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Earth’s magnetic field has been weakening over the past six months

Changes measured by the Swarm satellite over the past 6 months shows that Earth’s magnetic field is changing. Shades of red show areas where it is strengthening, and shades of blue show areas that are weakening. Credit: ESA/DTU

“Earth’s magnetic field, which protects the planet from huge blasts of deadly solar radiation, has been weakening over the past six months, according to data collected by a European Space Agency (ESA) satellite array called Swarm.

The biggest weak spots in the magnetic field — which extends 370,000 miles (600,000 kilometers) above the planet’s surface — have sprung up over the Western Hemisphere, while the field has strengthened over areas like the southern Indian Ocean, according to the magnetometers onboard the Swarm satellites — three separate satellites floating in tandem.

The scientists who conducted the study are still unsure why the magnetic field is weakening, but one likely reason is that Earth’s magnetic poles are getting ready to flip, said Rune Floberghagen, the ESA’s Swarm mission manager. …”Such a flip is not instantaneous, but would take many hundred if not a few thousand years,” Floberghagen told Live Science. “They have happened many times in the past.””

July 8, 2014
http://www.livescience.com/46694-magnetic-field-weakens.html

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Climate Change Worse Than We Thought, Likely To Be ‘Catastrophic Rather Than Simply Dangerous’

“Climate change may be far worse than scientists thought, causing global temperatures to rise by at least 4 degrees Celsius by 2100, or about 7.2 degrees Fahrenheit, according to a new study.

The study, published in the journal Nature, takes a fresh look at clouds’ effect on the planet, according to a report by The Guardian. The research found that as the planet heats, fewer sunlight-reflecting clouds form, causing temperatures to rise further in an upward spiral.

That number is double what many governments agree is the threshold for dangerous warming. Aside from dramatic environmental shifts like melting sea ice, many of the ills of the modern world — starvation, poverty, war and disease — are likely to get worse as the planet warms.

“4C would likely be catastrophic rather than simply dangerous,” lead researcher Steven Sherwood told the Guardian. “For example, it would make life difficult, if not impossible, in much of the tropics, and would guarantee the eventual melting of the Greenland ice sheet and some of the Antarctic ice sheet.”

Another report released earlier this month said the abrupt changes caused by rapid warming should be cause for concern, as many of climate change’s biggest threats are those we aren’t ready for.”

http://www.huffingtonpost.com/2013/12/31/climate-change-worse_n_4523828.html

Earth’s poles are shifting because of climate change

“Climate change is causing the North Pole’s location to drift, owing to subtle changes in Earth’s rotation that result from the melting of glaciers and ice sheets.

Computer simulations had suggested that the melting of ice sheets and the consequent rise in sea level could affect the distribution of mass on the Earth’s surface. This would in turn cause the Earth’s axis to shift, an effect that has been confirmed by measurements of the positions of the poles.

Jianli Chen of the University of Texas at Austin and colleagues have shown that melting due to our greenhouse-gas emissions is making its own contribution to the shift. …”Ice melting and sea level change can explain 90 per cent of the [eastward shift],” says Chen. “The driving force for the sudden change is climate change.””

http://www.newscientist.com/article/dn24755-earths-poles-are-shifting-because-of-climate-change.html

The crisis of civilisation is an unprecedented opportunity

“… while the crisis of civilisation shows that business-as-usual is not sustainable – and could at worst lead to an uninhabitable planet by the end of this century based on the consensus science projections – we are already in the midst of a process of civilisational transition which offers unprecedented opportunities to re-envision new forms of prosperity that can function in harmony with our environment, rather than in conflict with it.”

http://www.theguardian.com/environment/earth-insight/2013/sep/24/crisis-civilisation-unprecedented-opportunity-transition

The End of the Holocene

“…a group of researchers from Harvard and Oregon State University has published the first global temperature reconstruction for the last 11,000 years – that’s the whole Holocene (Marcott et al. 2013). The results are striking… 

Over the last decades, numerous researchers have painstakingly collected, analyzed, dated, and calibrated many data series that allow us to reconstruct climate before the age of direct measurements. Such data come e.g. from sediment drilling in the deep sea, from corals, ice cores and other sources. Shaun Marcott and colleagues for the first time assembled 73 such data sets from around the world into a global temperature reconstruction for the Holocene, published in Science. Or strictly speaking, many such reconstructions: they have tried about twenty different averaging methods and also carried out 1,000 Monte Carlo simulations with random errors added to the dating of the individual data series to demonstrate the robustness of their results.

To show the main result straight away, it looks like this:


Figure 1 Blue curve: Global temperature reconstruction from proxy data of Marcott et al, Science 2013. Shown here is the RegEM version – significant differences between the variants with different averaging methods arise only towards the end, where the number of proxy series decreases. This does not matter since the recent temperature evolution is well known from instrumental measurements, shown in red (global temperature from the instrumental HadCRU data). Graph: Klaus Bitterman.

The climate curve looks like a “hump”. At the beginning of the Holocene – after the end of the last Ice Age – global temperature increased, and subsequently it decreased again by 0.7 ° C over the past 5000 years. The well-known transition from the relatively warm Medieval into the “little ice age” turns out to be part of a much longer-term cooling, which ended abruptly with the rapid warming of the 20th Century. Within a hundred years, the cooling of the previous 5000 years was undone.”

Read more: http://www.realclimate.org/index.php/archives/2013/09/paleoclimate-the-end-of-the-holocene/

Control a rat with your brain

“Harvard scientists create an interface that allows humans to move a rat’s tail just by thinking about it.

We’re not quite at the stage where we can communicate brain to brain with our fellow humans, but we may be on our way to communicating with other species. Or at least controlling them, thanks to a new, non-invasive interface developed by scientists at Harvard Medical School.

A team led by Seung-Schik Yoo, an assistant professor of radiology, has created a brain-to-brain interface (BBI) that allows a human controller to move a portion of a rat’s body just by thinking about it, all without invasive surgical implants.

…Using six different human subjects and six different rat subjects, the team achieved a success rate of 94 percent, with a time delay of 1.59 ± 1.07 seconds between user intention and the rat’s response.”

http://news.cnet.com/8301-17938_105-57596633-1/control-a-rat-with-your-brain/

New high-tech laser method allows DNA to be inserted ‘gently’ into living cells

“A team of scientists in South Korea have now developed the most precise method ever used to insert DNA into cells. The method combines two high-tech laboratory techniques and allows the researchers to precisely poke holes on the surface of a single cell with a high-powered “femtosecond” laser and then gently tug a piece of DNA through it using “optical tweezers,” which draw on the electromagnetic field of another laser. The team’s approach, which is a breakthrough in precision and control at the single-cell level, was published today in the Optical Society’s (OSA) open-access journal Biomedical Optics Express.”

http://www.eurekalert.org/pub_releases/2013-08/tos-nhl080713.php

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