Oxygen Depletion: A New Form of Ocean Habitat Loss

Posted on May 11, 2008 by Rashid Faridi

An international team of physical oceanographers including a researcher from Scripps Institution of Oceanography at UC San Diego has discovered that oxygen-poor regions of tropical oceans are expanding as the oceans warm, limiting the areas in which predatory fishes and other marine organisms can live or enter in search of food.

The new study is led by Lothar Stramma from the Leibniz Institute of Marine Sciences (IFM-GEOMAR) in Kiel, Germany, and is co-authored by Janet Sprintall, a physical oceanographer at Scripps Oceanography and others. The researchers found through analysis of a database of ocean oxygen measurements that levels in tropical oceans at a depth of 300 to 700 meters (985 to 2,300 feet) have declined during the past 50 years. The ecological impacts of this increase could have substantial biological and economical consequences.

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Mean dissolved oxygen concentrations in the world’s oceans at a depth of 400 meters (1,312 feet) with blue contours representing the lowest concentrations. Boxed areas represent ocean regions analyzed in the study. Image courtesy of AAAS/Science

“We found the largest reduction in a depth of 300 to 700 meters (985 to 2,300 feet) in the tropical northeast Atlantic, whereas the changes in the eastern Indian Ocean were much less pronounced,” said Stramma. “Whether or not these observed changes in oxygen can be attributed to global warming alone is still unresolved. The reduction in oxygen may also be caused by natural processes on shorter time scales.”

Sprintall said the oxygen-poor areas have the potential to move into coastal areas via currents that flow from the mid-depth tropical oceans, where the oxygen changes were observed, and along the west coast of continents.

“The width of the low-oxygen zone is expanding deeper but also shoaling toward the ocean surface,” said Sprintall, a specialist in observing changes of fluxes in ocean properties such as heat distribution.

Sprintall contributed data to the study gathered during recent cruises undertaken as part of the Climate Variability and Predictability (CLIVAR) program, a long-running study operated by the World Climate Research Programme that seeks to understand climate through ocean-atmosphere interactions.

The study, “Expanding Oxygen-Minimum Zones in the Tropical Oceans,” appears in the May 2 edition of the journal Science. The research team includes Stramma, Sprintall, NOAA scientist Gregory Johnson, and Volker Mohrholz from the Institute for Baltic Sea Research in Warnemünde, Germany.

The team selected ocean regions for which they could obtain the greatest amount of data to document the decline in oxygen. Some of the more recent data came from oxygen sensors which have been added to about 150 of the profiling floats used in Argo, a worldwide network of sensors that track basic ocean conditions such as temperature and salinity. There are more than 3,000 Argo floats operating in the world’s oceans, and Sprintall said the quality of the data gathered by the Argo floats suggests that more units in the network should be outfitted with oxygen sensors.

Lisa Levin, a biological oceanographer at Scripps Oceanography who studies oxygen-minimum zones that intercept the seafloor, said an expansion of oxygen-minimum zones in the oceans could lead to diminished biodiversity and to the expanded distributions of organisms that have adapted to live in hypoxic, or oxygen-poor waters.

“I think it’s uncharted territory,” said Levin, who was not affiliated with the study. “Thicker oxygen minimum zones could affect nutrient cycling, predator-prey relationships and plankton migrations. Where the expanding oxygen-minimum zones impinge on continental margins, we could see huge ecosystem changes.”

The results of the study are an important milestone for the ongoing work of the new Collaborative Research Centre (SFB 754) “Climate – Biogeochemistry Interactions in the Tropical Ocean” funded by the German Research Foundation, which started its first phase in January 2008 in close cooperation with the University of Kiel. The SFB aims to better define the interactions between climate and biogeochemistry on a quantitative basis.

source:http://yubanet.com

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Unmanned aircraft to study Southern California smog and its consequences

Posted on May 11, 2008 by Rashid Faridi
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Using sophisticated unmanned aircraft, research scientists at Scripps Institution of Oceanography, UC San Diego hope to assess Southern California’s potential for climate change and better understand the sources of air pollution.

Funded by the California Energy Commission, the California AUAV Air Pollution Profiling Study (CAPPS) uses autonomous unmanned aerial vehicles (AUAVs) to gather meteorological data as the aircraft fly through clouds and aerosol masses in Southern California skies. The flights will take place at Edwards Air Force Base near Rosamond. The study began its first sortie of data-gathering flights in April 2008.

Scripps Atmospheric and Climate Sciences Professor V. Ramanathan, CAPPS’ lead scientist, said the characteristics of Southern California climate and meteorology – ranging from its dry weather to its tendency to trap rather than export smog – could make it especially prone to climate change consequences of air pollution such as accelerated snowmelt and dimming at ground level.

“These monthly UAV flights will provide unprecedented data for evaluating how long range transport of pollutants including ozone, soot and other particulates from the northwest United States, Canada, east Asia and Mexico mix with local pollution and influence our air quality and regional climate including the early melting of snow packs,” said Ramanathan.

Data collection began on April 2, 2008 and will continue through January 2009, offering researchers a chance to view seasonal variations in air pollution.

Ramanathan’s team revolutionized the gathering of atmospheric data in 2006 when the researchers first successfully deployed the aircraft in the Maldives AUAV Campaign (MAC). Miniaturized instruments on the aircraft, which typically flew in formations of three, measured a range of properties such as the quantity and size of the aerosols on which cloud droplets form. The instruments also recorded variables such as temperature, humidity and the intensity of light that permeates clouds and masses of smog. It was the first time such comprehensive measurements were made at a cost that was very low relative to traditional manned flights.

The Scripps researchers have used data from MAC and other field campaigns to observe that a pervasive mass of air pollution in south and east Asia, commonly referred to as the “atmospheric brown cloud,” can disrupt rainfall patterns and cause cooling at ground level but warming at higher altitudes. The cloud typically contains a mix of dust, sulfates and soot and other forms of black carbon. These aerosols are primarily the products of diesel combustion, agricultural biomass burning, use of wood- and cow dung-burning stoves in rural homes and the use of coal in home heating. Ramanathan and his team linked the brown cloud to an observed acceleration of glacial melt in the Himalayas. Himalayan glaciers provide billions of people in Asia with their drinking water.

In CAPPS, the Scripps team hopes to determine how much of Southern California’s air pollution comes from Asia, Mexico and from regions north of California. Scientists routinely observe aerosol masses traveling across the Pacific Ocean to the West Coast but are still trying to understand the effects of that pollution. The imported smog is only one of several sources of atmospheric aerosols in Southern California, joining local auto and industrial emissions and smoke from wildfires. Researchers have seen evidence that this air pollution can mix with falling snow and accelerate its melt when sunlight hits and warms the “dirty” snow in mountain watersheds.

“Black carbon and ozone are two major contributors to global warming, next to carbon dioxide,” said Ramanathan. “We hope to document the vertical profiles of black carbon and ozone and their climate warming effects for the first time over California, and this data will likely help California reduce its global warming commitment.”

The California Energy Commission’s Public Interest Energy Research (PIER) program will employ CAPPS results in an analysis of the potential future economic and ecological consequences of Southern California air pollution. Scientists also hope to combine CAPPS results with satellite data to better understand the role of aerosols at a larger regional scale.

“As we learn more about the air we breathe and seek solutions to reduce greenhouse gases, this important atmospheric research will help us address the serious challenges to California’s water resources, ecology, and the health of our residents,” said Energy Commissioner Arthur Rosenfeld. “With this study, California continues to demonstrate its commitment as a national leader in climate change research.”

The aircraft will profile atmospheric conditions at altitudes ranging between 2,000 and 12,000 feet. Because of Federal Aviation Administration regulations that prohibit unmanned aircraft from flying in public airspace, the flight paths will be limited to military airspace, which is exempted from FAA rules. The researchers hope to conduct the flights at least once a month or as often as every two weeks. The Scripps team also hopes to gather data on a situational basis such as during wildfires.

source:http://yubanet.com

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Big-Bang

Posted on May 11, 2008 by Rashid Faridi

THE BIG BANG:

It sure was BIG!!

The Hubble Telescope’s deepest view of the universe teaches us about the beginning

INTRODUCTION

We certainly know that our universe exists, however, this knowledge alone has not satisfied mankind’s quest for further understanding. Our curiosity has led us to question our place in this universe and furthermore, the place of the universe itself. Throughout time we have asked ourselves these questions: How did our universe begin? How old is our universe? How did matter come to exist? Obviously, these are not simple questions and throughout our brief history on this planet much time and effort has been spent looking for some clue. Yet, after all this energy has been expended, much of what we know is still only speculation.

We have, however, come a long way from the mystical beginnings of the study of cosmology and the origins of the universe. Through the understandings of modern science we have been able to provide firm theories for some of the answers we once called hypotheses. True to the nature of science, a majority of these answers have only led to more intriguing and complex questions. It seems to be inherent in our search for knowledge that questions will always continue to exist.

Although in this short chapter it will be impossible to tackle all of the questions concerning the creation of everything we know as reality, an attempt will be made to address certain fundamental questions of our being. It will be important to keep in mind that all of this information is constantly being questioned and reevaluated in order to understand the universe more clearly. For our purposes, through an examination of what is known about the Big Bang itself, the age of the universe, and the synthesis of the first atoms, we believe that we can begin to answer several of these key questions.

THE BIG BANG

One of the most persistently asked questions has been: How was the universe created? Many once believed that the universe had no beginning or end and was truly infinite. Through the inception of the Big Bang theory, however,no longer could the universe be considered infinite. The universe was forced to take on the properties of a finite phenomenon, possessing a history and a beginning.

About 15 billion years ago a tremendous explosion started the expansion of the universe. This explosion is known as the Big Bang. At the point of this event all of the matter and energy of space was contained at one point. What exisisted prior to this event is completely unknown and is a matter of pure speculation. This occurance was not a conventional explosion but rather an event filling all of space with all of the particles of the embryonic universe rushing away from each other. The Big Bang actually consisted of an explosion of space within itself unlike an explosion of a bomb were fragments are thrown outward. The galaxies were not all clumped together, but rather the Big Bang lay the foundations for the universe.

The origin of the Big Bang theory can be credited to Edwin Hubble. Hubble made the observation that the universe is continuously expanding. He discovered that a galaxys velocity is proportional to its distance. Galaxies that are twice as far from us move twice as fast. Another consequence is that the universe is expanding in every direction. This observation means that it has taken every galaxy the same amount of time to move from a common starting position to its current position. Just as the Big Bang provided for the foundation of the universe, Hubbles observations provided for the foundation of the Big Bang theory.

Since the Big Bang, the universe has been continuously expanding and, thus, there has been more and more distance between clusters of galaxies. This phenomenon of galaxies moving farther away from each other is known as the red shift. As light from distant galaxies approach earth there is an increase of space between earth and the galaxy, which leads to wavelengths being stretched.

In addition to the understanding of the velocity of galaxies emanating from a single point, there is further evidence for the Big Bang. In 1964, two astronomers, Arno Penzias and Robert Wilson, in an attempt to detect microwaves from outer space, inadvertently discovered a noise of extraterrestrial origin. The noise did not seem to emanate from one location but instead, it came from all directions at once. It became obvious that what they heard was radiation from the farthest reaches of the universe which had been left over from the Big Bang. This discovery of the radioactive aftermath of the initial explosion lent much credence to the Big Bang theory.

Even more recently, NASAs COBE satellite was able to detect cosmic microwaves eminating from the outer reaches of the universe. These microwaves were remarkably uniform which illustrated the homogenity of the early stages of the universe. However, the satillite also discovered that as the universe began to cool and was still expanding, small fluctuations began to exist due to temperature differences. These flucuatuations verified prior calculations of the possible cooling and development of the universe just fractions of a second after its creation. These fluctuations in the universe provided a more detailed description of the first moments after the Big Bang. They also helped to tell the story of the formation of galaxies which will be discussed in the next chapter.

The Big Bang theory provides a viable solution to one of the most pressing questions of all time. It is important to understand, however, that the theory itself is constantly being revised. As more observations are made and more research conducted, the Big Bang theory becomes more complete and our knowledge of the origins of the universe more substantial.

THE FIRST ATOMS

Now that an attempt has been made to grapple with the theory of the Big Bang, the next logical question to ask would be what happened afterward? In the minuscule fractions of the first second after creation what was once a complete vacuum began to evolve into what we now know as the universe. In the very beginning there was nothing except for a plasma soup. What is known of these brief moments in time, at the start of our study of cosmology, is largely conjectural. However, science has devised some sketch of what probably happened, based on what is known about the universe today.

Immediately after the Big Bang, as one might imagine, the universe was tremendously hot as a result of particles of both matter and antimatter rushing apart in all directions. As it began to cool, at around 10^-43 seconds after creation, there existed an almost equal yet asymmetrical amount of matter and antimatter. As these two materials are created together, they collide and destroy one another creating pure energy. Fortunately for us, there was an asymmetry in favor of matter. As a direct result of an excess of about one part per billion, the universe was able to mature in a way favorable for matter to persist. As the universe first began to expand, this discrepancy grew larger. The particles which began to dominate were those of matter. They were created and they decayed without the accompaniment of an equal creation or decay of an antiparticle.

As the universe expanded further, and thus cooled, common particles began to form. These particles are called baryons and include photons, neutrinos, electrons and quarks would become the building blocks of matter and life as we know it. During the baryon genesis period there were no recognizable heavy particles such as protons or neutrons because of the still intense heat. At this moment, there was only a quark soup. As the universe began to cool and expand even more, we begin to understand more clearly what exactly happened.

After the universe had cooled to about 3000 billion degrees Kelvin, a radical transition began which has been likened to the phase transition of water turning to ice. Composite particles such as protons and neutrons, called hadrons, became the common state of matter after this transition. Still, no matter more complex could form at these temperatures. Although lighter particles, called leptons, also existed, they were prohibited from reacting with the hadrons to form more complex states of matter. These leptons, which include electrons, neutrinos and photons, would soon be able to join their hadron kin in a union that would define present-day common matter.

After about one to three minutes had passed since the creation of the universe, protons and neutrons began to react with each other to form deuterium, an isotope of hydrogen. Deuterium, or heavy hydrogen, soon collected another neutron to form tritium. Rapidly following this reaction was the addition of another proton which produced a helium nucleus. Scientists believe that there was one helium nucleus for every ten protons within the first three minutes of the universe. After further cooling, these excess protons would be able to capture an electron to create common hydrogen. Consequently, the universe today is observed to contain one helium atom for every ten or eleven atoms of hydrogen.

While it is true that much of this information is speculative, as the universe ages we are able to become increasingly confident in our knowledge of its history. By studying the way in which the universe exists today it is possible to learn a great deal about its past. Much effort has gone into understanding the formation and number of baryons present today. Through finding answers to these modern questions, it is possible to trace their role in the universe back to the Big Bang. Subsequently, by studying the formation of simple atoms in the laboratory we can make some educated guesses as to how they formed originally. Only through further research and discovery will it be possible to completely understand the creation of the universe and its first atomic structures, however, maybe we will never know for sure.

AGE OF THE UNIVERSE

We now have something of a handle on two of the most important quandaries concerning the universe; however, one major question remains. If the universe is indeed finite, how long has it been in existence? Again, science has been able to expand upon what it knows about the universe today and extrapolate a theory as to its age. By applying the common physical equation of distance over velocity equaling time, which again uses Hubbles observations, a fairly accurate approximation can be made.

The two primary measurements needed are the distance of a galaxy moving away from us and that galaxys red shift. An unsuccessful first attempt was made to find these distances through trigonometry. Scientists were able to calculate the diameter of the Earths orbit around the sun which was augmented through the calculation of the Suns motion through our own galaxy. Unfortunately, this calculation could not be used alone to determine the enormous distance between our galaxy and those which would enable us to estimate the age of the universe because of the significant errors involved.

The next step was an understanding of the pulsation of stars. It had been observed that stars of the same luminosity blinked at the same rate, much like a lighthouse could work where all lighthouses with 150,000 watt light bulbs would rotate every thirty seconds and those with 250,000 watt light bulbs would rotate every minute. With this knowledge, scientists assumed that stars in our galaxy that blinked at the same rate as stars in distant galaxies must have the same intensity. Using trigonometry, they were able to calculate the distance to the star in our galaxy. Therefore, the distance of the distant star could be calculated by studying the difference in their intensities much like determining the distance of two cars in the night. Assuming the two cars headights had the same intensity, it would be possible to infer that the car whose headlights appeared dimmer was farther away from the observer than the other car whose headlights would seem brighter. Again, this theory could not be used alone to calculate distance of the most far-away galaxies. After a certain distance it becomes impossible to distinguish individual stars from the galaxies in which they exist. Because of the large red shifts in these galaxies a method had to be devised to find distance using entire galaxy clusters rather than stars alone.

By studying the sizes of galaxy cluster that are near to us, scientists can gain an idea of what the sizes of other clusters might be. Consequently, a prediction can be made about their distance from the Milky Way much in the same way the distance of stars was learned. Though a calculation involving the supposed distance of the far-off cluster and its red shift, a final estimation can be made as to how long the galaxy has been moving away from us. In turn, this number can be used inversely to turn back the clock to a point when the two galaxies were in the same place at the same time, or, the moment of the Big Bang. The equation generally used to show the age of the universe is shown here:

(distance of a particular galaxy) / (that galaxys velocity) = (time)

or

4.6 x 10^26 cm / 1 x 10^9 cm/sec = 4.6 x 10^17 sec

This equation, equaling 4.6 x 10^17 seconds, comes out to be approximately fifteen billion years. This calculation is almost exactly the same for every galaxy that can be studied. However, because of the uncertainties of the measurements produced by these equations, only a rough estimate of the true age of the universe can be fashioned. While finding the age of the universe is a complicated process, the achievement of this knowledge represents a critical step in our understanding.

NOW WHAT?

In summary, we have made a first attempt at explaining the answers that science has revealed about our universe. Our understanding of the Big Bang, the first atoms and the age of the universe is obviously incomplete. As time wears on, more discoveries are made, leading to infinite questions which require yet more answers. Unsatisfied with our base of knowledge research is being conducted around the world at this very moment to further our minimal understanding of the unimaginably complex universe.

Since its conception, the theory of the Big Bang has been constantly challenged. These challenges have led those who believe in the theory to search for more concrete evidence which would prove them correct. From the point at which this chapter leaves off, many have tried to go further and several discoveries have been made that paint a more complete picture of the creation of the universe.

Recently, NASA has made some astounding discoveries which lend themselves to the proof of the Big Bang theory. Most importantly, astronomers using the Astro-2 observatory were able to confirm one of the requirements for the foundation of the universe through the Big Bang. In June, 1995, scientists were able to detect primordial helium, such as deuterium, in the far reaches of the universe. These findings are consistent with an important aspect of the Big Bang theory that a mixture of hydrogen and helium was created at the beginning of the universe.

In addition, the Hubble telescope, named after the father of Big Bang theory, has provided certain clues as to what elements were present following creation. Astronomers using Hubble have found the element boron in extremely ancient stars. They postulate that its presence could be either a remnant of energetic events at the birth of galaxies or it could indicate that boron is even older, dating back to the Big Bang itself. If the latter is true, scientists will be forced once again to modify their theory for the birth of the universe and events immediately afterward because, according to the present theory, such a heavy and complex atom could not have existed.

In this manner we can see that the research will never be truly complete. Our hunger for knowledge will never be satiated. So to answer the question, what now, is an impossibility. The path we take from here will only be determined by our own discoveries and questions. We are engaged in a never-ending cycle of questions and answers where one will inevitably lead to the other.

COBE continues to search the outer reaches of the universe

DEEP THOUGHTS

It is extremely difficult to separate this subject of science from daily existential pondering. Everyone at some point in time has grappled with the question of why we are here? Some have found refuge in the sheer philosophic nature of this question while others have taken a more scientific approach. These particular wanderers have taken the question to a higher level, concentrating not only on human existence but the existence of everything we know as real.

If you sit and try to imagine the whole of the entire universe it would be mind-boggling. However, science has now told us that the universe is, in fact, finite, with a beginning, a middle, and a future. It is easy to get caught up in the large scale of the issue in discussing years by the billions, yet, this time still passes. As we travel through our own lives here on Earth, we also travel through the life of our universe.

In this chapter, we have made some attempts to explain this journey. It is odd that we will never truly know how it began. We can only speculate and give our best guess. Through our own devices we have been able to produce evidence that these guesses are close to the truth. But centuries from now, will the human race compare us to those who once thought of the Earth as the center of the universe?

GLOSSARY

Baryons– common particles including photons and neutrinos created at approximately 10^-33 seconds after the Big Bang

Deuterium– a heavy isotope of hyrogen containing on proton and one neutron

Hadrons– composite particles such as protons and neutrons forming after the temperature drops to 300 MeV

Leptons– light particles existing with hadros including electrons, neutrinos and photons

Red Shift– shift toward the red in the spectra of light reaching us from the stars in distant galaxies

Tritium– transitional element between deuterium and the formation of a helium nucleus

REFERENCES

Literature

Kaufmann, William J., III. Galaxies and Quasars. San Fransisco: W.H. Freeman and Company, 1979.

Silk, Joseph. A Short History of the Universe. New York: Scientific American Library, 1994.

Taylor, John. When the Clock Struck Zero. New York: St. Martins Press, 1993.

Trinh, Xuan Thuan. The Birth of the Universe: The Big Bang and After. New York: Harry N. Abrams, Inc., 1993.

World Wide Web

NASA

http://spacelink.msfc.nasa.gov –

/Educational.Services/Educational.Publications/Educational.Horizons.Newsletter/ 92-01-01.Vol.1.No.1

/NASA.News/NASA.News.Releases /95.Press.Releases/95-06.News.Releases/95-06-12.Primordial.Helium.Detected

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Drinking and Islam

Posted on May 10, 2008 by Rashid Faridi

a) Drink essential. Drink is essentially necessary for everything in the world as without it nothing can live. Plants die without watery nourishment. Man is also not free from that law. The Quran says: And Allah created every living thing from water (25:4)

b) Manner of Drink. Drinking should always be made in sitting posture and not in standing or lying condition. The Holy Prophet prohibited it (11:78). Before drinking, the name of Allah should be taken by uttering – “In the name of Allah, the Most Merciful and Beneficent, “and after drink the Almighty Allah should be praised by saying “All Praise if for Allah, the lord of the worlds” (11:89). “At the time of actual drink, no breath should be thrown into the cup or vessel (7:44, 11:88) and generally water should be taken in three breaths (11:75) Drink during actual eating should be avoided as far as possible, but it should be finishing touch to meal.

c) Kinds of Drink. There are various kinds of drink in the world, some are lawful and some unlawful. Of the lawful drinks, the Holy Prophet loved sweet cool drink very much (11:93). The drink of milk and honey were also greatly in favour with him. The usefulness of milk both as drink and food has been guaranteed by the Quran. “And We give you to drink of what is in their bellies from between the faces and blood – pure milk very agreeable for those who drink” (16:66).

d) Drinking of Juices of Fruits and Leaves. With regret to punishment and sin of unlawful drinks such as wine and other intoxicating liquors, they have been dealt with in notes 1218 and 1219*. Anything intoxicants and games of chance Say: In both of them, there is a great sin and mean of profit for men, and their sin is greater then their profit (2:219). This word is sufficient enough to abolish the age long custom of Arabs in drinking intoxicants. It is said that when wine was prohibited, the streets of Medina were flooded with wines and bottles. There are four prohibited intoxicants. (1) Khamar i.e., crude juice of the grapes which being fermented becomes intoxicating. Khamar is produced from two trees, namely vine and date. It is unlawful in its small and great quantities. It is also unlawful to derive any use from khamar (wine) either as a medicine or in any manner, because the use of filth is forbidden. (2) The second prohibited liquor is the boiled juice of grapes called Bazik and Monissaf. The juice of grapes when boiled until a quantity less than two thirds evaporate is called Bazik and when it is evaporated to the extent of one half, it is called Monissaf. (3) The third kind of prohibited liquor is Sikkar and is made by steeping fresh dates in water until they take effect in sweetening it. (4) The fourth kind is Nookoo Zaheeb which is water in which raisins are steeped until it becomes sweet. This is prohibited when it becomes spirituous.

source:http://haseembhai.blogspot.com/

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