A study from Norwegian and Newzealand scientists provides updated number of carbon dioxide emissions from fossil fuels. While the global financial crisis may have slowed down the emission growth, it has not been sufficient enough to stop it. From 2007 to 2008 global emissions from fossil fuels increased by 2.2 %. From 2003 to 2007, the average fossil emissions increased by
3.7 % a year.
According to study published in Environment Research Letters, coal in 2006 has bypassed oil as the largest source of carbon dioxide emissions. Emissions from gas and oil have had a rather constant growth since 1990. Coal is now the driver of the strong fossil fuel Carbon dioxide emission growth.
The growth rate of emissions has been a slightly higher in India the last two years. For the first time India's emissions now increase faster than the Chinese emissions.
According to the International Panel on Climate Change (IPCC), a large reduction of fossil emissions is required to reduce global warming. The concentration of CO2 in atmosphere has been increased from 280 ppm in 1750 to 383 ppm in 2007. Around 75 % of the increase until now is due to carbon dioxide emissions from fossil energy. 25 % is due to changes in land use.
All main IPCC scenarios of fossil fuel Carbon dioxide emissions show an increase over the next few decades with a large spread in emissions estimates upto 2100. And this increasing trend is driven by enhanced economic growth.
Sunday, November 22, 2009
Tuesday, November 17, 2009
'Doomsday' 2012 Prediction Explained
According to Ann Martin, a doctoral candidate in Cornell University's Department of Astronomy, the world will NOT end on December 21, 2012, contrary to what the latest Hollywood Blockbuster movie suggests. Her research focuses on the hydrogen contents of galaxies in the nearby universe.
She says that the Mayan calendar was designed to be cyclical, so the fact that the world will come to an end in December 2012 is really of no consequence. Simply, it is the end of great calendar cycle in Mayan society. It does not mean that the "world will end", she says.
For the past three years, Martin has been a volunteer with Cornell's "Curious? Ask an Astronomer" service, a website founded by Astronomy Graduate Students in 1997. This website features the answers to over 750 FAQ's regarding the field of astronomy.
For further information see:
http://curious.astro.cornell.edu/question.php?number=686
She says that the Mayan calendar was designed to be cyclical, so the fact that the world will come to an end in December 2012 is really of no consequence. Simply, it is the end of great calendar cycle in Mayan society. It does not mean that the "world will end", she says.
For the past three years, Martin has been a volunteer with Cornell's "Curious? Ask an Astronomer" service, a website founded by Astronomy Graduate Students in 1997. This website features the answers to over 750 FAQ's regarding the field of astronomy.
For further information see:
http://curious.astro.cornell.edu/question.php?number=686
Sunday, November 1, 2009
New DNA Method Makes It Easier To Trace Criminals
DNA samples often convict criminals. But many of today's forensic tests are so polluted by soil, tobacco and food remains, for example, that they can not be used. Now researchers at Lund University in Sweden, working together with the Swedish National Laboratory of Forensic Science, SKL, have improved a critical part of the analysis process.
The first findings, published in the latest issue of the journal Biotechniques, indicate that the new method strengthens the DNA analysis so that previously negative samples yield positive and usable DNA profiles.
"The results are overwhelming. In my study I selected 32 truly difficult samples from the SKL archive, that is, with few cells, little DNA, and many so-called inhibitors, meaning lots of junk. With current methods it was impossible to get acceptable DNA profiles from any of them. But with the new method, 28 of the samples yielded more usable DNA profiles," says Johannes Hedman, an industrial doctoral candidate from SKL doing research at the Faculty of Engineering, Lund University.
Genetic information has become more and more common in forensic analyses. The analysis flow usually starts with taking a sample with a swab from a drinking glass or a blood spot, for example. The cells from the swab are then dissolved in water, and the DNA is extracted.
In forensics all over the world, much work has been done to improve the taking and handling of samples.
"The DNA analysis, on the other hand, has been something of a black box, since it is purchased as a finished product. No one has tried to improve it to be able to deal with dirty samples. But this is absolutely crucial, since the samples often have extremely small amounts of DNA. In this phase you copy certain parts of the DNA strands and then obtain a DNA profile that is unique to each person.
In the copying step, I have optimized the chemical environment and replaced a key enzyme, a so-called DNA polymerase. This yields a clearer genetic footprint, a DNA profile, to work with," explains Johannes Hedman. He has also devised a new mathematical model that makes it easy to interpret the DNA analysis.
If the copying phase is improved, stronger DNA evidence can be shown from crime scenes that today provide only partial or entirely blank DNA profiles. In other words, the chances are greater that a person can be found and linked to a particular crime.
The reason Johannes Hedman wound up at Lund is the fact that Peter Rådström, a professor of microbiological engineering, has been working since the late 1980s to improve DNA-based infection diagnostics and microbiological analyses for food. SKL was eager to find out whether these research findings could be applied to improving forensic DNA analysis.
"This collaboration opens new vistas for both SKL and Lund University, and we hope to be able to continue to work together with Peter Rådström's team. We have truly seen cross-fertilization," says Birgitta Rasmusson, research director at SKL.
The first findings, published in the latest issue of the journal Biotechniques, indicate that the new method strengthens the DNA analysis so that previously negative samples yield positive and usable DNA profiles.
"The results are overwhelming. In my study I selected 32 truly difficult samples from the SKL archive, that is, with few cells, little DNA, and many so-called inhibitors, meaning lots of junk. With current methods it was impossible to get acceptable DNA profiles from any of them. But with the new method, 28 of the samples yielded more usable DNA profiles," says Johannes Hedman, an industrial doctoral candidate from SKL doing research at the Faculty of Engineering, Lund University.
Genetic information has become more and more common in forensic analyses. The analysis flow usually starts with taking a sample with a swab from a drinking glass or a blood spot, for example. The cells from the swab are then dissolved in water, and the DNA is extracted.
In forensics all over the world, much work has been done to improve the taking and handling of samples.
"The DNA analysis, on the other hand, has been something of a black box, since it is purchased as a finished product. No one has tried to improve it to be able to deal with dirty samples. But this is absolutely crucial, since the samples often have extremely small amounts of DNA. In this phase you copy certain parts of the DNA strands and then obtain a DNA profile that is unique to each person.
In the copying step, I have optimized the chemical environment and replaced a key enzyme, a so-called DNA polymerase. This yields a clearer genetic footprint, a DNA profile, to work with," explains Johannes Hedman. He has also devised a new mathematical model that makes it easy to interpret the DNA analysis.
If the copying phase is improved, stronger DNA evidence can be shown from crime scenes that today provide only partial or entirely blank DNA profiles. In other words, the chances are greater that a person can be found and linked to a particular crime.
The reason Johannes Hedman wound up at Lund is the fact that Peter Rådström, a professor of microbiological engineering, has been working since the late 1980s to improve DNA-based infection diagnostics and microbiological analyses for food. SKL was eager to find out whether these research findings could be applied to improving forensic DNA analysis.
"This collaboration opens new vistas for both SKL and Lund University, and we hope to be able to continue to work together with Peter Rådström's team. We have truly seen cross-fertilization," says Birgitta Rasmusson, research director at SKL.
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