By reacting with seawater, CO2 increases the water’s acidity, which may significantly reduce the calcification rate of such marine organisms as corals and mollusks.

 The extent to which human activities have raised the surface level of acidity, however, has been difficult to detect on regional scales because it varies naturally from one season and one year to the next, and between regions, and direct observations go back only 30 years.

 SeaThe team of climate modelers, marine conservationists, ocean chemists, biologists and ecologists, led by Tobias Friedrich and Axel Timmermann at the International Pacific Research Center, University of Hawaii at Manoa, came to their conclusions by using Earth system models that simulate climate and ocean conditions 21,000 years back in time, to the Last Glacial Maximum, and forward in time to the end of the 21st century.They studied in their models changes in the saturation level of aragonite (a form of calcium carbonate) typically used to measure of ocean acidification.

 As acidity of seawater rises, the saturation level of aragonite drops. Their models captured well the current observed seasonal and annual variations in this quantity in several key coral reef regions.

 Today’s levels of aragonite saturation in these locations have already dropped five times below the pre-industrial range of natural variability. For example, if the yearly cycle in aragonite saturation varied between 4.7 and 4.8, it varies now between 4.2 and 4.3, which – based on another recent study – may translate into a decrease in overall calcification rates of corals and other aragonite shell-forming organisms by 15 percent.

 Given the continued human use of fossil fuels, the saturation levels will drop further, potentially reducing calcification rates of some marine organisms by more than 40 percent of their pre-industrial values within the next 90 years.“Any significant drop below the minimum level of aragonite to which the organisms have been exposed to for thousands of years and have successfully adapted will very likely stress them and their associated ecosystems,” said lead author Postdoctoral Fellow Tobias Friedrich.“In some regions, the man-made rate of change in ocean acidity since the Industrial Revolution is hundred times greater than the natural rate of change between the Last Glacial Maximum and pre-industrial times.“When Earth started to warm 17,000 years ago, terminating the last glacial period, atmospheric CO2 levels rose from 190 parts per million (ppm) to 280 ppm over 6,000 years. Marine ecosystems had ample time to adjust. Now, for a similar rise in CO2 concentration to the present level of 392 ppm, the adjustment time is reduced to only 100 – 200 years.”

On a global scale, coral reefs are currently found in places where open-ocean aragonite saturation reaches levels of 3.5 or higher. Such conditions exist today in about 50 percent of the ocean – mostly in the tropics.

By end of the 21st century this fraction is projected to be less than 5 percent. The Hawaiian Islands, which sit just on the northern edge of the tropics, will be one of the first to feel the impact.“Our results suggest that severe reductions are likely to occur in coral reef diversity, structural complexity and resilience by the middle of this century,” said co-author Professor Axel Timmermann.

The study has been published in the online issue of Nature Climate Change.

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Researchers have since long supposed that wandering asteroids might seldom approach earth close enough to get snagged by gravity and become temporary moons.

 Mikael Granvik of the University of Helsinki in Finland and colleagues ran computer simulations of the abundance of asteroids of various sizes in Earth’s neighbourhood and the likelihood of their capture in a close encounter, New Scientist reported.

An object must start off in an orbit almost identical to earth’s in order to be captured. This implies that the asteroids are travelling at more or less the same speed as earth, making it feasible for them to get held-up by earth’s gravity, helped by gravitational pulls from the sun and moon. Similar perturbations ultimately shake them loose.

The team estimated that, on average, one asteroid about 1 metre across is in Earth’s orbit at any given time, and 1000 or so smaller space rocks down to 10 centimetres across should be in orbit too.

“There’s a lot more of these than people may have been thinking,” Granvik said.

They orbit at distances between five and 10 times as distant from Earth as the moon. Majority of them stay in orbit for less than a year, however some stay for much longer durations. One of the objects in the team’s simulations stayed in orbit for nearly 900 years.

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Santiago: Researchers in Chile released a series of time-lapse photos  showing the dramatic retreat of a glacier in Patagonia.The Jorge Montt Glacier is shrinking faster than any other in Chile, with its snout retreating 1 kilometer (more than a half mile) between February 2010 and January 2011, glaciologist Andres Rivera said.

Rivera said that global warming is a factor and that the glacier also is melting especially quickly because it partly rests in the waters of a deep fjord.

Researchers presented a video showing the glacier’s yearlong retreat through a total of 1,445 time-lapse photos. It’s one of various similar projects by researchers around the world documenting the loss of glaciers.Rivera has studied dozens of glaciers as a researcher at the Center of Scientific Studies in Valdivia, Chile. He said he and his colleagues didn’t know how rapidly the glacier was shrinking until they put up two cameras with solar panels to charge the batteries and programmed them to shoot four frames a day.”It was more or less clear that this was one of those retreating most quickly. But we didn’t expect in the year of working with these cameras that it would retreat a kilometer more. That was a surprise,” Rivera said in a telephone interview. “This glacier is filled with surprises for us.”

The glacier is about 1,800 kilometers (1,100 miles) south of Santiago in the Southern Patagonian Ice Field, which blankets a wide swath of the Andes between Chile and Argentina.”Patagonia has experienced climate changes at levels much more moderate than those observed in the rest of the world,” Rivera said at a news conference. “However, almost all the glaciers of the region have lost area, and Jorge Montt is the one that has the record retreat.”

The researchers believe that based on a map from 1898, this glacier has retreated roughly 12 miles (19.5 kilometers) since then, Rivera said.It is a tidewater glacier that calves and releases icebergs as it advances into the fjord.”Such glaciers typically do retreat in response to warming. But the speed of the retreat is controlled by the ability of icebergs to break off in the fjord, not by the rate of warming,” said Richard Alley, a prominent glaciologist at Penn State University.Rivera agreed, saying that he thinks climate change is the key trigger and that local conditions at the glacier are also having a big impact. He said his team measured the fjord’s depth at about 1,300 feet (400 meters) in places, which was considerably deeper than they had thought.The retreat rate of the glacier “is quite exceptional,” said Michel Barer, a researcher at McGill University in Montreal who has studied the melting of Peruvian glaciers.

Barer and other glacier experts at a conference of geophysical scientists in San Francisco said the fastest retreating mountain glaciers are probably somewhere in South America or maybe the Himalayas.”We see steady but accelerating retreat of glaciers” in the tropical Andes, Barer said. His calculations show that those glaciers are losing 1 percent of their water a year.

According to a recent study by British and Swedish scientists who analyzed about 350 glaciers in Patagonia, all but two of the glaciers have receded significantly since the late 1800s and have been shrinking at a faster rate during the past three decades. The study was published in April in the journal Nature Geoscience.Neil Glasser, a British glaciologist and one of the authors of the study, said he has also noticed in satellite images over the years that the Jorge Montt Glacier has been shrinking unusually quickly.”We know that many glaciers in South America are retreating, but this one is retreating ten times faster than the land-based glaciers. It shows how sensitive calving glaciers are to warming atmospheric (conditions) and ocean waters,” Glasser said.He said other tidewater glaciers have quickly retreated in places such as Alaska and Greenland, but the Chilean glacier is one of the best examples in South America.Patagonia’s mountain glaciers are so colossal, and fed by so much snowfall each winter, that scientists believe they aren’t in immediate danger of vanishing in the coming centuries.But elsewhere, scientists expect glaciers to dwindle.

Western Canada, for instance, is losing its mountain glaciers and many of them are likely to disappear in the next century, said Garry Clarke, a professor of Earth Sciences at the University of British Columbia.

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 Researchers at the California Institute of Technology (Caltech), surveyed about 300 stars, and focussed on those dubbed “retired” A-type stars that are more than one and a half times more massive than the sun.These stars are just past the main stage of their life hence, “retired”, and are now puffing up into what’s called a subgiant star.“It’s the largest single announcement of planets in orbit around stars more massive than the sun, aside from the discoveries made by the Kepler mission,” John Johnson, first author on the paper, said.The Kepler mission is a space telescope that has so far identified more than 1,200 possible planets, though the majority of those have not yet been confirmed.

To look for planets, the astronomers searched for stars of this type that wobble, which could be caused by the gravitational tug of an orbiting planet. By searching the wobbly stars’ spectra for Doppler shifts, the lengthening and contracting of wavelengths due to motion away from and toward the observer, the team found 18 planets with masses similar to Jupiter’s.|According to Johnson, this new bounty marks a 50 percent increase in the number of known planets orbiting massive stars and, provides an invaluable population of planetary systems for understanding how planets, and our own solar system, might form.The researchers say that the findings also lend further support to the theory that planets grow from seed particles that accumulate gas and dust in a disk surrounding a newborn star.

According to this theory, tiny particles start to clump together, eventually snowballing into a planet. If this is the true sequence of events, the characteristics of the resulting planetary system like the number and size of the planets, or their orbital shapes will depend on the mass of the star.In another theory, planets form when large amounts of gas and dust in the disk spontaneously collapse into big, dense clumps that then become planets. But in this picture, it turns out that the mass of the star doesn’t affect the kinds of planets that are produced.

So far, as the number of discovered planets has grown, astronomers are finding that stellar mass does seem to be important in determining the prevalence of giant planets.The newly discovered planets further support this pattern, and are therefore consistent with the first theory, the one stating that planets are born from seed particles.“It’s nice to see all these converging lines of evidence pointing toward one class of formation mechanisms,” Johnson added.

The study has been recently published in The Astrophysical Journal Supplement Series.

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DURBAN

The latest weather data highlight the conundrum of the negotiations as governments spar on whether developed or emerging countries should bear the brunt of emission reductions. Few attendees expect a breakthrough on the talks, which come amid growing warnings about the likelihood and severity of global warming.

The U.N. weather group said 2011, still with one month left, was the 10th warmest year on record. While the temperature was down from 2010, the WMO said it was higher than previous La Nina years. La Nina typically has a cooling influence on temperatures.Representatives from 192 countries plus the European Union are meeting in Durban, South Africa, for the U.N.-sponsored COP17 climate change talks in order to negotiate what to do as the commitment period under the Kyoto Protocol expires in 2012. So far, the signs are that the old dividing lines between developed and developing countries linger, leading many to have low expectations for the outlook of the agreement.

Attendees are also sparring over $100 billion for a Green Climate Fund that is supposed to support the poorer countries in their efforts to reduce carbon emissions and to combat the effects of changing weather patterns.Participants continued to lay out their positions.”Without consensus the whole international system on climate would be placed in peril,” said Sue Wei, the deputy of the Chinese climate negotiating team.

Sue also said China wasn’t on board with an EU proposal to formulate a new agreement that would legally bind all countries to cutting emissions.Venezuela’s negotiating team also lamented Tuesday that it thinks the efforts to reduce emissions have been left to the developing countries. which are doing more than industrialized nations and that this threatens a second term to the Kyoto Protocol.

Some groups are making efforts to try and mobilize resources to address climate change.

The African Development Bank said Tuesday it will participate in a new agriculture fund in an attempt to get the sector more closely involved in climate change negotiations. The Climate Smart Agriculture fund, which will also involve the World Bank and the United Nations’ Food and Agriculture Organization, will bring together African agriculture ministers and look to fund low-emission and carbon-capture farming projects.

And the global shipping industry body said it would consider helping to find a Green Climate Fund that the U.N. envisions helping the poorer countries adapt to changing weather patterns and mitigate carbon emissions.

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And the process culminates in ‘apoptosis’ or programmed cell-death – a situation in which living organisms (including corals and humans) deliberately destroy their weakened or infected body cells, effectively a form of ‘cell suicide’ or amputation designed to protect the organism as a whole.”Our results suggest that the control of apoptosis is highly complex in the coral-algae symbiosis and that apoptotic cell death cascades potentially play key roles in tipping the cellular life or death balance during environmental stress prior to the onset of coral bleaching,” explained lead author Dr Tracy Ainsworth.

“It is also clear that this chain reaction responds significantly to subtle, daily changes in the environment and to sea temperatures which were generally thought till now to have little impact on the function of coral and its symbiotic algae,” she said.

Paradoxically, the team’s research identified molecular signals both promoting and discouraging programmed cell-death in the corals.

The findings have been published in the latest issue of Scientific Reports published by Nature.

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Ozone, a molecule of oxygen, forms in the stratosphere, filtering out ultraviolet rays that damage vegetation and can cause skin cancer and cataracts.The shield comes under seasonal attack in both polar regions in the local winter-spring.Part of the source comes from man-made chlorine-based compounds, once widely used in refrigerants and consumer aerosols, that are being phased out under the UN’s Montreal Protocol.

But the loss itself is driven by deep cold, which causes water vapour and molecules of nitric acid to condense into clouds in the lower stratosphere.These clouds in turn become a “bed” where atmospheric chlorine molecules convert into reactive compounds that gobble up ozone.

Ozone loss over the Antarctic is traditionally much bigger than over the Arctic because of the far colder temperatures there.In the Arctic, records have – until now – suggested that the loss, while variable, is far more limited.Satellite measurements conducted in the 2010-2011 Arctic winter-spring found ozone badly depleted at a height of between 15 and 23 kilometres.

The biggest loss – of more than 80 per cent – occurred between 18 and 20km.”For the first time, sufficient loss occurred to reasonably be described as an Arctic ozone hole,” says the study, appearing in the British science journal Nature.The trigger was the polar vortex, a large-scale cyclone that forms every winter in the Arctic stratosphere but which last winter was born in extremely cold conditions, Gloria Manney, of the Jet Propulsion Laboratory in California, told AFP in an email.

“The ozone destruction began in January, then accelerated in late February and March, so that ozone values in the polar vortex region were much lower than usual from early March through late April, after which the polar vortex dissipated.”Especially low total column ozone values (below 250 Dobson Units) were observed for about 27 days in March and early April.”The maximum area with values below 250 Dobson Units was about two million square kilometres, roughly five times the area of Germany or California.”This was similar in size to ozone loss in Antarctica in the mid-1980s.

In April, the vortex shifted over more densely populated parts of Russia, Mongolia and eastern Europe for about two weeks.Measurements on the ground showed “unusually high values” of ultra-violet, although human exposure was not constant as the vortex shifted location daily before eventually fading, said Manney.The study, published by the journal, Nature, challenges conventional thinking about the Arctic’s susceptibility to ozone holes. This thinking is based on only a few decades of satellite observations.

Stratospheric temperatures in the Arctic have been extraordinarily varied in the past decade, the paper notes. Four out of the last 10 years have been among the warmest in the past 32 years, and two are the coldest.

In the stratosphere, ozone is protective. At ground level, where it is produced in a reaction between traffic exhaust and sunlight, it is a dangerous irritant for the airways.

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The installation was carried out by Italian engineers together with the Nepalese Ev-K2-CNR team, and was co-ordinated by Giampietro Kohl. At these altitudes, the M12 has to withstand temperatures as low as -30 degree C. Last time I checked, the camera was (a)live and recording stunning images of the 8,848-meter tall peak. The camera uses a wireless connection to transmit images to the Ev-K2-CNR Pyramid laboratory \ observatory located at an altitude of 5,050 meters. Here, the video gets analyzed and forwarded to Italy for further studies. Researchers hope to learn more about climate change and global warming (hyped as much as Apple’s products) using this video and the meteorological data gathered by the world’s highest weather station (8,000 meters) on Everest.

The webcam is only active during daylight hours (0600 to 1800 hours Nepalese time, which corresponds to 0630 to 1830 hours IST), and you can view the live feed by clicking this link.

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Now if you belong to either of the above categories, you might be in trouble, for a survey has revealed that certain aquatic species, particularly freshwater ones, are on the verge of becoming extinct.The International Union for Conservation of Nature (IUCN) ‘Red list’ has warned that few freshwater species of Western Ghats are undergoing collateral damage due to the rapid economic development. The list states that freshwater fish, molluscs, and several aquatic plants have started showing ‘tendencies for extinction.’

According to the IUCN report, freshwater fish are the most threatened group in peninsular India, with more than 37% at risk of global extinction. For example, the endangered Deccan Mahseer is one of the most sought-after edible fish. However, due to over-harvesting, invasive species, and pollution, it has declined massively in the past decade. The same is the case with Miss Kerala (Puntius denisonii), another edible variety of fish.

It’s not just the fish lovers who are in trouble. Certain communities in India rely on freshwater species for their livelihoods. This includes both edible fish and marine plants. Once the species become extinct, it might be hard for them to make their living.

About 28% of aquatic plants have medicinal value and these have started becoming extinct, the report has found. For example, Cremnochonchus syhadrensis, an endangered freshwater periwinkle, and a pond weed Aponogeton satarensis are slowly becoming extinct.

“Water pollution from agricultural and urban sources, over-harvesting and invasive species were the major threats that have led to 16% of freshwater species becoming extinct,” said Sanjay Molur, executive director, Zoo Outreach Organization, in the report. “If we continue to degrade our freshwater systems and over-harvest our resources, we will not only lose biodiversity but also many valuable services that nature provides us for free,” says Rajeev Raghavan, Conservation Research Group at St. Albert’s College, Kochi.

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Their paper also announces the rediscovery of three night frogs thought to be extinct for the last several decades.In a press release on Thursday, the University of Delhi said the rediscovered Coorg Night Frog (Nyctibatrachus sanctipalustris) had not been seen by researchers since it was reported 91 years ago. The Kempholey Night Frog (Nyctibatrachus kempholeyensis) and Forest Night Frog (Nyctibatrachus sylvaticus), the other two rediscoveries, had eluded sighting since they were reported 75 years ago.

The 12 new species were identified following a revision of the night frog genus Nyctibatrachus from specimens collected from the Western Ghats forests spread along the States of Kerala, Tamil Nadu, Karnataka, Goa and Maharashtra during fieldwork over the last 20 years, the press release said.

The researchers have named the new species as Nyctibatrachus acanthodermis, Nyctibatrachus danieli, Nyctibatrachus devein, Nyctibatrachus gavi, Nyctibatrachus grandis, Nyctibatrachus indraneili, Nyctibatrachus jog, Nyctibatrachus periyar, Nyctibatrachus pillaii, Nyctibatrachus poocha, Nyctibatrachus shiradi and Nyctibatrachus vrijeuni. (The name Nyctibatrachus is composed of two words — ‘nycti’ derived from the Greek ‘nux’ meaning night and ‘batrachus’ meaning frog).

These new discoveries take the number of new species described by herpetologist Dr. Biju and his colleagues over the last eight years from specimens collected from the Western Ghats during two decades of field work to 45. One of the earlier discoveries of the team led by him, a purple burrowing frog given the name Nasikabatrachus sahyadrensis belonging to an entirely new family of frogs, was celebrated by the scientific world as a “once in a century find”.

Six of the 12 new species are from unprotected, highly degraded habitats. The night frogs require unique habitats — either fast flowing streams or moist forest floor for breeding and survival. They fertilise and reproduce without physical contact. The paper reporting these finds also describes the reproductive strategy and parental care habits of six of the new species.

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