Carnivore Species Shrank During Global Warming Event
Posted: August 31, 2010 Filed under: BIODIVERSITY, Global Warming Leave a comment »
A new University of Florida study indicates extinct carnivorous mammals shrank in size during a global warming event that occurred 55 million years ago.The study, scheduled to appear in the December print edition of the Journal of Mammalian Evolution and now available online, describes a new species that evolved to half the size of its ancestors during this period of global warming.
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Drainage Basin
Posted: August 30, 2010 Filed under: water Leave a comment »
The land based part of the hydrological cycle is called the Drainage Basin System. A drainage basin is the name given to the area of land which is drained by a river. When water reaches the surface there are a number of routes which it may take in its journey to reach the river. These are shown in the diagram .
Drainage Basins have a number of distinct features . The edge of a drainage basin is characterised by the highest points of land around the river, this is known as the watershed. The point at which a river starts is called its source. As the river continues to flow down stream it may be joined by smaller rivers called tributaries. The point at which these smaller rivers join the main river is known as a confluence. As the river continues its journey, eventually reaches the sea – the point where the river flows into the sea is known as the river mouth.
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New View of Tectonic Plates Through Computer Modeling of Earth’s Mantle Flow, Plate Motions, and Fault Zones
Posted: August 30, 2010 Filed under: earth, plate tectonics Leave a comment »
Plate boundaries, which can be seen as narrow red lines are resolved using an adaptively refined mesh with 1km local resolution. Shown are the Pacific and the Australian tectonic plates and the New Hebrides and Tonga microplates. (Credit: Georg Stadler, Institute for Computational Engineering & Sciences, UT Austin)
Computational scientists and geophysicists at the University of Texas at Austin and the California Institute of Technology (Caltech) have developed new computer algorithms that for the first time allow for the simultaneous modeling of Earth’s mantle flow, large-scale tectonic plate motions, and the behavior of individual fault zones, to produce an unprecedented view of plate tectonics and the forces that drive it.
A paper describing the whole-earth model and its underlying algorithms will be published in the August 27 issue of the journal Science and also featured on the cover.The work “illustrates the interplay between making important advances in science and pushing the envelope of computational science.
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Sinabung erupts in Sumatra
Posted: August 29, 2010 Filed under: Volcanoes Leave a comment »
Mount Sinabung volcano on Sumatra erupted shortly after midnight local time on 29 August 2010, producing lava and throwing ash 1500 metres above the summit. Local inhabitants fleeing their homes have spoken of ’thick black smoke, small stones and sulphur’ being produced by the volcano, according to AFP: one local man reportedly died as a result of breathing difficulties suffered during the eruption.
Mount Sinabung is a 2460-metre stratovolcano in northern Sumatra, about 60 km SW of the city of Medan. An uncertain eruption is given by the Global Volcanism Program for 1881 and sulphurous gas emissions were apparently reported from the summit in 1912, but there are no historical records of confirmed eruptive activity.
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Gems and The Moh’s Scale
Posted: August 29, 2010 Filed under: Uncategorized Leave a comment »
In the old days, people believed gems held magical powers. Gems are very valuable.
Diamond is the hardest naturally occurring substance with a hardness of 10. Its crystal system is cubic because it has 4 equidistant neighboring crystals. Its specific gravity is 3.5. The word diamond means adamas in Greek, meaning “unconquerable”. That’s why Napoleon wanted the Regent, or Pitt diamond set into the hilt of his sword.
Topaz-the name for this substance is a misnomer. The word topaz actually means Zabargad in Greek, which is an island in the Red Sea, a source of peridot. Topaz’s crystal structure is orthorhombic. The hardness of topaz is 8, though it can be broken easily due to its 1 perfect direction of cleavage. The specific gravity is 3.52-3.56, which is very close to diamond’s.
Tourmaline is a very interesting gem. It has a trigonal crystal system and a hardness of 7-7.5. Its specific gravity is 3-3.25. What is really interesting is that if this gem was heated, one side would be positively charged, the other negatively. That’s why there is a watermelon tourmaline. Since it can produce electricity, it has a tendency to attract dust.
Quartz is really just silicon dioxide. Quartz is an igneous rock and its hardness is 7. Its crystal system is trigonal and its specific gravity is 2.65. Quartz is hard to break and has no cleavage. Quartz is the main percentage of dust. Therefore, dust can damage gems with a hardness of 6.99 and lower. Quartz is only pure when it is colorless. Rose quartz has iron and titanium too. Smoky quartz has aluminum.
The Moh’s Scale
The Moh’s Scale is the scale that organizes the rocks in order of hardness with 10 being the hardest and 1 the softest. In other words, diamond is the hardest and talc is the softest. This is an easy way to see which rocks are harder than others.
The Moh’s Scale is not to scale though. Diamond is a lot harder than corundum but corundum isn’t much harder than quartz.
1. Talc
2. Gypsum
3. Calcite
4. Flourite
5. Apatite
6. Orthoclase
7. Topaz
8. Quartz
9. Corundum
10. Diamond
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10 Types of Shelters for Natural Disasters
Posted: August 28, 2010 Filed under: Guest Post Leave a comment »Guest Post by Brenda Chapman
When a natural disaster strikes, there’s nothing people want more than the bare necessities and a roof over their heads. Disaster relief groups go to great lengths to ensure that victims have shelter from the storm and a place to dwell during the aftermath, but when facilities become full the help has to get creative. Thankfully, there are hundreds of affordable shelters on the market and self-build homes that provide shelter and hope in these trying times. Here are 10 types of shelters for natural disasters:
Shipping Container Houses
In recent years, recycled shipping containers have been used as emergency housing for natural disaster victims. Shipping containers have a sturdy structure and impenetrable exterior that makes them an ideal shelter for earthquakes, hurricanes and other natural disasters. Not only are they structurally-sound and plentiful, but shipping containers make beautiful, modular homes.
Relief Tents
Disaster relief tents are convenient, portable and easy-to-install structures that use strong frames and high-quality fabrics that are flame retardant, water resistant and give victims privacy. Tents can typically house an entire family or a group of individuals with enough space to create separate rooms. Depending on the construction and materials used, some disaster tents are capable of withstanding severe weather and certain natural disasters.
Shelter Canopies
Shelter canopies aren’t just four poles with an overhead roof, they can also come with windows, doors and protective lining that shields victims from water, bugs and other outside elements. Canopies are extremely portable and rapidly deployed in times of need. Although canopies are mostly temporary houses, they can be customized with generators, lights, beds, tables and other amenities to make it feel like home.
Foldable Shelters
Like the bellows of an accordion, foldable shelters expand into homes of various shapes and sizes and easily fold back into place to be transported or stowed away. Foldable shelters are typically made out of polypropylene, provide relief for four or more people and are relatively inexpensive to buy. The unique folding design of this shelter makes it one of the most portable and immediate shelters for natural disaster victims today.
Plastic Sheeting Homes
Many temporary houses for natural disaster victims are made from high-quality plastic sheeting, which is portable, long-lasting, and shields against weather and other elements. Plastic sheeting can be used alone to create single-family homes, community shelters, latrines or to reinforce current housing.
Sandbag Shelters
Sandbag shelters are both sturdy and artistic structures that can resist hurricanes, earthquakes and floods. Sandbag shelters are extremely versatile in their shape, construction and amenities. Mirroring the adobe-style homes, sandbag shelters can be used as temporary shelters or transformed into self-sustaining houses.
Hexayurt Shelters
For less than $100 dollars to build, hexayurt homes provide an inexpensive, eco-friendly and sustainable form of shelter for natural disaster victims. This geometric shaped shelter can be made with sheets of plywood, OSB, coroplast, hexacomb cardboard and other construction materials that are screwed together, painted and customized to your liking. They are roomy enough for windows, doors, stove fittings and room partitions and have the ability to withstand various climates and weather conditions for years.
Bamboo Houses
Bamboo houses have become a widely-recognized form of shelter for natural disaster victims and those who are prone to such catastrophes. Bamboo is incredibly flexible and strong, with twice the compression strength of concrete and half the tensile strength of steel. If properly constructed and treated, bamboo houses have the power to withstand deadly earthquakes, typhoons and other natural disasters.
InterShelter
InterShelters are dome-shaped homes, made out of a fiberglass-composite mixture and a fireproof structure. They can house an entire family and are easily broken down, rebuilt and relocated for various shelter needs. Each dome-home weighs 70 pounds, but they can withstand a Category 4 hurricane, an 8.5-magnitude earthquake and other extreme weather or natural disasters.
Concrete Shelters
In an effort to create permanent housing during natural disaster crises, the Concrete Canvas created a building-in-a-bag that only needs water and air to inflate. This portable shelter is made of cement-impregnated cloth expands and hardens in one day and is completely waterproof, fireproof and chemically resistant. Doors and windows can be cut for ventilation, and any unset cloth can be tailored to meet the occupants’ needs.
first published here
North American Continent Is a Layer Cake, Scientists Discover
Posted: August 27, 2010 Filed under: earth, plate tectonics Leave a comment »
The North American continent is not one thick, rigid slab, but a layer cake of ancient, 3 billion-year-old rock on top of much newer material probably less than 1 billion years old, according to a new study by seismologists at the University of California, Berkeley.The finding, which is reported in the Aug. 26 issue of Nature, explains inconsistencies arising from new seismic techniques being used to explore the interior of the Earth, and illuminates the mystery of how the Earth’s continents formed.
This graphic shows the thickness (in kilometers) of the North American lithosphere. The blue area is about 250 km thick and, based on new findings reported in Nature, is composed of a 3-billion-year old craton underlain by younger lithosphere deposited as ocean floor subducted under the continent within the past billion years. The green, yellow and red areas are younger and thinner continental lithosphere added around the margins of the original craton, also by subducting sea floor. The thick broken line indicates the borders of the stable part of the continent. (Credit: Barbara Romanowicz and Huaiyu Yuan, UC Berkeley)
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Water wars: India, China & the Great Thirst
Posted: August 26, 2010 Filed under: India, water Leave a comment »
Dear Readers
Found this thought provoking piece here and thought of sharing with you all.Enjoy
Countries might wage wars over oil but the most valuable resource in the world is water. It’s the new oil, the colourless gold that’s at a premium because it is becoming scarce.
wday’s nightmare is that tomorrow the glass will be empty because water supplies are fast evaporating on account of population pressures, urbanization and now, climate change. No country is likely to be left untouched, but the great thirst will be felt the most in the region that has the world’s two most populous countries – India and China.
A new study says the situation will be the bleakest in the basins of major Himalayan rivers, ie our own backyards. The study by the Strategic Foresight Group (SFG), Mumbai is titled ‘The Himalayan Challenge’ and frighteningly predicts that “in the next 20 years, the four countries in the Himalayan sub-region (India, Nepal, China, Bangladesh) will face the depletion of almost 275 billion cubic metres of annual renewable water. For comparison, this is more than the total amount of water available in…Nepal at present.”
But why must this region run dry? It is fed by major rivers such as the Yangtze, Indus, Ganges and the Brahmaputra. But the problem is all of them originate in the Tibetan Plateau and will be badly affected by melting glaciers. The report says it may all end very badly because a water deficit will have a cumulative, destructive effect on agricultural production, power generation, food availability and livelihood, forcing all four countries in the sub-region to try and secure water resources. They may even look beyond their borders, leading to geo-political tension.
The point here is interesting. There are global forums that deliberate on oil prices and availability, but disputes over water are generally handled regionally or bilaterally. Sundeep Waslekar, executive director of the SFG laments the basic truth that “there are no global treaties on water. Only 17 nations (which don’t include the four aforementioned) have signed the UN convention on non-navigational uses of international water courses, 1997 (which provides a mechanism to deal with trans-border waters).”
India has bilateral agreements on water. Treaties with Nepal and Bangladesh cover development of the Mahakali river and sharing the waters of the Ganga. But New Delhi has nothing like that with Beijing. If today’s legal and policy architecture were used to deal with any future water dispute, India and China would have nothing more to look to than a couple of MoUs on sharing flood-season hydrological data on the Yarlong Tsangpo/Brahmaputra and the Sutlej/Langquin Zangbu rivers. Former water secretary Ramaswamy Iyer agrees that there is a chasm where there should be formal agreement. Until some years ago, water did not even figure in talks between India and China, he points out.
Retired Colonel P K Gautam, research fellow at the Institute for Defence Studies and Analyses, adds that “if China builds a dam on the Brahmaputra now, and we complain about lesser water flows later, it could say that India doesn’t have any projects in the northeast.”
Add to this the current problem of massive water shortages in both countries. This could force both India and China to “securitize” water sources and lead to tension. India is already worried about China’s reported plans to construct a massive 40,000 MW dam at the point where the Brahmaputra takes a U-bend to enter India. Delhi is also concerned about Beijing planning to divert Brahmaputra waters towards China’s arid north.
But B G Verghese, visiting professor at the Centre for Policy Research, says fears about the diversion of water are “highly exaggerated” because the difficult terrain makes it all but impossible to do this.
Waslekar agrees, but says that’s a reprieve that will only last 15 years at the most. He says it could be a window of opportunity, especially as “China’s attitude has changed a little bit, especially towards the Mekong river basin on which it had earlier refused to share data with other affected nations. … it is showing some kind of openness.” So should India try and make joint plans with China for hydropower development and setting up stations in glacial areas to monitor their melting?
Yes, says Gautam. “India should negotiate with China. We need data on the quantum of water flow in the Brahmaputra, on the melting of glaciers.”
The SFG report suggests creating a new regional forum, say a Himalayan rivers commission, to better manage the looming water problem. But like much else, that’s difficult in a region dominated by the trust deficit between countries. The key lies in doing something before the rivers run dry and the taps as well.
Ocean pH
Posted: August 25, 2010 Filed under: oceans Leave a comment »
Ocean acidification is the name given to the ongoing decrease in the pH of the Earth’s oceans, caused by their uptake of atmospheric carbon dioxide. Between 1751 and 1994 surface ocean pH is estimated to have decreased from approximately 8.18 to 8.1. PH is a measure of the acidity or basicity of a solution. It approximates but is not equal to concentration of hydrogen ions expressed on a logarithmic scale. A low pH indicates a high concentration of hydrogen ions, while a high pH indicates a low concentration. A strong acid would be less than 1 on this scale. A recent study indicates the relative impact on future ocean acidification of different aspects of global climate change mitigation policies such as the year that global emissions peak.
The absorption of CO2 by water results in the formation of acid (carbonic acid) which is similar in concept to acid rain.
Although the natural absorption of CO2 by the world’s oceans helps to mitigate the climatic effects of high CO2, it is believed that the resulting decrease in pH will have negative consequences, primarily for marine life used to a certain pH level that use CO2 to build carbonate shells. These span the food chain from autotrophs to heterotrophs and include organisms such as coccolithophores, corals, foraminifera, echinoderms, crustaceans and molluscs.
Aside from calcification, organisms may suffer other adverse effects, either directly as reproductive or physiological effects, or indirectly through negative impacts on food resources. Marine life will change as pH levels change. As of yet, there is no complete understanding of the overall effects.
In the Geophyswical Research Letters (VOL. 37, L15704, 5 PP., 2010), there is an article on the influence of environmental mitigation policy on ocean pH changes.
Relative to a scenario where CO2 emissions peak in 2016 and then decrease by 1% per year tend to lead to the same or current pH by 2100. No CO2 emission reduction leads to a decrease of global mean ocean surface pH to 7.67 to 7.81 in the same time frame.
If emissions are capped for example in 2016 and then reduced by 5% per year, ocean pH may be limited to a minimum of 8.02. This is still more acidic than the nineteenth century’s pH level but better than the worse case projected in these computer simulations.
Unfortunately, the buffering capacity of the oceans is really not known, What is clear is that the ocean’s pH is going down.
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Deepwater Oil Plume in Gulf Degraded by Microbes, Study Shows
Posted: August 25, 2010 Filed under: BIODIVERSITY, Ecosystem, Environment Leave a comment »
In the aftermath of the explosion of BP’s Deepwater Horizon drilling rig in the Gulf of Mexico, a dispersed oil plume was formed at a depth between 3,600 and 4,000 feet and extending some 10 miles out from the wellhead. An intensive study by scientists with the Lawrence Berkeley National Laboratory (Berkeley Lab) found that microbial activity, spearheaded by a new and unclassified species, degrades oil much faster than anticipated. This degradation appears to take place without a significant level of oxygen depletion.
