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Another underestimated source of CO2, are turbulent waters. "The stronger the turbulences at the water's surface, the more CO2 is released into the atmosphere. The combination of maps and data revealed that, while the CO2 emissions from lakes and reservoirs are lower than assumed, those from rivers and streams are three times as high as previously believed." Alltogether the emitted CO2 equates to roughly one-fifth of the emissions caused by humans. Yet more stuff to model...

Nasia, I thought about your statement carefully - and I cannot agree with you. Water is not a greenhouse gas. It is instead a liquid. Also, I can't believe you keep feeding the troll! :-P But on a more topical note: I think it is an over-simplification to call water a greenhouse gas - water is one of the most important mechanisms in the way Earth handles heat input from the sun. The latent heat that you mention actually cools Earth: solar energy that would otherwise heat Earth's surface is ABSORBED as latent heat by water which consequently evaporates - the same water condenses into rain drops at high altitudes and releases this stored heat. In effect the water cycle is a mechanism of heat transport from low altitude to high altitude where the chance of infrared radiation escaping into space is much higher due to the much thinner layer of atmosphere above (including the smaller abundance of greenhouse gasses). Also, as I know you are well aware, the cloud cover that results from water condensation in the troposphere dramatically increases albedo which has a cooling effect on climate. Furthermore the heat capacity of wet air ("humid heat") is much larger than that of dry air - so any advective heat transfer due to air currents is more efficient in wet air - transporting heat from warm areas to a natural heat sink e.g. polar regions. Of course there are also climate heating effects of water like the absorption of IR radiation. But I stand by my statement (as defended in the above) that rain cools the atmosphere. Oh and also some nice reading material on the complexities related to climate feedback due to sea surface temperature: http://journals.ametsoc.org/doi/abs/10.1175/1520-0442(1993)006%3C2049%3ALSEOTR%3E2.0.CO%3B2

I enjoy trolling conversations when there is a gain for both sides at the end :-) . I had to check upon some of the facts in order to explain my self properly. The IPCC report states the greenhouse gases here, and water vapour is included: http://www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-2-1.html Honestly, I read only the abstract of the article you posted, which is a very interesting hypothesis on the mechanism of regulating sea surface temperature, but it is very localized to the tropics (vivid convection, storms) a region of which I have very little expertise, and is difficult to study because it has non-hydrostatic dynamics. The only thing I can comment there is that the authors define constant relative humidity for the bottom layer, supplied by the oceanic surface, which limits the implementation of the concept on other earth regions. Also, we may confuse during the conversation the greenhouse gas with the Radiative Forcing of each greenhouse gas: I see your point of the latent heat trapped in the water vapour, and I agree, but the effect of the water is that it traps even as latent heat an amount of LR that would otherwise escape back to space. That is the greenhouse gas identity and an image to see the absorption bands in the atmosphere and how important the water is, without vain authority-based arguments that miss the explanation in the end: http://www.google.nl/imgres?imgurl=http://www.solarchords.com/uploaded/82/87-33833-450015_44absorbspec.gif&imgrefurl=http://www.solarchords.com/agw-science/4/greenhouse--1-radiation/33784/&h=468&w=458&sz=28&tbnid=x2NtfKh5OPM7lM:&tbnh=98&tbnw=96&zoom=1&usg=__KldteWbV19nVPbbsC4jsOgzCK6E=&docid=cMRZ9f22jbtYPM&sa=X&ei=SwynUq2TMqiS0QXVq4C4Aw&ved=0CDkQ9QEwAw

safe not only fossil fuels when biking but clean the air at the same time :-) (well... in theory)

Global air travel contributes around 3.5 percent of the greenhouse gas emissions behind/driving anthropogenic climate change, according to the International Panel on Climate Change (IPCC). But what impact does a warming planet have on air travel and how might that, in turn, affect the rate of warming itself?

well it depends on how the air is compressed,but if clean electricity is used for it is kind of interesting

f existing lithium-ion batteries were scaled up to match the range capacity of gas-powered vehicles, they would be unfeasibly large and heavy. Lithium-air batteries, which have the potential to provide energy densities that rivals traditional gasoline-powered engines, are seen as a possible solution.

one more, France will have one officially by July, so who's next?

500000 lego bricks, a tank of compressed air, some mechanical engineering and a lot of time later...

not for space but the air breathing battery still is a nice concept - would make robots more "human" if they have to breath :-)

Asimov's Foundation meets ACT's Tipping Point Prediction?

still, some interesting thoughts in there ... "Then you have the 50-year cycles of violence. Turchin describes these as the building up and then the release of pressure. Each time, social inequality creeps up over the decades, then reaches a breaking point. Reforms are made, but over time, those reforms are reversed, leading back to a state of increasing social inequality. The graph above shows how regular these spikes are - though there's one missing in the early 19th century, which Turchin attributes to the relative prosperity that characterized the time. He also notes that the severity of the spikes can vary depending on how governments respond to the problem. Turchin says that the United States was in a pre-revolutionary state in the 1910s, but there was a steep drop-off in violence after the 1920s because of the progressive era. The governing class made decisions to reign in corporations and allowed workers to air grievances. These policies reduced the pressure, he says, and prevented revolution. The United Kingdom was also able to avoid revolution through reforms in the 19th century, according to Turchin. But the most common way for these things to resolve themselves is through violence. Turchin takes pains to emphasize that the cycles are not the result of iron-clad rules of history, but of feedback loops - just like in ecology. "In a predator-prey cycle, such as mice and weasels or hares and lynx, the reason why populations go through periodic booms and busts has nothing to do with any external clocks," he writes. "As mice become abundant, weasels breed like crazy and multiply. Then they eat down most of the mice and starve to death themselves, at which point the few surviving mice begin breeding like crazy and the cycle repeats." There are competing theories as well. A group of researchers at the New England Complex Systems Institute - who practice a discipline called econophysics - have built their own model of political violence and

It's not the scientific activity described in the article that is uninteresting, on the contrary! But the way it is described is just a bad joke. Once again the results itself are seemingly not sexy enough and thus something is sold as the big revolution, though it's just the application of the oldest scientific principles in a slightly different way than used before.

A very interesting (although complicated and time-consuming) way of fetching items.

First experimental study of laser filamentation in the mid-IR.

Nanometre-sized rods of carbon can expel water in puffs of vapour when the air is already humid. Materials such as carbon and silica gels typically pick up moisture as humidity increases. But Satish Nune and his colleagues at the Pacific Northwest National Laboratory in Richland, Washington, found that their carbon-based nanorods take up water at low humidity and then give off about half of it when the relative humidity exceeds 50-80%. The team thinks that water condenses between adjacent rods and then capillary forces draw the rods together until the water bursts from the ends of the rods and evaporates.

I hate scorpions, but this could be a nice subject for a future Ariadna study! This north African desert scorpion, doesn't dig burrows to protect itself from the sand-laden wind (as the other scorpions do). When the sand whips by at speeds that would strip paint away from steel, the scorpion is able to scurry off without apparent damage.

Nice research, though they have done almost all the work that we could do in an Ariadna, didnt they? "To check, they took further photographs. In particular, they used a laser scanning system to make a three-dimensional map of the armour and then plugged the result into a computer program that blasted the virtual armour with virtual sand grains at various angles of attack. This process revealed that the granules were disturbing the air flow near the skeleton's surface in ways that appeared to be reducing the erosion rate. Their model suggested that if scorpion exoskeletons were smooth, they would experience almost twice the erosion rate that they actually do. Having tried things out in a computer, the team then tried them for real. They placed samples of steel in a wind tunnel and fired grains of sand at them using compressed air. One piece of steel was smooth, but the others had grooves of different heights, widths and separations, inspired by scorpion exoskeleton, etched onto their surfaces. Each sample was exposed to the lab-generated sandstorm for five minutes and then weighed to find out how badly it had been eroded. The upshot was that the pattern most resembling scorpion armour-with grooves that were 2mm apart, 5mm wide and 4mm high-proved best able to withstand the assault. Though not as good as the computer model suggested real scorpion geometry is, such grooving nevertheless cut erosion by a fifth, compared with a smooth steel surface. The lesson for aircraft makers, Dr Han suggests, is that a little surface irregularity might help to prolong the active lives of planes and helicopters, as well as those of scorpions."

What bugs me (pardon the pun) is that the dimensions of the pattern they used were scaled up by many orders of magnitude, while "grains of sand" with which the surface was bombarded apparently were not... Not being a specialist in the field, I would nevertheless expect that the size of the surface pattern *in relation to* to size of particles used for bombarding would be crucial.

Researchers in the US have made a "carpet cloak" that makes objects invisible to sound waves. The device is the first such cloak to work in air and could be used to improve the acoustics in concert halls or even to control unwanted noise.

Find yourself in an area without breathable air? No problem... just use this!

Aerographite. This post was originally published on Mashable. German scientists have developed a sturdy material called Aerographite made mostly of air, opening up huge implications for the future development of electronics. The jet-black, non-transparent porous carbon material - which was created by scientists at Kiel University and Hamburg University of Technology - was detailed in the July edition of scientific journal Advanced Materials .

Why print stuff if you can turn it into an amazing air hockey table! Note, you will probably keep losing...

The battery is based on a liquid electrolyte that uses oxygen from the surrounding air to produce a high battery capacity (up to 27kWh per liter). Needless to say, this type requires an atmosphere to operate and who knows what environmental impacts may be

When submerged, water tends to cling to the top of the spikes, while air and water vapor accrue in the pores between them. The combination of trapped air and water vapor within these cavities forms a gaseous layer that deters moisture from seeping into the surface below. More materials with amazing properties. Might even be usefull for liquid fuel tanks?

I don't quite see how the trapped water vapor keeps the water out of the cavities... since the vapor is at the same low temperature as the water it should hardly exert any pressure at all. One would expect though that surface tension keeps water out of smaller cavities because it tries to minimize surface area. If the water would enter the cavities it would need increase its surface area dramatically which in turn is energetically unfavorable. Interesting application would also be in non-wetting electronics which might make cooling of circuitry a lot easier: you just sink your data center.

Seems looking into turbulence is a source of innovative concepts. After the black hole modelling here was found a mathematical expression which describes "how turbulence can alter the shape and course of a flock of birds, a swarm of insects or even an algal bloom (phytoplankton!) and could help us to better predict them". More relevant for motions in air and sea, rather than space, where the fluids are dense enough to exhibit turbulence ; but what about a swarm moving in and exploring an exoplanet's atmosphere?