Sunday, September 7, 2008

Simple Actions to Reduce Global Warming


The future is not somewhere we are going. It is something we are creating. Every day we do things that make some futures more probable and others less likely.


Global warming already disrupts millions of lives daily in the forms of destructive weather patterns and loss of habitat. What is already happening is only the tip of the melting iceberg, for it is our children and grandchildren who may suffer most from the effects of global warming. Hundreds of millions of people may be exposed to famine, water shortages, extreme weather conditions and a 20 - 30% loss of animal and plant species if we don’t reduce the rate of global warming and reduce GHG emissions.This article outlines some ways that you can act to help prevent the Earth from warming further. While humankind has the ability to destroy the planet, we can also help protect and sustain it.
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Friday, September 5, 2008

Iran launch of Omid successful


Iran announced Sunday that it launched a satellite into space earlier in the day, the country’s first domestically made.

The satellite, Omid (hope), was launched Sunday by using Safir (ambassador) satellite-carrier rocket, the armed forces said in a statement, quoted by the official IRNA news agency.

The Omid Satellite which was successfully fired on the birth anniversary of the last Imam (prophet) of Shiites, Hazrat Mahdi (who is believed to reappear at the end of the world) illustrated the auspicious name of the Imam in the space, IRNA said.

According to Iran’s English-language Press TV satellite channel, the domestically manufactured Omid Satellite will pass over the country six times a day.

The launch of Safir rocket aimed to test remote sensing, satellite telemetry, and geographic information system (GIS) technology as well as remote and ground station data processing, Press TV said.

Another news agency Fars quoted government spokesman Gholam- Hossein Elham as saying that President Mahmoud Ahmadinejad was at the launch of the communications satellite from Iran’s space station.

In February, Iran said it has prepared for the satellite launch by sending a probe into space of a rocket on the mission.

Ahmadinejad announced in his press interview in Istanbul Friday that Iran would in near future launch its first domestic satellite to the space.

Iran, embroiled in a standoff with the West over its disputed nuclear ambitions, has pursued a space program for several years, according to media reports.

Source : http://www.chinadaily.com.cn/

Tuesday, September 2, 2008

Isro,India to launch Italian, Algerian satellites

India - Antrix Corp. Ltd, the commercial arm of India’s space agency, has won a pair of deals from Algeria and Italy to launch earth observation satellites next year on the polar satellite launch vehicle, or PSLV, its workhorse rocket. 

The contract awarded by the Algerian space agency to launch Alsat-2A, a 200kg remote sensing satellite, is the first won by Antrix from an African nation. The Algerian agency has the option to launch a second such satellite. For the Italian space agency Agenzia Spaziale Italiana, Antrix will launch a satellite named IMSAT, which will be the second Italian satellite to be boosted into space by the Indian Space Research Organisation, or ISRO, which in April 2007 launched Agile, a 352kg scientific satellite. 

The Algerian and Italian satellites, besides a 100kg satellite for Nanyang Technological University in Singapore, and Cubesat, a three-satellite package from the Netherlands, would ride piggyback on heavier Indian satellites, said K.R. Sridhara Murthi, managing director of Antrix. He didn’t disclose financial details.

Antrix is also in talks with space agencies of South Africa and Nigeria to carry out similar launches, Murthi said. “We are also looking at opportunities bigger than that—remote sensing satellites, where payloads (are) of 800kg or even higher.” 

ISRO offers the home-grown PSLV to carry satellites of up to 1,700kg into low-earth orbit at a cost that’s nearly 30% cheaper than that charged by firms such as International Launch Services, owned by Space Transport Inc. and two Russian organizations, Khrunichev State Research and Production Space Center and RSC Energia. Low-earth orbit is the region above earth between 200km and 2,000km, ideal to place earth observation or remote sensing satellites. 

India is still a fledgling competitor in the global satellite manufacturing and launch industry, which is expected to grow to $145 billion (Rs6.3 trillion) over 10 years to 2016, from $116 billion in the 10 years to 2006, according to Paris-based research firm Euroconsult.

“(ISRO’s) benchmark is with international specifications on quality, reliability and credibility of the systems. And then, you are also cost competitive,” said K. Kasturirangan, director of the National Institute of Advanced Studies, a think tank in Bangalore. “The opportunity is just growing.” 

Source : http://www.livemint.com/

Thursday, August 28, 2008

Cut greenhouse gases to save coral reefs: scientists



To keep coral reefs from being eaten away by increasingly acidic oceans, humans need to limit the amount of climate-warming greenhouse gases in the atmosphere, a panel of marine scientists said on Wednesday.


"The most logical and critical action to address the impacts of ocean acidification on coral reefs is to stabilize atmospheric carbon dioxide concentration," the scientists said in a document called the Honolulu Declaration, for release at a U.S. conference on coral reefs in Hawaii.

Ocean acidification is another threat to corals caused by global warming, along with rising sea levels, higher sea surface temperatures and coral bleaching, the scientists said.

Coral reefs are a "sentinel ecosystem," a sign that the environment is changing, said one of the experts, Billy Causey of the U.S. National Marine Sanctuary Program.

"Although ocean acidification is affecting the health of our oceans, the same thing -- increased carbon dioxide in the atmosphere -- is going to in fact be affecting terrestrial environments also," Causey said by telephone from Hawaii.

Coral reefs offer economic and environmental benefits to millions of people, including coastal protection from waves and storms and as sources of food, pharmaceuticals, jobs and revenue, the declaration said.

But corals are increasingly threatened by warming sea surface temperatures as well as ocean acidification.

Oceans are getting more acidic because they have been absorbing some 525 billion tons of the greenhouse gas carbon dioxide over the last two centuries, about one-third of all human-generated carbon dioxide for that period.

The carbon dioxide combines with sea water to form carbonic acid.

Marine researchers have long recognized acidification in deep ocean water far from land, but a study published this year in the journal Science found this same damaging phenomenon on the Pacific North American continental shelf from Mexico to Canada, and quite likely elsewhere around the globe.

The water became so corrosive that it started dissolving the shells and skeletons of starfish, clams and corals.

Stabilizing carbon dioxide emissions was the Honolulu Declaration's top long-term recommendation. The key short-term recommendation was to nurture coral reefs that seem to have natural resilience against acidification.

This could be adopted immediately by managers of protected marine areas, Causey said.

The Honolulu Declaration will be presented to the United Nations and to other global, regional and national forums.
source

Monday, August 25, 2008

Finding You on a Map


By far the easiest way to determine where you are on a map is to pull out your pocket GPS (global positioning system receiver) and have it give you your map coordinates. If, however, you are like a lot of people, you don’t want to shell out a few hundred bucks for a GPS and, unless you are in an area with very little topographic relief, you don’t need one. You can determine your position quite accurately on a topographic map by using your compass to triangulate between three points.


The first step in triangulation is to pick three topographic features that you can see and can identify on your map (mountains are ideal). Start with the first feature you have chosen and determine the bearing between you and it, as outlined above. Once you have determined its bearing, pencil in a line with the same bearing on your map that runs through the chosen feature (having a protractor would be useful).

Repeat this for the other two features, drawing lines for each. The point where the three lines intersect on the map is where you are. Depending on how accurate your sightings were and how accurately you drew your lines through the features, there will probably be a some error in your location. Be sure to double check the map and reconcile it with what you see. If the lines intersect in a valley and you are on a hill, the location is obviously off a bit on the map.
source
 

Wednesday, August 20, 2008

Map Projections and Distortions


What is a Map?

Once a reference datum has been determined the elevation of any point can be accurately determined, and it will correlate to the elevation of any point on the earth's surface that has the same elevation and is using the same datum. But…how do you accurately represent the X and Y coordinates of that point? This question leads to one of the fundamental problems of mapmaking…how do you represent all or part of an ellipsoid object on a flat piece of paper? The answer to this question is a bit complicated, but understanding it is fundamental to understanding what maps actually represent (this statement will become clearer shortly).
In order to represent the surface of the earth on a flat piece of paper, the map area is projected onto the paper. There are many different types of projections, each with its own strengths and weaknesses.

The simplest (and easiest to visualize) example of a projection is a planar projection. To understand this type of projection, imagine inserting a piece of paper through the earth along the equator. Now imagine that the earth is semi-transparent and you could shine a flashlight oriented along the (geographic) polar axis through the earth.

The resulting outline on the paper would be a map created using this type of projection (known as a transverse azimuthal or planar projection).

There are three main types of projections, based on the shape of the 'paper' onto which the earth is projected. The example above used an azimuthal (planar) piece of paper.


 

The other main types, illustrated to the right, are cylindrical and conical projections. These three types of projections can be further modified by the way the 'paper' is oriented when it is inserted into the earth.

In the example above, the plane was oriented along the equator, known as a transverse orientation (hence the 'transverse azimuthal' projection). Projections may also be equatorial (oriented perpendicular to the plane of the equator) or oblique (oriented at some angle that is neither parallel nor perpendicular to the plane of the equator.

Map Projection Distortions

Each of the different types of projections have strenghts and weaknesses. Knowledge of these different advantages and disadvantages for a particular map projection will often help in which map to choose for a particular project. The basic problem inherent in any type of map projection is that it will result in some distortion of the ‘ground truth’ of the area being mapped.


There are four basic characteristics of a map that are distorted to some degree, depending on the projection used. These characteristics include distance, direction, shape, and area. The only place on a map where there is no distortion is along the trace of the line that marks the intersection of our ‘paper’ with the surface of the earth.

Any place on the map that does not lie along this line will suffer some distortion. Fortunately, depending on the type of projection used, at least one of the four characteristics can generally be preserved.
A conformal projection primarily preserves shape, an equidistant projection primarily preserves distance, and an equal-area projection primarily preserves area.


These image show the earth using different projections. Notice how the continents look stretched or squashed depending on the projection. Following are some websites with more information.

source


Sunday, August 17, 2008

Geoid

The geoid is that equipotential surface which would coincide exactly with the mean ocean surface of the Earth, if the oceans were in equilibrium, at rest, and extended through the continents (such as with very narrow canals). According to C.F. Gauss, who first described it, it is the “mathematical figure of the Earth,” a smooth but highly irregular surface that corresponds not to the actual surface of the Earth’s crust, but to a surface which can only be known through extensive gravitational measurements and calculations. Despite being an important concept for almost two hundred years in the history of geodesy and geophysics, it has only been defined to high precision in recent decades, for instance by works of P. Vaníček and others. It is often described as the true physical figure of the Earth, in contrast to the idealized geometrical figure of a reference ellipsoid.

Friday, August 15, 2008

Congratulations India


With all the inherent contradictions and weaknesses we Indians have an intense desire to succeed,to march ahead and to excel. This is our secret of suceess.Happy Independence Day to fellow Indians.