Agres, introduction & ice sheet modeling issue

In summary, Agres is a tool used for modeling ice sheets and simulating their behavior. It was developed by researchers at University of Alaska Fairbanks and has been used to study the impact of climate change on polar ice sheets. However, there are challenges and limitations in ice sheet modeling, including uncertainties in data and the complex nature of ice sheet dynamics. Improving ice sheet modeling is crucial for accurately predicting sea level rise and understanding the effects of climate change on polar regions.
  • #1
Agres
I always had an interest in science. At SUNYA, I took a lot of science, and did modeling for Jay Forrester's Club of Rome Report. My junior thesis was based on that work, and my advisors laughed at it, so I decided that I did not want a degree from SUNYA. My second choice university did not want me, so I became a chef.

A few years later, a rock climbing buddy needed somebody that understood RCRA and CERCLA, so I went to work for him at Bechtel. They noticed that I tended to get the correct answers, and I ended-up as a Senior Scientist (without ever getting a university degree). I did not write many papers, but the US-DOE Inspector General audited one of my projects and determined that it had saved taxpayers $5 billion.

My current interests are problems in current ice sheet flow and fate models; and momentum conservation models in particular. I think that any ice model that does not address the changes in the structural strength of ice as a function of temperature; and, the changes in ice's melting point as a function of pressure is not worth the time to review in detail.

I think, that regardless of the color of the ice (e.g., dark ice due to soot or algae), today, the amount of humidity in the polar atmosphere is critical. If there is water vapor overhead, the ice is going to be warmer and weaker. If the atmosphere is dry, heat will be radiated off and the ice will be colder and stronger. And, ice in a dry atmosphere will be sublimating water vapor, and thereby cooling.

I think the foundations of the ice sheets evolved to support specific ice structures, and the addition of moisture to the tops of those ice structures adds stress on the foundations.

I think that every gram of water vapor condensing on top of the ice melts ~7 grams of ice, resulting in ~8 grams of runoff, and the runoff results in potential energy being converted to heat adjacent to ice. And, I think that water in firn adds weight to the ice sheet without adding any structural strength.

I think the Lake Missoula "Floods" were in fact ice debris flows resulting from progressive structural collapse of glaciers in the Clark River valley.

The conventional theory is that the Clark River was intermittently damned by a glacier, which advance and retreated. This is based on the wave benches in the Clark River valley and evidence of ice scrapes at the south end of the valley. At Hanford, the entire management chain above me was comprised of geologists that had published papers advancing this conventional theory. That theory is everywhere. (e.g., https://en.wikipedia.org/wiki/Missoula_Floods ). However, as my management asserted that model to me (circa 1995), their arguments were tradition rather than physics and math.

The problem is that fresh water ice will only dam water to a head of about 6 m. (See for example Feynman’s introductory physics lectures. Note that he assumes equilibrium and big ice takes a while to come to equilibrium.) An advancing glacier will not dam a 300-meter deep lake. Pressure depression of the melting point of ice is commonly seen in moulin formation on Greenland. The same effect would allow water to punch through an ice dam when the water got to be more than 6 m deep. If the glacial damming theory was correct, the water in the Clark valley would have been deep, and near freezing. Thus, there would have been significant winter ice, and "ice ridges" would have formed on the wave benches. I walked the valley and did not see any. Sure, there would be ice scrapes at the mouth of the valley. There was a thousand meters of ice just up the valley. There was ice everywhere. Ice scrapes in the valley were eroded out by subsequent floods.

I assert, that in cold years the Clark River froze, with shallow ponds (less than 6) m deep forming on top of the thick ice in the summer. These shallow ponds resulted in the wave benches. In very warm years, the ponds became lakes that resulted in moulins that triggered the progressive structural collapse of the ice in the valley resulting in ice debris flows. Then, the badlands were carved by the debris flow and cavitation in the debris flow. The 30 m ripple marks of boulders at Hanford show how powerful the floods were. Such huge flows of ice, stone, and water can use cavitation to cut through columnar basalt like a warm knife through butter.

This has significant implications for how we model ice sheets in general. There are a bunch of good graduate level research topics here.
 
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  • #2
:welcome:

and I hope you'll have fun and find new insights.

It appears as if I should tell you, that we do not discuss personal theories, so in case you want to further discuss the topics above, please prove your statements by peer-reviewed papers in science journals or textbook opinions. This forum here is only meant as an opportunity for new members to say hello. Therefore I closed it. For technical questions and debates please use our technical forums. Thanks, and again, welcome to the show!
 

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