Sunday, November 29, 2009

Carbon equilibrium under threat: The balance between inflow and outflow of carbon dioxide has been disturbed.

Carbon dioxide is rising by 2 or 3 ppm each year.
by
Dr. Nitish Priyadarshi

Climate change is neither new nor unusual. The earth’s average surface temperature and climate have been changing through out the world’s 4.7 billion-year history. Sometimes it has changed gradually (over hundreds to millions of years) and at other times fairly quickly (over a few decades).

Over the past 900,000 years, the average temperature of the atmosphere near the earth’s surface has undergone prolonged periods of global cooling and global warming. During each cold period, thick glacial ice covered much of the earth’s surface for about 100,000 years. Most of this ice melted during a warmer interglacial period lasting 10,000 – 12,000 years that followed each of these glacial periods.

The most widely noted evidence for global warming originated during the International Geophysical Year in 1957, when an observatory was established on top of Mauna Loa volcano in Hawaii. The objective was to study air chemistry in a remote pristine environment. Surprisingly, the observatory recorded rising carbon dioxide levels every year, with concentrations growing from 315 parts per million (ppm) in 1958 to nearly 370 ppm in 1999. The increase wasn’t steady: every May, during the Northern Hemisphere spring carbon dioxide levels dropped slightly as plant growth on northern continents used up some carbon dioxide. Because a majority of the world’s land and vegetation are in the Northern Hemisphere, northern seasons dominate this signal. Subsequent studies have shown that carbon dioxide is increasing about 0.5 percent per year.

For the earth and its atmosphere to remain at a constant temperature, incoming solar energy must be balanced by an equal amount of outgoing energy.

In addition to incoming sunlight, a natural process called the greenhouse effect warms the earth’s lower troposphere and surface.

The two greenhouse gases with the largest concentrations in the atmosphere are water vapor controlled by the hydrologic cycle and carbon dioxide controlled by the carbon cycle.

Since the beginning of the industrial revolution around 1750, human activities have emitted significant amounts of greenhouse gases into the troposphere. Sharp rise is due to the use of fossil fuels, which release large amounts of the greenhouse gas carbon dioxide and methane into the troposphere.

The two largest contributors to carbon dioxide emissions are the world’s thousands of coal-burning power and industrial plants and more than 700 million gasoline-burning motor vehicles. Burning fossil fuels is contributing about 5 to 5.5 billion metric tons of carbon dioxide per year. Burning forests and other biomass, mining limestone for cement making, and other activities also contribute. Total anthropogenic production of carbon dioxide is estimated to be 6.3 billion metric tons per year. If current trends continue, carbon dioxide concentrations could reach about 500 ppm (approaching twice the pre-industrial level of 280 ppm) by the end of the twenty-first century.

Increasing carbon dioxide is warming our planet. It’s simple, as long as we pour carbon dioxide into the atmosphere faster than nature drains it out, the planet warms. And that extra carbon takes a long time to drain out of the atmosphere.

Here are a few of the many findings from such measurements that support the scientific consensus that the earth’s atmosphere is warming. The concentration of carbon dioxide in the troposphere is higher than it has been in the past 420,000 years. The 20th century was the hottest century in the past 1,000 years.

Since 1861 (when direct atmosphere temperature measurements began), the average global temperature of the troposphere near the earth’s surface has risen 0.6 ± 0.20 C, with most of this increase taking place since 1946. Nine of the ten warmest years since 1861 have occurred since 1990. The hottest year was 1998, followed by in order by 2002 and 2001. There is an apparent correlation between increases in fossil fuel use, atmospheric concentrations of carbon dioxide, and global temperature between 1970 and 2002.

Nature protects us by absorbing carbon dioxide. Plants, oceans, and rocks all drain carbon from the atmosphere, but drains are slow. Plants and soil absorb about a third each year, and ocean surface waters about a quarter. The rest stays airborne for a long time. Average time of carbon dioxide in the troposphere is 50 to 120 years. Due to large scale deforestation worldwide threat of increasing carbon dioxide in atmosphere has increased. The balance between inflow and outflow of carbon dioxide has been disturbed.

Time and again, some people claim that human activities are only a minor source of atmospheric carbon dioxide (CO2) which is swamped by natural sources. Compared to natural sources, our contribution is small indeed. Yet, the seemingly small human-made or `anthropogenic' input is enough to disturb the delicate balance. "Anthropogenic CO2 is a biogeochemical perturbation of truly geologic proportions" and has caused a steep rise of atmospheric CO2.

Ice cores show that during the past 1000 years until about the year 1800, atmospheric CO2 was fairly stable at levels between 270 and 290 ppmv (parts per million by volume). The 1994 value of 358 ppmv is higher than any CO2 level observed over the past 220,000 years. The rise of atmospheric CO2 closely parallels the emissions history from fossil fuels and land use changes. All these signs indicates that carbon dioxide rise is human made and affecting the carbon balance of our earth atmosphere.

If I take the example of Ranchi city, the capital of Jharkhand state of India, which was earlier famous for cool climate even in summer, is now passing through drastic climate change from last ten years. Summer is becoming hotter and winter is becoming less cool. All the seasons are coming earlier. Rainfall pattern has also become erratic. Credit goes to increasing carbon dioxide. Sources are the coal mines fire, thermal power stations, increased motor vehicles and above all large scale of deforestation.

Its going to take hundreds of years to remove most of the carbon dioxide that humans are pouring into the atmosphere and hundreds of thousands of years to remove it all. Stopping the rise of carbon dioxide will thus require huge cuts in emissions from cars, power plants, and factories, until inflow no longer exceeds out flow.

By 2008, the level of carbon dioxide in the atmosphere was 385 parts per million (ppm) and rising by 2 or 3 ppm each year. To stop it at 450 ppm ( which is considered dangerously high) the world would have to cut emissions by around 80 percent by 2050.

Reference:

Cunningham, W.P. and Cunningham, M.A. 2002. Principles of Environmental Science, Inquiry and Applications. Tata McGRAW-Hill Edition, New Delhi.

Miller Jr., G.T. 2004. Environmental science, tenth edition. Thomson Brooks/Cole, Australia.

National Geographic Magazine, December, 2009.

http://www.radix.net/~bobg/faqs/scq.CO2rise.html

Tuesday, November 24, 2009

Is 2012 the end of the world?

Are we heading towards Lemuria or Mu type disaster?
by
Dr. Nitish Priyadarshi
Picture credit: http://www.officialcountdown2012.com

A lot of people are listening and worrying about the world coming to an end in 2012. Hollywood is unleashing a raft of movies about humanity tottering on the edge of extinction.

Is 2012 the end of the world? Humans are particularly good at spreading the bad news the reason why it spreads like wildfire. With regard to the predictions of 2012, we’re into the dessert part. No one has anything to present and we’re still swallowing the end of life like it’s on sale at Wal-Mart.
Solar experts from around the world monitoring the sun have claimed that our sun is in a bit of strife. The energy output of the sun is, like most things in nature, cyclic, and it's supposed to be in the middle of a period of relative stability. However, recent solar storms have been bombarding the Earth with so much radiation energy, it's been knocking out power grids and destroying satellites. This activity is predicted to get worse, and calculations suggest it'll reach its deadly peak sometime in 2012.

The other interesting theory is that scientists in Europe have been building the world's largest particle accelerator. Basically its a 27km tunnel designed to smash atoms together to find out what makes the Universe tick. However, the mega-gadget has caused serious concern, with some scientists suggesting that it's properly even a bad idea to turn it on in the first place. They're predicting all manner of deadly results, including mini black holes. So when this machine is fired up for its first serious experiment in 2012, the world could be crushed into a super-dense blob the size of a basketball.

Is our earth is really going to end in 2012? Lots of queries and questions are coming regarding what will happen in 2012. Will we survive? Or it is just a hoax. To me in nature there is no such off and on switching of disaster. All the past scientific and geological researches show the end of the earth cannot happen in few minutes or days. Even today if any asteroids or meteorites struck the earth, complete extinction may take the time of 100 to 1000 years.

Earth cannot be destroyed completely at one time. It may pass through different changes. Either in the form of climate changes, extinction of some old species or submergence of land in the sea due to sea level rise.

Earlier reports say that some old cities or civilizations submerged beneath the sea like Dwarka in India or the Atlantis civilization.

Dwarka is an important city for Hindu Pilgrimage. It was the fabled capital city of Lord Krishna. This "under sea city of Dwarka" lies in close proximity to near the present Dwarka temple in Saurashtra in India. According to archeologists this under-sea city was the real Dwarka where Lord Krishna lived.
According to ancient concept Dwarka submerged into the sea after Sri Krishna left for the heavenly abode. The search for the lost city of Dwarka began as early as in 1930's. Marine Archaeology Unit (MAU) of the National Institute of Oceanography took part in this search in 1983. The search was carried out in the coastal waters of Dwarka in Gujarat. The well-fortified township of Dwarka that extended more than half a mile from the shore was discovered from 1983 to 1990.

What will happen in 2012 no body knows. It’s only a speculations or imaginations based on some mythological concept and not scientific. Every religion talks about some disaster in the ancient past either in the form of floods or in the form of fire from the sky. But scientifically it is not proved.

What will happen if the earthquake of 8 magnitude or more on Richter scale takes place on the earth? It may bring destruction to the specific area. If it takes place beneath the ocean it may bring destruction to bigger area in the form of tsunami but not the complete earth.

Even if great volcanoes erupts it may have the effect on hundreds kilometer. Earth can only be destroyed completely when all events like major earthquakes, volcanoes, shifting of magnetic poles, impact of asteroids or meteorites takes place at the same time in different parts of the earth. Which I am sure is not going to happen.

OK if we are bound to imagine that in year 2012 something is going to happen then what will be the outcome? We can say that the lands may be submerged in the sea either due to Tsunamis or due to the impact of some big object from the outer space. If we believe on the earlier researches there were two imaginary continents which are now under the sea waves. Researchers claim that they vanished due to some natural disasters.

We have all heard about the imaginary islands of Lemuria and Mu which according to different researchers and thinkers are now under the sea.

Researchers say that these islands were submerged in the ocean due to sudden disaster. If something is really going to happen in 2012 are we heading towards the future similar to that of Lemuria or Mu.

Atlantis is by no means the only submerged continent to attract the attention of archaeologists, scientists and historians. Of the remainder the two most important arte Mu (on the bed of the Pacific ocean) and Lemuria, beneath the Indian Ocean. There is also the lost land of Pan below the north Pacific, which antedated Mu over 20,000 years, while Mu itself existed 50,000 years ago. The origins of Lemuria apparently go back 100,000 years or more. All ( as in the case of Atlantis) are claimed to be the original birth place of man, though this clearly cannot be so.

Atlantis has been described as the greatest of all historical mysteries. Plato, writing about 350 BC, was the first to speak of the great island in the Atlantic ocean which had vanished “in a day and a night”, and been submerged beneath the wave of the Atlantic.

The exact location of Lemuria varies with different researchers and authors. Wherever you believe the location of Lemuria to be, it is linked with the Ring of Fire. Researchers claim that this area has become active with Tsunami in December 26, 2004, powerful earthquakes and volacanoes that continue, after being dormant for many years. It would seem that the legends of ancient Lemuria speak to us once again with warning signs- as they supposedly did to the Lemurians- before the continent-or group of islands-fell into the sea.

Mu is supposedly a continent that sink in the Pacific Ocean, rather than the Atlantic. The British archaeologist James Churchward made this claim in 1926. In his report he described a country with a far superior culture that had disappeared together with its continent in the aftermath of volcanic eruption.

Even if something related to the concept of 2012 is going to happen we are sure that it is going to affect only small part of the earth and not the whole planet.

It is also true that nothing natural will destroy the earth. It is we human who will be responsible for the destruction of our mother planet, either in the form of nuclear explosion, carbon dioxide emission or other green house gases emission.

Sunday, November 15, 2009

An unidentified shadow showed the presence in my house?

You may call it shadow, spirit, or Ghost or even some other unidentified object.
by
Dr. Nitish Priyadarshi
Sketch of the unknown shadow drawn by my daughter.

Dear friends I am sure this information may surprise you as this blog is not the write place for discussion on the topic like this which is not related to environment and geology. Though it is not related to the environment directly but it may be related to the environment of the unknown world. This happened last night in my residence. After finishing the dinner I went upstairs to watch the TV. My daughter who is 14 years old was studying on dining table and my son went to sleep. My wife was napping on the sofa in the drawing room. It was 11:30 in the night when suddenly two cats entered in the dining room from my backyard. To kick them out from the house my daughter ran behind them. After coming outside the house she tried to locate the cats. As it was complete dark outside she switched on the light and suddenly she was shocked as she saw someone standing in front of her wearing black gown. At first instance she thought that it may be thief. But the way the shadow was standing she felt something fishy. Only protection was the iron grill which was locked after the servants went to their rooms after finishing the work. She was not able to see the head of the shadow as part of it was behind small tree of red rose. She tried to shout but she was not able to. Suddenly the shadow vanished and my daughter with whispering sound (as she was not able to shout due to fear) called my wife. She saw only the black gown and the hands.

My wife called me down and told the story. I saw the face of my daughter it was pale yellow due to fear and she was trembling. I first tried to console him by saying that it may be her imagination. For her satisfaction and to make her normal I went out in backyard and stayed there for half hour but there was no sign of any unusual happening. I thought she may have suffered from hallucination.

We went to sleep. But this event didn’t ended. At one o’clock in the night my servants who did not know what happened with my daughter earlier, complained the same thing. Only difference was that my daughter saw the shadow standing and according to servants the shadow was moving in the field from one corner to other.

Today morning I asked my daughter to draw the image of the shadow on paper to see how it looked like. Drawing is posted above.

As it was the first incidence in my house so I am confused what to say or to believe. I have always heard from other people or read about such stories in books. Being a student of science my first instinct says that I should not believe on such stories. But what happened with my daughter and afterwards with my servants it forces me to believe the presence of such things of other world which are not known to us. You may call it soul or spirit or Ghost or some other form of energy.

Friday, November 13, 2009

Impact of global warming and climate change on groundwater.

Groundwater level of many areas of the world are going to affected.

by
Dr. Nitish Priyadarshi
Photo credit: knowledge.allianz.com/.../india_drought_quer.jpg

When astronauts first went into space, they were captivated by a vision of the earth that had never been seen before- an earth predominantly blue in colour. After photographs such as this were published, the earth became known as the ‘blue planet’. The earth looked blue because the oceans cover 71 percent of its surface.

Water is essential for life- all living organisms contain water. In fact most living organisms consist of over 60 percent water.

Through out his brief history on earth, man has depended on three basic natural resources for his survival: air, land and water. Of these three, none has been more abused and neglected by man than water. Yet without water, the land produces nothing; without water, life vanishes from the face of the earth. Civilizations arose and have prospered for millennia where water was abundant. The Nile valley is a prime example. When water disappeared, civilizations withered and died. Mesopotamia is a classic example.

The utter human dependence on water is exemplified by the fact that man can survive for five weeks without food, but he dies after only five days without water. If the water supply of a human being is cut off for just a few days, he will die of dehydration long before the water is completely evaporated from his body. Water vapor is lost with every breath, and we cannot avoid breathing.

In recent years due to increasing contamination of surface water bodies, dependency on groundwater for drinking and domestic purpose has increased many fold. But these water sources are now badly affected with global warming. Groundwater is depleting day by day due to effect of rising temperature and urbanization.

The excess soil moisture that saturates subsurface soil or rock and migrates downward under the influence of gravity. In the literal sense, all water below the ground surface is groundwater; in hydrogeologic terms, however, the top of this saturated zone is called the water table, and the water below the water table is called groundwater.

Groundwater is an important part of the water cycle. It comes from rain, snow, sleet and hail that soak into the ground. The water moves down into the ground because of gravity, passing between particles of soil, sand, gravel, or rock, until it reaches a depth where the ground is filled, or saturated, with water. The area that is filled with water is called the saturation zone and the top of this zone is called the water table. The water table may be very near the ground’s surface or it may be hundreds of meters below.

Although groundwater exists everywhere underground, some parts of the saturated zone contain more water than others. An aquifer is an underground formation of permeable rock or loose material which can produce useful quantities of water when tapped by a well. These aquifers may be small, only a few hectares in area, or very large, underlying thousands of square kilometers of the earth’s surface.

The effects of global warming are vast and cover every sphere of one’s life. Both the nature and the living beings are suffering from the effects of global warming. The water resources have been heavily affected by the global warming phenomenon.

In recent times, several studies around the globe show that climatic change is likely to impact significantly upon freshwater resources availability. In India, demand for water has already increased manifold over the years due to urbanization, agriculture expansion, increasing population, rapid industrialization and economic development. At present, changes in cropping pattern and land-use pattern, over-exploitation of water storage and changes in irrigation and drainage are modifying the hydrological cycle in many climate regions and river basins of India.

There have been observed changes in surface temperature, rainfall, evaporation and extreme events since the beginning of the 20th century. The atmospheric concentration of carbon dioxide has increased from about 280 parts per million by volume (ppmv) to about 369 ppmv and the global temperature of the earth has increased by about 0.6°C.

A warmer climate will accelerate the hydrologic cycle, altering rainfall, magnitude and timing of run-off. Warm air holds more moisture and increase evaporation of surface moisture.

If there is little or no moisture in the soil to evaporate, the incident solar radiation goes into raising the temperature, which could contribute to longer and more severe droughts. Therefore, change in climate will affect the soil moisture and groundwater recharge.

With the increase in temperature unconfined aquifers with water tables near ground surface frequently exhibit fluctuations. It can be ascribed to evaporation and/or transpiration. Both processes cause a discharge of groundwater into the atmosphere.

Groundwater supplies are recharged naturally by rain and snow melt. That means we are only able to abstract as much water as that being recharged, otherwise the groundwater supply will run into a “deficit”. It is therefore possible that we can run out of groundwater, at least until the supply has been recharged again. This recharge process can take months, years or even hundreds of years.

Due to warming and climate change rainfall trend has been badly affected worldwide. This change has adversely affected the groundwater recharge.

Water scarcity is expected to become an even more important problem than it is today. There are several reasons for this.

First, the distribution of precipitation in space and time is very uneven, leading to tremendous temporal variability in water resources worldwide. For example, the Atacama Desert in Chile receives imperceptible annual quantities of rainfall whereas Mawsynram, Assam, India receives over 450 inches annually. If all the freshwater on the planet were divided equally among the global population, there would be 5 000 to 6 000 m3 of water available for everyone, every year.

Second, the rate of evaporation varies a great deal, depending on temperature and relative humidity, which impact the amount of water available to replenish groundwater supplies.

The combination of shorter duration but more intense rainfall (meaning more runoff and less infiltration) combined with increased evapotranspiration (the sum of evaporation and plant transpiration from the earth's land surface to atmosphere.) and increased irrigation is expected to lead to groundwater depletion.

Third, as the temperature is rising demand for water is also rising especially in the countries like India, Africa, Bangladesh, South America etc. This demand has put extra pressure on the groundwater resulting depletion of the groundwater.

In a case study of Jharkhand state of India groundwater recharging is mainly dependent on rainfall. Though Jharkhand receives sufficient amount of rainfall (900 to 1400 mm/year) but from last several years the rainfall pattern is very erratic. From last two years Ranchi city the capital of Jharkhand state received sufficient rainfall but distribution of rainfall was not uniform. It rained heavily just for two to three days in the month of August and September which resulted in heavy runoff and less infiltration affecting groundwater level.

Projections of changes in total annual precipitation indicate that increases are likely in the tropics and at high latitudes, while decreases are likely in the sub-tropics, especially along its polar edge. Thus, latitudinal variation is likely to affect the distribution of water resources. In general, there has been a decrease in precipitation between 10°S and 30°N since the 1980s. With the population of low latitude regions increasing, water resources are likely to become more stressed in many regions, especially as global warming intensifies.

By 2100, water scarcity could impact between 1.1 and 3.2 billion people, says a leaked draft of an Intergovernmental Panel on Climate Change (IPCC) report due to be published in April 2007. The report focuses on the consequences of global warming and options for adapting to them. In February 2007 the panel released a report on the scientific basis of climate change.

The IPCC predicts critical water shortages in China and Australia, as well as parts of Europe and the United States. Africa and poor countries such as Bangladesh would be most affected because they were least able to cope with drought.

It is obvious that the projected climate change resulting in warming, sea level rise and melting of glaciers will adversely affect the water balance in different parts of world and quality of groundwater along the coastal plains. Climate change is likely to affect ground water due to changes in precipitation and evapo-transpiration.


Saturday, November 7, 2009

Can animals predict earthquakes?

Most animals show increased restlessness before an earthquake.
Govindpur in Jharkhand animals were nervous before earthquake.
by
Dr. Nitish Priyadarshi

Picture credit: animalsandearthquakes.com/etho-g5.gif
In order to reduce the risk of an earthquake and reduce and mitigate its effects, it is necessary to predict where and when a future, large earthquake may occur. For example, it would be important to know when such an earthquake will hit, where it will strike, and what the level of its destructiveness may be. Earthquake prediction at the present time is not an exact science, and forecasts of earthquake occurrences have not been very accurate. Presently predictions are given in statistical terms. For example, when a prediction is made that :here is a 90% chance that an earthquake will occur in the next 50 years", it does not mean that this earthquake cannot happen tomorrow or it may not be delayed by 50 years. Thus, present predictions are not within a reasonable time frame that can be of usefulness to planners, policy makers, and those in government that deal with public safety.

Unusual behaviour of animals prior to earthquakes received wide publicity after the Haichang earthquake of February 4, 1975 was successfully predicted in China. The official report was presented by the Chinese delegation at the Inter-governmental meeting convened at UNESCO, Paris in February 1976 which stimulated considerable scientific interest. Prior to this, however, several instances of abnormal animal behaviour were noticed before occurrence of some of the damaging earthquakes in different parts of the world, but they were considered more as historical legend. In Japan, innumerable rats were seen every day in a restaurant in Nagoya city, which suddenly disappeared on the evening prior to the Nobi earthquake of 1891.
Since the beginning of recorded history, observations of unusual animal behavior before earthquakes have been recorded by people from almost all civilizations. The animal behavior reports are often ambiguous and not consistently observed. In folklore, some animals have had more reports of being able to predict earthquakes than others, especially dogs, cats, chickens, horses, and other smaller animals. There have been reports with elephants, as well. Goats, cows, and most larger animals are generally reported as being less able to predict earthquakes.

In 1920, the largest earthquake to hit China with a magnitude of 8.5 occurred in Haiyuan County, Ninghxia Province. According to reports of eyewitnesses, prior to this earthquake, wolves were seen running around in packs, dogs were barking unusually, and sparrows were flying around wildly. It is reported that prior to the 6.8 magnitude earthquake in 1966 in Hsingtai County, Hopei Province, in Northern China, all the dogs at a village near the epicenter had deserted their kennels and thus survived the disaster.

The earliest reference we have to unusual animal behavior prior to a significant earthquake is from Greece in 373 BC.

As early as 1886, a seismologist named Milne had mentioned that dogs escaped from the city of Talcahuano in Chile before an earthquake (1835). Flocks of birds flew inland before the Chilean earthquakes of 1822 and 1835. Monkeys were reported to have become restless a few hours before the Managua earthquake (1972) in Nicaragua. In the Tientsin region of China, chickens refused to enter their dens, tigers became restless, yaks declined to eat and horses and sheep started running restlessly a few hours before the earthquakes of July 18, 1969. Hens and cocks were reported restless about an hour prior to the 1896 Ryukyu earthquake in Japan. In Yugoslavia, birds in zoo started crying before the 1963 earthquake. Deer gathered and cats disappeared from villages in northern Italy two or three hours before a damaging earthquake occurred in 1976. Such observations have also been noticed among animals who live underground, like snakes, insects and worms, and those living in water (fishes).

In Japan, fishes were reported to have disappeared before the Kanto earthquakes of 1923. Just before the 1855 Edo earthquake on November 11, many grass snakes were reported to have come out of the ground near the epicentral area, despite severe cold. Other instances involving fishes have been reported in Japan near north-western coast before the 1896 earthquake and the Tango earthquake of 1927 when abundant fishes were caught near the coast.

An interesting instance of unusual behaviour of dogs (but not of other animals) was reported before the destructive earthquake on November 24, 1976 in Turkey (Toksoz,1979).

Although several destructive earthquakes have occurred in the Himalayan region and elsewhere only one authentic observation of unusual animal behaviour was reported in India. In Govindpur in Jharkhand state of India, on February 19, 1892, animals were noticed to sniff the ground and exhibit nervousness such as dog shows in the presence of an unaccustomed object, while the air had distinctly sulphurous smell an hour before the shock.

During the recent damaging earthquakes in India of Uttarkashi (1991), Latur (1993), Jabalpur (1997), Chamoli (1999) and Bhuj (2001), there were reports of isolated cases of unusual behaviour of pet dogs, but the phenomenon was not observed on a large scale. According to the Chief conservator of forests for the Indian state of Tamil Nadu, a few minutes before the killer tsunami waves generated by an underwater earthquake hit the Indian coastline in December 2004, a herd of 500 blackbucks rushed away from the coastal areas to the safety of a nearby hilltop.

The Group of Earthquakes Research of the Institute of Biophysics, China (1979) carried extensive survey of the animal behaviour before damaging earthquakes occur. Its results are summarized below.
1. Most animals show increased restlessness before an earthquake.
2. The precursor time varies from a few minutes to several days, with increased restlessness at 11 hours which becomes still more marked about 2 to 3 hours before the earthquake. In general, the precursor times of various animals are mostly within 24 hours before the earthquake.
3. These observations have been noticed predominantly in the high intensity or epicentral regions close to active faults.
4. Changes in animal behaviour are observed during earth- quakes of magnitude 5 or more.
5. More intense responses can be noticed with the increase of intensity of earthquakes.

We can easily explain the cause of unusual animal behavior seconds before humans feel an earthquake. Very few humans notice the smaller P wave that travels the fastest from the earthquake source and arrives before the larger S wave. But many animals with more keen senses are able to feel the P wave seconds before the S wave arrives. As for sensing an impending earthquake days or weeks before it occurs, that's a different story.
There is little evidence for animals being able to sense earthquakes before they happen, although it is likely they can sense the initial, weaker P-wave or ultrasonic wave generated by a big underground explosion or the rupture of an earthquake, even if the waves are too small for humans' senses. These waves travel faster than the S-wave and Rayleigh earthquake waves that most strongly shake the ground and causes the most damage. It is speculated that when this happens, animals can detect the incoming earthquake wave, and start behaving agitatedly or nervously.

Others postulate that the animal behavior is simply their response to an increase in low-frequency electromagnetic signals. The University of Colorado has demonstrated that electromagnetic activity can be generated by the fracturing of crystalline rock. Such activity occurs in fault lines before earthquakes. According to one study, electromagnetic sensors yield statistically valid results in predicting earthquakes.

Accounts of similar animal anticipation of earthquakes have surfaced across the centuries since. Catfish moving violently, chickens that stop laying eggs and bees leaving their hive in a panic have been reported. Countless pet owners claimed to have witnessed their cats and dogs acting strangely before the ground shook—barking or whining for no apparent reason, or showing signs of nervousness and restlessness.

But precisely what animals sense, if they feel anything at all, is a mystery. One theory is that wild and domestic creatures feel the Earth vibrate before humans. Other ideas suggest they detect electrical changes in the air or gas released from the Earth.

Geologists, however, dismiss these kinds of reports, saying it's "the psychological focusing effect," where people remember strange behaviors only after an earthquake or other catastrophe has taken place. If nothing had happened, they contend, people would not have remembered the strange behavior.

Reference:

Srivastava, H.N., 1983.Earthquakes. National Book Trust, India.

Toksoz, M.N. 1979. Field investigations of the 24 November 1976 earthquakes in Turkey and its precursors. Int. Symp. Eathq. Pred. (UNESCO, Paris), Abstracts.

http://www.drgeorgepc.com/EarthquakePredictionChina.html
http://earthquake.usgs.gov/learn/topics/animal_eqs.php
http://news.nationalgeographic.com/news/2003/11/1111_031111_earthquakeanimals.html

Friday, November 6, 2009

Successful Flight Through Enceladus Plume.

The Cassini spacecraft has weathered the Monday, Nov. 2, 2009, flyby of Saturn’s moon Enceladus in good health and has been sending images and data of the encounter back to Earth. Cassini had approached Enceladus more closely before, but this passage took the spacecraft on its deepest plunge yet through the heart of the plume shooting out from the south polar region. Scientists are eagerly sifting through the results.

In this unprocessed image, sunlight brightens a crescent curve along the edge of Saturn's moon Enceladus and highlights its misty plume. The image was captured by Cassini's narrow-angle camera as the spacecraft passed about 190,000 kilometers (120,000 miles) over the moon. This image has not been validated or calibrated. A validated/calibrated image will be archived with the NASA Planetary Data System in 2010.

At its closest point on Nov. 2, Cassini flew about 100 kilometers (60 miles) above the surface of Enceladus.

Since the discovery of the plume in 2005, scientists have been captivated by the enigmatic jets. Previous flybys detected water vapor, sodium and organic molecules, but scientists need to know more about the plume’s composition and density to characterize the source, possibly a liquid ocean under the moon’s icy surface. It would also help them determine whether Enceladus has the conditions necessary for life.

Mission managers did extensive studies to make sure the spacecraft could fly safely through the plumes and not use an excessive amount of propellant.