working towards a better understanding of the coupled atmosphere-ocean carbon cycle.

The Carbon Cycle, The Ocean, and the Iron Hypothesis.

From the standpoint of early animal evolution, there are three possible effects of the Snowball Earth model. The first effect would occur under conditions of a prolonged frozen ocean surface and would result in a mass extinction with eukaryotic survivors being mostly terrestrial in origin (29,30). However, this type of extinction would not be seen in the terrestrial fossil record. The second possible effect is often referred to as the blue-water refugium. This hypothesis suggests that early metazoans could have survived in some kind of “larval mode” that is similar to the resistant spores that are formed by many bacteria today. However, this limited pelagic environment would not allow for the survival of phytoplankton without an active hydrological cycle. Extreme conditions in the polar regions of Earth today allow for the survival and diversification of life, mostly by life alternating between active and inactive forms. This third uniformitarian outcome may allow for a broader view to be taken on how life could survive in extreme conditions. Unfortunately, the communities seen today alternate between lifestyles during a relatively short time period (hundred, maybe thousands of years), therefore an exact comparison cannot be drawn (30).

balance , the carbon cycle the ocean and the iron ..

Zooplankton and the ocean carbon cycle.

According to the Yuga Cycle doctrine, the transitional periods between Yugas are associated with a worldwide collapse of civilizations and severe environmental catastrophes, which wipe out virtually every trace of any human civilization. The new civilization that emerges in the new Yuga is guided by a few survivors of the cataclysm, who carry with them the technical and spiritual knowledge of the previous epoch. Many ancient sources tell us of the enigmatic group of “Seven Sages” (“Saptarsi”) who are said to appear at the beginning of every Yuga and promulgate the arts of civilization. We find them in myths from across the world – in Sumeria, India, Polynesia, South America and North America. They possessed infinite wisdom and power, could travel over land and water, and took on various forms at will. Were they the survivors of the previous Yuga or visitors from outer space? Opinions differ on this point, but surely neither option can be discarded without proper scrutiny. In any case, the main point is that the transitional periods between Yugas must necessarily correlate with the severe cataclysmic events that regularly impact our planet, as reflected in the archeological records. As we shall see, the Yuga Cycle timeline proposed here correlates with these catastrophic events with a stunning accuracy. In addition, the transitional periods can also be correlated with dates recorded in various ancient calendars and traditions.

Diatoms and the Ocean Carbon Cycle ..

When investigating how ice ages begin and end, and feedbacks are considered. A positive feedback will accentuate a dynamic and a negative feedback will mute it. In the 1970s, and the author of today’s , , , which posits that Earth has provided feedbacks that maintain environmental . Under that hypothesis, environmental variables such as atmospheric and levels, levels, and Earth’s surface temperature have been kept relatively constant by a combination of geophysical, geochemical, and life processes, which have maintained Earth’s inhabitability. The homeostatic dynamics were mainly negative feedbacks. If positive feedbacks dominate, then “runaway” conditions happen. In astrophysics, are responsible for a wide range of phenomena. A runaway greenhouse effect may be responsible for . Climate scientists today are concerned that burning the hydrocarbons that fuel the industrial age . Mass extinctions are the result of Earth's becoming largely uninhabitable by the organisms existing during the extinction event. The ecosystems then collapse Mass extinction specialist recently proposed his as a direct challenge to the Gaia hypothesis.

01/01/2008 · “We need to be able to evaluate their impacts and changes to the ocean carbon cycle, ..

Ocean Iron Fertilization - SGC ..

As oxygenic photosynthesis spread through the oceans, everything that could be oxidized by oxygen was, during what is called the (“GOE”), although there may have been multiple dramatic events. The event began as long as three bya and is . The ancient carbon cycle included volcanoes spewing a number of gases into the atmosphere, including hydrogen sulfide, sulfur dioxide, and hydrogen, but carbon dioxide was particularly important. When the continents began forming, carbon dioxide was removed from the atmosphere via water capturing it, , the carbon became combined into calcium carbonate, and plate tectonics subducted the calcium carbonate in the ocean sediments into the crust, which was again released as carbon dioxide in volcanoes.

Iron ocean seeding | Feature | Education in Chemistry

When cyanobacteria began using water in photosynthesis, carbon was captured and oxygen released, which began the oxygenation of Earth's atmosphere. But the process may have not always been a story of continually increasing atmospheric oxygen. There may have been wild swings. Although the process is indirect, oxygen levels are influenced by the balance of carbon and other elements being buried in ocean sediments. If carbon is buried in sediments faster than it is introduced to the atmosphere, oxygen levels will increase. is comprised of iron and sulfur, but in the presence of oxygen, pyrite's iron combines with oxygen (and becomes iron oxide, also known as rust) and the sulfur forms sulfuric acid. Pyrite burial may have acted as the dominant oxygen source before carbon burial did. There is sulfur isotope evidence that Earth had almost no atmospheric oxygen before 2.5 bya.

To test his 'iron hypothesis', ..

In the earliest days of life on Earth, it had to solve the problems of how to reproduce, how to separate itself from its environment, how to acquire raw materials, and how to make the chemical reactions that it needed. But it was confined to those areas where it could take advantage of briefly available potential energy as . The earliest process of skimming energy from energy gradients to power life is called respiration. That earliest respiration is today called because there was virtually no free oxygen in the atmosphere or ocean in those early days. Respiration was life’s first energy cycle. A biological energy cycle begins by harvesting an energy gradient (usually by a proton crossing a membrane or, in photosynthesis, directly capturing photon energy), and the acquired energy powered chemical reactions. The cycle then proceeds in steps, and the reaction products of each step sequentially use a little more energy from the initial capture until the initial energy has been depleted and the cycle’s molecules are returned to their starting point and ready for a fresh influx of energy to repeat the cycle.