The Earth receives energy from the Sun in the form of radiation. Most of the energy is in visible wavelengths and in infrared wavelengths that are near the visible range (often called "near infrared"). The Earth reflects about 30% of the incoming solar radiation. The remaining 70% is absorbed, warming the land, atmosphere and ocean.
For the Earth's temperature to be in steady state so that the Earth does not rapidly heat or cool, this absorbed solar radiation must be very closely balanced by energy radiated back to space in the infrared wavelengths. Since the intensity of infrared radiation increases with increasing temperature, one can think of the Earth's temperature as being determined by the infrared flux needed to balance the absorbed solar flux. The visible solar radiation mostly heats the surface, not the atmosphere, whereas most of the infrared radiation escaping to space is emitted from the upper atmosphere, not the surface. The infrared photons emitted by the surface are mostly absorbed in the atmosphere by greenhouse gases and clouds and do not escape directly to space.
The reason this warms the surface is most easily understood by starting with a simplified model of a purely radiative greenhouse effect that ignores energy transfer in the atmosphere by convection (sensible heat transport, Sensible heat flux) and by the evaporation and condensation of water vapor (latent heat transport, Latent heat flux). In this purely radiative case, one can think of the atmosphere as emitting infrared radiation both upwards and downwards. The upward infrared flux emitted by the surface must balance not only the absorbed solar flux but also this downward infrared flux emitted by the atmosphere. The surface temperature will rise until it generates thermal radiation equivalent to the sum of the incoming solar and infrared radiation.
But the temperature of the atmosphere generally decreases with height above the surface, at a rate of roughly 6.5 °C per kilometer on average, until one reaches the stratosphere 10–15 km above the surface. (Most infrared photons escaping to space are emitted by the troposphere, the region bounded by the surface and the stratosphere, so we can ignore the stratosphere in this simple picture.) A very simple model, but one that proves to be remarkably useful, involves the assumption that this temperature profile is simply fixed, by the non-radiative energy fluxes. Given the temperature at the emission level of the infrared flux escaping to space, one then computes the surface temperature by increasing temperature at the rate of 6.5 °C per kilometer, the environmental lapse rate, until one reaches the surface. The more opaque the atmosphere, and the higher the emission level of the escaping infrared radiation, the warmer the surface, since one then needs to follow this lapse rate over a larger distance in the vertical. While less intuitive than the purely radiative greenhouse effect, this less familiar radiative-convective picture is the starting point for most discussions of the greenhouse effect in the climate modeling literature.
Friday, January 23, 2009
Wednesday, January 21, 2009
Global Warming
Global Warming is defined as the increase of the average temperature on Earth. As the Earth is getting hotter, disasters like hurricanes, droughts and floods are getting more frequent.
Over the last 100 years, the average temperature of the air near the Earth´s surface has risen a little less than 1° Celsius (0.74 ± 0.18°C, or 1.3 ± 0.32° Fahrenheit). Does not seem all that much? It is responsible for the conspicuous increase in storms, floods and raging forest fires we have seen in the last ten years, though, say scientists.
Their data show that an increase of one degree Celsius makes the Earth warmer now than it has been for at least a thousand years. Out of the 20 warmest years on record, 19 have occurred since 1980. The three hottest years ever observed have all occurred in the last eight years, even.
But it is not only about how much the Earth is warming, it is also about how fast it is warming. There have always been natural climate changes – Ice Ages and the warm intermediate times between them – but those evolved over periods of 50,000 to 100,000 years.
A temperature rise as fast as the one we have seen over the last 30 years has never happened before, as far as scientists can ascertain. Moreover, normally the Earth should now be in a cool-down-period, according to natural effects like solar cycles and volcano activity, not in a heating-up phase.
It's not that I want people to disappear. I got rid of human beings theoretically to see how nature would respond without having to deal with us constantly heaping more abuse on the planet. Ultimately, the aim is to figure out if there is a way to add humans back into the mix so that we could live in harmony with nature as opposed to mortal combat with it.
The problem with environmental books, as brilliant as they often are, is that they are so depressing and scary that only environmentalists read them. I wanted to write something that would reach a huge audience, but still be realistic. I wasn't going to pull any punches.
The latest report from the Intergovernmental Panel on Climate Change delivered a huge blow to global warming skeptics. Leading climate scientists are now 90 percent sure that human activity is heating up the planet. They present various scenarios that show where global warming could take us by the end of the century. The choice is ours.
In conclusion, global warming is a very serious problem affecting us all. The scientific community is unanimously convinced that it is the result of human activity, in particular, the release of greenhouse gases caused by burning fossil fuels. Global warming cannot be stopped entirely, but its potential damage can be minimized by lessening our dependence on fossil fuels. We need to change our lifestyles in order to protect our children and grandchildren and leave them a world they can be proud of!
Over the last 100 years, the average temperature of the air near the Earth´s surface has risen a little less than 1° Celsius (0.74 ± 0.18°C, or 1.3 ± 0.32° Fahrenheit). Does not seem all that much? It is responsible for the conspicuous increase in storms, floods and raging forest fires we have seen in the last ten years, though, say scientists.
Their data show that an increase of one degree Celsius makes the Earth warmer now than it has been for at least a thousand years. Out of the 20 warmest years on record, 19 have occurred since 1980. The three hottest years ever observed have all occurred in the last eight years, even.
But it is not only about how much the Earth is warming, it is also about how fast it is warming. There have always been natural climate changes – Ice Ages and the warm intermediate times between them – but those evolved over periods of 50,000 to 100,000 years.
A temperature rise as fast as the one we have seen over the last 30 years has never happened before, as far as scientists can ascertain. Moreover, normally the Earth should now be in a cool-down-period, according to natural effects like solar cycles and volcano activity, not in a heating-up phase.
It's not that I want people to disappear. I got rid of human beings theoretically to see how nature would respond without having to deal with us constantly heaping more abuse on the planet. Ultimately, the aim is to figure out if there is a way to add humans back into the mix so that we could live in harmony with nature as opposed to mortal combat with it.
The problem with environmental books, as brilliant as they often are, is that they are so depressing and scary that only environmentalists read them. I wanted to write something that would reach a huge audience, but still be realistic. I wasn't going to pull any punches.
The latest report from the Intergovernmental Panel on Climate Change delivered a huge blow to global warming skeptics. Leading climate scientists are now 90 percent sure that human activity is heating up the planet. They present various scenarios that show where global warming could take us by the end of the century. The choice is ours.
In conclusion, global warming is a very serious problem affecting us all. The scientific community is unanimously convinced that it is the result of human activity, in particular, the release of greenhouse gases caused by burning fossil fuels. Global warming cannot be stopped entirely, but its potential damage can be minimized by lessening our dependence on fossil fuels. We need to change our lifestyles in order to protect our children and grandchildren and leave them a world they can be proud of!
Monday, January 12, 2009
Tuesday, January 6, 2009
Israel Aggression on Palestinian People
Well If you got power then you should know your limit. If someone who dont know his/her limit like Israel then the consequences will be bear by the Palestinian. Who supporting and gave him suchh power evry body know all about. But no one has the right to attack civilian in such a brutal way and kill innocent people.
Why such things happend because Palestinian people are less powerfull, no regular army and dont have modern and latest weopened for self defence. If they have then you think Israel will attack on them, Never......Ever........
But there are some forces and even super power who still supporting Israel aggression on Palestine people. And all world are watching the show of Israeli airforce and Tanks. No one even bother to do something for Palestine people. UN is helpless and democratice forces who wants democracy all over the world and peace are watching the brutality and aggression of Israel.International media and Human rights agencies are not doing much for the Palestine People in the same way.
No one have sympathy with Palestinian? why?
I request to all Muslim Ummah and internatiopnal Communities to do much and demand for early seize fire from Israel. And they have to put pressure on the Israel for immediate seize fire from one side immediately.
I think if we are fail to do so then Palestine civilian faced much Casualities and losses. And it will enhance Muslim people anxiety and anger in lang run..
Why such things happend because Palestinian people are less powerfull, no regular army and dont have modern and latest weopened for self defence. If they have then you think Israel will attack on them, Never......Ever........
But there are some forces and even super power who still supporting Israel aggression on Palestine people. And all world are watching the show of Israeli airforce and Tanks. No one even bother to do something for Palestine people. UN is helpless and democratice forces who wants democracy all over the world and peace are watching the brutality and aggression of Israel.International media and Human rights agencies are not doing much for the Palestine People in the same way.
No one have sympathy with Palestinian? why?
I request to all Muslim Ummah and internatiopnal Communities to do much and demand for early seize fire from Israel. And they have to put pressure on the Israel for immediate seize fire from one side immediately.
I think if we are fail to do so then Palestine civilian faced much Casualities and losses. And it will enhance Muslim people anxiety and anger in lang run..
Wednesday, December 24, 2008
Tension between Pakistan and India
A MONTH since the Mumbai attacks, tension between India and Pakistan is not abating. While the war hysteria drummed up in the media on both sides has subsided, it would be a mistake to write off the possibility of conflict. In fact, with two of the world’s largest armies on both sides of the border, conflict is always a possibility — the key is to minimise that possibility at all times. At the moment a dangerous stalemate seems to be developing: India wants Pakistan to act against militants on the basis of circumstantial and political evidence that has convinced the international court of public opinion; Pakistan is demanding proof that will stand up in a court of law. The Pakistani position has some merit; after all, convictions on the basis of scanty or faulty evidence are often overturned by the superior judiciary on appeal. Moreover, Ajmal Kasab’s confessions while in police custody cannot be used in even Indian courts because of laws that prohibit the use of statements that may have been elicited under coercion.The two countries must find a middle ground however. The Mumbai attacks underlined the need for inter-state cooperation on anti-terrorism measures. The subject is part of the eight baskets of the five-year-old composite dialogue, now put on hold by India. A joint framework for dealing with terrorism cases such as Mumbai can address the legal, technical and political issues that currently inhibit cooperation. India should reconsider its stance on the composite dialogue and both countries must work with more urgency to develop an anti-terrorism framework. For its part, Pakistan must understand that a purely legalistic, technical response to the Mumbai attacks will not wash. Nor will superficial measures against the Jamaatud Dawa and affiliated groups impress the outside world, particularly India and the US. There are two distinct issues here: one, to find and prosecute all those who may have been involved in the Mumbai attacks; two, to uproot the jihadi networks that nurtured the individuals responsible. A firm effort by the Pakistan state to address the latter issue will go some way to reducing the tension on our eastern border, and buy time for India and Pakistan to find a way of bringing those involved in the Mumbai attacks to justice. Failing that, we will remain in dangerous uncharted territory. Memories of past Indian restraint will push its government to do something more this time; national pride may force Pakistan to retaliate. The losers will be the people of both countries.
Tuesday, December 23, 2008
Islamic Period
Islamic Period
The light of Islam penetrated in this part of the world as early as 712 A.D from the west with the Arab General Muhammad bin Qasim and during the 10th century A.D from the north with the Turk Sultan Mahmud of Ghaznah ( better known as Mahmud Ghaznavi).
Islam replaced the early way of life of worshipping idols and introduced new philosophy of faith in one God. With Islam in came a new culture in this land from Arabia and Central Asia. Hence, a new type of architecture, hitherto unknown in this area, was introduced. Tens of thousands of Mosques, Madrasahs, tombs and gardens were created by the Muslim rulers all over the Sub-Continent. The new style of Islamic architecture prevailed and matured in this land for over a thousand years. The direct influence of the Muslim Rulers was not only confined to the architecture; their food added a variety of new dishes in the Sub-Continental cuisine. The national dress of Pakistan,“ Shalwar Qamiz” is also a direct gift of the Muslim Turks.
Since the mother tongue of the Muslim Rulers was Arabic, Turkish and Farsi, it was only natural that the local languages of the Sub-Continent were greatly influenced and new language was introduced. Thus the most important contribution of the Muslim rulers to this land is a new language ‘Urdu’ which became the national language of Pakistan since its independence in 1947.
The light of Islam penetrated in this part of the world as early as 712 A.D from the west with the Arab General Muhammad bin Qasim and during the 10th century A.D from the north with the Turk Sultan Mahmud of Ghaznah ( better known as Mahmud Ghaznavi).
Islam replaced the early way of life of worshipping idols and introduced new philosophy of faith in one God. With Islam in came a new culture in this land from Arabia and Central Asia. Hence, a new type of architecture, hitherto unknown in this area, was introduced. Tens of thousands of Mosques, Madrasahs, tombs and gardens were created by the Muslim rulers all over the Sub-Continent. The new style of Islamic architecture prevailed and matured in this land for over a thousand years. The direct influence of the Muslim Rulers was not only confined to the architecture; their food added a variety of new dishes in the Sub-Continental cuisine. The national dress of Pakistan,“ Shalwar Qamiz” is also a direct gift of the Muslim Turks.
Since the mother tongue of the Muslim Rulers was Arabic, Turkish and Farsi, it was only natural that the local languages of the Sub-Continent were greatly influenced and new language was introduced. Thus the most important contribution of the Muslim rulers to this land is a new language ‘Urdu’ which became the national language of Pakistan since its independence in 1947.
Gandhara Civilization
Gandhara Civilization
Pakistan is the land which attracted Alexander the great from Macedonia in 326 B.C., with whom the influence of Greek culture came to this part of the world. During the 2nd century B.C., it was here that Buddhism was adopted as the state religion which flourished and prevailed here for over 1000 years, starting from 2nd century B.C., until 10th century A.D. During this time Taxila, Swat and Charsaddah (old Pushkalavati) became three important centres for culture, trade and learning. Hundreds of monasteries and stupas were built together with Greek and Kushan towns such as Sirkap and Sirsukh both in Taxila. It was from these centres that a unique art of sculpture originated which is known as Gandhara Art all over the world. Today the Gandhara Sculptures occupy a prominent place in the museums of England, France, Germany, USA, Japan, Korea, China, India and Afghanistan together with many private collections world over, as well as in the museums of Pakistan. Nevertheless, the zenith of this Gandhara Art is one and only "Fasting Buddha" now on display in Lahore Museum , Lahore.
Pakistan is the land which attracted Alexander the great from Macedonia in 326 B.C., with whom the influence of Greek culture came to this part of the world. During the 2nd century B.C., it was here that Buddhism was adopted as the state religion which flourished and prevailed here for over 1000 years, starting from 2nd century B.C., until 10th century A.D. During this time Taxila, Swat and Charsaddah (old Pushkalavati) became three important centres for culture, trade and learning. Hundreds of monasteries and stupas were built together with Greek and Kushan towns such as Sirkap and Sirsukh both in Taxila. It was from these centres that a unique art of sculpture originated which is known as Gandhara Art all over the world. Today the Gandhara Sculptures occupy a prominent place in the museums of England, France, Germany, USA, Japan, Korea, China, India and Afghanistan together with many private collections world over, as well as in the museums of Pakistan. Nevertheless, the zenith of this Gandhara Art is one and only "Fasting Buddha" now on display in Lahore Museum , Lahore.
War: is it good or bad.
The current environment between India And Pakistan creats high tension in the region. Indian leadership shows much agression and threatenining that they have the ability to attack Pakistan. while Pakistan, on the other side Pakistan saying that we have the capabilty to defend ourself at any cost.
War is not the solution of anything. War has long effect on either side. As we are underdeveloping country, we are already facing lot of problems, this could be another desasteriouse for our people.
So both the country should start dialouge and resolved all the issue through dialouge.
War is not the solution of anything. War has long effect on either side. As we are underdeveloping country, we are already facing lot of problems, this could be another desasteriouse for our people.
So both the country should start dialouge and resolved all the issue through dialouge.
Wednesday, December 3, 2008
mehargarh8000bc
Indus Civilization
This land also witnessed the glorious era of Indus civilization about 8000 years B.C when the first village was found at Mehargarh in the Sibi District of Balochistan comparable with the earliest villages of Jericho in Palestine and Jarmo in Iraq. Here, during in 1980’s, the French and Pakistani archaeologists have excavated mud built houses of the Mehargarh people and their agricultural land known for the cultivation of maize and wheat, together with polished stone tools, beads and other ornaments, painted jars and bowls, drinking glasses, dishes and plates.
The archaeologists believe that by 7000 B.C., the Mehargarh people learnt to use the metal for the first time. From the first revolution of agricultural life the man moved to another great revolution in his social, cultural and economic life. He established trade relations with the people of Turkmenistan, Uzbekistan, Iran and the Arab world. He not only specialized in painting different designs of pottery, made varieties of pots and used cotton and wool but also made terracotta figurines and imported precious stones from Afghanistan and Central Asia. This early bronze age Culture spread out in the countryside of Sindh, Balochistan, Punjab and North West Frontier Province of Pakistan.
This early beginning led to the concentration of population into the small towns, such as Kot Diji in Sindh and Rahman Dheri in Dera Ismail Khan district. It is this social and cultural exchange that led to the rise of the famous cities of Moenjodaro and Harappa, with largest concentration of population including artisans, craftsmen, businessmen and rulers.This culminated in the peak of the Indus Civilization which was primarily based on intensively irrigated agricultural land and overseas trade and contact with Iran, Gulf States, Mesopotamia and Egypt. Dames were built for storing river water, land was cultivated by means of bullock-harnessed plough - a system which still prevails in Pakistan, granaries for food storage were built, furnace was used for controlling temperature for making red pottery and various kinds of ornaments, beads of carnelian, agate, and terracotta were pierced through and above all they traded their finished goods with Central Asia and Arab world. It is these trade dividends that enriched the urban populace who developed a new sense of moral honesty, discipline and cleanliness combined with a social stratification in which the priests and the mercantile class dominated the society.
The picture of high civilization can be gathered only by looking at the city of Moenjodaro, the First Planned City in the World, in which the streets are aligned straight, parallel to each other with cross streets cutting at right angles. It is through these wide streets that wheeled carriages, drawn by bulls or asses, moved about, carrying well-adorned persons seated on them appreciating the closely aligned houses made of pucca-bricks, all running straight along the streets. And then through the middle of the streets ran stone dressed drains covered with stone slabs - a practice of keeping the streets clean from polluted water, seen for the first time in the world.
This land also witnessed the glorious era of Indus civilization about 8000 years B.C when the first village was found at Mehargarh in the Sibi District of Balochistan comparable with the earliest villages of Jericho in Palestine and Jarmo in Iraq. Here, during in 1980’s, the French and Pakistani archaeologists have excavated mud built houses of the Mehargarh people and their agricultural land known for the cultivation of maize and wheat, together with polished stone tools, beads and other ornaments, painted jars and bowls, drinking glasses, dishes and plates.
The archaeologists believe that by 7000 B.C., the Mehargarh people learnt to use the metal for the first time. From the first revolution of agricultural life the man moved to another great revolution in his social, cultural and economic life. He established trade relations with the people of Turkmenistan, Uzbekistan, Iran and the Arab world. He not only specialized in painting different designs of pottery, made varieties of pots and used cotton and wool but also made terracotta figurines and imported precious stones from Afghanistan and Central Asia. This early bronze age Culture spread out in the countryside of Sindh, Balochistan, Punjab and North West Frontier Province of Pakistan.
This early beginning led to the concentration of population into the small towns, such as Kot Diji in Sindh and Rahman Dheri in Dera Ismail Khan district. It is this social and cultural exchange that led to the rise of the famous cities of Moenjodaro and Harappa, with largest concentration of population including artisans, craftsmen, businessmen and rulers.This culminated in the peak of the Indus Civilization which was primarily based on intensively irrigated agricultural land and overseas trade and contact with Iran, Gulf States, Mesopotamia and Egypt. Dames were built for storing river water, land was cultivated by means of bullock-harnessed plough - a system which still prevails in Pakistan, granaries for food storage were built, furnace was used for controlling temperature for making red pottery and various kinds of ornaments, beads of carnelian, agate, and terracotta were pierced through and above all they traded their finished goods with Central Asia and Arab world. It is these trade dividends that enriched the urban populace who developed a new sense of moral honesty, discipline and cleanliness combined with a social stratification in which the priests and the mercantile class dominated the society.
The picture of high civilization can be gathered only by looking at the city of Moenjodaro, the First Planned City in the World, in which the streets are aligned straight, parallel to each other with cross streets cutting at right angles. It is through these wide streets that wheeled carriages, drawn by bulls or asses, moved about, carrying well-adorned persons seated on them appreciating the closely aligned houses made of pucca-bricks, all running straight along the streets. And then through the middle of the streets ran stone dressed drains covered with stone slabs - a practice of keeping the streets clean from polluted water, seen for the first time in the world.
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