Friday, December 31, 2010

Lake Eyre to flood.

The Australian Bureau of Meteorology is reporting that flooding is occurring across Australia’s Queenland. The rivers that drain into the inland Lake Eyre are experiencing flooding, the rivers include; Thomson, Barcoo, and Cooper creeks.

THOMSON RIVER:

Minor flooding is easing in the Thomson River at Camoola Park, with rises and moderate flooding occurring downstream at Longreach. Minor to moderate flooding is rising downstream between Stonehenge and Jundah.

BARCOO RIVER:

Moderate flooding continues in the Alice River at Barcaldine. Minor flooding is easing in the upper Barcoo River at Blackall. River rises and major flooding is occurring along the lower Barcoo River between Coolagh and Oma where levels should peak in the next few days. Moderate to major flooding continues between Wahroongha and Retreat, with further rises expected into next week. At 9am Thursday, the river level at Retreat was 6.48 metres, which is about 4.3 metres above the Barcoo River Causeway.

COOPER CREEK:Youtube documentary

Moderate flooding is rising in the Cooper Creek at Windorah with a return to major flood levels expected in the next few days. At 3pm Thursday the creek level was 4.84 metres, which was about 0.54 metres above the level of the approaches to the Diamantina Development Road. Moderate flooding is easing downstream at Durham Downs however renewed rises and moderate flooding is expected later next week as upstream floodwaters from the Windorah area arrive.


The Lake Eyre Basin (LEB) is an unregulated system, with streamflows in the Basin being highly
variable (Puckridge et al., 1998; Knighton and Nanson, 2001). During large flood events, the LEB
rivers transform from a string of waterholes into slow moving, “inland seas” that can be as much as 60 km wide in their mid to lower reaches. Floods in these rivers are generated from rain in the upper reaches and can take months to travel to terminal wetlands or the ultimate Basin terminus of Lake Eyre North. The rivers and creeks in the region are intermittent to ephemeral, and only flow following rain periods.

Many reaches of the LEB rivers have complex flow paths with extensive
anastomosing channel systems (that is the channels bifurcate, branch and then rejoin irregularly) with greatly varying widths of active channel and floodplain. During large flood events, floodwaters can inundate thousands of square kilometres. Within the anastomosing channel system there is a complex array of waterholes, wetlands, channels and floodplains, which result in only a very small proportion of the regional rainfall arriving at Lake Eyre.

The rivers of the LEB have high ecological value and are amongst the last of the unregulated large rivers in Australia. The rivers are the foci for spectacular booms and busts in animal populations. During large flood events they support large populations of fish (Puckridge et al., 2000) and waterbirds (Kingsford, 1995; Kingsford et al., 1999) with population numbers crashing as flow ceases and surface water contracts back to the more persistent waterholes and wetlands.

Although cattle grazing, tourism and, locally, natural gas production, have had some impact on the landscape, the catchments supplying Lake Eyre are considered to be in minimally disturbed
condition. The LEB is considered significant as a result of the unusual features of the area, which
include (Morton et al., 1995):


Lake Eyre, the terminus of the Basin, is located in north-east South Australia. The lake is the fifth largest terminal lake in the world, consisting of two sections: Lake Eyre North and Lake Eyre South. The total surface area of the lake is approximately 9,690 km2, supporting a volume of 30.1 km3 (3.01x104 GL) at -9.5 AHD (see Figure 2-1; International Lake Environment Committee, undated). Originally, it was believed by European settlers that Lake Eyre North was permanently dry, however this was disproved in 1949, the first scientifically recorded filling of the lake. Since this time, numerous inflow events into Lake Eyre have been recorded, including a significant filling event that lasted several years in the mid 1970s.


Lake Eyre South is known to have filled in 1938, 1955, 1963, 1968, 1973, 1974, 1975, 1976 and
1984. In 1984 Lake Eyre South overflowed to Lake Eyre North (Hutton, 1984). In 1974 water
flowed from Lake Eyre North to Lake Eyre South between March and October when an
equilibrium level was obtained. Groyder Channel is a 15km channel that links Lake Eyre North and South. The width and bottom elevation of the channel change with each significant event.
Lake Eyre itself supports a range of flora and fauna, including emerged and submerged
macrophytes, zooplankton, algae and fish.

Ref: http://www.lebmf.gov.au/publications/pubs/hydrology.pdf

Thursday, December 30, 2010

A snipet from other areas, dealing with "Cultural Memories" within the New World


This is just a snipet of a larger article, http://firstnationschools.ca/node/157.

Native American Oral Traditions & Archaelogical Myths


While Pendergast and Meighan have clearly proven oral traditions can span hundreds of years, W.D. Strong has proven they can span thousands of years. In 1934, Strong published a convincing article detailing the Native American knowledge of the wooly mammoth. The Naskapi describe a monster they call Kátcheetokúskw (present in many of their myths) as being very large, having a big head, large ears and teeth, and a long nose with which he hit people. When presented with photos of modern elephants, the informants said they fit the description of Kátcheetokúskw as represented in their oral history. The Penobscot of Maine describe a huge animal with long teeth that leaned against certain trees to sleep (noting that when these beasts lay down, they could not get back up). The Ojibwa and Iroquois note the existence of a large beast that once ranged through the forest and was so strong that it would easily knock down any trees that stood in it's path. These "elephant" legends are rampant in many other Indigenous cultures such as the Micmac, Alabama, Koasati, and Chitimacha. (19)

In the article, Strong anticipates the onslaught of conservative anthropologists and in his concluding argument complains that, "To date, paleontologists have seemed more willing to grant recency to the mammoth than have the majority of American anthropologists to grant any geological antiquity to the American Indian." (20)

Strong's insights are very revealing as it is apparent that the rift between the Bering Strait theorists and the opposition was in place by the early date of 1934. More importantly however, if Native Americans have preserved accurate descriptions of the mammoth, they must represent an oral history going back thousands of years. In 1944, M.F. Ashley Montagu confirmed Strong's finding in an article published in American Anthropologist. The Osage of Missouri persevered a record of an incident that involved the encroachment of a herd of megafauna upon the land of the smaller animals already living there. The Osage of course incorporate supernatural beings into their account and attribute the encounter to the actions of the Great Spirit. At a certain period, many monstrous animals encroached upon the territory (along the Mississippi and Missouri rivers) of the much smaller animals already living there. The Osage were forced to abandon their homes and refrain from hunting because the gigantic animals posed a deadly threat. They remained at a sufficient distance however to witness the courageous smaller animals attack the invading monstrous animals. After a long battle, the larger animals prevailed and continued their march eastward. The Osage then burnt some of the bodies as an offering to the Great Spirit while the rest were buried in the Pomme de Terre (which was later called Big Bone river). The Osage considered this to be a sacred place thereafter and subsequently gave offerings periodically to commemorate the battle. In 1839, American settlers seized the sacred land to the great dismay of the Osage and began the construction of a tub-mill (a machine used to pound corn). After digging, the settlers discovered a mass of bones, which were identified as those of young mastodons. (21)

The fact that the Osage story correlated precisely with the findings made by the settlers is adequate evidence that the oral history of Native peoples goes back into deep time. It can thus be concluded that Native American oral history is very ancient indeed


19. W.D. Strong. "North American Indian Traditions Suggesting a Knowledge of the Mammoth." American Anthropologist 36 (1934): 81-88. Pages 81-87.

20. Ibid., Page 88.

21. M.F. Ashley Montagu. "An Indian Tradition Relating to the Mastodon." American Anthropologist 46 (1944): 568-71. Pages 568-71

Wednesday, December 29, 2010

Thoughts on Terraforming Venus or Mars.


Figure 1: Left: Earth with oceans and atmosphere represented as spheres (Ice-blue, atmosphere; Cyan-blue, water/oceans). Right Center: Venus with atmosphere; Far Right: Ceres compared to Earth and Venus in 50 kilometers per pixel.

In the above image, on the left, the radius of Earth = 6378000 m so volume of Earth = 1.08678129 × 10^21 m^3. Average depth of ocean over 3/4 of Earth's surface = 3800 m so it over the whole surface it would form a hollow sphere 2850 m thick. Subtract Earth's volume from that of the larger sphere to get a volume for the water of 1.45753101 × 10^18 m^3. The radius of a sphere of that volume would be 703358 m, a little over 1/10th the radius of the planet, and represented by the clear cyan blue sphere. The adjacent ice-blue sphere represents the volume of the atmosphere. The Hydrosphere is the layer of water which covers about 71% of the earth's surface. The average depth of the oceans is 3794 m (12,447 ft), more than five times the average height of the continents. The mass of the oceans is approximately 1.35 quintillion (1.35 × 10^18) metric tons.

The center right image is that of Venus, that was taken by the European Space Agency orbiter Venus Express. With Earth and Venus approximately the same size, and having formed at the same time, astronomers believe that both planets likely began with similar amounts of water due to comets during the Late Heavy Bombardment that ended 3.9 Billion years ago. However, Anabar (2009) et.al, page 4, indicates: “by contrast there appear to be no surfaces on Venus that date back to the early bombardment.” The presentation of Sizemore (2004) that “Venus has undergone a catastrophic, global resurfacing event in recent geological history” that apparently “ended 700-800 Million years ago” and due to a global recycling of the planetary crust because of volcanism.

Despite Venus being called Earth's "twin", its surface conditions are far from being alike to our home planet's. Venus's surface is surrounded by a thick mass of clouds. The atmosphere of Venus is heavier than the atmosphere of any other planet. It is made up of carbon dioxide, small amounts of nitrogen and water vapor, and very little portions of argon, neon, sulfur dioxide, and carbon monoxide. The atmospheric pressure on Venus is about ninety times more than it is on Earth. It is about 1,323 pounds per square inch. If one were to stand on Venus, the atmospheric pressure would crush you within seconds. The surface of Venus is very hot and dry. Moreover, there is no liquid water because it would boil away from the heat. Most of Venus (65%) is covered by flat plains, where there are thousands of volcanoes. Thirty-five percent of Venus is made up of mountains. The highest is Maxwell, which is seven miles high. There is also a canyon that is .6 of a mile deep. Another feature of Venus is impact craters, which are formed from an asteroid and a planet crashing. There are two large highland areas: Ishtar Terra and Aphrodite Terra. Coronae, another characteristic of Venus, are circular volcanic structures surrounded by ridges, grooves, and lines. Arachnoids are another unique feature to Venus. Arachnoids are circular and oval features with concentric rings and a group of fractures

As Venus and the Earth are comparable in size, the inclusion of the atmosphere within the image would be representative of the Earth with an atmosphere (which is confined in the ice-blue sphere on the left side of the image and above the Earth). Directly to the right of Venus, the grey sphere represents Ceres. The Planetary Society presents a topic on Ceres and the aspects of a potential “ocean” by stating:

Exactly where the layers lie inside Ceres depends on how much ice it contains, which depends on how dense its rocky component is. If Ceres is less icy, it has a relatively thin water ice layer of about 70 kilometers (45 miles) in thickness; if Ceres is more icy, its ice layer would be about 120 kilometers (75 miles) thick.

There is an excellent image of Venus with oceans that was created by in Australia with a few interesting concepts of how the planet might look.

It is widely accepted that the current dryness of the Venus atmosphere is the result of extensive evolutionary processes. The amount of carbon in the form of CO2 in the Venusian atmosphere is comparable to the best estimates of the Earth’s carbon inventory, which is largely locked up in carbonate rocks. This finding suggests that a “runaway” greenhouse scenario led to the lack of plate tectonics and biogeochemical cycling on Venus. According to this hypothesis, the primordial inventories of volatile elements on Venus and the Earth were similar (on a mass-adjusted basis); the present differences in distribution between atmosphere and lithosphere are evolved.

If so, the extreme scarcity of H2O in Venus’ atmosphere could be a consequence of photolysis of primordial H2O followed by loss of H to space, possibly within the first billion years. The high D/H ratio of the Venus atmosphere supports this hypothesis, but this interpretation is complicated by the fact that volatiles can be accreted long after formation – even in the geologically recent past – in the form of cometary impacts, and by uncertainties in the D and H escape fluxes. Hence, the D/H observations could alternatively be a result of H2O escape and resupply in the last billion years.

Since the average depth of the oceans is 3794 m (12,447 ft) on the Earth, roughly equivalent to 2.4 miles deep. The water layer proposed for Ceres, while smaller in circumference, is many miles thicker. The total volume of water on Earth is about 1.4 billion cubic kilometers, around 41 million of which is fresh water. If Ceres' mantle accounts for 25 percent of the asteroid's mass, that would translate to an upper limit of 200 million cubic kilometers of water.

If Ceres could eventually be destabilized from the current orbit and impact Venus, the resulting ocean depth would range 1/7 of that on the Earth or 542 m. Unfortunately, due to the pressure and the temperatures the water would become vapor and would remain in the upper atmosphere and then the hydrogen would be stripped by the solar wind and lost to space.

It would take approximately 10-20 Ceres size objects diverted to Venus to recreate enough water vapor in the atmosphere before atmospheric destabilization occurred with rain starting to fall on the high upland mountains. If smaller comets were diverted or Kuipler Belt objects were brought into the inner solar system, then a much larger number >10,000 would be required. A series of impacts, might assist in the removal of a significant part of the current atmosphere by blasting it into space. This would facilitate lower atmospheric pressures from the current atmosphere pressure to a lower.

NOTE: The future is a unknown progression of humanity and development of technology and innovations, maybe over the next 900 years humanity might decide that Terra-forming could occur. How orbital dynamics of Ceres could be change and the technology involved is the decisions of the future generations of humanity. Maybe, Ceres could impact Mars, given the amount of water that exist on Mars and on Ceres a planetary impact would create something on the order of magnitude of a Hellas Impact basin and liberate the water from both Mars or Ceres to form a northern ocean. With terrain being ejected material from the impact event and that might create enough heat to start the convection within the mantel and subsequent magnetosphere on Mars. This is a thought exercise and conceptual idea, a seed in the garden for the future generations of humanity and the unknown technologies that occurs hereafter.

Bibliography

Anbar, A. D. (2009) et. al. Astrobiology Research Priorities for Mercury, Venus, Earth, and the Moon. A White Paper for the 2009-2011 Planetary Science Decadel Survey . Arizona State University.