Feed aggregator

Scientists at Cern have found a new way to unlock the secrets of antimatter.

A deep sea octopod, dubbed Casper after the film ghost, may be at risk from mining, scientists say.

In Darwin the wet season usually arrives around Christmas Day. Storm image from www.shutterstock.com

Christmas in Darwin often means one thing: rain. The north is famous for its wet season, which runs from November to April, when the vast majority of the region’s rain falls.

The flora, fauna and people of the north have adapted to the Australian monsoon and now depend on the arrival of the rain for their survival. Living as we do on an arid continent, it is natural to eye this seasonal source of water as an important resource for agriculture and other economic activity.

But the summer monsoon is also notoriously fickle. Last year’s wet season was the driest since 1992, although there is some evidence that this year will be better. So what drives this important weather phenomenon, and how might it change in the future?

Northern Australia’s wildlife is adapted to the wild swings between wet and dry. Crocodile image from www.shutterstock.com What is the Australian monsoon?

The Australian monsoon actually alternates between two seasonal phases linked to wind direction. In the winter phase, easterly trade winds bring dry conditions. In the summer, westerly winds bring sustained rainy conditions. In fact, the word “monsoon” comes from the Arabic word for season.

Global rainfall daily averages (1979-2008) for the months of January (left) and July (right). The monsoon trough is positioned over northern Australia in the southern summer, and moves northward during the southern winter. NOAA/OAR/ESRL PSD (http://www.esrl.noaa.gov/psd/)

As the summer approaches, the sun heats the Australian land area faster than the surrounding ocean in much the same way as the pavement next to an outdoor swimming pool is heated faster than the pool water.

This difference in heating also produces a difference in pressure, which is lower over the land than the ocean. As a result, warm, moist air from the tropical ocean is drawn towards the lower pressure over the hot and dry north of Australia. It is this increase in humidity in the month or so prior to the sustained rains (known also as the “build-up”) that makes life so uncomfortable for many, driving some people “troppo”.

With increasing humidity, conditions become progressively better for the development of deep clouds and storms.

Eventually, sustained rain, low pressure (the “monsoon trough”) and deep westerly winds become established over land. This transition can be relatively abrupt, and at Darwin usually occurs around Christmas Day, although there is a great deal of variability from year to year.

Satellite image from December 27 2015, showing a tropical low in the Australian monsoon. This weather system contributed to the first big rainfall burst of the 2015/2016 summer monsoon. NASA Worldview (https://worldview.earthdata.nasa.gov/) Why so variable?

Unsurprisingly, El Niño (and its counterpart, La Niña) is partly responsible for the monsoon’s variability.

In El Niño years, the summer monsoon tends to be drier than average, and last year was no exception.

However, El Niño (or La Niña) usually influences only the early part of the season. Once the summer monsoon becomes established, the relationship with El Niño (or La Niña) becomes weaker.

The tropical oceans just to the north of Australia also play a role in the variability. Warmer-than-average sea surface temperatures and greater evaporation have contributed to an early onset of summer monsoon this year by increasing the moisture early in the season.

Rainfall in the Australian summer monsoon occurs in a series of bursts, each of which may last for a few days or weeks. The relatively dry periods between the bursts are referred to as breaks, which can last for lengths similar to bursts. The total amount of rain that falls in a season depends on the intensity of the bursts, their number and their duration.

Daily rainfall averaged over land areas in the north of Australia for the period 1979-2010 (red), and the 2015/16 daily rainfall (blue). Although on average the rainfall over northern Australia is largest between January and February, in any given season the rainfall will occur in sporadic bursts as seen for the 2015/2016 summer monsoon. Bureau of Meteorology (http://www.bom.gov.au/jsp/awap/rain/index.jsp) The science of bursts

One ingredient in rainfall bursts is the envelope of deep clouds known as the Madden-Julian Oscillation (MJO). This eastward-moving atmospheric wave organises deep clouds in the tropics and is often linked to widespread rainfall as it passes over the north of Australia.

This wave has a period (the length of time between rises and falls) of 30 to 60 days, and is closely monitored by the Australian Bureau of Meteorology.

Recent research has shown that a second important ingredient is the mid-latitude troughs (zones of low pressure) that periodically move towards the equator into the tropics. Such troughs rapidly increase the moisture in the monsoon trough and are associated with two-thirds of all bursts.

These influences also work together to produce rainfall bursts in the Australian monsoon.

What about climate change?

The jury is still out on this one, although there are hints as to what might be ahead.

State-of-the-art climate models furiously disagree on whether there will be more or less rainfall and how much more or less in the north of Australia. Although there are reasons to believe that the monsoon regions may become wetter in a warmer world, monsoons pose a challenge for climate models as they depend very strongly on the relationship between the atmosphere, the land and the ocean.

However, recent advances in understanding the role of the mid-latitudes in producing rainfall bursts may help us to untangle some of the uncertainties in the models.

The continuing research into understanding and predicting the Australian summer monsoon will help in planning for the future in this important region.

Sugata Narsey receives funding from the Australian Research Council Centre of Excellence for Climate Systems Science.

Michael Reeder receives funding from Australian Research Council Centre of Excellence for Climate System Science.

Report warning of energy shortage widely discredited after just one MP backs it and it includes misleading claims

A report that warned of Christmas blackouts next year and purported to come from a group of MPs has been discredited after it emerged it was only backed by a single MP and included misleading claims.

The British Infrastructure Group (BIG), chaired by Conservative MP Grant Shapps, published a report on Monday that said coal power station closures and a drive for renewable energy had left the UK facing “intermittent blackouts for the foreseeable future”.

Continue reading...

While some blamed bad weather or predation for beaching at Marazion at St Michael’s Mount, the fish were in fact dumped by a trawler for safety reasons

The mystery of why hundreds of thousands of fish were found washed up on a Cornish beach over the weekend has been solved: they were dumped by a trawler that caught too many sardines in shallow water.

After a photographer happened on the huge shoal of dead fish on Marazion at St Michael’s Mount beach, various explanations were offered for her eerie discovery – just two weeks after a similar sighting on another Cornish beach. Bad weather out at sea and attempts by the fish to escape large predators were both suggested as explanations.

Continue reading...

Scientists say Earth's outer core contains a kind of "jet stream" - a fast-flowing river of liquid iron that is surging westwards under Alaska and Siberia.

Prehistoric pottery shows plants and grains were cooked as early as 10,000 years ago.

Thanet council forced to close beaches for nine days due to ‘catastrophic’ leakage and public health concerns

Southern Water has been fined a record £2m for flooding beaches in Kent with raw sewage, leaving them closed to the public for nine days.

The Environment Agency called the event “catastrophic”, while the judge at Maidstone crown court said on Monday that Southern Water’s repeat offending was “wholly unacceptable”. The company apologised unreservedly, as it did when fined £200,000 in 2013 for similar offences.

Continue reading...

In a year almost certain to be history’s hottest, drastic environmental changes are taking a toll on food supply and even language in Arctic communities

The extreme warmth of 2016 has changed so much for the people of the Arctic that even their language is becoming unmoored from the conditions in which they now live.

The Yupik, an indigenous people of western Alaska, have dozens of words for the vagaries of sea ice, which is not surprising given the crucial role it plays in subsistence hunting and transportation. But researchers have noted that some of these words, such as “tagneghneq” (thick, dark, weathered ice), are becoming obsolete.

Continue reading...

Soaring Arctic temperatures ‘strongly linked’ to recent extreme weather events, say scientists at cutting edge of climate change research

The dramatic melting of Arctic ice is already driving extreme weather that affects hundreds of millions of people across North America, Europe and Asia, leading climate scientists have told the Guardian.

Severe “snowmageddon” winters are now strongly linked to soaring polar temperatures, say researchers, with deadly summer heatwaves and torrential floods also probably linked. The scientists now fear the Arctic meltdown has kickstarted abrupt changes in the planet’s swirling atmosphere, bringing extreme weather in heavily populated areas to the boil.

Continue reading...

A third of Drax’s coal power station will switch to biomass after European commission approves government subsidies

The share price of Britain’s biggest power station operator has jumped to a five-month high after the European commission approved subsidies for its conversion to burn wood pellets instead of coal.

Drax was awarded a renewable energy subsidy contract by the government in 2014 to switch the third unit of its coal power station in North Yorkshire over to biomass. That prompted a state-aid investigation by the commission, which was concerned the estimates of the plant’s performance were too generous and Drax would be overcompensated.

Continue reading...

Other finds in the biodiverse greater Mekong region include a rare banana species from Thailand and a tiny frog from Cambodia and Vietnam

Continue reading...

What’s it like to live among elephants, to know that at any moment you might find yourself face to face with something so awe-inspiring – and so dangerous?

My family and I have lived on the edge of the Mudumalai wildlife sanctuary in the Nilgiri mountains, south India, for over three decades now. The children grew up here. Yet the thrill of knowing there’s an elephant in the garden is a feeling we all still savour. We cherish our elephant memories and can’t ever seem to become blasé about them.

Our elephant adventures began in 1984 when, with our one-year-old daughter, my husband and I crossed the jungle in a dilapidated jeep, sticking behind a lorry for comfort and company. The herds of elephants standing like sentinels on either side of the Bandipur-Mudumalai forest highway had us frantically praying for our safety. Mostly, one elephant, the matriarch, would trumpet loudly, warning us off, especially if there were young calves with the herd. Then she would angrily paw the ground as a prelude to charging. We would race away before she could carry out her threat.

Continue reading...

Originally published in the Manchester Guardian on 23 December 1916

Surrey, December 21
Rabbits could be seen playing in the meadow at the bottom of the down right up to the time when darkness came. There was no evening. The afternoon sky was just tinged with a strip of dull red in the west, and this patch of colour moved a little towards the north; then it died out. Nothing was visible except a planet and a few stars shining faintly, and seemingly very far away. Clouds in the higher sky came and completely blotted them; you lost all sense of direction; a mist began to spread upward; it was only by the tread of grass underfoot you had knowledge of being on the earth at all. The light, cold air died away; there seemed to be nothing but a chill, dead vacancy for almost an hour. Then a rustle, very slight, came moving along low down, as of something creeping over the meadow face. Bending, it was possible to discover that this was but the first movement of a light wind, just playing along the grass and hardly to be felt a few feet above the ground. But before the top of the down could be reached it could be heard sweeping among the elms a few yards on the other side; it had driven off the mist, and the great limbs could just be perceived swaying now this way and now the other. In the bottom, by the farmstead, strangely, a barnyard cock crowed hoarsely and twice, with a long pause in between. After another interval a bantam sounded a long shrill note. The wind dropped. But this morning it was wild again, scurrying heavy rain through the bare hazels. We knew then why the rabbits had been so frolicsome.

Continue reading...

$145 wildlife warning devices are designed to scare devils off road and have limited resale value

Thieves in Tasmania are stealing electronic fence posts designed to save the lives of endangered Tasmanian devils.

The thefts have bewildered the manufacturers, who say the $145 wildlife warning devices serve no purpose other than deterring wildlife and have limited resale value.

Continue reading...

Video footage of the rare Hydrolagus trolli, also known as a chimaera or ghost shark, has been taken for the first time off the coast of California

Continue reading...

Also known as chimaeras, the creatures have tooth plates instead of teeth and a retractable penis on their heads

American scientists surveying the depths of the ocean off the coast of California and Hawaii have unwittingly filmed the mysterious ghost shark for the first time.

The team from the Monterey Bay Aquarium Research Center had sent a remote operated vehicle down to depths of 2,000 metres (6,700ft) when the creature appeared on their screens.

Continue reading...

You couldn’t dream up the crazy set of events that have driven fears that South Australia is a sign of the threats to come to power supply reliability.

The AEMC really needs to get its act together in terms of more forward looking in terms of its approach to modelling.

We've read and reported on some remarkably misinformed analysis in recent weeks, including from country's principal energy rule maker and government's favourite energy consultant. But this one on solar and battery storage just about takes the biscuit.