Nature News: Two lines of evidence nearly brought down the last-minute climate agreement brokered last week in Copenhagen by US President Barack Obama: studies indicating that the impacts of global warming could be more severe than previously thought, and that rich countries could do more to counter the problem without breaking the bank.
Now, negotiators are seeing whether they can strengthen a deal nearly universally acknowledged as weak — or whether even the mounting scientific evidence on the most dire effects of climate change will be enough to forge a more meaningful deal.
Monthly Archives: December 2009
Strength of titanium parts on Mars probe questioned
SPACE.com: The trouble-plagued, delayed, and cost-overrun Mars Science Laboratory mission is crawling out of the technical and financial doghouse.
Still, there’s one issue that could keep the roughly $2.3 billion NASA mission grounded: titanium parts that may not be strong enough for the robotic rover.
CERN’s CLOUD experiment
Physics Today: CLOUD (cosmics leaving outdoor droplets) is a novel experiment at CERN to investigate the possible influence of galactic cosmic rays on Earth’s clouds and climate by studying the microphysical interactions.
Using the 50-year-old proton synchrotron, researchers simulate cosmic rays passing through Earth’s atmosphere, in hopes of revealing the extent to which the constant background drizzle of charged particles affects cloud formation.
Earlier experiments have suggested that ionization causes clouds to “seed” and that ionization is influenced by the type and quantity of cosmic rays that reaching Earth.
CLOUD has been running since 2006 and proved that cosmic rays bombarding Earth’s atmosphere may have an influence on the amount of cloud cover through the formation of new aerosols (tiny particles suspended in the air that seed cloud droplets).
This result is supported by satellite measurements, which show a possible correlation between cosmic-ray intensity and the amount of low cloud cover. Clouds exert a strong influence on Earth’s energy balance; changes of only a few percent have an important effect on the climate. Understanding the microphysics in controlled laboratory conditions is a key to unravelling the connection between cosmic rays and clouds.
The experiment
The initial stage of the experiment uses a prototype detector in a particle beam. CLOUD uses CERN’s Proton Synchrotron to send a beam of particles – the ‘cosmic rays’ – into a reaction chamber. The effect of the beam on aerosol production will be recorded and analyzed.
The roots of the experiment can be traced as far back as two centuries, to the time when the astronomer royal, William Herschel, noticed a correlation between sunspots and the price of wheat in England. Herschel’s observation was the first to suggest that solar variation may affect Earth’s climate. Solar-climate variability has remained a great puzzle since that time, despite an intensive scientific efforts.
During the ‘Little Ice Age’ around the 17th and 18th centuries, when sunspots all but disappeared for 70 years, the cosmic ray intensity increased and the climate cooled. Apparently that was merely the latest of around a dozen similar events over the past 10 000 years. At present, there is no established reason for the Sun’s brightness to fluctuate on these time scales. The possibility that galactic cosmic rays, which are modulated by changes of the solar wind, may directly influence the climate is therefore attracting the interest of scientists.
The CLOUD collaboration brings together atmospheric physicists, solar physicists, and cosmic-ray and particle physicists to address a key question in the understanding of clouds and climate change. “CERN is a unique environment for this experiment,” says CLOUD spokesperson Jasper Kirkby of CERN.
The first beam data from the full CLOUD experiment is expected in 2010.
Clouds are one of the primary factors in determining global surface temperature, but the United Nation’s Intergovernment Panel on Climate Change admits that current level of scientific understanding of them is limited.
The first functional molecular transistor
Wired.com: Researchers have showed the first functional transistor made from a single molecule. The transistor, which has a benzene molecule attached to gold contacts, could behave just like a silicon transistor.
The molecule’s different energy states can be manipulated by varying the voltage applied to it through the contacts. And by manipulating the energy states, researchers were able to control the current passing through it.
What’s wrong with this snowflake?
NPR: During the holiday season we see images of lots of geometrically incorrect snowflakes.
Chemist Thomas Koop thinks ice crystals are masterpieces of natural beauty. Unfortunately, he says, “This beauty is sometimes corrupted.”
Koop, a professor at Bielefeld University in Germany, says the problem is that many of these images show ice crystals with five or eight sides. In other words, he says, they are scientific abominations.
Related news story
Christmas card snowflakes ‘corrupt nature’ by defying laws of physics
Climate change in the US
washingtonpost.com: Manmade climate change could bring parching droughts to the Southwest and pounding rainstorms to Washington, put Vermont maple sugar farms out of business and Key West underwater over the next century, according to a federal report released during the summer.
The report, a compilation of work by government scientific agencies, provided the most detailed picture yet of the United States in 2100, if nothing is done to cut greenhouse gas emissions. It found that a warmer world, with average US temperatures increasing four to 11 degrees, would significantly alter natural ecosystems and urban life.
ESA approves collaborative Mars program with NASA
SPACE.com: European Space Agency (ESA) governments have finally approved to a two-part Mars exploration program to be conducted with NASA and have confirmed their commitment to spend 850 million euros ($1.23 billion) on missions in 2016 and 2018.
How aircraft emissions contribute to warming
Nature News: The first analysis of emissions from commercial airline flights shows that they are responsible for 4–8% of surface global warming since surface air temperature records began in 1850—equivalent to a temperature increase of 0.03–0.06 °C overall.
The analysis, by atmospheric scientists at Stanford University in Palo Alto, California, also shows that in the Arctic, aircraft vapor trails produced 15–20% of warming.
A conversation with Frank A. Wilczek
NYTimes.com: He is good-natured, funny, and thought to be among the smartest men in physics: Frank A. Wilczek, 58, a professor at the Massachusetts Institute of Technology, was one of three winners of the 2004 Nobel Prize in Physics and is a frequent columnist for Physics Today.
The award came for work Wilczek had done in his 20s, with David Gross of Princeton University, on quantum chromodynamics, a theoretical advance that is part of the foundation of modern physics.
The New York Times provides an edited version of two conversations with Wilczek, in October and this month.
Why the ‘golden ratio’ pleases the eye
guardian.co.uk: From Leonardo da Vinci to Le Corbusier, the golden ratio is believed to have guided artists and architects over the centuries.
Leonardo is thought to have used the golden ratio, a geometric proportion regarded as the key to creating aesthetically pleasing art, when painting the Mona Lisa.
Now a US academic believes he has discovered the reason why it pleases the eye.
According to Adrian Bejan, professor of mechanical engineering at Duke University in Durham, North Carolina, the human eye is capable of interpreting an image featuring the golden ratio faster than any other.