Tuesday, December 29, 2009

Arsenic alarm in Bihar and Jharkhand Villages of India.

Bihar and Jharkhand is facing one of the gravest natural disasters in the form of arsenic contamination of ground water.
Dr. Nitish Priyadarshi

Thousands of people living in over hundreds of villages in different district of Bihar and Sahebganj district of Jharkhand state in India are facing serious threat to their health due to alarmingly high quantity of arsenic present in the underground water.

Bihar is facing one of the gravest natural disasters in the form of arsenic contamination of ground water. In the first detailed study of ground water quality, the Department of Environment and Water Management, A.N.College, Patna, has already submitted Interim Reports to PHED and UNICEF about the alarming findings on arsenic poisoning cases in the districts of Patna, Bhojpur, Vaishali and Bhagalpur. The study was conducted from April 2004 to May 2006, the study area being confined to 10 kms. wide belt along the Ganga river as per the instructions of PHED and UNICEF.

According to Dr.Ashok Ghosh, Principal Investigator of Project Arsenic, Dept. Of EWM, A.N.College, these findings are just the tip of the iceberg, as more contaminated aquifers are waiting to be detected in the remaining parts of the state. The water quality testing was done initially by Field Test Kits and then confirmed by AAS or UV Spectrophotometric tests. Epidemiological studies indicate that drinking water having more than permissible arsenic levels of 10 ppb. increases the mortality rates as arsenic is a bio-accumulative toxin.

Persons suffering from arsenicosis have not yet responded to known treatment procedures. The high the intake of arsenic, along with under nourishment and lack of medical help have worsened the lives of the population in the arsenic affected rural areas. Arsenic can also contaminate standing food crops if it is present in the soil and soil water. As Bihar Plains are highly fertile and its crops are marketed to many distant places, apart from being locally consumed, it becomes imperative to test the levels of arsenic in the food chain too. What is worrisome is that arsenic contaminated ground water tables have abrupt occurrences both over time and space. This explains why a public hand pump in village Ramnager in Maner tested 30 ppb. in the post monsoon period and more than 60 ppb. in the month of May. Also arsenic manifestation exists at different levels in different areas. In north-west Maner, arsenic contaminated hand pumps have a shallow depth of between 60 to 80 feet in the diara belt.

In Bhojpur, the depth of contaminated aquifers goes down to 150 feet away from new diara land, while in Vaishali, arsenic is found in the shallow and middle aquifers at an average distance of 5 km. away from the river bank. Regular monitoring of drinking water from hand pumps is immediately required as a part of the mitigation strategy. Patna, the first district to be covered, revealed pockets of high arsenic contamination, above the acceptable limit of 10 ppb., in 171 villages in Maner, Danapur, Sampatchak, Barh, Bakhtiarpur, , Fatuha, Khusrupur, Phulwari, Mokama, Pandarak and Patna City.

1060 village hand pumps were arsenic contaminated The highest AAS reading of arsenic level in government hand pump water is 724 ppb. in village Naikatola in Maner, 450 ppb. in Kasimchak village in Danapur, 553 ppb. in Ghiaspur Mahazi and 538 ppb. in Kala Diara, Bakhtiarpur,, and 484 ppb. in Malahi Banda village in Barh. Sampatchak Block has low contamination levels of below 50 ppb. over a larger area in most of the villages. In Bhojpur, the highest AAS test readings are 1861 ppb. and 1064 ppb. in Pandey tola, Barhara Block, a situation far more serious than the one represented by the much-touted village Ojhapatti of Shahpur Block. Out of the 6292 hand pumps tested, 47.70 % were arsenic contaminated hand pumps. In Barhara, 62.84%, in Udwantnagar 59.39%, in Shahpur 40.41%, in Behea 37.17%, in Koilwar, 29.20%, and in Ara 25.88% of Block level hand pumps were arsenic contaminated. In Vaishali, all the Blocks covered within 10 km. along the Ganga banks, has low level arsenic contamination at present.
In Bhagalpur district most affected areas are Kahalgaon, Pirpainti, Sabaur and Sultanganj. A detailed study has been presented on groundwater metal contents of Sahebgunj district in the state of Jharkhand, with special reference to arsenic. Both tubewell and well waters have been studied separately with greater emphasis on tubewell waters. Groundwaters of all the nine blocks of Sahebgunj district have been surveyed for iron, manganese, calcium, magnesium, copper and zinc in addition to arsenic. Groundwaters of three blocks of Sahebgunj, namely, Sahebgunj, Rajmahal and Udhawa have been found to be alarmingly contaminated with arsenic present at or above 10 ppb.
Rivers flowing through the coal fields of Jharkhand have been reported to carry arsenic responsible for arsenic poisoning in downstream areas of West Bengal. The coal fields of Bachara and Piprawar areas of Jharkhand have contaminated the waters of the Damodar and its tributary, the Safi. According to author, arsenic contamination arises mainly due to the dumping of waste from the coal mines along the river bed. Coals of the area mentioned contains sufficient amount of arsenic.
Arsenic upto 608 parts per billion (ppb) was detected against the permissible limit of 10 ppb in some villages of Kahalgaon block in Bhagalpur district in 2005. Work was carried out by Dr. Sunil Chaudhary of TM Bhagalpur University.
A detailed work was carried out by Dr. Ashok Ghosh, Professor-in-charge, department of environment and water management, A.N. College Patna, in the arsenic affected areas of Bihar State. He found that out of 27,061 hand pumps, 7,218 pumps tested had arsenic contaminated water greater than 10 ppb (26.67%). Highest arsenic value recorded was 1861 ppb. Study also revealed that 87% of the Trivalent arsenic was found in the groundwater of Bihar State.
The study by Bihar's Public Health and Engineering Department (PHED) reveals that the average arsenic content in drinking water in the 12 districts is 500 parts per billion (ppb). The state capital, Patna, is among the affected areas.
According to Dr. Ghosh, a total of 16 Bihar districts (57 blocks) are affected by high level of arsenic in the groundwater. Worst-affected districts are Bhojpur, Buxar, Vaishali, Bhagalpur, Samstipur, Khagaria, Katihar, Chapra, Munger and Dharbanga.
A very alarming recent finding by the research group is the detection of high arsenic content (more than 50 ppb) in the water of River Jaminia – flowing parallel to River Ganga in Bhagalpur district of Bihar.This river merges with Ganga and water from this river is being supplied to urban Bhagalpur without any treatment, alarmed Dr. Ghosh.
Alarmed by the severity of arsenic’s impact on human body in these villages, the team also collected samples of hair and nail of affected persons for detail medical examination to ascertain the level of damage, said Principal Investigators Dr. Ashok Kumar Ghosh and Nupur Bose of A.N. College Patna. The findings indicated that a wider area, including the fertile irrigational lands, was under the grip of arsenic.
According to another research report done by Mr. Dipanka Chakraborti in Semria Ojha Patti village in the Middle Ganga Plain, Bihar, where tube wells replaced dug wells about 20 years ago, analyses of the arsenic content of 206 tube wells (95% of the total) showed that 56.8% exceeded arsenic concentrations of 50 micro g/L, with 19.9% greater than 300 micro g/L, the concentration predicting overt arsenical skin lesions.



Mayon Volcano in the Phillipines may errupt.

Tens of thousands of people living within the danger zone of Mayon Volcano in the Philippines were forced to evacuate to emergency shelters in mid-December 2009 as small earthquakes, incandescent lava at the summit and minor ash falls suggested a major eruption was on the way. On the evening of Dec. 14, the local volcano observatory raised the alert level to Level 3, which means "magma is close to the crater and hazardous explosive eruption is imminent."This natural-color image of Mayon was captured on Dec. 15, 2009, by the Advanced Land Imager on NASA's Earth Observing-1 (EO-1) satellite. A small plume of ash and steam is blowing west from the summit. Dark-colored lava or debris flows from previous eruptions streak the flanks of the mountain. A ravine on the southeast slope is occupied by a particularly prominent lava or debris flow.The Phillipine Star said on Dec. 22 that "ashfall blanketed at least three towns in Albay, raising new health fears for thousands already bracing for an eruption that could come at any time ... Health officials warned the tiny particles could cause respiratory problems or skin diseases, and could affect the thousands of people crammed into evacuation centers.Also on Dec. 22, CNN reported that "tens of thousands of people have already fled their homes. More than 9,000 families -- a total of 44,394 people -- are being housed in evacuation camps after authorities raised the alert status of the country's most active volcano" as "fountains of red-hot lava shot up from the intensifying Mayon volcano."
Image Credit: NASA/Jesse Allen

Wednesday, December 23, 2009

More population more global warming.

Population Explosion may trigger Global Warming.
Dr. Nitish Priyadarshi
Image credit: http://webecoist.com/wp-content/uploads/2008/11/population-explosion1.jpg
The earth’s population has nearly doubled since World War II. More babies than ever than ever have been born, but this is only part of the reason for the increase. More and better food and medical care have kept alive many people who would otherwise have died. This enormous increase in the number of people is called ‘population explosion.’ Many experts believe it is the greatest danger facing mankind. A doubled population means a greater drain on the world’s limited resources.

Increasing in population size, age and distribution is affecting climate by producing more green house gases, either in the form of automobile or in the form of thermal energy to meet increasing electricity demand. A larger global population means a larger demand for everything--most urgently, energy. The world population is growing by 75 million people each year. That’s almost the size of Germany. Today we are nearly 7 billion people. At this rate we will reach 9 billion people by 2040. According to other report, if current fertility rates continued, in 2050 the total world population would be 11 billion, with 169 million people added each year. Almost all growth will take place in the less developed regions, where today’s 5.3 billion population of underdeveloped countries is expected to increase to 7.8 billion in 2050.

More people means more food, and more methods of transportation. That means more carbon and methane because there will be more burning of fossil fuels. If we take the case of Jharkhand state of India, to meet the demand of electricity more and more coal mines are being opened which has thrust more carbon dioxide and methane to the atmosphere.

Life on Earth is dependent on carbon dioxide (CO2) to regulate the temperature of our planet, but too much can create a heat-trapping blanket over our atmosphere. In the last century, unsustainable population growth and excessive consumption have raised levels of CO2 so dramatically that the earth's climate has been altered in ways never experienced before. Agricultural expansion and forest depletion have multiplied emissions of greenhouse gases like CO2, but it is our dependence on fossil fuels that propels monumental atmospheric change. When we burn fossil fuels such as coal, oil, and gas, we release unsustainable levels of CO2—the primary global warming culprit. Those of us living in the developed world bear a majority of the responsibility for reversing this disturbing trend.

The relationships among humans, their activities and global temperature can be assessed by making the appropriate measurements and analyzing the data in a way that shows the connections and their magnitudes. Human population can be closely estimated and the consequences of their activities can be measured. For example, the volume of carbon dioxide, methane and nitrous oxide emissions is an indicator of human's energy and resource consumption.

Population does appear to be a vital factor in the increase in carbon dioxide emissions. According to an estimate, over a third of the doubling of fossil fuel emissions in developed countries between 1960 and 1988 was due to increased population. The significance of this change is its potential for raising the temperature of the earth through the process known as the Greenhouse Effect. Carbon dioxide in the atmosphere prevents the escape of outgoing long wave radiation from the earth to outer space. As more heat is produced and less escapes, the temperature of the earth increases.

The threat of climate change and global warming has therefore, been heavily influenced by population growth. As developing countries, with rapidly increasing populations follow the Western path of development, it is likely to add greatly to the problem. A country like China, for example, which has rapid industrialization and has the largest population in the world is projected to increase its population further, and is expected to become the leading source of global- warming gas emission by 2050.

Increasing population is decreasing forest cover, which happens to be major absorbent of carbon dioxide. Experts agree that population pressure contributes directly to the continuing loss of forest cover. Based on UN Food and Agriculture Organization (FAO) land use estimates, it would appear that in the past three decades or so 59% of the forests cleared in developing countries were for human settlements, roads and other non-agricultural developments- almost entirely related to population growth.

The act of cutting trees to generate farmland, has a great impact on global warming. The cutting of trees is mainly done for paper production, livestock farming etc. Deforestation is responsible for about 20% emission of global warming. Experts opine that deforestation has greater impact on global warming than emissions from factories and automobiles.

Each day the average person breathes in about 15,000 liters, or approximately 35 pounds, of air. (http://www2.envmed.rochester.edu/envmed/TOX/faculty/frampton.html) Since air is 21% oxygen (molecular weight 16) and 78% nitrogen (molecular weight 14) by volume, oxygen is 23.5% by weight and nitrogen is 76.5% by weight in air. So the amount of oxygen breathed in per day by the average person is about 35*0.235 = 8.2 lbs.

Humans breath out about 16% oxygen by volume, so about 5% of the air by volume is converted to CO2, which is about (5/21)x8.2 = about 2 lbs of CO2 every day.

The molecular weight of O2 is 32 and the molecular weight of CO2 is 12+32=44. Therefore, humans emit 44x2x/32 lbs = about 2.8 lbs of CO2 breathed out every day or about 1005 lbs = about 0.5 tons per person per year.

In 2005 the Earth population was about 6.66x109. So the emitted CO2 per year by their breathing was about 3.3x109 tons.
In 2002 CO2 emissions due to human activities were about 25x109 tonnes = 27.6x109 tons (http://www.unep.org/geo/yearbook/yb2006/077.asp). Breathing comprises about 3.3x109 tons of that amount, or about 12% of it.

Globally, annual average emissions of carbon dioxide per capita due to human activities (other than breathing) have been fairly stable since 1990. For 2002, this figure was up to 3.93 tonnes from 3.85 tonnes in 2001 (http://www.unep.org/geo/yearbook/yb2006/077.asp).

Scientists have predicted that the day is not far when nations would fight for drinking water and people would perish due to floods and climate changes. Population explosion, though undeniably the root cause of global warming, has so far been largely overlooked.

UN estimates forecast around 8 to 10 billion population on the planet by 2050 — a galloping 50 per cent increase from the present world population, which is estimated to be 6.5 billion. Scientists have proved that human activities do influence climatic conditions. Therefore, any long-term planning to combat the threat of climate change would not succeed without first finding solutions to rectify the demographic trends.

While industrial nations have been primarily responsible for high emissions levels in the recent past, the rapidly growing population of the developing world will be a major factor in future emissions levels. As we look to the developed world to curb and reduce emissions, many in developing countries need to increase their energy use to meet basic needs and improve their quality of life. Countries such as India and Brazil are looking for solutions to balance the needs of people and the planet. Therefore, all national policies and international agreements on global warming must take population growth into account.

Wednesday, December 16, 2009

High levels of black carbon likely to impact Tibetan Plateau's temperature.

The Dark Side of Black Carbon
Dr. Nitish Priyadarshi
Image Credit: NASA

As interest in Earth's changing climate heats up, a tiny dark particle is stepping into the limelight: black carbon. Commonly known as soot, black carbon enters the air when fossil fuels and biofuels, such as coal, wood, and diesel are burned. Black carbon is found worldwide, but its presence and impact are particularly strong in Asia. Black carbon, a short-lived particle, is in perpetual motion across the globe. The Tibetan Plateau's high levels of black carbon likely impact the region's temperature, clouds and monsoon season.

Black soot deposited on Tibetan glaciers has contributed significantly to the retreat of the world's largest non-polar ice masses, according to new research by scientists from NASA and the Chinese Academy of Sciences. Soot absorbs incoming solar radiation and can speed glacial melting when deposited on snow in sufficient quantities.
Temperatures on the Tibetan Plateau -- sometimes called Earth's "third pole" -- have warmed by 0.3°C (0.5°F) per decade over the past 30 years, about twice the rate of observed global temperature increases. New field research and ongoing quantitative modeling suggests that soot's warming influence on Tibetan glaciers could rival that of greenhouse gases.

Since melt water from Tibetan glaciers replenishes many of Asia's major rivers -- including the Indus, Ganges, Yellow, and Brahmaputra -- such losses could have a profound impact on the billion people who rely on the rivers for fresh water. Areas going to most affected in India would be Uttrakhand, Uttar Pradesh, Bihar, Jharkhand, West Bengal and Assam. While rain and snow would still help replenish Asian rivers in the absence of glaciers, the change could hamper efforts to manage seasonal water resources by altering when fresh water supplies are available in areas already prone to water shortages.
Researchers led by Baiqing Xu of the Chinese Academy drilled and analyzed five ice cores from various locations across the Tibetan Plateau, looking for black carbon (a key component of soot) as well as organic carbon. The cores support the hypothesis that black soot amounts in the Himalayan glaciers correlate with black carbon emissions in Europe and South Asia.
Black carbon or BC is formed through the incomplete combustion of fossil fuel, biofuel, and biomass, and is emitted in both anthropogenic and naturally occurring soot. Black carbon warms the planet by absorbing heat in the atmosphere and by reducing albedo, the ability to reflect sunlight, when deposited on snow and ice. Black carbon stays in the atmosphere for only several days to weeks, whereas CO2 has an atmospheric lifetime of more than 100 years. The term black carbon is also used in soil sciences and geology, referring either to deposited atmospheric BC or to directly incorporated BC from vegetation fires. Especially for the tropics, BC in soils significantly contributes to fertility as it is able to adsorb important plant nutrients .

Black carbon is a potent climate forcing agent, estimated to be the second largest contributor to global warming after carbon dioxide (CO2). Because black carbon remains in the atmosphere only for a few weeks, reducing black carbon emissions may be the fastest means of slowing climate change in the near-term.

Black carbon emissions from northern Eurasia, North America, and Asia have the greatest absolute impact on Arctic warming.

In some regions, such as the Himalayas, the impact of black carbon on melting snowpack and glaciers may be equal to that of CO2.Warmer air resulting from the presence of black carbon in South and East Asia over the Himalayas contributes to a warming of approximately 0.6°C. An “analysis of temperature trends on the Tibetan side of the Himalayas reveals warming in excess of 1°C.

Black carbon sources vary by region. For example, the majority of soot emissions in South Asia are due to biofuel cooking, whereas in East Asia, coal combustion for residential and industrial uses plays a larger role.

Black carbon can be controlled in developing countries through the implementation of cleaner fuels, new cooking technologies, and changing crop management practices.



Monday, December 14, 2009

क्या है समुद्र के नीचे लेमुरिया महाद्वीप का रहस्य?

क्या है समुद्र के नीचे लेमुरिया महाद्वीप का रहस्य ? क्या बदलते तापमान ने इन्हे डुबाया ?
झारखण्ड की मुंडा जाती भी शायद इसी महाद्वीप से होते हुए भारत पहुँची।
डा। नितीश प्रियदर्शी

आज सारे विश्व के वैज्ञानिक इस बात पर सहमत हैं की आने वाले समय में पृथ्वी पर कई विनाशकारी बदलाव होंगे। कारन है ग्लोबल वार्मिंग । कई छोटे द्वीप समुद्र में समां जायंगे । कहीं सूखे की मार होगी तो कहीं अतिवृष्टि । कई नए जगह भूकंप प्रभावित होंगे जो पहले नही थे । यानि विनाश का एक नया रूप सामने आएगा।

कुछ खोजकर्ता इस बात का दावा कर रहें हैं की माया सभ्यता के कैलेंडर मे इस बात का जिक्र है की सन २०१२, २१ दिसम्बर को पृथ्वी का विनाश हो जाएगा।ऐसी बात नही हे की आने वाले समय में ही विनाश होगा । विनाश अगर होगा भी तो अचानक नही । विनाश की प्रक्रिया धीरे धीरे होती है जैसे पहले हुई थी । जब से पृथ्वी बनी है विनाश के कई चरण हुए है जब कई प्रजातियाँ विलुप्त हुई तथा नई आई हैं। विश्व के सभी जातिओं एवं धर्मो में प्राचीन महाप्रलय का उल्लेख मिलता है । केवल धर्मं ही नही भूवैज्ञानिक साक्ष्य भी पृथ्वी पर कई प्राचीन विनाशकारी हलचल को दर्शाता है। चाहे वो भूकंप के रूप मे हो या ज्वालामुखी के रूप मे या ग्लोबल वार्मिंग या हिमयुग के रूप मे हो। विश्व के सभी धर्मो में जल को ही महाप्रलय का कारण माना गया है। यहाँ तक की सभी आदिम जन जातिओं मे भी जल महाप्रलय का उल्लेख कहानिओं के रूप में हुआ है।इसी क्रम में दो महाद्वीपों का नाम उभर कर आता है जो आज महासागर के नीचे है। इनका नाम है "लेमुरिया एवं मु”। वेसे इन द्वीपों का अभी तक वेज्ञानिक पुष्टि नही हो पाई है। लेकिन विश्व के खोजकर्ताओं का दावा है की यह दोनों महाद्वीप पर सभ्यता काफी विकसित थी। कुछ खोजकर्ताओं, जिनमे प्रमुख थे फिलिप स्कोल्टर , का यह भी कहना था की मनुष्य की उत्पत्ति इन्ही महाद्वीपों पर हुई थी। ये दोनों महाद्वीप किसी भूवैज्ञानिक हलचल के वजह से समुद्र के भीतर समां गए।

एक रोचक तथ्य यह सामने उभर कर सामने आया है की हमलोग की आगे की पीढ़ी शायद फिर लेमुरिया द्वीप पर वास करे। खोजकर्ताओं का मानना है की जिस तरीके से लेमुरिया द्वीप समुद्र के अन्दर समां गया शायद भविष्य मैं किसी प्लेट टेक्टोनिक या किसी भूगर्भीय हलचल की वजह से यह द्वीप समुद्र के ऊपर आ जाए। एक और रोचक तथ्य सामने यह आया है की लेमुरिया द्वीप के लोग काफ़ी लंबे होते थे। उनके पास तीसरा आँख भी था जो सर के पीछे होता था। यही आँख आज के मनुष्य मैं pineal eye के नाम से जाना जाता है। इसका अब कोई कम नही है। लेकिन इसपर अभी कोई खोज नही हुआ है।एसा माना जाता है की लेमुरिया महाद्वीप हिंद महासागर के नीचे एवं मु महाद्वीप प्रशांत महासागर के नीचे समा गया। खोजकर्ताओं की माने तो "मु" महाद्वीप ५०,००० वर्ष पहले तक था एवं "लेमुरिया द्वीप" की उत्पत्ति एक लाख साल पहले हुई थी।ऐसा लगता है जिस वक्त ये दोनों महाद्वीप समुद्र के नीचे समाये उस वक्त पृथ्वी का तापमान आज के तुलना में ज्यादा रहा होगा जिसके चलते हिमनदों के पिघलने से समुद्र का जलस्तर ऊँचा उठा एवं इन दोनों महाद्वीपों को धीरे धीरे अपने भीतर समां लिया। वेसे भी आज के बढ़ते तापमान की वजह से विश्व के कई छोटे छोटे द्वीप खतरें मैं आ गए है।
पहले भी हमारे पृथ्वी पर कई बदलाव हुए आज जहाँ पर सुखी जमीन है वहां पहले समुद्र हुआ करता था। आज जहाँ रेगिस्तान है वहां पहले हरियाली हुआ करती थी। पृथ्वी पर प्राचीन काल के जिओलोजिकल विनाश के अवशेष आज भी मिलते है । एल्फ्रेड रसेल एवं एर्नेस्ट हेकेल का मानना था की मनुष्य की उत्पत्ति इन महाद्वीपों पर हुई थी। लेमुरिया शब्द लेमूर नामक जीव से आया जो बन्दर एवं गिलहरी का मिश्रित रूप है। लेमूर का मूल स्थान मेडागास्कर है लेकिन यह भारत एवं मलाया मे भी पाया जाता है। इसलिये यह माना गया की ये जीव तभी भारत पहुंचें होंगे जब कोई विशाल महाद्वीप हिंद महासागर में रहा होगा एवं जो भारत एवं मेडागास्कर के बिच में सेतु का काम किया।

वैज्ञानिक मानते हैं की भारत उप महाद्वीप में किसी नर-वानर की उत्पत्ति नही हुई थी। अतः जितनी भी जातियां भारत की धरती पर जीवित हैं या लुप्त हो चुकीं हैंउनका मूल स्थान कहीं न कहीं भारत से बाहर रहा था। झारखण्ड के मुंडाओं के मूल स्थान तथा उनके आव्रजन मार्ग की खोग में लेमुरिया सिद्धांत का उल्लेख हुआ है।एस सी रॉय ने इस सिद्धांत का प्रतिपादन किया है। श्री रॉय ने दक्षिण अफ्रीका एवं दक्षिण भारत के बिच एक लेमुरिया द्वीप की कल्पना की है जो अब जलमग्न हो चुका है। उन्होंने संभावना व्यक्त की है की मुंडा जाती लेमुरिया द्वीप से होती हुए भारत आई थी। इस प्रसंग में दक्षिण अफ्रीका के मेडागास्कर का नाम उल्लेखित हुआ है। इस मत के अनुसार मुंडाओं का मूल स्थान मेडागास्कर है और भारत आव्रजन "लेमुरिया द्वीप" से होते हुए हुआ है।अब सवाल यह उठता है की अगर यह दोनों महाद्वीप थे तो ये समुद्र में कैसे समा गए। क्या समुद्र के बढ़ते जलस्तर ने इनको अपने अन्दर समा लिया या किसी भुवेज्ञानिक हलचल के चलते यह महासागर के अन्दर चले गए । अभी भी इसपर खोज जारी है।सवाल लेमुरिया या मु का नहीं है । सवाल यह है की अगर पृथ्वी का तापमान यूँ ही बढ़ता रहा तो आने वाले समय में कोई दूसरा लेमुरिया या मु जैसी घटना होने से इंकार नही किया जा सकता।

Saturday, December 12, 2009

Varves are the best indicators of ancient climate change.

Varves has the similarity with the regular, annual rings of the trees.
Dr. Nitish Priyadarshi

The study of climates during the geological past, is one of the most topical areas of research in the geosciences at present. The threat of future climate change caused by higher levels of green house gases, which would drastically alter many aspects of our environment, has prompted much research to try to understand how our own complex climate system works. Only by understanding how climate has evolved over million of years can we identify important climate cycles with a frequency in excess of the short climate records we possess. These climate cycles have the potential to have a profound effect on our environment.

Understanding our climate history in the geological past is also important for climatologists trying to construct accurate numerical computer models of our present climate system to use for predicting future climate change. It is obviously not possible to check the accuracy of models that are predicting the future so climatologists must turn to the past to see if their models can accurately simulate ancient climates. It is therefore the role of the geoscientists to collect as many data as possible from the rock record.

There are many rocks/minerals whose formations are controlled by climate, such as bauxite, coal and varves.
This article aims to introduce the formation of varves and how they can be used to determine ancient climate conditions.
What is Varve?

A varve is any sedimentary bed or lamination deposit within the period of one year, or any pair of contrasting laminae representing seasonal sedimentation (as summer and winter) within the period of one year.

In its broadest sense the term is applied to the layer of sediment deposited in a single year. In practice, however, the use of the term is almost always confined to sediments deposited in glacial melt-water lakes. These consist of coarser layer, representing summer deposition, and a finer layer, representing winter deposition. Counting and correlation of these varves has led to the development of a detailed Pleistocene chronology for the Northern Hemisphere.

Varves form distinctive layers. A varve consists of two layers; a thick light colored layer of silt and fine sand which forms in the spring and summer and a thin dark colored layer of clay forming in the fall and winter. Since low temperatures are necessary in delaying the settling of clay particles, it is assumed that varve formation can occur only in glacial waters, particularly lakes on the margins of glaciers. The salt and electrolytes in seawater cause a homogenous mass, preventing the formation of varves.
The deposition of varved sediments is either caused by seasonal variations in the glacial melt-water discharge (glacial varves) or by seasonal variations in the river discharge (postglacial varves).

The study of varved clays goes back to about 1880, when De Geer, working in the Stockholm area in Sweden, “was struck by the marked cyclical banding of the varved clay. From the obvious similarity with the regular, annual rings of the trees. Geer got at once the impression that both ought to be annual deposits”.
According to Sauramo (1923), there are four characteristics of varve: the grain size, the colour, the plasticity, and the chemical composition. The dominating rhythemic arrangement of a varve is alteration between coarse and lighter summer units and finer and darker winter units. These granulometrically graded varves are termed diatactic varves. There are also non graded varves, with the seasonal rhythm expressed only in the colour ranges (darker winter units). These varves are known as symmict varves and are common in brackish water environment.
Of the many rhythmites found in the geological record, varves are one of the most important and illuminating to studies of past climate change. Varves are amongst the smallest-scale events recognised in stratigraphy. Varves form only in fresh or brackish water, because the high levels of salt in normal sea water coagulates the clay into coarse grains.

Varve analysis is the process of counting varves or annually laminated sediments to determine the rates of change in climate and various ecosystems. Varves form when glacial advances come in contact with bodies of water such as lakes. When this process occurs, layers of sediment form on the floor of the body of water. This technique provides an opportunity to acquire detailed chronological information about the composition, displacement, and climate of that region, at that time.
Doyle, P. and Bennett, M. R. 1999. Unlocking the Stratigraphical Record, advances in Modern Stratigraphy. John Wiley & Sons, New York.

Fairbridge, R. W. and Bourgeois, J. 1978. The Encyclopedia of Sedimentology. Dowden, Hutchinson Ross, Inc. Pennsylvania.

Sauramo, M., 1923. Studies of the Quaternary varve sediments in southern Finland, bull. Comm.. Geol. Finlande, 60, 164p.


Tuesday, December 8, 2009

Tree rings and Pollen helps in measuring global temperature.

For a scientist studying climate change, “eureka” moments are unusually rare.

Dr. Nitish Priyadarshi
photo credit:http:// boojum.as.arizona.edu

In 1938, British meteorologist Guy Stewart Callendar made the first proper measurement of global temperature. He gathered data from weather stations worldwide and found that the average temperature of the earth has increased between 1880 and 1930. Sadly, no one took his findings seriously. In 1957, two scientists set up instruments on the Mauna Kea Volcano in Hawaii to measure the level of carbon dioxide in the atmosphere. Its records show that the level of carbon dioxide has been increasing steadily since that time and that the earth is slowly warming up.

For a scientist studying climate change, “eureka” moments are unusually rare. Instead progress is generally made by a painstaking piecing together of evidence from every new temperature measurement, satellite sounding or climate-model experiment. Data get checked and rechecked, ideas tested over and over again.

Evidence for climatic change is taken from a variety of sources that can be used to reconstruct past climates. Reasonably complete global records of surface temperature are available beginning from the mid-late 1800s. For earlier periods, most of the evidence is indirect—climatic changes are inferred from changes in indicators that reflect climate, such as vegetation, pollen, ice cores, dendrochronology, sea level change, and glacial geology.

Pollen in fossils provides important clues to prehistoric global climates. Pollen falls from trees and plants into the soil and can be preserved for thousands of years. Each plant species produces a unique pollen type. By identifying the type of pollen found in a place, scientists can tell which trees grew there. In tropical regions like Indonesia, scientists have found pollen from plants, such as pine, that can grow in temperate climates. This means that the temperature in the world’s tropical areas may have been lower in the past, allowing temperate plants to grow there. Pollen is widely distributed, produced in vast quantities (one pine branch can produce 350 million pollen grains), easily recognisable and very resistant to decay (some pollen in East Africa goes back 3 million years). The fluctuating type and distribution of pollen assists in interpreting local and regional histories of vegetation and climate.

Scientists also study tree rings to learn about the earth climate in the past. Tree rings are a good place to start thinking about how climate researchers get information about past climates. In certain cases, trees can live for many hundreds of years and in an extraordinary case, like the bristlecone pine, thousands of years! Each year trees add growth rings, which can indicate what sort of growing season the tree experienced. Interestingly these rings are more than a temperature indicator, they also tell the researcher about moisture and cloudiness as well. Trees grow faster in warmer climates than in cooler environments. Each year, the trunk of a tree grows wider. If you can chop a tree down, you will see rings in the cross-section of the trunk. A tree produces a new ring each year. Scientists measure the width of individual rings to estimate climate conditions at the time each ring was formed. Tree rings grow during warmer years are thicker than those produced in colder years. In other words wide and thick rings indicate a fertile, well-watered growing period, whilst thin, narrow rings indicate a time of lower rainfall and less-than-ideal growing conditions.

In this way, scientists can calculate which were the warmer and colder years.

Tree-ring measurements can help to distinguish anthropogenic from natural environmental change. These data can be used to determine whether recent climatic changes are unusual and possibly due to anthropogenic effects (specifically, increasing CO2 and other trace gases) or are still within the range of natural climate variability.

Saturday, December 5, 2009

Some scientists disagree with Global Warming Theory.

They say it is natural.


Dr. Nitish Priyadarshi

Rising temperature are already the clearest sign of climate change. So far, according to the IPCC, global average temperatures have risen 0.60 C above the pre-industrial average. Nine of the hottest years on record have occurred since 1988; six of the first eight months of 1998 were the warmest since records began in 1866; and July 1998 was the hottest month ever.

Scientists who assess the planet’s health see indisputable evidence that earth has been getting warmer, in some cases rapidly. Most believe that human activity, in particular the burning of fossil fuels and the resulting buildup of green house gases in the atmosphere, have influenced this warming trend. In the past decades scientists have documented record-high average annual surface temperatures and have been observing other signs of change all over the planet: in the distribution of ice, and in the salinity, levels, and temperatures of the oceans.

Everywhere on earth ice is changing. The famed snows of Kilimanjaro have melted more than 80 percent since 1912. Glaciers in the Garhwal Himalayas in India are retreating so fast that researchers believe that most central and eastern Himalayan could virtually disappear by 2035. Artic sea ice has thinned significantly over the fast half century, and its extent has declined by about 10 percent in the past 30 years.

This is one of the aspect of the global warming which most of scientists believe is man made. There is small minority of atmospheric and other scientists who disagree with this general scientific consensus. According to these scientists we still know too little about natural climate variables that could change the assessment (up or down). In addition, computer models used to predict climate change are improving but still are not reliable.

They also point out that some signs of global warming may not necessarily be caused by human activities. For example, while many glaciers are shrinking, others are growing. Also, glaciers shrink and grow naturally over long periods of time for reasons that are largely unknown.

Finally, they contend that global warming may be a lot less damaging than many people think and can be beneficial for some regions. For example, some countries may be able to increase crop productivity because of more rainfall and longer growing seasons.

They also claim that more carbon dioxide in the atmosphere could increase the rate of photosynthesis in areas with adequate amounts of water and other soil nutrients. This would remove more carbon dioxide from the atmosphere and help slow atmospheric warming.

However recent studies cast doubt on such a generalization for two reasons. First, this effect would slow as the plants reach maturity and take up less carbon dioxide. Second, it is a temporary effect. When the plants die and are decomposed or burned, the carbon they stored is returned to the atmosphere as carbon dioxide.

Are we heading towards major disaster or it is a simply a natural shifting of climate as it happened in the geological past. During the last 2 billion years the Earth's climate has alternated between a "Ice House", like today's world, and a steaming "Hot House", like the world of the dinosaurs. Jurassic climate stayed warm and became more humid. The polar areas were ice-free during this Period.

The history of earth’s climate is characterized by change. Times of glaciations on the earth have been followed by warm intervals and the duration in years of both cold and warm intervals has varied by several orders of magnitude.

What ever may be the truth we have no options but we have to opt wait and watch theory if we don’t stop carbon emission recklessly. But it is also true that the climate of the earth is changing from the time of its birth from hot to cold and cold to hot. Earlier too the earth has passed through global warming due to natural causes, but this time we the humans are culprits for the changes. When man-made factors are added to the natural ones, the ecosystem may be damaged beyond repair.

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.
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.


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.


Tuesday, November 24, 2009

Is 2012 the end of the world?

Are we heading towards Lemuria or Mu type disaster?
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.
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.

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.