most migrants who leave their homes voluntarily to improve living conditions

She spent endless days and nights fleeing a warzone as a tiny child, first on foot through the darkness and then by boat after they shut the borders in her native Sierra Leone.

But when Yarrie Bangurra saw the camp she was supposed to be staying in, she couldn’t understand what it was her family had come to.

Continue reading...

EARLY LIFE: Seaweed-like fossils found in rocks in China dated to around 1.56 billion years ago are the earliest known examples of larger organisms made up of many cells built like our own.

For much of this year, up to 1,700 kilometres of the Murray River has been hit by a serious outbreak of potentially toxic blue-green algae, which has flourished in the hotter-than-average conditions. After three months, the river is now recovering with the arrival of wet weather. But we are unlikely to have seen the last of these poisonous microbes.

Large blue-green algal blooms are a relatively new phenomenon in inland waterways. In 1991 an algal bloom affected more than 1,000 km of the Darling River, the first time such an event had been reported in an Australian river, and one of the few times internationally. It was an environmental disaster, killing livestock and striking a telling blow against Australia’s reputation as a clean, green farming nation.

The response was decisive: a state of emergency was declared, and the bloom ultimately gave rise to significant investment by state and federal governments into freshwater research, particularly in the Murray-Darling Basin.

Why no emergency now?

Fast forward two and a half decades to the latest bloom afflicting the Murray River, one of Australia’s most socially, economically and culturally significant waterways. The past decade has seen four similar blooms on the Murray River: in 2007, 2009, 2010 and now. Yes, they have garnered press attention, but there has not been the same call to arms that we saw when the Darling River was struck in 1991.

It is almost as if such significant environmental events are now simply seen as the new normal. Why the apparent complacency?

The 2007, 2009 and 2010 algal blooms on the Murray River all happened during the Millennium Drought, and hence were probably ascribed to an aberration in the weather. In reality, the situation may have more to do with how we manage water in Australia – particularly during periods of scarcity, such as the one we may well be entering now.

Those three earlier events all started in Lake Hume, a large reservoir in the Murray River’s upper reaches, originally created in the 1930s to help “drought-proof” Australia. All of the blooms began after the water level was drawn down to below 10% of the lake’s capacity. At these low levels, disturbances (such as when transferring water between the Snowy River and Murray River systems) can easily lead to the mixing of warm surface waters (ideal for bloom formation) with nutrient-rich water at the bottom of the reservoir (ideal for feeding the bloom).

The resulting blooms were then released downstream into the Murray River by managed water releases from Lake Hume. The blooms most likely reformed in other constructed water bodies downstream – most notably Lake Mulwala, a shallow reservoir about 250 km along the river from Lake Hume.

Lake Mulwala’s principal purpose is to create hydraulic pressure to allow irrigation water to be diverted into farmland in southern New South Wales and northern Victoria. As a result, its shallow depth and mostly still waters make it an ideal incubator for blue-green algae.

The climate factor

This year’s algal bloom on the Murray River is different. The main blue-green alga in the current outbreak, Chrysosporium ovalisporum, has previously been reported in the river, but generally in very low numbers. It has never before formed a bloom in the Murray River since monitoring began in 1978. But crucially, this species flourishes in very warm temperatures; overseas blooms of this species have occurred when water temperatures reach 26℃.

The other difference between the current and earlier blooms is that, when this year’s event started, Lake Hume was much fuller, at about 30% capacity. So reservoir operation probably had less to do with the bloom’s formation than other factors, such as the climate. Both the maximum and minimum temperatures were consistently above the long-term average during the past few months, as was the amount of sunlight reaching the surface of Lake Hume.

We still do not know exactly what triggered this year’s bloom, but if it was indeed a result of unusually warm temperatures, it is very likely that we will see more blooms of this type in the future.

Are we really ready for recurrent blue-green algal blooms on the Murray River? These blooms come at a significant economic cost: drinking water has had to be specially treated to remove potential toxins, and the bloom has impacted on regional tourism, coinciding with the Labour Day and Easter long weekends. It also hit farmers, who had to get drinking water for their livestock from elsewhere.

More importantly, what do these frequent blooms say about how we manage water in this country – especially as we start to see the impacts of climate change on our environment? Dwindling water could mean more than just drought – it could also fill much of the water that remains with poisonous microbes.

Darren Baldwin has received funding from the Murray-Darling Basin Authority to study blue-green algal blooms in the Murray River , including the current bloom.

Chairman of UN’s joint meeting on pesticide residues co-runs scientific institute which received donation from Monsanto, which uses glyphosate

A UN panel that on Tuesday ruled that glyphosate was probably not carcinogenic to humans has now become embroiled in a bitter row about potential conflicts of interests. It has emerged that an institute co-run by the chairman of the UN’s joint meeting on pesticide residues (JMPR) received a six-figure donation from Monsanto, which uses the substance as a core ingredient in its bestselling Roundup weedkiller.

Professor Alan Boobis, who chaired the UN’s joint FAO/WHO meeting on glyphosate, also works as the vice-president of the International Life Science Institute (ILSI) Europe. The co-chair of the sessions was Professor Angelo Moretto, a board member of ILSI’s Health and Environmental Services Institute, and of its Risk21 steering group too, which Boobis also co-chairs.

Continue reading...

Beautiful places threatened by mass tourism

Thai authorities have closed the celebrated scuba-diving destination to visitors – but it’s not the first ‘honeypot’ site to take such action

Related: Thailand closes 'overcrowded' Koh Tachai island to tourists

The trouble for Koh Tachai was that its beaches were just a little too white, its coral reef too colourful, its marine life too dazzling. Now you can’t go there, because Thai authorities have shut it to tourists – the latest and most drastic response to a booming and increasingly itinerant global population.

Continue reading...

More cycling, better public transport and car bans - cities from Delhi to Zurich are using a range of initiatives to lower traffic pollution and improve health

Paris

Paris bans cars in many historic central districts at weekends, imposes odd-even bans on vehicles, makes public transport free during major pollution events and encourages car- and bike-sharing programmes. A long section of the Right Bank of the river Seine is now car-free and and a monthly ban on cars has come into force along the Champs-Elysées.

Continue reading...

2017 finance bill will set price at €30 a tonne in a bid to stir European action to cut emissions and drive forward the Paris climate agreement

France will set a carbon price floor of about €30 ($33.95) a tonne in its 2017 finance bill as the government seeks to kickstart broader European action to cut emissions and drive forward last year’s landmark international climate accord.

The French government said last month that it would unilaterally set a carbon price floor in the absence of a broader European initiative to strengthen carbon pricing, hoping the move will spur other countries to act. It did not, however, give an indication on pricing.

Continue reading...

Report’s author says City Hall publicised positive conclusions but held back the finding that deprived schools were disproportionately affected by toxic air

The author of a report on how London’s illegal air pollution disproportionately affects deprived schools has said City Hall under Boris Johnson held back the study’s negative findings, while publicising the positive ones.

The Guardian revealed an unpublished Greater London authority (GLA) report on Monday that showed how deprived schools in the capital were disproportionately affected by toxic air, leading the new mayor, Sadiq Khan, to accuse Johnson of burying the report.

Continue reading...

More than 100 of the world’s poorest and most poorly governed countries have no or limited monitoring of the polluted air their citizens are breathing

More than 1 billion people live in countries that do not monitor the air they breathe, according to data released by the World Health Organisation (WHO).

Guardian analysis has revealed a great air pollution blindspot stretching the length of Africa, across large parts of the former Soviet Union, south-east Asia and the Caribbean. In 92 countries the monitoring equipment and staff needed to measure one of the world’s most deadly pollutants - particulate matter (PM) - are simply not available.

Continue reading...

Governments have begun work on implementing the 2015 Paris Agreement to limit global warming.

Our EcoCheck series takes the pulse of some of Australia’s most important ecosystems to find out if they’re in good health or on the wane.

When Europeans first saw Victoria’s native grasslands in the 1830s, they were struck by the vast beauty of the landscape, as well as its productive potential.

The explorer Sir Thomas Mitchell described the western Victorian plains as “an open grassy country, extending as far as we could see … resembling a nobleman’s park on a gigantic scale”. His fellow pioneer John Batman, in 1835, described the grassy plains to the north and west of what is now Melbourne as “the most beautiful sheep pasturage I ever saw in my life”.

Victoria’s volcanic plain, home to a rich variety of wildflowers. Hesperian/IBRA/Wikimedia Commons

The native temperate grasslands of southeastern Australia are a group of ecosystems defined mainly by the presence of dominant native grasses. Trees are either completely absent, or occur in very low numbers.

In Victoria, native grasslands can be found on the volcanic plains that stretch from Melbourne as far west as Hamilton. Despite their rather plain name, native grasslands are extraordinarily diverse, containing many species of wildflowers that grow between the tussocks of grasses.

It is possible to find more than 25 different plant species in a single square metre of native grassland, and the wildflowers produce dazzling displays of colour during spring.

The animals that inhabit these grasslands are equally diverse and fascinating. The striped legless lizard, grassland earless dragon and golden sun moth are three that live there today, although many others are now locally extinct. One can only imagine how impressive it would have been to see brolgas, rufous bettongs and eastern barred bandicoots roaming, nesting and digging on these plains.

Grassland earless dragon. John Wombey/CSIRO/Wikimedia Commons, CC BY

Native grasslands were a significant food source for Aboriginal people. They provided both meat (kangaroos and other grazing animals were attracted to the open grassy landscapes) and vegetables.

Many of the native forb plants produce energy-rich tubers or bulbs that can be eaten much like a potato. These made up a large part of the diet of Aboriginal people living in these areas.

Fire is critical to maintaining the diversity and health of native grasslands, and fire regimes used by Indigenous people are an important aspect of grassland management.

Plains to pasture

The story of Victoria’s native grasslands since European settlement is not a happy one. Grasslands offer extremely fertile land (by Australian standards, at least), which made them attractive for agriculture and grazing. Overgrazing by sheep and cattle, the addition of fertilisers to “improve” pastures, and changes to the frequency and extent of fires in the landscape led to a noticeable degradation of Victoria’s native grasslands by the early 20th century.

Since then, habitat loss and degradation from intensive grazing, cropping and – more recently – urbanisation have reduced the native grasslands of the Victorian volcanic plain to less than 1% of their original extent (as documented in the paper titled “Vegetation of the Victorian Volcanic Plain” available here).

Land clearing for urban development continues to pose a major threat to Victoria’s native grasslands. Many remnants exist in and around Melbourne’s key urban growth corridors.

A 15,000-hectare grassland reserve is planned to the west of the city to offset the losses that will occur as Melbourne grows. This is an exciting prospect – such a large reserve would provide an opportunity to showcase this threatened ecosystem on a landscape-wide scale.

But successful implementation of this reserve requires significant investment in restoration and management, and only time will tell whether it truly compensates for the inevitable losses elsewhere.

Saving what remains

A major challenge for the conservation of Victoria’s native grasslands is to maintain the patches that remain. These remnants, nestled in agricultural and urban landscapes, are often small and fragmented, and are subject to threats such as weed invasion and broad-scale use of herbicides and fertilisers.

Without regular fires or some other form of biomass removal, the native grasses grow too big and smother the wildflowers. Over time, grasslands can lose their species diversity, and with it the intricate beauty of their varied wildflowers.

Redreaming the Plain. Digital composite created for Imagine The Future (ITF) Inc. by Csaba Szamosy, 1996, from photographs by James Ross (Victorian National Parks Association), Mike Martin (Victoria University), Tom Wheller (VNPA), Vanessa Craigee (Department of Natural Resources and Environment), John Seebeck (NRE) and Ian McCann (courtesy NRE/McCann Collection), and based on a concept by Merrill Findlay for ITF.

On the face of it, the prognosis for these grasslands does not look great. They are certainly one of Australia’s most endangered ecosystems, and their conservation must necessarily occur alongside human-dominated land uses. This brings social challenges as well as ecological ones.

Native grasslands suffer from a public relations problem. The need for regular fires is not always well aligned with objectives for human land uses. What’s more, all those wildflowers only appear in season, and even then their beauty is only really evident at close quarters.

But grasslands have a few tricks up their sleeves. First, high-quality grasslands can be maintained in relatively small patches. There are some great examples around Melbourne, including the Evans Street Native Grassland, which covers just 4 hectares. But as tiny as they are, these reserves can be just as diverse as larger grassland remnants.

Second, native grasslands can be surprisingly resilient, in both urban and agricultural landscapes. A case in point is the tiny grassland at the Watergardens shopping centre northwest of Melbourne, which has been maintained despite being completely surrounded by a car park. Several high-quality grasslands in pastoral areas have been maintained for decades under grazing at low stocking rates.

Third, native grasslands represent a great opportunity to engage urban residents with nature in cities. Many beautiful remnants exist in some of Melbourne’s newest suburbs. Some already benefit from the efforts of dedicated community groups, while others are still waiting to be discovered.

Grasslands in other parts of the world, such as North America’s prairies or the African savannah, are viewed with romanticism and awe. In the Australian consciousness, grasslands take a back seat to the mythical outback. But the future of the grasslands of southeastern Victoria may well depend on our capacity to generate the same public profile for this truly remarkable but critically endangered ecosystem.

Are you a researcher who studies an iconic Australian ecosystem and would like to give it an EcoCheck? Get in touch.

Georgia Garrard is supported by funding from the National Environmental Science Programme's Threatened Species Recovery Hub.

Sarah Bekessy receives funding from the Australian Research Council and through the National Environment Science Programme's, Threatened Species and Clean Air and Urban Landscapes Hubs.

Tasmania's hydro power is dependent on rains. Dam image from www.shutterstock.com

Fighting climate change will involve massive changes to the way we produce and distribute energy. Those changes are already happening. Several studies have looked at how our energy systems will change as clean energy increases and fossil fuels are replaced.

But climate change must be planned into this transition.

For instance, temperature is a key driver of demand for electricity, and future increases in heatwaves will probably drive higher electricity demand for air conditioners.

So how could future climate changes affect the ability of the system to generate enough electricity?

Climate and energy

Renewable energy technologies are highly dependent on climate-related factors including sunlight, wind speed and water availability. Water is also a key requirement for coal and nuclear power stations. Heatwaves can impact on the capacity of transmission lines to move energy around the national grid.

The changes to climate in Australia resulting from increased greenhouse gas emissions include more extreme heat events, longer and drier droughts, and longer and hotter heatwaves, as well as stronger storms and rainfall events. Shifts in large-scale circulation patterns may have some impact on wind speed but these effects are less clear.

These climate events and trends affect almost all energy generation and distribution systems, and need to be factored into good management. There is a broad range of intersections between the changing climate and the energy systems of the future that need to be considered.

The future is here

The current mix of generation technologies in the energy system is in a state of flux and undergoing relatively rapid change, as renewable energy, particularly wind turbines and rooftop solar, increase. And the changing climate is already affecting the current energy infrastructure.

Recent years have seen several extreme weather events – with a detectable influence from climate change – that have seriously impacted electricity generation in Australia.

Tasmanian hydro dam levels are currently at record lows. With the Basslink connector also out of action, the shortfall in energy generation is being made up through the use of diesel generators.

Much has been made of this situation already, but the lack of rainfall over the past year is consistent with long-term projections for rainfall in southeast Australia.

In 2014, the Hazelwood mine fire was started by bushfire embers in rural Victoria. It burned for 45 days in the wake of a heatwave that brought temperatures not seen since the extreme heat of 2009.

The 2009 heatwaves themselves shut down the Basslink transformer in Georgetown, Tasmania, reducing the electricity available to Victoria and South Australia. At the same time, two transformers in Victoria failed, leading to supply loss that significantly impacted Melbourne and western Victoria.

In Queensland, the 2010-11 floods caused widespread damage to the electricity network. Substations were flooded, high-voltage feeder lines were damaged and, in the Lockyer Valley, much of the electricity infrastructure was destroyed.

The costs of replacing and repairing electricity networks damaged by extreme weather events can be seen as one consequence of our continuing reliance on fossil fuels.

More variable rain and sun

As the climate changes further, electricity networks will have to manage increasingly variable rainfall – less in southeast and southwest Australia and possible increases in the north.

In 2013, Australia had more than 120 operating hydroelectric power stations, with a total generation of almost 20 terawatt-hours (8% of total energy generated).

Most hydro power is produced at dams on Australia’s major river valleys, and only a few of these have been left untouched. As water availability becomes more uncertain, this type of generation is unlikely to expand much further.

Australia has the highest average solar radiation per square metre of any continent in the world. More than five gigawatts of solar photovolaic panels have been installed, both on rooftops and more recently as large-scale installations.

These panels are prone to extreme weather events, such as hail. Events such as Melbourne’s 2010 storm and Perth’s freak storm the same year could dramatically impact a high-penetration renewable energy system.

Similarly, plans for large-scale solar plants that create steam to drive turbines should take changes to rainfall and available water resources into consideration at the planning stage. Solar radiation is affected by El Niño, with up to 10% less radiation available during La Niña conditions.

Other areas of generation (such as wind, ocean and bioenergy) may also be affected by climate change, as circulation changes result in shifts in wind fields and precipitation patterns (affecting biofuel crop yields).

The likely effects of these changes are much harder to project, but the potential for reduced output needs to be taken into consideration when making plans for future energy systems.

Roger Dargaville receives funding from the Australian Renewable Energy Agency (ARENA).

Jane Mullett receives funding from the Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC-CARE).

The Australian Heritage Council is assessing the Tjoritja/West MacDonnell National Park (including the adjacent Standley Chasm) for potential inclusion on the National Heritage List. Comments close 20 June 2016.

GREAT MOMENTS IN SCIENCE: Not all raw foods are good for you. Dr Karl explains why raw milk is one of the world's most risky food products.

BENDY BATTERIES: Scientists have developed thin, soft stretchy batteries and solar cells that can be applied to the skin like a band-aid.

Some 40 Bruny Island households are to be transformed into ‘mini-power stations’ as they trial Reposit Power’s software and solar storage

There are more than 1.5m households in Australia with rooftop solar. And in a few months time, 40 Tasmanian homeswill be acting as mini power stations – not just producing energy for their own consumption and to export back into the grid, but actively trading and profiting from the power they generate.

Much has been written about rooftop solar and the impending boom in battery storage but the key ingredient to turning homes into mini-power stations is the software that links the hardware of these technologies. Now the Canberra-based startup Reposit Power is helping to change the way households and energy companies think about solar and storage.

Continue reading...