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What stroke me especially was the shape of the Marianas Trench (much wider than deep) [edit] This reminds me I used to have a printout of a similar, but more space-related, comic http://xkcd.com/482/ hanging on the wall next to my desk in estec... good ol' times...

and in case you missed it, check also the excellent Money infographic that guy created last year: http://xkcd.com/980/huge/

exciting news ... especially now that apparently Obama proposes to cut the mars exploration programme ...

A worrying future looms as scientist predict the iconic great barrier reef is at a turning point and could experience irreversible damage before 2030 if nothing is done right now. Well actually, I am not sure if anything can be done as the two degree rise (and changes in ocean temperature/acidity probably?) will likely happen in any case due to delayed effects of decades of pollution, whether or not we stop now with emissions will probably not make much difference. :(

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

nice indeed! " Triggered by commonly available ambient mechanical energy such as human footfalls, a NG with size smaller than a human palm can generate maximum short-circuit current of 2 mA, delivering instantaneous power output of 1.2 W to external load. The power output corresponds to an area power density of 313 W/m2 and a volume power density of 54 268 W/m3 at an open-circuit voltage of 1200 V. An energy conversion efficiency of 14.9% has been achieved. The power was capable of instantaneously lighting up as many as 600 multicolor commercial LED bulbs. The record high power output for the NG is attributed to optimized structure, proper materials selection and nanoscale surface modification. This work demonstrated the practicability of using NG to harvest large-scale mechanical energy, such as footsteps, rolling wheels, wind power, and ocean waves."

You should be able to put it also in your shoes such that you may be able to power some gadgets. Thinking about it, I have seen many kids already running around with brightly lit sneakers!

I wonder how much energy you can extract from the ocean in a responsible way... Mixing up different thermal layers would probably a quite an influence on ecology.

The last available assessment report on the ecological impact seems to date from 1981 which would need to be brought up to current standards. On the other hand, this system could have a positive influence on fish population as deep cold water brings nutrients to the surface. The cold water could also be used to lower sea surface temperatures and affect hurricane genesis!

ocean fertilization might induce increased marine aerosol (DMS) emissions leading to further cooling effect but also changes in precipitation

Hehe... as far as I know the Russians, they won't miss a chance to "clean up" a few enemy satellites too...

additional information: http://atelierdna.com/?p=144

isn't this a bit of a contradiction: on the one hand: "Based on rough estimates, said Núñez-Ameni the output would be comparable to that of a conventional wind farm covering the same area" and on the other: "After completion, a Windstalk should be able to produce as much electricity as a single wind turbine, with the advantage that output could be increased with a denser array of stalks. Density is not possible with conventional turbines, which need to be spaced about three times the rotor's diameter in order to avoid air turbulence. " still, very interesting concept!

More amazing stuff from Saturn.

Europe is less far and there is also an ocean beneath the surface (at least we think...), and it's bigger. Nasa planned a mission to Europe some years ago but it was cancelled because of budget cut because of... war in Irak !

interesting and ambiguous

for Franco - nothing revolutionary to me but OK ...

A good occasion to get the idea out of the idea pool...?

"In an effort to help solve the black hole information paradox that has immersed theoretical physics in an ocean of soul searching for the past two years, two researchers have thrown their hats into the ring with a novel solution: Lasers. Technically, we're not talking about the little flashy devices you use to keep your cat entertained, we're talking about the underlying physics that produces laser light and applying it to information that falls into a black hole. According to the researchers, who published a paper earlier this month to the journal Classical and Quantum Gravity (abstract), the secret to sidestepping the black hole information paradox (and, by extension, the 'firewall' hypothesis that was recently argued against by Stephen Hawking) lies in stimulated emission of radiation (the underlying physics that generates laser light) at the event horizon that is distinct from Hawking radiation, but preserves information as matter falls into a black hole."

Alvin, the only deep-diving manned submersible used for science has been upgraded, allowing scientists to explore for the 1st time the depth of the oceans down to 6500m bsl.