Satellites above the Earth are documenting a striking change in the Arctic. Not only is open water area increasing in the region, but adjacent land areas are growing “greener.” Since observations began in 1982, Arctic-wide tundra vegetation productivity has increased. In North America, the rate of greening has accelerated since 2005.
One of NOAA’s satellite remote sensors—the Advanced Very High Resolution Radiometer (AVHRR)—collects images of our planet’s surface, which scientists use to carefully measure the intensity of visible and near-infrared sunlight reflected by plants back up into space. From these measurements, they are able to determine the density of vegetation, or “greenness,” on land.
Continue reading 2013 Arctic Report Card: Greener Arctic of recent years likely to be the new normal
A team of international researchers, led by Monash University’s Associate Professor Wouter Schellart, have developed a new global map of subduction zones, illustrating which ones are predicted to be capable of generating giant earthquakes and which ones are not.
Global map showing the location of the active subduction zones. Subduction zones have been divided into ∼200 km segments as indicated by the colored line segments. Color indicates the maximum subduction zone thrust earthquake recorded in that segment in the period 1900–June 2012. For a large number of segments a focal mechanism has been plotted as obtained from the GCMT catalog or from
Continue reading Global map to predict giant earthquakes
Scientists have determined the magnitude of the Mount Gambier volcano eruption 5,000 years ago, and say if a similar eruption occurred again, it could cause widespread damage.
Detailed in the Bulletin of Volcanology, researchers from Monash University’s Volcanology Research Group (MONVOLC) used 3D geometrical computer modelling and thermodynamics – the study of the relationship between different forms of energy – to determine the size and magnitude of the Mount Gambier eruption.
It is believed to be the first time the magnitude and size of a volcano on Australian mainland has been calculated, based on volume estimates of the volcanic deposits, and modelling of the volcanic
Continue reading New clues to prehistoric eruption
With no access to modern navigation instruments, Vikings relied on birds, whales, celestial bodies, chants and rhymes to navigate the seas and discover new land.
Today it seems like a bit of a mystery how our savage forefathers managed to navigate their way across the Atlantic centuries before Columbus discovered America.
During the Viking Age, people started to categorise ships according to their functions. There were two types. One was primarily suitable for transporting armed men. The other was suitable for transporting cargo. Pictured here is the Viking Ship Museum’s freighter Ottar, which is of the type that was used for navigating the North
Continue reading How Vikings navigated the world
This shows details of the flowers of Hochstetter’s Butterfly-orchid, a newly recognized and exceptionally rare orchid recently discovered on the Azorean island of São Jorge.
Credit: Richard Bateman
Researchers studying speciation of butterfly orchids on the Azores have been startled to discover that the answer to a long-debated question “Do the islands support one species or two species?” is actually “three species”. Hochstetter’s Butterfly-orchid, newly recognized following application of a battery of scientific techniques and reveling in a complex taxonomic history worthy of Sherlock Holmes, is arguably Europe’s rarest orchid species. Under threat in its mountain-top retreat, the orchid urgently requires conservation recognition.
Continue reading Europe’s rarest orchid rediscovered on ‘lost world’ volcano in the Azores
Scientists able to study a photosynthetic complex – arguably the most important bit of organic chemistry on the planet – in its complete functioning state When sunlight strikes a photosynthesizing organism, energy flashes between proteins just beneath its surface until it is trapped as separated electric charges. Improbable as it may seem these tiny hits of energy eventually power the growth and movement of all plants and animals. They are literally the sparks of life.
The three clumps of protein — a light-harvesting antenna called a phycobilisome and photosystems I and II — look like random scrawls in illustrations but this is misleading. They are
Continue reading Scientists stitch up photosynthetic megacomplex
Fertile land is scarce in Egypt. All of life depends on water from the Nile River. 85 million Eyptians are settled along its banks. The rest of the country is desert. Egyptian and German scientists have now found a way of cultivating forests in the desert sand.
It looks like a fata morgana. But the forests in the Egyptian desert are real. They’re watered with processed sewage. 24 such forests have sprung up across the country over the past eight years. The sewage is rich in nutrients and fuels the growth of plants like mahagony, eucalyptus and sisal.
A Report by Florian Nusch
Continue reading Egypt: The Amazing Forest in the Desert
Brain research by UH biologists provides new clues to Pavlovian conditioning
Do fruit flies hold the key to treating dementia? Researchers at the University of Houston (UH) have taken a significant step forward in unraveling the mechanisms of Pavlovian conditioning. Their work will help them understand how memories form and, ultimately, provide better treatments to improve memory in all ages.
Gregg Roman, an associate professor of biology and biochemistry at UH, and Shixing Zhang, his postdoctoral associate, describe their findings in a paper titled “Presynaptic Inhibition of Gamma Lobe Neurons Is Required for Olfactory Learning in Drosophila,” appearing Nov. 27 in Current Biology, a scientific
Continue reading New clues to memory formation may help better treat dementia
The decrease in snowfall observed in recent years in Canada’s subarctic regions has led to worrisome desiccation of the regions’ lakes. This is the conclusion arrived at by researchers from Université Laval, Wilfrid Laurier University, Brock University and the University of Waterloo in a study published this week on the website of the scientific journal Geophysical Research Letters.
Caption: Desiccated lakes in Wapusk National Park near Churchill, Manitoba (Canada) are shown. Desiccation of shallow lakes has occurred recently in response to lower-than-average snowmelt runoff. This phenomenon appears unprecedented over the last 200 years.
Credit: Hilary White
Researchers came to this conclusion after studying 70
Continue reading Subarctic lakes are drying up at a rate not seen in 200 years
Researchers have shown that a single monomer of the protein tau can be enough to kick-start an aggregation process which may explain the onset of Alzheimer’s in the brain.
Left: Neuronal cells have ingested Tau protein, which appears in green (scale bar: 10 μm). Right: Optical super-resolution microscopy reveals that ingested protein (red) causes internal protein (green) to form fibrillar aggregates (scale bar: 500 nm).
Credit: Clemens Kaminski.
A powerful laser imaging technique has been used by researchers to show how minute quantities of a protein associated with Alzheimer’s Disease trigger a process which may be crucial to its onset and spread.
Continue reading Protein released from cells triggers chain reactions that could cause Alzheimer’s disease