The earth's climate has a long history of instability versus stability. Scientists know there have been 'flips' that switch between very warm to very cold. This is obviously a concern for humans because we desire as much stability as possible. Yet many of our actions are destabilizing the planet. Climate change has caused the collapse of past civilizations and past extinctions. Variations in atmospheric chemistry and sun activity can mean great oscillations in amounts of ice versus water.
By Robert Lee Hotz, Times Staff Writer
January 5, 2007Foreshadowing potential climate chaos to come, early global warming caused unexpectedly severe and erratic temperature swings as rising levels of greenhouse gases helped transform Earth, a team led by researchers at UC Davis said Thursday.
The global transition from ice age to greenhouse 300 million years ago was marked by repeated dips and rises in the amount of carbon dioxide in the atmosphere and wild swings in temperature, with drastic effects on forests and vegetation, the researchers reported in the journal Science.
"It was a real yo-yo," said UC Davis geochemist Isabel Montanez, who led researchers from five universities and the Smithsonian Museum of Natural History in a project funded by the National Science Foundation. "Should we expect similar but faster climate behavior in the future? One has to question whether that is where we are headed."
We have to keep our eyes on the balls here: the earth's climate is again going through a 'yo-yo' for rather a while and far from humans creating this, we were created by this! If the warm cycle that created the Garden of Eden of early apes continued unchanged, we probably wouldn't exist as humans. Happily shambling about, naked, eating fruits and insects, we would be barely different from other species of our kind.
But this gentle climate so perfect for naked apes ended rather abruptly. The earth was thrown into a cycle of ice age/warm age waves that caused gross shifts in the height of the oceans, the amount of rain falling and where it fell and temperatures.
Each of these cycles had a common feature: they began and ended with amazing abruptness. The awareness of these sudden changes has only been truly appreciated in the last 50 years. The more geologists examine the actual evidence as they collect and collate data, the more obvious it is: our earth's climate is prone to severe, sudden switches.
Astronomers are wondering if this is all the fault of the earth's wobble and the sun's levels of activity or inactivity. It is hard to sort out all the influences because there is no rhythm over 3 billion years, there are long periods of stability just as there are long periods of instability.
On top of this, sorting out the influence of tectonic plate shifting makes things even more difficult. We are also not seeing things in real time but are making suppositions based on the slender amount of clues left behind in the geological records. On top of all this, the difference between a naked earth at the mercy of wind and water, is different from an earth clothed in a mantle of living things which alter the chemistry of the air, the water and the soil.
We know that every time living things burst into a new ecological niche, this changes the climate. What is interesting about the 300 million year milestone is a series of ice age/warm age cycles began, wildly, at the exact same time plants began to colonize the barren rocky lands.
&hearts We are in an unusual warm cycle right now.
BEIJING, Jan. 5 (Xinhua) -- Glaciers on the roof of the world -- China's Qinghai-Tibet Plateau -- are beating a dramatic retreat. In the past three decades, they have shrunk by 131.4 square kilometers annually, according to the latest report from the China Geological Survey Bureau.What that means is that an area of glacier equivalent to twice the size of the Beijing downtown area disappears every year.
A further 13,000 square kilometers of glacier -- nearly 28 percent of the total glacier area and equivalent to twice the area of Shanghai Municipality -- will disappear by 2050 if no protective measures are taken, the report said.
The problem with us humans is, we are a major life-form, we are physically on the large size. We are not chipmunks. Our first forays in expansion began almost instantly to change the landscape because of our hunting/gathering efforts became very thorough due to the ability to make tools. With our large brains we also began to alter the evolution of animals by making certain species dependent on us for life rather than subjecting them to the rigors of Mother Nature's brutal evolutionary rule.
As our distant ancestors realized and put into the heart of nearly all our religions, the ability to make and control fires made us into gods. This also gave us increasing power to change the entire planet in ways we little understood at that time. Yet even 100,000 years ago, the early humans realized this gave them tremendous power which is why it is considered the rupture point between being 'animals' and becoming 'gods.'
Now this ability to make fire out of the most amazing things, to generate energy that shines, we have harnessed long-dead life-forms, ancient pre-life rocks, air, wind and water as well as present life-forms. This multi-level creation of fire is of course, altering the climate of the earth just like other revolutions have in the past.
This still doesn't explain the end of the long warm period that characterized the age of mammals that followed the disastrous collapse of much of the biosphere when a meteorite struck 63 million years ago.
BEIJING, Jan. 5 (Xinhuanet) -- Recently completed research reveals warmer oceans caused by global warming is making it more difficult for eelpouts to breath and survive.Biologists have known for years declining fish stocks are connected to global warming, but a new study of eelpouts -- big-headed fish that resemble eels -- is the first to go deeper and see how warmer seas are connected to how fishes take in oxygen.
Scientists at the Alfred Wegener Institute for Polar and Marine Research in Germany studied the relationship between sea temperature and eelpouts counts in the Southern North Sea, combining data from the field with lab investigations of eelpout physiology.
The researchers not only found the oxygen levels in the waters of the North and Baltic seas have dropped because of increasing temperatures over the past 50 years -- a factor that reduces fish populations -- they also discovered eelpouts need more oxygen in warmer waters, a second factor that is reducing their numbers.
From the very beginning of life on earth, every time evolution created a revolutionary new life-form, this altered the entire biosphere. The composition of each of our cells in our bodies reflects many strange events in the furthest past as various groups of molecules tried to protect themselves from ongoing chemical changes which made survival as a free agent impossible.
As the solutions to survival created increasingly complex organisms, each of these changes altered the world outside of the organisms. If there was no change there would be no evolution. When the earth made various climatic flips, this caused evolution to jump tremendously. Namely, evolution doesn't happen because of x-rays from stars (including our own) or other cosmic rays hit the earth and cause deformations in the DNA, this is a factor giving more possibility for change, what really fuels evolution is climate change.
It is a brutal process: the creatures with the chance DNA that makes survival possible are the ones who reproduce successfully and they multiply...the others die. Today, thanks to humans, we are seeing a species die-off of historic proportions. Because of our ability to shepherd along various 'weak' species, plants and animals we have deliberately encouraged to be weaker than wild nature, we have supplanted the plants and animals which evolved within the ice age/warm age cycles of the last 2.5 million years and a terrible uniformity is now sweeping nature. This is why people aren't alarmed, really. We hear about the 'die-off' while seeing nothing odd around us. The grass is green, there are various animals about, what is wrong?
We can see it in various ways such as the uncertain weather. In the past, civilizations rose and fell on the whims of the weather.
&hearts A number of civilizations have fallen thanks to droughts, for example.
NEW research suggests that climate change led to the collapse of the most splendid imperial dynasty in China’s history and to the extinction of the Maya civilisation in Central America more than 1,000 years ago.There has never been a satisfactory explanation for the decline and fall of the Tang emperors, whose era is viewed as a highpoint of Chinese civilisation, while the disappearance of the Maya world perplexes scholars.
Now a team of scientists has found evidence that a shift in monsoons led to drought and famine in the final century of Tang power. The weather pattern may also have spelt doom for the Maya in faraway Mexico at about the same time, they say.
Both ruling hierarchies at the start of the 10th century were victims of poor rainfall and starvation among their peoples when harvests failed.
Mass migrations are also probably due to climatic change. From the very beginning, humans began to move about the planet, seeking new lands due to the fact we hate each other and try to avoid each other even as we are also attracted to each other which is why we evolved wars and complex marriage/clan rules. The Mayan and Tang cultures were able to sweep away (kill) or submerge all other clans thanks usually to some sort of war/agricultural innovation.
Then the climate changes and these innovations can become liabilities. The great migrations in the past usually were launched by climate change such as the Dark Ages, for example. The Norse sweeping out of the Scandinavian lands, for example, on raids was probably triggered by the earth cooling off only a small bit, one to three degrees!
Droughts in Northern Asia could have launched the Mongol invasions. Certainly a series of seemingly small changes in military thinking within the Mongol community, probably spurred on by the whip of climate change, allowed Ghengis Khan to rally his people into storming south, east and west seeking pasturelands and loot.
The sweeping conquests of the Europeans in the 1600's coincides with terrible climatic changes in Europe due to the Little Ice Age. Unlike trade conquests, these featured the outflow of many European farmers seeking farmlands.
Compiled by John StokesA recent scientific theory called the "hydrate hypothesis" says that historical global warming cycles have been caused by a feedback loop, where melting permafrost methane clathrates (also known as "hydrates") spur local global warming, leading to further melting of clathrates and bacterial growth.
In other words, like western Siberia, the 400 billion tons of methane in permafrost hydrate will gradually melt, and the released methane will speed the melting. The effect of even a couple of billion tons of methane being emitted into the atmosphere each year would be catastrophic.
The "hydrate hypothesis" (if validated) spells the rapid onset of runaway catastrophic global warming. In fact, you should remember this moment when you learned about this feedback loop-it is an existencial turning point in your life.
I remember when people became excited about harvesting energy from these same deposits in the deep oceans. Back in the seventies, we didn't realize the release of these deposits might change the chemistry of the atmosphere in disastrous ways. Today we realize, this is yet another thing we have to worry about.
I would suggest that as our continents shifted around the planet over the eons, as the ocean floor is squeezed between continents as they collide, the ocean floor is uplifted and this causes a disastrous release of hydrates. Since collisions usually also feature intense volcanic action, this means the world's complex climate will inevitably have such moments when the hydrates stored in the seas suddenly are released.
This still doesn't explain everything. For the sun is always and will always remain, the most important player in this game. This is why studying the Little Ice Age is so important and why so many astronomers remain very interested in that short time period. We do wonder if the gradual end to that period was not human at all but due to the sun. Just like this latest warm episode here in the north may have been due to some very strong sun spot activity during the last month.
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