what if in many many thousands of years by the time mars is terraformed that we "accidently" mess that on \e up to. Could we possibly have the technology to explore other horizons planets or moons withdangerous gases we may then be able to handle. Venus for example has a light ozone but too dangerous but moons of jupiter or saturn may be able to be used food can be grown on mars still and transported to the moons. But what do you think would happen if we did indeed mess mars up to. h34r: <_<

following up what happens if we can not make it to mars at all. We may not realise but one day for some generation there lifes will slowly end. Or in one big masicure in an unsee able and unstoppable moment.

I think that if we were able to terraform Mars, the problem would be that it could only be a relatively short term measure. Mars doesn't have the mass to be able to hold on to a thick atmosphere or surface water for any length of time as has been shown by the evidence of the current rover explorers.

I for one think that we should not attempt to do this anyway. When humans meddle with nature it always seems to lead to disaster!

Jake B)

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Of all the things I've ever lost, I miss my mind the most!

Bah humbug!

We have been meddling with nature since we made our first tool and even before by selecting whatever was included in our diet and the actions we took to acquire its constituents. Living organisms cannot avoid meddling with nature. We are one of the few, perhaps the only, species capable of anticipating disaster and taking remedial action to the benefit of both ourselves and other species as well. We do and will continue to make mistakes; the trick is to make sure that the benefits of our actions outweigh the mistakes.

We can and should consider the terraforming of Mars and Venus, and, in the case of Mars, consider whether its colonization requires terraforming and whether terraforming is the optimum method of colonization as opposed to burrowing in. Will we make mistakes in so doing? Very likely. We must keep the feedback loops sufficiently short so the mistakes can be corrected prior to reaching a point of no return.

Wouldn't it be convenient if our genetic engineers could produce a "living canopy" consisting of especially engineered microbes living and forming a "continuous mat" suspended by its buoyancy high in the martian atmosphere that would prevent or significantly impede the escape of disassociated hydrogen. If so, we could cause a comfortable atmosphere to form under and be retained by this living canopy. This biotechnology would help us to terraform the larger moons in the system as well.

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For those inclined to oppose human meddling with the structure of the universe or the composition and configuration of objects and groups of objects within the universe, consider:
Whether there is a limit to the magnitude of a modulation of chaos below which order remains invariant? Or, is order but a fiction invented by perspectives applied over finite, however large, time intervals?

That's telling him!

Apparently some people don't live in cities where storm sewers and water mains have been put in place to service millions of homes in countless cities. Alternatively some people have never seen the collosal irrigation projects in North America's prairies that grow an abundance of cheap food for almost billions of consumers.

Terraforming Mars doesn’t have to be an all or nothing proposition. We don’t need a Martian atmosphere with 100% of Earth pressure, 20% oxygen and 80% nitrogen. But higher atmos-pheric pressure than currently exists would be helpful in putting less stress on Martian suits, vehi-cles and habitats.

Martians would probably breathe a mixture of 40% or higher oxygen and the balance nitrogen and helium at a presume of 50% or less of Earth’s atmosphere. Pressure on Mars wouldn’t have to increase by anything approaching this 50% level before making a very substantial contribution to Martian livability.

A denser atmosphere would provide increased protection from meteors and radiation. Greenhouse gases like water vapor, carbon dioxide and methane would make for a warmer Mars. Even modest amounts of ozone in the upper atmosphere would significantly reduce ultraviolet radiation at the surface; and there may be other gases that would act as partial radiation barriers.

If the Martian colonists were to create a 10% of Earth pressure atmosphere that provided some protection from radiation and meteors, and provided a significant greenhouse effect, there world would be a lot more habitable, safe and convenient.

It seems to me that any life that was ever on Mars must be in pretty bad shape if not extinct. Mother Nature seems to have done a poor job on Mars, and looks to me like she could use a lot of help. What she’s done on Mars makes human meddling seem awfully benign.

Bob

i disagree we have screwed most attemts to be a fully idealistic world. With this we have made things extinct others never to be seen again. All because of needing to be faster more powerful or should i say more pollutive and population growth i ssaykill stax of people if you want to have that but have oxygen and an ozone layer but would we do that no. We need to act upon our actions and not develp in life evolvement much further as it will just lead to the destruction of our race.

These insights are invaluable, and certainly do shame the human race as for its many failings and lost opportuniites.

But meddling with nature is a fact of life for many species: some sea otters will use small rocks to smash mussles in order get at the insides, ants build anthills but actually disturb the lay of the land, hornets and birds build elaborate nests in trees and leave a mess behind for the next year, beavers making dams block up waterways that eventually cause floods along the higher shoreline, ... the list of species other than mankind making an artificial environment for themselves without regard to other species could go on and on.

To wholescale condem all of mankind's accomplishments and dreams is too pessimistic an approach. Your statements would mean that the irrigation projects should never have been built and must be dismantled immediately. Also, countries where dams have been built to reclaim farmland from the sea should let the sea resurge and flood that farmland even if houses are there.

Your statements also seem to completely ignore the dynamic nature of Earth and nature itself -- the Ice Ages were of no fault of man, nor the K/T event, nor the extinction of the trilobite. Check out the Arizona meteor crater sometime and while you are in the neighborhood visit the petrifed forest. There are remnants of trees that resemble today's common horsetail weed but lived when the Earth's atmosphere was drastically different than now. In fact, a case could be made for space hydroponics experiments to actually use the horsetail weed in low oxygen environments to see if it could be a source of food, because it would grow considerably taller in a non-Quaternary environment.

My point is that there are unfortunately some trade offs to the advancement of civilization and we do need critics to make sure that the loss/benefit ratio is worth defending. Responsible resource management is needed to keep pollution to a minimum and the development of human potential to a maximum.

I think that a fairly blase comment I made has stirred up some good thoughts, so I'll expand on mine.

yes, there is truth as spaceboy says in the huge strides we have made in agriculture etc, but to generalise on it by talking about the plains of North America is folly. Man's effects on the planet have to be looked at in far larger terms, as there have been huge agricultural disasters such as the removal of huge expanses of diverse rainforest for short term agricultural use too, which has added to the problem of climate change.

We are currently seeing the effects of human actions on our own planet in the form of climate change. Nasa's data is the prime proof of this climate change. Yes proof. There will be those of you who don't think that we're having an effect, but we are. The icecaps are melting a great deal faster than they would have if we weren't pumping carbon dioxide in to the atmosphere-fact. We have managed to increase the temperature of Earth by a degree or two in no time at all. A couple of hundred years is not even the blink of an eye in the developement of this planet.

With those facts in mind I stand by the quote which a few of you have argued against which was 'When humans meddle with nature it always seems to lead to disaster!' It has and will lead to disaster here. Ask anyone in the Philapines where they have suspended all logging due to their recent storms. If we try and affect Mars' climate I'm sure it would be a very short term, measure which would ultimately strip the place of its beauty.

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Of all the things I've ever lost, I miss my mind the most!

If its Mars you want to go to then take your weather with you. I dont think tera forming Mars is a viable idea. I would sagest the large biosphear, but the roof had better be real tough and the structure very secure. Becouse of the thin and low presure atmosphear the possible impacting metior could be a problem for my Dome. This dome would be able to suport a vilage sized out post. Trees and all.

Viewpoints noted, but there is lots of room for skepticism for those on the other side of this quasi debate: a goal to achieve the best possible cost/benefit ratio

It is generally accepted that the not-so-ancient Romans aided significantly to the growth of the Sahara Desert through massive tree cutting for sea ship construction. Not exactly environmental stewards, but then they brought the concept of organized civilizastion to the world. Obscure but mounting evidence in Egypt has demonstrated that the great pyrimids were built in, and at the expensse of, the tropical rain forest at that vicinity. Certainly not environmental stewards there either, but they brought us the basis of organized astronomy via calenders: for religious observances, flooding dates for agricultural purposes, certainly mathematics where a metric system was developed that today presents profound competition to the SI politically correct crowd.

I have not seen any paleo-climatological data from the holocene that comments on the effects of those civilizations. Perhaps it is published somewhere but in order to give credence to the Amazon sky-is-falling concept that info should be made available (Note that I am not advocating cutting down every last tree). It is postulated that most O2 is generated by water bourne photosynthetic organisims and not land based life. And that an acre of corn will produce more O2 than an acre of trees ---- plus feed people at the same time.

One more item for skepticism on the 100% mankinds' fault hypothesis: the last interglacial was much warmer than the temperatures we are experiencing today. And the next ice age could be as soon as 70,000 years away if we don't do something about it!

If there are errors in what was written here then blast away -- constructive criticism is the hallmark of these Universe Today forums.

GOURDHEAD makes a good point!!!

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Challenging Limits

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One more comment: I would prefer to settle for the zero cost/infinite benefit ratio. I accept that this is impossible, and apologies Jake if any offense was taken. I just don't completely agree that "When humans meddle with nature it always seems to lead to disaster".

“there have been huge agricultural disasters such as the removal of huge expanses of diverse rainforest for short term agricultural use too, which has added to the problem of climate change”

There is zero evidence that anything having to do with changes in rainforests (formerly known as jungles) have anything to do with any climate change. This is just cant.

Try to think a little bit critically, and maybe even consider some facts: What percentage of the Earth’s surface was ever during the Holocene covered in rainforest? What is the difference between then and now? What percentage less photosynthesis takes place on agricultural land as opposed to rainforests?

I don’t have any figures about rainforests handy, but I do have some figures for forestation in the United States from the Statistical Abstract of the United States, 120th edition, Table 1148: Total forest land: 1987, 731 million acres; 1992, 737 million acres, 1996, 746 million acres.

According to the UN’s Food and Agricultural Organization Production Yearbooks 1949-1995, the percent of the Earth’s land area covered in forest rose from 30% in 1950 to 32% in 1994. Such figures will, hopefully, give some pause to the almost religious belief that deforestation is a critical problem in global warming.

The amount of photosynthesis taking place on agricultural land is not significantly less than that taking place in forests. Crop plants cover nearly all of the land, grow very rapidly and power the process with photosynthesis. Crops are also protected to some extent from pests, drought, fire, and other factors which adversely affect the photosynthesis taking place in forests. Harvests do reduce photosynthesis until a new crop begins to grow.

Even if there were a 10% reduction in relative photosynthesis amounts, and even if forest land had been reduced by 10%; that’s still a reduction of only 1% of land based photosynthesis. The water that covers 70% of the Earth‘s surface participates in at least half of the photosynthesis that occurs on Earth.

We are left with a reduction in photosynthesis of one-half percent being a gross overestimate—and probably pointing in the wrong direction.

Bob

“the next ice age could be as soon as 70,000 years away”

The next ice ago is almost certainly due to come much, much sooner; perhaps by the end of this century.

The last glaciation, the Wisconsin lasted about 100 thousand years, and was preceded by an inter-glacial period similar to the current inter-glacial period and lasting about twenty thousand years. The Wisconsin glaciation was one of a series of glaciations that have occurred in a complex pattern over the last three million years or so with inter-glacial period lasting around twenty thousand years but varying widely.

The Wisconsin glacial maximum was about 18,000 years ago, and the Holocene is about 11,000 years old. Time is running out for us.

Glaciation is an unstable process because snow reflects more Sunlight, and thus has a greater cooling effect, than water or land, whether vegetated or bare. Once a summer occurs in which the snow has not melted, the likelihood of another summer without snow melt increases. Even 50 years of snow accumulation will result in considerable extension of existing glaciers and the formation of new ice sheets hundreds of meters thick with extensive new glaciers.

Prior to three million years ago the Earth hadn't had major glaciations for over 500 million years.

Bob

"It is generally accepted that the not-so-ancient Romans aided significantly to the growth of the Sahara Desert through massive tree cutting for sea ship construction."

Who is generally accepting this idea? What is your source for this?

I am not going to buy in to this idea untill the evedance is presented; I believe these prosesses are part of the Earths 'Normal'cycle of change.
Did I understand corectly the Ice ages have a history of only 500 mill yrs. I did not know that. So was the earth warmer then? Whats all this global warming ..rubbish? by the look of this it might be.
Do we need to fear the onset of an ice age? Could we not prapare for this. Its not here yet, or any time soon. What would we need to do to insure cropp failyer is not our undoing. What order of events brings the end of an ice age,? can we do this?
Is any of this actually happening? Warming, Cooling. I dont know what to believe, and I suspect that its all going to keep right on happening that way regardless of mans pathetic attemps to change things. Noteing Bobs reaserch into the reforesting of the USA. I dont think we should worrey about the impending ice sheet just yet.

Earth was essentially Ice Age free from about 500 million years ago to about three million years ago.

Throughout the Cenozoic, beginning around 65 million years, the Earth has cooled, rather erratically, but sufficiently such that about three million years ago the Earth was cool enough for glaciation events to oc-cur. And, for the last three million years, an irregular pattern of glaciations has occurred, characterized by relatively short interglacial periods such as the one we are in now.

Throughout most of geologic time, the climate has been warmer than it is today. This is difficult to explain since we know that the Sun has been getting warmer during the entire existence of the Earth.

But it makes for a very interesting and challenging puzzle.

Bob

The hypthesis that human activity may cause global warming is very powerful and very important. It runs like this: CO2 is a greenhouse gas that, in large quantities in the atmosphere, will cause the world to heat up. Humans put CO2 in the atmosphere (and other greenhouse gases), and the amount of CO2 in the atmosphere has gone up. Therefore, the world will heat up because of human activity.

Unfortunately, climate, like most other things, is not so simple. It’s argued that the effect of the human caused CO2 will be too small to be noticed, oceans will absorb the CO2, and plants will just grow more and use up most of the CO2. Also, water vapor is the most significant greenhouse gas; and methane from cows among others is almost as significant as CO2. It might be said that the real cause of global warming was too much beef; another arrow in the quiver of the Vegan.

The complexity of climate effects might be appreciated by considering this sequence of events: Increased temperature will result in increased evaporation from the oceans, and consequently more cloud cover. The increased cloud cover will reflect more Sunlight into space in the daytime, and have a relative cooling effect; and decrease the amount of heat radiated into space at night with a relative warming effect. Which effect predominates is unknown.

Then, the effect increased cloud cover will have on photosynthesis and the consequent removal of CO2 from the atmosphere is another important element in evaluating the possibilities of climate change. The simplest assumption would be that, if there is less light, there would be less photosynthesis, and, consequently, an increase in the amount of CO2 in the atmosphere.

This, however, is probably wrong because the optimum Sunlight for photosynthesis is exceeded for a substantial part of the day with direct Sunlight. Plants have probably evolved to take best advantage of the most common conditions, not an extreme. High noon at summer solstice only occurs for an instant once a year. Cloud cover diffuses Sunlight; the light lasts longer and stresses the plants less, which weren’t using all that Sunlight anyway.

CO2 is a plant fertilizer; and warmer, wetter environments with enhanced CO2 and Sunlight conditions might be considered a plant paradise. The more photosynthesis, the faster CO2 is converted to organics, water, and oxygen.

Or, it may be that all of these mechanisms will be overwhelmed by the increased heating effect, that a new equilibrium will be established, involving a hotter Earth with other effects humans will find very unpleasant. It not a good idea to rock the boat.

Bob

Although I'm in favour of human exploration and colonisation [as if my opinion matters], I am worried by a persistent image. Some time ago, I saw a documentary on the devastation caused in Australia by introduced species, wherer no predator exists to limit numbers. A particularly striking image was a huge, pullulating mass of mice caught in a corner of a grain store. They looked for all the world like a single, quivering, living mass of tissue.

Can I really look forward to a future where humanity spreads through the universe like uncontrolled vermin? We need to make sure that wherever we go, we either take other species with us, or cultivate native ones, to keep a sense of proportion, to remind us of our origins. If we don't, we will end up as Wells' Martians, fatally arrogant about our place in the universe.