Hudson's Bay, Continental Ice Sheets, Polar Bears and Noah's Flood

“The Biggest Bears Get the Best Toys and Can Play Like Kittens”

It will be a long time before I forget the sight of a huge male rolling on his back in the ice and snow, playing with a set of cariboo antlers like a kitten might play with a ball of string. Apparently the biggest bear gets the best toy. We were told that polar bears normally cannot catch caribou but one was unlucky and the bears got it. There might not be anything cuter than a snow white young polar bear cub but when even big tough dominant males can play like kittens, it is hard to deny the charm and appeal of the lords of the arctic.

Bears lolling about in the ice and snow without any hint of discomfort, indeed with every indication of enjoyment made me think about adaptations to the harsh climate. There is an obvious adaptation to cold that humans certainly dont share - or do we? I remembered our driver's comment earlier in the day. "There is no such thing as bad weather," he said. "Only poor clothing." It can be argued that ability to make suitable clothing even if we have to kill polar bears and steal their magnificent fur and hides to cover bodies originally adapted to tropical climates is a uniquely effective human adaptation to cold. The thick double layer of fur with an underlayer of more than 4 inches of insulating fat means that the bears can remain comfortable through out the darkest coldest days of an arctic winter but the downside is that they can have major problems with overheating - not a good thing in a warming world or when trying to catch fleet footed caribou.

The adaptations of the bears are obviously to the winter cold and the task of hunting seals rather than hunting caribou. The relatively small ears and tail relative to the ancestal brown bear provide additional resistance to heat loss. The long powerful neck, strong shoulders and curved hook-like claws make it easier to pull big seals out of the water and up unto the ice. I wondered if the lack of hybernation in the males that allows them to hunt all winter was also some sort of special adaptation but learned that it just seems to be an option for bears when there is food available in the winter time. For instance the grizzly bears at the Calgary zoo are fed in winter and don't hybernate. Actually hybernation is not an entirely correct description for the state of torpor and reduced metabolism that allows normal bears, including female polar bears to survive the winter without food. I understand that they can and will arouse if disturbed, unkike ground squirels and other true hybernators where metabilism is reduced even farther.

“Going Down the Beach to Check the Sea Ice”

The shore line that stretches East of the town of Churchill Manitoba is fully exposed the north wind and ice flows drifting with the current from farther north may tend to become stranded here and freeze in place. The bears are waiting for the ice and the opportunity to hunt ring seals that must maintain breathing holes through the ice. The seals are wary and maintain many holes to make it harder for the bears to catch them but are still far more vulnerable than they would be in the open sea. Bearded seals stay closer to the edge of the ice but may also be taken by polar bears.

I was highly intrigued by the relationship between seals and sea ice and wondered what on earth they could possibly find to eat. Ice has several important properties in this regard. First of all it can be quite transparent or at least translucent so that enough light goes right through the ice to support the growth of algae and phytoplankton in the fertile water. The ice is also crystaline with many pores and channels between the crystals where small animals can hide and flourish. There are krill which are small shrimp and fish to feast on the smaller folk and seals to eat them in turn. I imagine the productivity is low during the short days and long dark nights of winter but there is apparantly still enough food below the ice for seals to make a good living. The return of the sun in spring will generate abundance under the ice. It is then that the seals must climb on top of the ice where the pups are born. Naturally the polar bears are ready and willing to take advantage of the increased vulnerability. Indeed, this is when famished mother bear with her own very young cubs abandons her winter den to take the youngsters out onto the ice for their very first seal hunt.

“Sunset in a Frozen Land and Time to Head for Home”

We were still excitedly spotting polar bears as we headed for home but now was the time when many more questions about polar bears began to pop into mind. For instance my ears had perked up and I became enormously intrigued by a comment from Les, our intrepid guide and polar bear expert, that polar bears seem to have separated from brown bears to become a separate species only about 200 thousand years ago. It is fun to speculate that an ancestral population of brown bears thrived after they learned that it was worth while to wander out onto the shore ice in spring in search of vulnerable seals with newborn pups much like female polar bears do today. It must have been a shock for the seals when a major predator appeared in an ancient safe sanctuary, Actually the scenario sounds disturbingly like the notorious Newfoundland seal hunt when human fishermen go searching for the beatiful soft white valuable coat of the young harp seal pups born on ice flows drifting from farther north.

The evolutionary time line struck me as highly significant for two reasons. First of all the earliest known skeletal evidence for an anatomically modern human being is also 200 years old which puts human beings and polar bears on the same relatively young evolutionary pathway. We are both children of the ice age. We have both survived one short interval about 125 thousand years ago when the world was about as warm as it is now and sea levels were also similar but neither species has ever experienced an even warmer world. The polar bears are obviously vulnerable to warming conditions with loss of sea ice. Humans may be considerably less vulnerable but warning bells should also be ringing loudly about prospects for continuing human comfort and well being. Maybe caring about polar bears is good practice for caring about humankind.

Foretunately there are many people who do care. About 10,000 people now travel to Churchill Manitoba on the shores of Hudson's Bay every November to visit the bears waiting for the sea ice to form. Some people who care a lot about polar bears and what they can teach about ourselves and the world at large include: Norbert Rossing, an extraordinary German photographer. Robert Buchanan of Polar Bears International with his deft corporate touch, Dr Andrew Derocher, Canadian polar bear scientist, Cassie Seagle and Brendan Cummings,legal experts and environmental activists with the Center for Biolgical Diversity. The later is the organization that is pressing to have polar bears recognized as endangered by climate change under American law which would then have the interesting effect of requiring the American federal government to take action on climate change.

“More about the Meltdown and Speculation about Noah's Flood”

During the long flight home I kept imagining an ice sheet below our wings and wondered if I would ever have a chance to make a similar journey into the frozen heart Antarctica. I also had fun remembering landforms seen on the surface below that are remnants of the ice age - terminal moraines, eskers, eratics which are boulders transported hundreds of miles by the slow flow of the ice, huge dry lake beds, broad valleys that once held big rivers, wetlands and sloughs so important for ducks and geese with mineral and organic sediments deposited under very different by climate conditions, knob and kettle terain where isolated patches of ice sheet melted and disintegrtated, big lakes that are tiny remnants of huge Lake Agassiz, sand dunes and gravel deposits, glacial till which is a churned mixture of gravel and clay a few feet or a few inches under the thin soil of grasslands and wheat fields. A vision of ice sheets miles thick was replaced by a lake bigger than many seas, by broad grasslands teeming with buffalo and finally by the fenced fields, farms, towns and cities of the Canadian breadbasket.

So what do we know about the melting of the Laurentide ice sheet.

When I went looking for more specific information I found the abstract of a paper by Anders Carlson that attempts to correlate the rate of retreat of the Laurantide ice sheet with the rate of rising sea levels. Carlson did his PhD work on the dynamics of the ice sheet. He claims meltwater pulses that correllate with the relatively rapid retreat of the Laurentide ice sheet 19, 11.6 and 7.6 thousand years ago raised sea levels by 10-15, 8 and 5 meters repectively. A fourth meltwater peak 14.6 thousand years ago that raised by -- feet is not associated with obvious retreat of the Laurentide ice sheet. He says that the early part of the final event when the ice sheet lost a third of its area in 1400 years began with the opening of Hudson's Bay along a calving margin but continued once the icesheet was land based. I find the statement fairly ominous by analogy to current conditions in Antarctica even though it can be argued that the change in sea level and climate was a positive one. For instance, an interesting implication is that polar bears who make their living on sea ice and not on continental ice sheets could only have moved into the Hudson's Bay area after about 8000 years ago - about the same time that early farming communities were spreading across Europe.

An even more dramatic scenario ice loss scenario involving Hudson's Bay is suggested by Greve and Takahama. On the basis of a computer model they propose semi-periodic massive discharge of icebergs into the North Atlantic due to collapses of the ice sheet over Hudson's Bay and Hudson's Strait when base temperatures reach the pressure melting point so that very rapid basal sliding on a lubricating sediment layer develops. They propose that that the mechanism may account for layers of ice-rafted rock and debris found far and wide on the bottom of the Atlantic that were deposited in so called Heinrich Events. Heinrich events correspond to such distant effects as vegetation in Florida and rainfall in Utah. Wow! There are more than half a dozen Heinrich events known within the last 75,000 years with the most recent being at 12, and 17 thousand years ago. This is getting to be serious stuff. Who knew that the ice of Hudson's Bay was so significant?

During meltdown of the ice sheet huge fresh water lakes formed in a big arc around the southern margins. Glacial Lake Agassiz, the largest of them all was named in honour of Louis Agassiz, a contemporary of Darwin, who developed the first convincing evidence for the ice ages and popularized the concept. Lake Agassiz covered large parts of Manitoba, Western Ontario, Sakatchewan, North and South Dakota as well as Minnesota. It has been suggested that changes to drainage patterns and periodic catatrophic flooding events were important for determining ocean circulation patterns in the North Atlantic, hence acted as a major contolling factor for regional climate. When reading about the phenomena I even learned a great new word. Jokulhaup is an Icelandic word that may be destined to join gysir as the second Icelandic word to enter the English language. It means glacier burst and adds accumulations of water under glacial ice to water in glacial lakes as potential sources of flood water. Turney and Brown argue that the catastrophic draining of Lake Agassiz, presumably through Hudson's Bay about 8,000 years ago was the most drammatic flood event in the past 100,000 years. It is thought that there was enough water involved to raise global ocean levels by more than a meter. Turney speculates that this was the event that triggered the spread of agriculture across Europe as well as giving rise to the story of Noah's flood, perhaps through flooding of the Black Sea as previously suggested by Ryan and Pitman in their 1998 book.

Perhaps surprisingly, large volumes of water have been discovered under the current ice sheets. The first such discovery was lake Vostok in the center of Antarctica where the ice is at maximum thickness and drill cores have been recovered that provide an annual climate record, year by year for the past 400,000 years. Other big volumes of water are still being discovered as people now know to look for them. Water under ice sheets has raised concerns about stability of the ice and whether there are areas where it might suddenly crack and slide. Indeed there is an excellent article on the current state of the remaining ice sheets written by Robin Bell in the February 2008, edition of Scientific American magazine. The excellent article should be sobering reading for anyone who still believes that it is reaonable to stonewall, deny or treat climate change with complacency.

I was amazed at first but the discovery of water under the ice sheets does make sense when you think about it. Ice has the unusual property that it melts under pressure. It is the meltwater under the blades that makes ice skates so effective. Temperatures also increase as you dig down into the earth because of heat generated down below so one should expect the earth itself to warm the ice from below. As described by Robin Bell summer melt water also finds its way downward through cracks and crevases to help lubricate the base of ice sheets as is happening in Greenland and west Antarcica today.

So what do we know about Noah's flood and how seriously should we treat the story?

I am a thorougly secular person with a world view that is informed as well as can be by reason and science. I am therefore torn between several alternative ways to think about Noah and his flood. I do retain a deep respect and affection for the Bible as well as other sacred texts including the Koran that provide such vivid insights into human attitudes, wisdom, culture, history and conduct. As presented in Torah, Bible and Koran, Noah's story is a powerfully memorable morality tale. Until very recently it wouldnt occur to many people to doubt his message that human behavior, or misbehavior might be enough to cause a change in global climate in the form of a flood capable of destroying us all. The irony is that now that human behavior in the form of massive use of the Earth's carbon reserves as fuel has made us fully capable of causing damgerously disruptive climate change, we seem to be as hard to convince that it is important to change our ways as were the people of Noah's day.

I remember being incredulous when I first heard the story as a child in Sunday school. Where did the water come from and where did it go? How did he catch all the animals? However, I am now inclined to believe that the story is based on real events even though it may contain elements exaggerated by the art of the storyteller during preliterate times at the dawn of history before it was written in sacred texts. The story is certainly far to much fun and far to portentiously insightful to glibbly dismiss it out of hand. I am curious though about how much of the story can be relied on to provide complimentary information about real events when combined with the picture of the past being revealed by science. Is this an instance where religions and science converge to provide deeper, richer insights and a clearer warning than either could alone?

The incredible thing is that there actually was a global flood and significant extinction events associated with it although there is no evidence of any severe bottle neck in human genetics as would be implied if only one family managed to survive. For instance most of the large ice age animals of North America including giant sloth, saber toothed tigers, and mammoths disappeared forever under conditions when the world was warming. It is now clear that the water came from melting of the northern ice sheets and it never went away. The meltdown was apparantly under the influence of a subtle changes in global heat balance, a small forcing effect sustained for many years caused by the dynamics of the Earth's orbit as first described Milan Milankovich and magnified by "positive feed-back" factors. One example of a positive feed-back effect that is currently the source of much concern is directly related to the well being of the polar bears. Sea ice and snow are white with a high albedo meaning that they reflect a lot of the energy from the sun directly back out into space contributing to cooling the world. On the other hand open water has a low albedo, meaning that it absorbs much of the energy from the sun contributing to further warming as the world warms.

The scientific viewpoint is that it took about 15,000 years for sea levels to rise 400 feet before stabilizing about 5,500 years ago seems much to slow to fit with the dramma of the biblcal account. Known surges in the rate of meltdown or flow ice and water into the oceans must be considered but even these surges generally happened over time scales of more than a thousand years. Even astonishing special events like the final draining of glacial Lake Agassiz through Hudson's Bay where perhaps a meter was added to the global sea level within months seems less than Biblical. It is therefore easy to understand the tendency to want to identify drammatic local flooding events like the flooding of the Black Sea as a possible basis for Noah's story.

The flooding of the Black Sea basin must have been a totally incredible event. My personal inclination, however, is to suggest that there must have been any number highly traumatic situations where changing climate conditions and the slow but unstoppable rise in sea level, sometimes triggered by heavy rains and local flooding would force people to either move and adapt or die. Can we assume that much of the world's population then as now also lived fairly close to the sea including occupation of the deltas and flood plains of major river systems? Is it reasonable to suggest that perceptive people of the times, like Noah would notice that ancient holy places and temples near the sea were becoming more and more susceptible to annual floods, generation by generation? Perhaps there even might have been a tradition of marking flood levels on the walls of ancient temples that seemed to be slowly subsiding into the mud of the plains even as the sea moved farther and farther up the river.

It seems reasonable to infer from scriptural descriptions that Noah was a devout, influential member of a fairly sophisticated society. Furthermore his society had domestic animals and the ability to make fairly large sea going vessels and provision them for extended voyages. Ships imply maritime trade and substantial trading centers along seacoasts or coastal rivers. Is it also reasonable to believe that such a society already existed 7,400 to 9,000 years ago when the ice shelves of Hudson's Bay collapsed, when the Laurentide ice Sheet was making its final rapid retreat and when Lake Agassiz suddenly drained? There are some interesting issues here with the timeline because many historians and archaeologists would seriously doubt the existance of such a sophisticated society at such an early date. There are also people from some of the faith communities that still stongly believe that the whole world isn't even that old. However, the age of the world has been reliably established to be about 4.6 billion years based on study of the decay properties of uranium. This means that the time since the meltdown of the Laurentide Ice Sheet is a blink of the eye in terms of the age of the world but still seems to be ancient when compared with known human history.

Most authorities trace the origins of civilization, meaning the building of early cities, to the time of the Summerians of Mesopotamia and perhaps contemporaries in the Nile, Indus and Yangtse Valleys starting in the late sixth or early fifth millenium BCE and thus about 7,000 years ago. The date given for the origins of ERidu, is said to be about 4,900 BCE hence 6,900 years ago. The archaeological site identified as Eridu is known to have had mud-brick and reed buildings including raised temples and irrigation agriculture characterized by building of canals. The technical and social sophistication doesnt seem inconsistent with Noah's story even assuming Noah came from a still slightly older time. It is also noteworthy that the Summerians had a flood story of their own associated with the Legend of Gilgamesh, an early hero king who may or may not have been mythical.

When I close my eyes and give free reign to the imagination I find that it isnt a big stretch to imagine an even earlier phase of civilization pre-dating Eridu but still hidden beneath either the waves of the Persian Gulf and/or the accumulating sediments of coastal Iraq. It is known that Jerico of biblical fame was already a prosperous neolithic farming community within the appropriate time frame. Catal Hoyuk, near ---- on Turkey's Anatolian plateau is a remarkably well preserved neolithic farming community. The site has been extensively studied and provides invaluable insight into human culture and technology during what may well be Noah's time. The people were not yet using metal but did have quite beatiful pottery though made without a potters wheel. They also had baskets and woven textiles. They were growing grains including wheat and barley. Domestic sheep and goats were raised. A nearby volcano provided a plentiful supply of obsidian for making sharp stone tools. There were wild cattle and pigs in the region and domestication of these may also have been well underway. The town supported perhaps 5 to 10 thousand people so social structure must have been fairly complex. Buildings made of mud brick were built close together like a honeycomb with access through the roof using ladders. There was a small river beween two separate habitation areas and marshland round about where geese and ducks would have been plentiful at least during part of the year. I find myself imagining a wooden bridge built over the river and young men fishing. There is inevitably a strong desire to visit the place as it still exists to try to get as better feeling for how the town must have looked during the days when the place was alive with happy children, sheep, goats and industrious people.

Is it reasonable to presume that contemporaries of the farmers of Jerico and Catal Hoyuk living near the sea and thus more vulnerable to flooding might have been capable of building even bigger towns and cities as well as sea worthy ships? We know nothing about coastal towns of the day. Surprisingly, it possible to at least speculate a little about ships? I understand that there is strong evidence that the early Egyptians, Summerians etc built watercraft, both large and small by tying bundles of reeds together. One advantage is that you simply use more bundles to make bigger boats.

Thor Heyerdahl the Norwegian adventurer of Kon Tiki fame was convinced that reed boats were one of the keys to ancient oceanic exploration and trading prowess. He used pictures in Egyptian tombs plus the traditional reed boat building knowledge of people from Lake Chad in central Africa, Lake Titicaca in Bolivia and marsh lands of Iraq to build several large reed boats. Heyerdahl then tested the seaworthiness of such craft by sailing across both the Atlantic and the Indian Oceans. Reed with bitumen and wood is specifically mentioned in scripture as one of the building materials for Noah's ark.

Goodness gracious! To my considerable surprise a feasible picture is emerging that would seem to link the collapse of the ice of the Hudson's Bay region with the exploits of old Noah. Even the strange business about the flood water covering the highest peaks may have an obvious explanation. Any sailor can describe the effect of mountains apparantly dropping below the horizon as one goes out to sea. To experience waters that seem to cover the whole world anyone can simply enjoy an ocean cruise. The effect is simply because the world is round but the ancients generally didn't know that as far as we are aware at least until the time of the Greeks who sucessfully attempted to measure the diameter of the world.

We can be very sure that the waters didn't really cover the highest peaks. One of the bed-rock corner stones of modern science is the conservation of energy with mass recognized as a concentrated form of energy. There are no exceptions so massive volumes of water simply cannot be conjured out of nowhere and then disappear again.

Yes I know about the fun of finding sea shells and other marine fossils on the top of mountains. That is a whole different fascinating story featuring a time line much longer than the few thousands of years since the collapse of the Laurantide Ice Sheet and development of the roots of human civilization. The 4.6 billion year age of the our dynamic Earth as known to geologists has seen the formation and continuing drift of continents, the repeated opening and closing of oceans and the rise and fall of many mighty mountain chains. I get the feeling that all of geological time has to be pondered and understood in order to really appreciate the concept of climate, climate change and the various factors that determine global temperatures. I find it totally remarkable the thermal control factors have allowed big swings in global temperatures throughout geological time yet have managed to maintain global temperatures within the fairly narrow range where diverse life forms can grow and thrive. I do think that it should concern us all that we as human beings have been innocently, and now not so innocently, monkeying with the global thermostat. How can we now continue to believe that there will not be serious consequences?

I am obviously not the first person to make to make the suggestion that the roots of civilzation must be hidden beheath the sea. Aside from Noah, who can forget Greek legend of Atlantis sinking beneath the sea? There is a popular notion that Thera, a volcanic island in the Agean destroyed by a eruption is the basis for the Atalantis legend but it seems to me that changes in global sea level provides an attractive alternative. Graham Hancock made a provocative case for truely ancient origins of Egypt's famous sphinx - a time when the local climate was much more wet - perhaps 10,500 BCE based on orientations and sightlines to significant astronomical objects. I am intriqued that this date is even older than the time of the final surge in sea level associated with the meltdown of the continental ice around Hudson's Bay. I find that that I am not inclined to try to dismiss the astonishing claim. Indeed, it does make you wonder what fragile hints form the far past and treasures will eventually be found beneath old Cairo. Hancock has actually made a career of looking under the sea in far flung parts of the world, from Malta in the Mediteranean to the coasts of India and China, for traces of ancient roots of civilizations. His adventures and speculations are all good fun and a great read. Given the timing and complexity of the meltdown of the continental ice of Hudson's Bay I am starting to believe that eventually such traces will eventually be found.

When I close my eyes I can imagine old Noah shouting at me. "Fool" he is saying. "We only tried to save the best breeding stock from the domestic herds so we could build a new life but don't you dare let any of the animals die! I didn't know about polar bears but you do. Don't you dare let them die!"

So what is to be done? My wife and I are long time supporters of the Canadian Parks and Wilderness Society (CPAWS) but I think that I will have to take Noah's command to heart and extend support to other conservation groups as well. The World Wildlife Fund certainly deserves support for highly meritorious efforts. I would be extremely pleased if others might also be willing to also join the cause.