Here is my attempt to answer the first questions that you might have about the new White Mars paradigm, and its implications for understanding and exploring Mars. If you have any further questions, please email me and I'll do my best to answer them. If I can't answer them straight off, then I'll go and do some more work until I find an answer!

Questions

Answers

I have always been interested in the solar system and its planets. I've watched the manned and robotic missions of NASA with keen interest and maintained my knowledge of scientific research into planetology. I've also studied volcanoes and pyroclastic flows, and worked in the Oil industry where I studied deep water sedimentary process including turbidity currents and their deposits.

When Pathfinder returned its pictures of a landscape strewn with huge boulders, I was struck by the analogy to pyroclastic deposits. I recalled other workers who described Viking era images of the plains of Mars as resembling ignimbrite plains. The concept came to me that it was very hard to get a flood of liquid water on cold dry Mars, but that since CO2 dominates its atmosphere, and the temperature is so convenient for the CO2 solid/liquid transition, then perhaps something could be made of this.

I then did a lot of work, wrote a few papers, and went to the 5th International Mars Conference.

Where does the name "White Mars" come from?

I obviously have to give credit (and apologies) to Kim Stanley Robinson, who wrote an excellent fictional trilogy about possible future terraforming of Mars - Red Mars / Green Mars / Blue Mars. His novels were based on the conventional warm-wet past. When I developed the alternative "iceworld Mars" concept, I was moved to use his naming convention, since it was so evocative, and also described neatly and pithily everything about the new model. In "White Mars", Mars is no longer the Red Planet (although it has lots of red dust). It is dominated by the behaviour of CO2 ice and snow. Like water ice, these are white or clear. Massive CO2 ice does not show the distinctive blue colour of thick glacier ice. As far as I can tell it is totally colourless.

Interestingly, Robinson has moved on from Mars to write another novel about Antartctica. Some reviewers have nicknamed this book "White Mars"! Robinson is also associated with the Mars Society, A public movement urging manned missions to Mars.

Why is everyone else talking about Water on Mars?

Apart from the prior work of Lowell, there has always been a deep human desire to see other planets as Earth-like, and potentially harbouring life. Without water, Mars might be more boring and less able to generate funding for NASA missions and scientific research.  Almost inevitably, over the years public funding has gone to those who propose watery Mars models, rather than those who don't. This isn't the objective progress of "pure" science, but is the result of funding committees and political pressure (perhaps unconscious) on science objectives to work on "interesting" problems.

The scientists who work on watery Mars models genuinely beleive their models are the best way to view Mars. After all, there is lots of evidence on the surface of Mars that could be interpreted as the signs of water erosion. It just gets a bit complex explaining how the water gets there and where it goes after it's done its job - especially on a planet which is now cold and dry in the extreme

Why should I believe you?

In Science, the word "believe" is a strange one. I can't simply ask you to believe what I'm saying and "proof" is a difficult concept when we're talking about events long in the past on another planet. All I can ask is that you understand what I'm saying, and what the proponents of water on Mars are saying. Then it's up to you to decide which is more reasonable, or more likely. Obviously, I think that the water proponents are arguing a difficult case, but you have to make up your own mind. There are lots of resources on the internet about Mars, most selling the conventional line about water on Mars. Read some of them, and read my pages. Ask questions.

What are the consequences for Mars exploration?

One of the main and immediate consequences is that we're diverting scarce resources in the planetary programme into searching for water on Mars (i.e. Life on Mars). Now some of that will reap a benefit anyway in terms of inproving our understanding of Mars in general, but a lot of it is going to be seen as a wasted effort. we need to return to the basics of Mars exploration, to visit the planet with robot probes that have robust survivable mission profiles. No 30-minute airplane flights, for instance, we need 3-year orbiters with continuous detailed mapping and a real Mars rover -" A Marsokhod".

We need another try at a Polar Lander, to dig into and sample the permafrost layers. Will we find CO2 clathrates,  dry ice, or water ice? We need more orbiters with detailed imaging capability and more laser altimeters to produce really detailed topographic maps. All this costs money, which needs public support. I'm worried that there may be a bursting of the bubble of public confidence in Mars exploration when the wheels fall of the Water/Life on Mars bandwagon. The longer that we delay in changing our minds about Water on Mars, the harder will be the fall and the harsher the criticism.

Does this mean we can't Terraform Mars?

I'm not sure about this. Obviously if Mars never had a warm and wet climate in the past, we can't "return" to that state. However, my models of atmospheric response to energy input are perfectly compatible with terraforming by warming the poles to stop them freezing. My models are based on those of Zubrin & McKay who propose that we can "easily" warm the poles of Mars. I think they're being a bit lenient with some of the equations, principally the rate of spontaneous heat transport to the poles by a thick atmosphere. The consequence of this is that in order to have naturally occurring liquid water at Mars' equator, we need to totally melt and vaporise its CO2 inventory and generate an inhospitable 5 bar CO2 atmosphere. This would be lethal to humans and all higher life forms, but survivable by extremophiles.

The trouble is, the CO2 would then dissolve in the water and attack the rock and dust to form carbonates. In a few thousands or hundred thousand years, the new atmosphere would collapse again, unless prodigious efforts were undertaken to keep the planet warm artificially. Alternatively, we could wait a couple of billion years until the Sun warms up more. Then Mars will be much easier to terraform, but humans will no longer be around for one reason or another (evolution, anihilation, space travel to or from Earth etc.).

Isn't there lots of evidence for Water on Mars?

That depends on how you interpret it. There is also lots of evidence against water on Mars. The present day surface and soil is extremely dry and there is very little water in the polar caps. Analysis of the SNC meteorites also shows that they are very dry compared to equivalent Earth rocks. In the end, the only strong argument for water on Mars (other than during the main bombardment, when conditions were obviously very different) are the Outburst "flood" channels. Unfortunately, it gets very difficult to explain how repeated huge outbursts of water can occur on a planet with essentially no water recycling processes in its atmosphere. If we could find a way to explain the "floods" without using liquid water, then all the paradoxes of Mars disappear.

What about the Martian Ocean?

The evidence for a Martian ocean is inconsistent and incomplete. The White Mars paradigm, and several other models for Mars that don't involve oceans, all predict that the Northern Plains should be ice-rich. The Martian ocean hypothesis doesn't offer much more but does add one more to the list of paradoxes. If there was an ocean of liquid water on Mars in the past, even if it was ice-covered, then the atmosphere would have been much wetter and we should see signs of snow and rain at the same time as the ocean existed. We don't.

Also, if a large ocean existed in the northern plains, then there should be extensive deposits of carbonate rocks on the bed of that ocean. We don't see any carbonates, even where young impact craters penetrate through any covering layers of wind-blown dust and sediment.

What about the dendritic Valley Networks?

The Dendritic Valley networks are intimately associated with large impact craters in ancient Noachian terrain. They date back to at least 3.5 to 3.8 billion years ago when the outer surface of Mars was still being formed by giant impacts. MGS images of them show thay are immensely degraded when seen in detail, and they have in part been exhumed.

In short, the dendritic networks are a snapshot of what happened briefly on Mars some 3.5 to 3.8 billion years ago and are almost entirely irrelevant to the outburst "floods" or the present state of Mars (other than that they demonmstarate that early Mars had some active volatiles). The "White Mars" model explains how these networks were formed by transient local thermal events associated with major impacts. Each imnpact vaporised CO2 and water ice in the regolith, forming a temporary local "bubble" atmosphere and perhaps an ephemeral hydrological system. As the atmosphere collapsed again, lashings of rain and snow scoured the unconsolidated dusty regolith of Mars, eroding deep ravines in a very short time before the planetary ice age set in again.

Indeed, it is possible that liquid CO2 flowing under a very transient 5-10 bar CO2 atmosphere could have been the active agent, rather than water, but this point is very speculative and not required in the basic "White Mars" model for early Mars.

How can rocks be transported hundreds of kilometres by gas?

This is one of the difficult points with the "White Mars" model. I can demonstrate on Earth that density flows from volcanoes have transported boulders for tens or even hundreds of km. However there are no examples of volcanic density flows (pyroclastic flows) persisting for thousands of km. One reason for this is that the energy for a pyroclastic flow comes from hot rock which cools after many minutes or at most an hour. Even with supersonic flow speeds this limits the travel distance to at most a few hundred km.

On Mars, the energy source is degassing of CO2-rich ices. This is constrained by the rate of energy supply to the crystals, which is controlled by internal friction. If the flow starts to die, then friction increases and the grains get crushed and warmed, so they give out more CO2. Obviously, a more complete scientific analysis of this process needs to be completed, which is part of the further work. At the present time, it isn't clear whether the Pathfinder boulders have literally been transported for a thousand km, or merely a few tens or hundreds of km from a rocky outcrop or crater rim that the flow encountered and demolished.

There is absolutely no problem at all with transporting fine debris for thousands of km in a density flow. Submarine turbidites on Earth have been doing this for billions of years, and continue to do so today.

Why aren't there volcanoes all over Mars if your cryoclastic flows are like volcanoes on Earth?

Although the flow mechanism of the gas & dust cloud is similar to that of pyroclastic flows in Terrestrial volcanic provinces, the source of the flows is different. On Earth, some pyroclastic flows are generated by collapse of eruption columns from volcanic vents, but others are generated by collapse of pasty lava domes, or as secondary flows when thick ash falls slide off the edge of steep hillsides. It is this latter mode of origin that most closely matches the cryoclastic flows on Mars.

There, collapse of layered terrain which consists of dust, thin rock layers, and volatile-rich ice generates the turbulent cloud that forms the density flow. Thus there will be no volcanic cones at the heads of the cryoclastic flows but instead they will emerge essentially fully formed from collapse zones - the Martian Chaotic Terrain.

Why wasn't there an ocean on Mars if your cryoclastic flows are like submarine turbidites on Earth?

Although the flow mechanism of the gas and dust cloud across the surface of Mars is similar to the flow of a cloud of debris and water along the ocean floor on Earth, the similarity is only one of mechanism. On Earth the density flow consists of debris mixed with the surrounding fluid - water. On Mars the flow consists of Debris mized with the surrounding fluid - CO2 gas. In addition, on Mars, the debris contains CO2-generating ices which prolong the flow allowing the transport of coarse debris for longer distances than on Earth.

What further work needs doing for the "White Mars" paradigm?

As mentioned above, there is some fine tuning to be done. I want to do more work on the explosive power of released CO2. I also want to build a small-scale model of a river flowing with liquid CO2 in a pressure vessel - with transparent walls so that we can observe the flow properties and erosion effects on dusty substrates. Obviously, these two objectives imply that careful consideration to safety is needed. I'd hate to prove my thesis about explosive power by having my aparatus go bang!

I want to do more work on the solvent extraction properties of liquid and supercritical CO2 in Mars' subsurface. This work has been done with water, and failed to explain the odd chemistry of Martian soil. Perhaps CO2 has some answers.

I also want to do some work with CO2 clathrates and measure their outgassing rates at a variety of pressures and temperatures, and to see how gentle (or vigorous) grinding, as in a cryoclastic flow, will assist.

I also need to build better atmospheric models, and continue the comparison exercise with Terrestrial flows.

And I need to publ;ish all of this, and seek grant support for further studies. In short, I'll be busy, but not too busy to answer your questions about "White Mars", especially if it helps plug a gap in the story. Just email me.

What can I do about "White Mars"?

If you're really interested about the consequences of a "White Mars" scenario for Mars, or other planets, I'd be happy to correspond with you and give you some pointers for research of your own. I will be fairly busy so I can't offer much more than guidance, unless you hit upon an interesting topic.

What you can do is take the time to understand what I'm saying and if the chance arises, to ask questions when people state that Mars must have been wet in the past. Ask them is they really know that, or are just repeating something they read in the newspaper, or on the Internet, or heard on TV. Refer them to my webpages and ask them to think, not just follow.

How do I learn more about Mars?

There are plenty of resources on the web about Mars, its exploration, and theories about water on Mars. You can track these down with a search engine, through the NASA websites, or via my links page. Remember as you read all this material that the case for water on Mars is far from proven. Most of these sites take it as a given fact and few discuss the very real difficulties about wet Mars models. Do learn the facts and look at the pictures.