Venus was transformed from a haven for water to a fiery hell by an runaway greenhouse effect, concludes the European Space Agency (ESA), after studying data from the Venus Express, which has been orbiting Venus since April 2006.
Venus today is a hellish place with surface temperatures of over 400°C (752°Fahrenheit), winds blowing at speeds of over 100 m/s (224 mph) and pressure a hundred times that on Earth, a pressure equivalent, on Earth, to being one km (0.62 miles) under the sea.
Hakan Svedhem, ESA scientist and lead author of one of eight studies published on Wednesday in the British journal Nature, says that Earth and Venus have nearly the same mass, size and density, and have about the same amount of carbon dioxide (CO2). In the past, Venus was much more Earth-like and was partially covered with water, like oceans, the ESA scientists believe.
How could a world so similar to Earth have turned into such a noxious and inhospitable place? The answer is planetary warming. At some point, atmospheric carbon triggered a runaway warming on Venus that boiled away the oceans. As water vapour is a greenhouse gas, this further trapped solar heat, causing the planet to heat up even more. So, more surface water evaporated, and eventually dissipated into space. It was a "positive feedback" -- a vicious circle of self-reinforcing warming which slowly dessicated the planet.
"Eventually the oceans began to boil," said David Grinspoon, a Venus Express interdisciplinary scientist from the Denver Museum of Nature and Science, Colorado, USA. "You wound up with what we call a runaway greenhouse effect," Hakan Svedhem says. Venus Express found hydrogen and oxygen ions escaping in a two to one ratio, meaning that water vapour in the atmosphere — the little that is left of what they believe were once oceans — is still disappearing.
While most of Earth's carbon store remained locked up in the soil, rocks and oceans, on Venus it went into the atmosphere, resulting in Venus' atmosphere now consisting of about 95% carbon dioxide.
“Earth is moving along the curve that connects it to Venus,†warns Dmitry Titov, science coordinator of the Venus Express mission.
References:
Venus Express - European Space Agency (ESA)
http://www.esa.int/SPECIALS/Venus_Express/SEMGK373R8F_0.html
Venus inferno due to 'runaway greenhouse effect', say scientists
http://www.physorg.com/news115477239.html
Probe likens young Venus to Earth
http://physicsworld.com/cws/article/news/32018
European mission reports from Venus
http://www.nature.com/nature/journal/v437/n7062/full/4371071a.html
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Comments: 37
Keep in mind though, that to do anything about our own situation here on Earth would require that we spend money on it and inconvenience ourselves. We'd rather die and allow our children to perish than to lower our standard of living. It's similar to the seatbelt thing. We'd rather increase our chances of injury or death than feel confined, or wriinkle our clothes, or let someone else tell us what to do. We have our priorities.
Most hydrogen is currently made from fossil fuel, which in theory adds some water eventually, but as a fluid, rather than as a vapor. Preferably, hydrogen is made through electrolysis of water, which merely uses tap-water that's already part of the water supply and splits it into hydrogen and oxygen. A fuel cell subsequently recombines the hydrogen with oxygen from the air into water. Only when water vapor is released high up in the sky would it become significant as a forcing factor. Even when used in aviation, it wouldn't be much of a problem in the case of smaller planes that don't fly as high as jets do.
Sure, Venus is closer to the sun, but in the case of Venus there were no human beings burning fossil fuel, burning forests, breeding methane-producing cattle, making concrete and fertilizers, and otherwise engaging in greenhouse gas releasing activities.
The evidence of antropogenic global warming is mounting and there is no alternative scientific explanation that makes sense. Instead, there are only myths that are knowingly and deliberately spread by narrow-minded people who seek some short-term self-interests. For those who want to review the various myths, have a look at:
http://environment.newscientist.com/climatemyths
In conclusion, we cannot afford to find out by way of trial and error where the tipping point was for Earth to experience a similar runaway greenhouse effect. We simply have to stay on the safe side and we must avoid getting to a stage where severe positive feedback will kick in. There are time lags between rises in greenhouse gases and their impact on climate and associated positive feedback. These time lags mean that the longer we delay effective action, the more severe the impacts will eventually be and the more difficult and expensive it will be to take effective action.
Interpretation for the rest of us…..FEAR MONGERING! If you don't do as I say we will all perish!
Pay no attention to the ignorant detractors on this thread. They will still doubtless think it's all sunspots when Miami goes under water and continue to rant about Al Gore's electric bill on their deathbeds.
"but feel free to elaborate if you feel that I missed something."
What you miss is the very possibility that man can not effect the environment to the extent that you suggest.
http://www.eia.doe.gov/oiaf/1605/ggccebro/chapter1.html
When we look a C02 in the atmosphere from the PPM view point the rise from 280 ppm C02 to almost 380 ppm seems substantial, but when we look at the gross amount of C02 in the atmosphere over 700 billion metric tons, and that humans produce less than 1% of that amount annually it doesn't take a climatologist to figure out that even if we completely eliminate our C02 production it will have very little effect on our environment.
The atmosphere is a delicate balance. Concentrations naturally occurring in the atmosphere are needed to take Earth's temperature up all the way from the minus 454 degrees Fahrenheit (3 degrees Kelvin) of deep space to Earth's average temperature before anthropogenic global warming started to kick in. Anthropogenic emissions have a substantial additional impact on temperatures.
We can expect increased average temperatures on Earth to rise, even if we could eliminate all our CO2 production. Until now, about 45% of anthropogenic CO2 has remained in the atmosphere, while about 30% has been taken up by the oceans and the remainder has been taken up by the terrestrial biosphere. As temperatures increase, we risk crossing certain tipping points beyond which sudden irreversible and catastrophic changes occur. We can expect a reduction in the capacity of land and oceans to absorb anthropogenic CO2. As a result, an increasingly large fraction of anthropogenic CO2 would stay in the atmosphere under a warmer climate, while increased temperatures caused more evaporation of water from the oceans and from melting glaciers and snow. The result could be a runaway greenhouse effect.
As said, we cannot afford to find out by way of trial and error where the tipping point was for Earth to experience a runaway greenhouse effect. We simply have to stay on the safe side and we must avoid getting to a stage where severe positive feedback will kick in.
You fully admit the reducing mans C02 output will not stop the planet from warming yet you think we should stifle the economies of the world by imposing a carbon tax, thereby as a result of that tax restricting peoples ability to move forward towards a cleaner environment.
You even reject the greatest source of clean, stable energy currently available today, nuclear. Not because it doesn't provide clean energy but because it would stand in the way of your preferred hydrogen, and your hopes for the future. You would rather allow a continued increase in C02 output in the near future in order to satisfy your biases, because by allowing nuclear to cut that C02 output hydrogen will have to wait a few years.
So apparently cutting C02 output is NOT your priority
Sam you (and many others) are inflicted with the mindset of "do something even if it is wrong" and the reason that mindset exists is because it is to difficult for many people to accept the idea that there may be nothing we can do about the environment, if the planet warms, it warms and all the taxes imposed wont make a difference.
The planet may have been heading towards global warming even before man began using fossil fuels.
The C02 level was rising even before we began using coal in large amounts.
There was a time when the claimed consensus of the ICCP was that the difference in surface tempture past and present proved the existence of global warming, it has since been proven that there were other factors in those records besides global warming that accounted for the difference.
"The scientists do not agree with that, and i see no reason to tolerate arguments that the scientists are clueless."
Scientists are people too they are subject to mistakes and biases to the desire to advance their careers to make an income to support their families, they have egos just like the rest of us and will defend their positions by decrying other scientists position.
IN other words scientists are human with all of the same faults the rest of us have.
And it was other scientists who are called skeptics that revealed this flaw in the ICCP's assumptions.
These skeptical scientists also know science.
As I explained many times before, the wrong choice for nuclear would keep the existing energy monopolies in place and would prevent us from building the very infrastructure we need to reduce emissions.
In Dan's remarks, we can read further warnings against nuclear. If the sign says "Do Not Hit Red Button", then obviously we shouldn't put someone in charge of that button who tells us that perhaps what the sign says was wrong. We definitely don't need someone there who suggests to experiment with the buttons, as if that could be more economic than reading the manual.
"Safety and security already make nuclear prohibitively expensive."
There is no energy source in society today that can equal nuclear's safety record, 13'000 combined operational years with only two serious accidents. Even when we look at employee injuries the nuclear field is one of the safest.
Security is NOT a serious issue with nuclear power plants.
"As I explained many times before, the wrong choice for nuclear would keep the existing energy monopolies in place and would prevent us from building the very infrastructure we need to reduce emissions."
And if it is society's choice to continue with these monopolies (which is what is most likely to happen) then that's exactly what we will do.
Dan: "There is no energy source in society today that can equal nuclear's safety record."
That kind of irresponsible attitude handed control of Chernobyl over to the idiots who started to experiment with the buttons. If the sign says "Do Not Hit Red Button", then obviously we shouldn't put someone in charge of that button who tells us that perhaps what the sign says was wrong. We definitely don't need someone there who suggests to experiment with the buttons, as if that could be more economic than reading the manual. Given the huge risks of nuclear, we obviously shouldn't put people in charge who close their eyes for the risks or who deliberately hide the true extent of safety and security risks.
Dan: "And if it is society's choice to continue with these monopolies (which is what is most likely to happen) then that's exactly what we will do."
There's no indication that nuclear is likely. The contrary! As recent survey shows, if Americans could tell their power company/utility where to get the power from for household use, 58% would want wind, solar and other clean-energy technologies, 26% expressed no preference, while just 11% said nuclear power.
A Post Fossil-Fuel America: Are Americans Ready to Make the Shift?
When claims to know what voters want are not based on solid research, then how credible are these other claims, such as about the safety and security of nuclear?
People who knowingly and deliberately distort the facts, ignore and belittle safety and security risks, who leave important parts out of the cost picture and who ridicule the obvious benefits of more distributed networks, such people cannot be trusted on vital decisions about the security and safety of so many people.
That is a post of a person who is desperate.
You have tried to counter my claims with sheer unadulterated fear mongering.
Not one fact have you posted to challenge the facts I have posted.
Except that you quoted a poll, but I have my own poll Sam, 60+% of adults think that nuclear should be a part of the answer and 70+% of college educated adults think that nuclear should be a part of our energy mix.
Security is not an issue because nuclear waste can be securely contained.
All of your Oh My God something bad might happen is nothing more than fear mongering and you can't validate it.
You have not posted facts, you continue to twist and distort things, proving that we cannot trust your claims. At another article, you just took things out of context again.
Dan: "Security is not an issue because nuclear waste can be securely contained."
Statements that nuclear waste "can be securely contained" are not credible when they come from someone who just said that security is "NOT a serious issue" with nuclear power plants. In each of these remarks, we can read further warnings against nuclear.
In past articles, in many discussions with you and others I have posted an enormous amounts of facts from a wide variety of sources which show nuclear to be clean, safe and one of the most economical sources of energy available.
It is you who refuse to accept the facts and instead rely on your unfounded and unsupported fear. You make comments like, "Statements that nuclear waste "can be securely contained" are not credible" but can't offer any valid reason why you believe nuclear waste can not be securely contained, and the reason why you can't is because there is no valid reason why nuclear waste can't be securely contained, it is just that you fear it can't.
I only lack credibility in your mind!
Most everyone else will review the facts about the safety of nuclear and decide it is NOT the hazard you think it is.
The fact that you believe it is a contributor to the corruption of our society will not even come into the discussion, because we need (and most people realize this) clean energy in the near future and should not wait for the hydrogen economy to get it.
Dan, you keep undermining the little credibility you had in the first place by posting comments like "Security is NOT a serious issue with nuclear power plants" and "Scientists are people too they are subject to mistakes and biases". Under another one of my recent articles, you blatantly quote figures out of context and then refuse to admit this. That only proves that you cannot be trusted to take decisions regarding the handling of nuclear material, and you can only blame yourself for your lack of credibility, Dan. Most everyone else who sees these comments will agree with this conclusion.
Well Sam,
You could be a bit more specific about what I quoted out of context (I would then prove you wrong again) but if you did that I could show that these attempted attacks on my credibility of yours are unfounded.
Ten unsolicited points from the world's worst connection. Merry whatever you celebrate!
In what ways is France's Nuclear power generation a huge problem? You state that they had to import power in 2003, but why is what happened in 2003 not solvable with current technology to easily avoid the same thing in the future? With the majority of power in France generated by nuclear reactors, can you name some safety and security incidents that are not solvable and should give us concern as to why we could not proceed safely down the same path?