Little Ice Age
From Wikipedia, the free encyclopedia

The Little Ice Age (LIA) was a period of cooling occurring after a warmer era known as the Medieval climate optimum. Climatologists and historians find it difficult to agree on either the start or end dates of this period. Some confine the Little Ice Age to approximately the 16th to the mid-19th centuries. It is generally agreed that there were three minima, beginning about 1650, about 1770, and 1850, each separated by slight warming intervals.

Northern hemisphere

The Little Ice Age brought bitterly cold winters to many parts of the world, but is most thoroughly documented in Europe and North America. In the mid-17th century, glaciers in the Swiss Alps advanced, gradually engulfing farms and crushing entire villages. The River Thames and the canals and rivers of the Netherlands often froze over during the winter, and people skated and even held frost fairs on the ice.

Southern hemisphere

An ocean sediment core from the eastern Bransfield Basin, Antarctic Peninsula shows centennial events that the authors link to the Little Ice Age and Medieval Warm Period

In 1836, snow fell in the city centre of Sydney, Australia, the only time since European settlement in 1788 that this has occurred.

Tropical Pacific coral records indicate the most frequent, intense El Niño-Southern Oscillation activity occurred in the mid-17th century, during the Little Ice Age

Climate patterns

In the North Atlantic, sediments accumulated since the end of the last ice age nearly 12,000 years ago show regular increases in the amount of coarse sediment grains deposited from icebergs melting in the now open ocean, indicating a series of 1-2°C (2-4°F) cooling events recurring every 1,500 years or so. The most recent of these cooling events was the Little Ice Age.

Causes

Scientists have identified two causes of the Little Ice Age from outside the ocean/atmosphere/land systems: decreased solar activity and increased volcanic activity. Throughout the Little Ice Age, the world also experienced heightened volcanic activity.[21] When a volcano erupts, its ash reaches high into the atmosphere and can spread to cover the whole of Earth. This ash cloud blocks out some of the incoming solar radiation, leading to worldwide cooling that can last up to two years after an eruption.

End of Little Ice Age

Beginning around 1850, the climate began warming and the Little Ice Age ended. Mainstream scientific opinion on climate change is that warming over the last 50 years is caused primarily by the increased proportion of CO2 in the atmosphere caused by human activity.

Hmmmmm...Sounds like our civilization saved us from the Ice Age caused by 'natural phenomina!' The earth left on its own would kill all life over time...

Believe it or not. I've actually been doing a bit of research on this very topic, and how it plays against our current "global warming" issues we hear so much about.

What I've found.... Average cycle is approxiamatly 10 - 15,000 years. Usually an Ice Age is preceded by a "global warming" effect. Scientist within this field say we are overdue for an Ice Age.

Magnetic Polar shifts also occur during these periods of heating up/cooling down. Something scientist say is occuring as we speak....slowly.

The heating up part, causes the cooling effect due to the ocean streams inability to circulate properly/completely, as in the past.

Galactic Equinox......I haven't found enough information to place the cycle within the perimeters as of yet. But I am looking.


The Japanese were/are fanatical about keeping records on Cherry Blossom Blooms;

Japanese Cherry blossom cycles do show a marked increase within the last 20 years of the temps. Many are directly related to urban "heat" factories we call cities. But others (outside the city) show a 2 week differance in time of blooms. Meaning there is a marked increase in temperature. Japanese historical records go back prior to the 1600's New records have been found as old as 1400. They are currently being translated for the scientific community. For research purposes of course. These are a ***** to find, so be patiant if you want to look at these charts.

Washington DC trees have shown a 2 week shift in bloom dates/patterns also....since planting.

A fact that I have not seen published by anyone. I remember as a child in the 70's, hunting on Thanksgiving Day....in a t-shirt and shorts. This was long before the "90's" disaster of "Global Warming". I've never had the oppurtunity to do it since. It's been too **** cold. That said...that same year our pond froze hard enough to skate on....in Mississippi.

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I have no buckets. So please tell me how I'm supposed to bail you out?

For almost 150 years citrus has been grown in this valley. And "freeze" years, meaning years in which we freeze hard enough, long enough, to damage the fruit have only happened every 20 years or so, until 1990. In 1990 the hardest freeze ever recorded here occured between Dec 24th, and Jan 2, 1991. (Merry Christmas to us!) They are now occuring in regular 6-8 year intervals.

The rainfall pattern here is changing, and summers are getting hotter. Until just the last part of August, it had been several years since we had seen a summer thunderstorm.

Bonnie

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Tracking weather patterns is an offhand hobby I have. I use them for hunting. I watch the current map every morning I hunt, to decide on which stand to hunt out of.

I used to could put these stands up in predictable positions. When a low pressure system moved in, the wind was always from the south. We got whatever rain hit Houston, TX

That is no longer the case. Rain in Houston, continues north, or moves west...no longer does it come northeast. Winds now come from the east northeast in a low pressure system.

Notably, storm systems as you may have noticed with the current hurricanes are tracking further south and west this year. Of course this may change next year LOL.

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I have no buckets. So please tell me how I'm supposed to bail you out?

There does not seem to be any logic or rule governing the planet’s behavior.

It is not only the direction but also the strength of this magnetic field that is a concern. In the time of dinosaurs, at an estimated 2.5 gauss, it was eighty percent stronger than it is now. This may have been one of the reasons such gigantic life forms thrived. It is now accepted that a catastrophic event ended the reign of giant reptiles. However, they did not re-evolve to equivalent dimensions. And the disappearance of mammalian “mega-fauna” in more recent times is still considered to be a mystery. The mastodons and mammoths would have towered over modern elephants. Why are there so few large terrestrial animals today?

The smaller average size of modern animals may be due to the gradual decline of Earth's "steady state" (as opposed to “pulsed”) magnetism. Thousands of years ago the Chinese, with their astute discovery of bio-electrical energy flows known as “meridians”, learned that magnetism promotes vigor in biological life. They used magnetic rocks in medical treatment. In the past century there has been a further decline of earth's magnetic field by another five percent down to only 0.5 gauss. This has led Dr. Dean Bonlie to identify a "magnetic deficiency syndrome" resulting from the biological stress caused by the weakening of this "energy base" for life

The weakening of earth’s magnetism is one of the factors believed to be predictive of a pole reversal. That magnetic field reversals have occurred in the past is confirmed in the geological record. What is unclear is how precisely the transition occurs, and what happens to life forms extant at the time of this pole flip.

Does the magnetic field drop to zero gauss? Dire predictions follow upon the heels of this theory. Electronic devices would all be at risk: there may be damage to, or complete loss of, all near-earth-orbiting satellites and possibly the space station itself. Effects on life forms could range from migrating birds losing their sense of direction to immune system decline and even widespread die-off from radiation-induced cancers.

Losing its protective magnetic envelope, the atmosphere would expand and become thinner, possibly leading to altitude sickness near sea level. No longer filtered out, deadly cosmic rays would kill most if, not all, living creatures on the surface. Only those living in deep caves would be safe. This scenario has prompted some to build underground bunkers in hopes of surviving.

Countering this frightening vision, NASA predicts that, rather than declining to zero gauss, the magnetic field would become disordered. Thus we might for short time have more than one north and south pole on the planet. This official scientific stance says that the magnetosphere which shields us from cosmic radiation would not entirely disappear either. Thus, while communications would be erratic and perhaps at times completely inactivated, humans would find ways to survive. However, there are dissenters in the ranks, pointing to the vast South Atlantic magnetic anomaly and radiation damage to satellites over that region attributed to weakening of the protective magnetosphere.

The disorderly-flip theory is supported by evidence from geology that in past reversals the decline was not total. Lava flows that solidified at Steen's Mountain during a lengthy reversal process show that the magnetic poles wandered across the equator three times. Though strength of the field was reduced to about 20% of maximum, there is no record that it fell to zero gauss during that transitional period.

The theory that activity in the turbulent molten outer iron core of the planet generates its magnetic field currently dominates scientific thinking. Stormy activity deep in the earth's outer core, believed to be filled with roiling convection flows of molten iron, is understood to generate the planet’s magnetic field. Such violent seething could affect the mantle as well, possibly disturbing the earth's crust and causing the quakes.

However, there is an alternate theory of how the magnetic field is generated. In his article, "Origin of the Earth's Magnetic Field", Ernest McFarlane outlines gaps in the molten-iron convection theory. He proposes a system of electronic cells in a crystalline metal core with hot spots of heavy metals releasing alpha and beta particles. Due to the high heat the alpha particles are unable to combine with the free electrons. "Consequently an electron current flow is produced and conditions are set up for the generation of current loops throughout the inner and outer core. ... magnetic fields are produced as a consequence, in accordance with the right hand rule of electromagnetic theory."

Which theory is right? We may find out from experience sooner than we can come to amicable agreement, given the conflicting theories and computer models. The actual dynamics may include aspects of both, or new insights not yet fully developed.

The sun reverses its magnetic field like clockwork every eleven years at the peak of the sunspot cycle. The next solar flip is due in 2012. South-pointing magnetic flux moves from sunspots, which are intense magnetic loops near the equator of the sun, along “meridional flows” to the north magnetic pole, and vice versa. As the oppositely-directed charge accumulates at the poles the field declines, until eventually the reverse charge predominates.

Scientists point out that the heliosphere does not wink out of existence during this reversal. The sunspots are intense magnetic knots, much stronger than the star’s main field, which continue to spiral outward even when the main dipole field vanishes briefly. Though the solar magnetic reversal is not completely understood, the Ulysses space probe has sent back detailed data which has supplied answers to many questions.

The mechanism that controls earth's field reversals may not be based on similar principles. For one thing, a planet does not seem to have any equivalent to the powerful sunspots. McFarlane refers to there being more than one north-south pole system and about 10% of the total field being involved in smaller extra fields. If these subordinate minor magnetic fields take up more of the magnetic activity during the main field’s decline, they might become active enough to sustain a minimal protective layer shielding the biosphere, even if the main dipole field declines to zero gauss. This could be important for our survival, as the Steen’s mountain lava flows indicate that the reversal took 4,500 years to be completed!

IMPLICATIONS FOR HUMANITY’S ENERGY NEEDS

Whether the magnetic field is primarily molten-metal flow dynamics or electron current loops, or a combination of those and other factors, a magnetic pole reversal may be of significance to the search for clean energy generation and transportation. If earth magnetic anomalies become more frequent or are concentrated in certain areas, we could see disruption of existing electrical grids, even without the dramatic atmosphere expansion and radiation damaging to life and computers.

Sorry, have to say this!

EVERYBODY HIDE!! MOTHER NATURE HAS PMS!!!

Bonnie

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Ohhhhhhhhhhhh Jam! It's in the book of Job somewhere about the first Ice Age. I forgot where it is and am too lazy to look right now.

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"Tude"

" A good attitude will get you through almost anything"

Summary of Discovery Programs about Earth Formation

They ran a series of programs on yesterday (Sunday) about the formation of the earth. Showing how the 'age' of the earth was calculated (over the centuries to present) at 4.5 Billions years old, and the many 'gyrations' it went thru to become what it is today! The earth is a 'conglomeration' of meteors & comets that was a viscous ball which eventually cooled when nuclear reactions (similar to the sun's) ceased. That decay of nuclear reactions turned into lead and thereby we get into carbon dating.

They showed a piece of a meteorite that was 5% water composition!? Never heard that one, but know that the theory is that comets provided all the water on earth to date. A vapor canopy built up and then collapsed (sounds like scriptures at Noah's time!) and it rained for the first time for 'millions of years' to produce the oceans---of which the earth was covered up to 90% in water.

What really intrigued me was that life really didnt 'team' until about 250 million years ago when the earth could actually be habitable. And that there have been 'many' ice ages thru out that period (about every 50-100k years) , and it just so happens that modern man (being around about 50K years) happened to 'enjoy' the latest 'warmup period' . According to the program, we are headed back to another ice age in that cycle of cold/hot!!!

So, let's hear it for 'global warming'---yeah!! Man may have 'bumbled' into saving this planet by being here in large numbers, or at least slowing down the cycle...

I guess I will just have to keep my winter coat handy. Jam, this is scary and facinating. I wish I could keep up with everything you are saying, but I am learning!

Thank you!

Bonnie

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