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Meet the incredible shrinking material. Most things swell when they warm up, creating engineering headaches, but now a 3D-printed material has been configured to contract instead. When two interlinked materials expand at different rates, they can warp or crack. It's a problem in buildings, bridges, electronics and anything else that is exposed to a wide temperature swing.

Following a discussion with Kzrystof, where he came up with gravity anomaly reasons for why Dutch people are so tall. Funny to see this fact gathers scientific attention as well.

We solved this darwinian riddle years ago. They must be tall in order to find their partners above the fog and thus reproduce in the dutch weather.

Filaments of plasma created by a high-powered laser beam undergo a similar type of phase transition as liquid percolating through a porous material - that is the conclusion of physicists in Switzerland. The also describe the application of laser filamentation for directed lightening and encouraged rainfall - Isabelle should come back to take a closer look :p

Christophe? Isabelle?

Some bacteria can influence the weather. Up high in the sky where clouds form, water droplets condense and ice crystal grow around tiny particles. Typically these particles are dust, pollen, or even soot from a wildfire. But recently scientists have begun to realize that some of these little particles are alive - they are bacteria evolved to create ice or water droplets around themselves. old but might be worth a discussion

The novel part here is that it can be scaled down to the cubesat platform. I then wondered, could we place multiple of such Cubesats in a 'decaying orbit' around the Sun? Fractionated will give spatial and temporal information which, even with a simple langmuir probe setup, can give information on density, temperature, velocity, ion energy distribution, potential.. Of course they will be lost relatively quickly, but more could be ejected from a mother ship which is orbiting at a safer distance.

For example like the KickSat projec https://www.kickstarter.com/projects/zacinaction/kicksat-your-personal-spacecraft-in-space Although a pc-reboot due to a radiation event in the electronics has reset the deployment timeline to approximately 2 days after re-entry... http://www.huffingtonpost.co.uk/2014/05/06/kicksat-satellites_n_5273821.html

Problem solved.

Those would also work very well to keep the Kaiju's out..

Good point!

Very comprehensive thanks to the narrator from EUMETSAT training office (plus aesthetically pleasing)

S. Hawking argues black holes might not exist: "The absence of event horizons mean that there are no black holes - in the sense of regimes from which light can't escape to infinity." Physicists will likely appreciate...

A visualization of global weather conditions forecast by supercomputers updated every three hours.

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

Is this correct? The conclusions indicate that contrary to what felt extreme weather events are not increasing?? Where is the trick?

The secret is in the details: http://en.wikipedia.org/wiki/Global_Warming_Policy_Foundation#Funding_Sources

don't get fooled, this is the same strategy employed successfully by the tabac industry: installing doubt - all under the cover of science of course and using its methods; remember all these publications showing the overall beneficial effects of smoking, the "un-clear" link to lung cancer etc ... same here

so it took us 70% of the time Earth is in the habitable zone to develop, would this be normal or could it be much faster? In other words, would all forms of life that started on a planet that originated at a 'similar' point in time like us, be equally far developed?

That is actually quite tricky to estimate rly. If for no other reason than the fact that all of the mass extinctions we had over the Earth's history basically reset the evolutionary clock. Assuming 2 Earths identical in every way but one did not have the dinosaur wipe-out impact, that would've given non-impact Earth 60million years to evolve a potential dinosaur intelligent super race.

The opposite might be true - or might not be ;-). Since usually the rate of evolution increases after major extinction events the chance is higher to produce 'intelligent' organisms if these events happen quite frequently. Usually the time of rapid evolution is only a few million years - so Earth is going quite slow. Certainly extinction events don't reset the evolutionary clock - if they would never have happened Earth gene pool would probably be quite primitive. By the way: dinosaurs were a quite diverse group and large dinosaurs might well have had cognitive abilities that come close to whales or primates - the difference to us might be that we have hands to manipulate our environment and vocal cords to communicate in very diverse ways. Modern dinosaur (descendents), i.e. birds, contain some very intelligent species - especially with respect to their body size and weight.

Mosaik Time Lapse video of the San Francisco Sky taken over one year.

Awesome video... music is freaking me out a bit though

The next advance in weather forecasting may not come from a new satellite or supercomputer, but from a device in your pocket. University of Washington atmospheric scientists are using pressure sensors included in the newest smartphones to develop better weather forecasting techniques.

The redbull mission will attempt to transcend human limits. Supported by a team of experts Felix Baumgartner plans to ascend to 120,000 feet in a stratospheric balloon and make a freefall jump rushing toward earth at supersonic speeds before parachuting to the ground.

since months austria is not speaking about anything else ... hope it is over soon :-) seriously: they even had last year Armstrong coming over to discuss with this guy on television (have posted it here) and the whole Red Bull advertisement machinery is working full speed on this ... quite impressive for just a jump ...

The International Space Apps Challenge is now over, it is interesting to have a look at the solutions ...

what sort of "app" is this e.g. http://spaceappschallenge.org/challenge/brightest-night/solution/132 "We started of by trying to set our camera in raw mode, howsoever this can't be done for current logitech modules and without a high risk of permanently destroying the camera (reflashing the EEPROM). we use a logitech c920 and captured a raw image from it using guvcview on ArchLinux we then wrote some python code to calculate the average BGR value of our Image. We are currently workin on automiztion, but this will take much longer as there will be a lot of reverse engineering of the USB-Protocol needed."

c'mon really! To name a few: - Tour of the Solar System ... that is one of the numerous specialities of the ACT. - Satellite data correlation tool ... solution is flawed, but I really like the idea. Lot of added value. I definitely think are interestung stuffs to do there for cheap. - Aurora project: Model & Data ... space weather not interesting?! - Kepler ... a classic Do not expect the solutions to be tremendous just after 3 days of work, but the proposed list of challenges are "seeds" for innovation to me.

Using a sophisticated weather model, environmental engineers at Stanford have defined optimal placement of a grid of four wind farms off the U.S. East Coast. The model successfully balances production at times of peak demand and significantly reduces costly spikes and zero-power events.

Altering local weather?

for Tobi! nice analogy between the threat and the fast responding in human network

Yet another example of "because scientifically accurate title would sound sooo boring".