Saturday, March 31, 2007

Belousov-Zhabotinsky Reaction in Ecological communities self organization or chaos

The ecological communities of microflora, change rapidly to meet their changing levels of nutrients and energy. This is observable as shown by Ilya Prigorine and the Brusselator model of the BZ reaction.

A Belousov-Zhabotinsky reaction, or BZ reaction, is one of a class of reactions that serve as a classical example of non-equilibrium thermodynamics, resulting in the establishment of a nonlinear chemical oscillator. The only common element in these oscillating systems are the inclusion of bromine and an acid. The reactions are theoretically important in that they show that chemical reactions do not have to be dominated by equilibrium thermodynamic behavior. These reactions are far from equilibrium and remain so for a significant length of time. In this sense, they provide an interesting chemical model of nonequilibrium biological phenomena, and the mathematical model of the BZ reactions themselves are of theoretical interest.

An essential aspect of the BZ reaction is its so called "excitability"- under the influence of stimuli, patterns develop in what would otherwise be a perfectly quiescent medium. Some clock reactions such as Briggs-Rauscher and BZ using the chemical ruthenium bipyridyl as catalyst can be excited into self-organising activity through the influence of light.

Levich in his lectures on theoretical biology analyses Baeurs ideas on the non equilibrium of biological systems .

In "Theoretical Biology" E. Bauer confidently stated that biology was not applied physics or chemistry. He also stated that "all special laws, which would be revealed in certain fields of biology would display the general laws of motion, appropriate to living matter" [4, p.8]. The urgent problem of theoretical biology was, according to E. Bauer, the development of general laws of motion for living matter.

"Only living systems never reach equilibrium, for they constantly work against stability" [4, p.43]. According to Bauer, the source of free energy(or” the work of structuring forces" and "structural energy" are the synonyms) is the nonequilibrium of molecular structure of living matter

What is the source of the nonequilibrium of "living matter"? Firstly it is the activation of molecules of food caused by levelling processes. Energy of these molecules maintains nonequilibrium (here the molecules of living matter in "active, deformed state" are considered [4, p.127]. However, the unavoidable result of metabolism is, according to E. Bauer, the lowering of the potential of free energy of nonequilibrium. "The more intensive metabolism is, the higher rates of the free energy depletion are. This free energy of living matter exists because of the deformed nonequilibrium structure of its molecules" [4, p.129]. "During assimilation the structural energy of a system can be used. This energy is necessary for the reconstruction of nonliving substance" [4, p.144].The total amount of energy that can be assimilated is limited. This amount of energy is species-specific parameter of organism (Rubner constant) (see [4, p.131; 37] and is "proportional to the free energy of an ovicell" [4, p.130].

This means that the problem of the source of living matter's nonequilibrium cannot be reduced to the possibility of nonequilibrium's replenishment with free energy of food. Another source of nonequilibrium is required. The utilization of this source should regulate the organism's ability to make up for free energy losses with food. Concerning deeper nonequilibrium one can propose several possibilities of its origination in organism. They might be the following:

- the law of nonincrease (or conservation) of structural energy and transfer of it from generation to generation;

- the possibility of external replenishment of structural energy during the origination or fertilization of the ovicell in addition to an explanation of Bauer's theory, according to which fetal cells, possessing maximum initial potential, originate due to dying or, in other words, dissimilation of the body tissues" [4, p. 144].

- to reject the idea of the impossibility of structural energy replenishment during the life period, and then to find the ways of such replenishment, for instance, the mechanism of structural energy assimilation by autotrophs and its farther spreading in the biosphere through the food chains.

In the second and third proposals, and in other cases, allowing the structural energy replenishment, the question about the sources of such replenishment remains.
When considering the problem of understanding the stable nonequilibrium principle, another problem arises, that is the search for the sources of nonequilibrium. This problem is connected with time, its flow and becoming. One of the possible hypotheses dealing with this problem's consideration consists of the substantial time construction [28; 29].

In modeling of biological systems that oscillate from state to state seemingly random in appearance, are actually showing self organization of the ecologic community to variation of resource and both evolution and devolution.

As scientists at MIT have created an ocean model so realistic that the virtual forests of diverse microscopic plants they "sowed" have grown in population patterns that precisely mimic their real-world counterparts.

This model of the ocean is the first to reflect the vast diversity of the invisible forests living in our oceans-tiny, single-celled green plants that dominate the ocean and produce half the oxygen we breathe on Earth. And it does so in a way that is consistent with the way real-world ecosystems evolve according to the principles of natural selection.

Scientists use models such as this one to better understand the oceans' biological and chemical cycles and their role in regulating atmospheric carbon dioxide, an important greenhouse gas.

The output of the new model, the brainchild of oceanographer Mick Follows, has been tested against real-world patterns of a particular species of phytoplankton, called prochlorococcus, which dominates the plant life of some ocean regions.

Follows and co-authors report this work, part of the MIT Earth System Initiative's new Darwin Project, in the March 30 issue of Science. The Darwin Project is a new cross-disciplinary research project at MIT connecting systems biology, microbial ecology, global biogeochemical cycles and climate.

"The guiding principle of our model is that its ecosystems are allowed to self-organize as in the natural world," said Follows, a principal research scientist in MIT's Department of Earth, Atmospheric and Planetary Sciences (EAPS), lead author on the paper and creator of the model. "The fact that the phytoplankton that emerge in our model are analogous to the real phytoplankton gives us confidence in the value of our approach."

One of Follows' collaborators, Penny Chisholm, the Lee and Geraldine Martin Professor of Civil and Environmental Engineering and Biology and director of the Earth Systems Initiative, has made prochlorococcus her focus of study for 20 years. Stephanie Dutkiewicz, a research scientist in EAPS, and Scott Grant, a graduate student at the University of Hawaii, who was an MIT physics undergraduate during this project, collaborated with Chisholm and Follows on the new model.

Chisholm believes that because previous ocean models did not convey the diversity of phytoplankton, they did not well represent the systems they modeled. The new model remedies that.

"Now we are finally modeling the ocean systems in a way that is consistent with how biologists think of them-water filled with millions of diverse microbes that wax and wane in relative abundance through interactions with each other, and the environment, as dictated by natural selection," said Chisholm.

Adaptability of the Polar biosphere to changes in Irradiance

As is known high energy particles from different sources SPE ,ACR,SCR and GCR have similar photochemical effects on the ozone structure.there are still open questions concerning their effects in the atmosphere.This is seen with Gladysheva et al 2001 in analysis of the ice cores for the maunder minimum where GCR is the dominant transformer.

This of course is a big question the transfer and transformation of energy in the solar –terrestrial system and observable phenomena in the middle and lower atmosphere and the climatic oscillations.

The questions being :

The frequency,the environmental impact and the scale of catastrophic events in say geomagentic reversal where the ozone loss may be complete.

Pekka Verronen identified some of these with the complexities of the Sodankylä Ion and Neutral Chemistry Model (SIC) in studies of the short-term effects caused by SPEs.

The reconstruction of high energy events as seen here is by analysis of the nitrate levels in the ice cores. Changes to the phenotype of microbial populations in situ is another that has been overlooked.

The levels of nitrates in ice cores need to be correlated against the taxa and levels of microbial populations as amelioration (de-nitrification) has been found.The change of ratio of the carbon-nitrate-phosphorous will see changes of the taxa populations whose adapability is identified to change with nutrient levels and uv and irriadiance spectra,here the measurement is in biologic or metabolic time which is different to chronological time (age ) of the populations.

The ability of the polar biosphere both terrestrial and oceanic to rapidly adapt to changes in Uv , irriadiance spectra and radiation levels suggest that ozone depletion in the polar areas is not unusual.

In the Arctic microorganisms are not only resistant to freezing, but some can metabolize at temperatures down to -39 ºC During winter, this process could be responsible for up to 50% of annual CO2 emissions from tundra soils. Cold-tolerant microorganisms are usually also drought-tolerant. Microorganisms are tolerant of mechanical disturbance and high irradiance. Pigmentation protects organisms such as lichens from high irradiance, including UV radiation, and pigments can be present in considerable concentrations. Cyanobacteria and algae have developed a wide range of adaptive strategies that allow them to avoid, or at least minimize, UV injury. However, in contrast to higher plants, flavonoids do not act as screening compounds in algae, fungi, and lichens.As a group, microorganisms are highly adaptive, can tolerate most environmental conditions, and have short generation times that can facilitate rapid adaptation to new environments associated with changes in climate and UV-B radiation levels.

Cyanobacteria are well adapted to changeable conditions involving low and high radiation levels (including UV-B radiation), and cycles of desiccation and rehydration, increasing and decreasing salinity, and freezing and thawing. This gives them a great ecological advantage and allows them to be perennial.

In the Antarctic to date, metabolic activity has been observed in melted accretion ice at 3 °C and 1 atm (Karl et al,1999), viable microbes have been found at depth in the Vostok ice core (Abyzov et al., 1998), and microbes active at sub-zero temperatures have been reported in South Pole snow (Carpenter et al., 2000). Recent data on the isotopic composition of nitrous oxide in Vostok ice cores suggest that this gas has been biologically modified within the ice (Sowers, 2001), providing indirect evidence for active metabolism within solid ice.

The ability of microorganisms to change their spectrum of fluorescence to changes in spectra of irriadiance levels is one of the more interesting questions.

Saturday, March 24, 2007

Phytoplankton Biomass the Ecofuel powering the Pacific climate.

Phytoplankton are the “fuel” powering the climatic oscillation of the Pacific weather system. The growth phase in antiphase to the weather pattern are drivers due to the well known mechanisms of attenuation /amplification of the sea surface water temperature differentials. IE Growth and phytoplankton bloom is a priori to SST amplification,and the population decline is a priori to SST attenuation, the pacific oscillation-La Nina –El Niño.

The energy transfer pathway is Solar-heat and momentum- flux-spectral wavelengths changes and photon flux growth-pigmentation (chlorophyll)change sst change enhanced metabolic growth..

The interpretation of the population and SST variance is somewhat a chicken-egg analogy, depending on which organization analysis is used however the premis is unchanged the changes to the spectral density of the phytoplankton oscillation change the SST the level of the thermocline and atmospheric temperature gradient over the Pacific.When the phase change occurs the population reduction of zoo and phytoplankton carry the carbon to the sea floor.

The information about atmospheric warming imparts particular significance to the task of determining the real-life dynamics of the biosphere. The actual contributions of the land and ocean biotas have not been accurately determined, although there is a great body of literature on the subject.

The extensive scientific discussion of global warming causes a natural wish to relate this process to possible changes in the amount and dynamics of terrestrial and oceanic vegetation. Does this process influence variations in the amount and diversity of plants? Does it influence the pattern of their seasonal and long-term variations? It would seem that continuous elevation of CO2 and increase in the mean global temperature must cause permanent long-term changes in the amounts of phytopigments in the biosphere. But is this really so? What should be the direction of these changes?

Thus, the initial task was to reveal long-term trends of phytopigment concentrations in the ocean. This task could be fulfilled based on daily satellite measurements conducted for many years.

However, analysis of variations in phytopigment concentrations under different biogeographic conditions showed that the initial statement of the problem of studying linear or nonlinear trends was not quite correct. It has been found that on a global scale, the variations are oscillatory and the trends revealed for separate time periods must be just parts of a long-period oscillatory process. Moreover, these oscillations at different latitudes and in different times (e.g. in the time of CZCS and SeaWiFS functioning, in different seasons, etc.) are often in antiphase.

El Niño and La Niña play with the populations of microscopic ocean plants called phytoplankton. That's what scientists have found using NASA satellite data and a computer model.

The computer model showed that during El Niño periods, warm waters from the Western Pacific Ocean spread out over much of the ocean basin as upwelling weakens in the Eastern Pacific Ocean. Upwelling brings cool, nutrient-rich water from the deep ocean up to the surface. When the upwelling is weakened, there are less phytoplankton, making food more scarce for zooplankton that eat the ocean plants.

During La Niña conditions as in 1998, the opposite effect occurs as the easterly trade winds pick up and upwelling intensifies bringing nutrients like iron to the surface waters, which increases phytoplankton growth. Sometimes, the growth can take place quickly, developing into what scientists call phytoplankton "blooms."
As phytoplankton flourish during La Niña years, a large amount of carbon is used to build their cells during photosynthesis. The plants get carbon from carbon dioxide in surface waters. In the atmosphere, carbon dioxide is an important greenhouse gas. When marine organisms die, they carry carbon in their cells to the deep ocean. Surprisingly, this study found that this transfer of carbon to the deep ocean increased by a factor of eight due to the large phytoplankton blooms that can occur during a La Niña. At the same time, the effects of El Niños can reduce phytoplankton numbers, and decrease the impacts of this "biological carbon pump."

Phytoplankton alter the absorption of solar radiation, affecting upper ocean temperature and circulation. These changes, in turn, influence the atmosphere through modification of the sea surface temperature (SST). To investigate the effects of the present-day phytoplankton concentration on the atmosphere, an atmospheric general circulation model was forced by SST changes due to phytoplankton. The modified SST was obtained from ocean general circulation model runs with space- and time-varying phytoplankton abundances from Coastal Zone Color Scanner data. The atmospheric simulations indicate that phytoplankton amplify the seasonal cycle of the lowest atmospheric layer temperature. This amplification has an average magnitude of 0.3 K but may reach over 1 K locally. The surface warming in the summer is marginally larger than the cooling in the winter, so that on average annually and globally, phytoplankton warm the lowest layer by about 0.05 K. Over the ocean the surface air temperature changes closely follow the SST changes. Significant, often amplified, temperature changes also occur over land. The climatic effect of phytoplankton extends throughout the troposphere, especially in middle latitudes where increased subsidence during summer traps heat. The amplification of the seasonal cycle of air temperature strengthens tropical convection in the summer hemisphere. In the eastern tropical Pacific Ocean a decreased SST strengthens the Walker circulation and weakens the Hadley circulation. These significant atmospheric changes indicate that the radiative effects of phytoplankton should not be overlooked in studies of climate change.

In fact the energy production is around 5 times the total world consumption of energy.

Physical and biological oceanographers led by FSU Professor William Dewar put the yearly amount of chemical power stored by phytoplankton in the form of new organic matter at roughly 63 terawatts, and that's a lot of juice: Just one terawatt equals a trillion watts. In 2001, humans collectively consumed a comparatively measly 13.5 terawatts.

What's more, their study found that the marine biosphere –– the chain of sea life anchored by phytoplankton –– invests around one percent (1 terawatt) of its chemical power fortune in mechanical energy, which is manifested in the swimming motions of hungry ocean swimmers ranging from whales and fish to shrimp and krill. Those swimming motions mix the water much as cream is stirred into coffee by swiping a spoon through it.

And the sum of all that phytoplankton-fueled stirring may equal climate control.

"By interpreting existing data in a different way, we have predicted theoretically that the amount of mixing caused by ocean swimmers is comparable to the deep ocean mixing caused by the wind blowing on the ocean surface and the effects of the tides," Dewar said.

In fact, he explained, biosphere mixing appears to provide about one third the power required to bring the deep, cold waters of the world ocean to the surface, which in turn completes the ocean's conveyor belt circulation critical to the global climate system.

Friday, March 23, 2007

Solar blast from the past dwarfed modern ozone destruction

As we mentioned the most observable phenomena from the sun is during solar flares,where paradoxically,it is at its most energetic it actually causes cooling of the terrestrial climate due to ozone depletion.

As is wll known the presence of nitrates in the ice cores are a good indicator of high energy solar and cosmic ray activity,each having similar upper atmosphere mechanisms.An intersting paper published this week begs the obvious question,what if the Antarctic Ozone hole has always been present?.

A burst of protons from the Sun in 1859 destroyed several times more ozone in Earth's atmosphere than did a 1989 solar flare that was the strongest ever monitored by satellite, a new analysis finds. When energetic protons from the Sun penetrate Earth's stratosphere, they ionize and dissociate nitrogen and oxygen molecules, which then form ozone-depleting nitrogen oxides. Thomas et al. developed a scale factor between known nitrate enhancements from recent solar proton events. By using data on nitrate enhancements in Greenland ice cores following the September 1859 burst, they used the scale factor to determine that the total energy released by that solar proton event was 6.5 times larger than the amount released in the 1989 event. Models using this energy total showed that 3.5 times more ozone was destroyed in the 1859 episode than in that of 1989. Because ozone regulates the amount of harmful ultraviolet radiation reaching Earth, the authors emphasized that understanding intense solar proton events will be important to predicting potential damage to the biosphere.

Title: Modeling atmospheric effects of the September 1859 solar flare

Authors: B. C. Thomas: Department of Physics and Astronomy, Washburn University, Topeka, Kansas, U.S.A.;

C. H. Jackman: Laboratory for Atmospheres, NASA Goddard Space Flight Center, Greenbelt, Maryland, U.S.A.;

A. L. Melott: Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas, U.S.A.

Source: Geophysical Research Letters (GRL) paper 10.1029/2006GL029174, 2007

Friday, March 16, 2007

Earths thermostat the Biosphere

As we previously showed Vernadsky postulated the biosphere regulates the transformation of energy on the planet.

The Biosphere is devoted to calculations on the fraction of total solar energy used by photosynthesizing organisms to produce biomass.In the context of these calculations Vernadsky argues that it is an inherent characteristic of the biosphere that living matter is distributed on the Earth’s surface in a way that solar radiation is completely captured.In order to optimize the utilization of solar energy and to create a sufficient surface,green biomass appears in different forms in different biotopes.On land,plants have to develop three-dimensional structures in order to create a sufficiently thick film for optimal use of solar radiation.In oceans,primary production is dominated by phytoplankton because it can easily distribute over the depth of the photic zone.

Arguments against solar variance is on the basis of minimal changes to the overall energy transfer in the sun-earth coupling, however the changes are dominant in the spectra that are transformers of cellular growth i.e. the biosphere attenuation and amplification.

The total solar irradiance, or TSI, along with Earth's global average albedo, determines Earth's global average equilibrium temperature. Because of selective absorption and scattering processes in the Earth's atmosphere, different regions of the solar spectrum affect Earth's climate in distinct ways. Approximately 20 - 25 % of the TSI is absorbed by atmospheric water vapor, clouds, and ozone, by processes that are strongly wavelength dependent. Ultraviolet radiation at wavelengths below 300 nm is completely absorbed by the Earth's atmosphere and contributes the dominant energy source in the stratosphere and thermosphere, establishing the upper atmosphere's temperature, structure, composition, and dynamics. Even small variations in the Sun's radiation at these short wavelengths will lead to corresponding changes in atmospheric chemistry. Radiation at the longer visible and infrared wavelengths penetrates into the lower atmosphere, where the portion not reflected is partitioned between the troposphere and the Earth's surface, and becomes a dominant term in the global energy balance and an essential determinant of atmospheric stability and convection.

Assuming climate models include a realistic sensitivity to solar forcing, the record of solar variations implies a global surface temperature change on the order of only 0.2° C. However, global energy balance considerations may not provide the entire story. Some recent studies suggest that the cloudy lower atmosphere absorbs more visible and near infrared radiation than previously thought(25% rather than 20%), which impacts convection, clouds, and latent heating .Also, the solar ultraviolet, which varies far more than the TSI, influences stratospheric chemistry and dynamics, which in turn controls the small fraction of ultraviolet radiation that leaks through to the surface.

Vernadsky derives an expression for the “kinetic geochemical energy of living matter”. The kinetic geochemical energy of an organism is related to its mass and its speed of transmission. The latter depends on the size of the organism and the optimal number of generations per day and is normalized to the surface area of the Earth. Vernadsky frequently refers to the geochemical energy in The Biosphere especially to emphasize the enormous biogeochemical potential of microorganisms.

The interaction with and effect of solar radiation on Earth’s energy budget is strongly dependent on the electromagnetic spectrum. Planetary albedo is only relevant to short-wave radiation; hence, all far-red radiation impinging at the top of Earth’s atmosphere will either be absorbed by gases in the atmospheric column, or will be transmitted to the surface.

Some of the short-wavelength radiation impinging on the top of the atmosphere is scattered and reflected back to space,while the majority penetrates to the surface. Over 70% of Earth’s surface is covered by liquid water that absorbs about 95% of incident solar irradiance.In its upper 3 m the ocean contains the equivalent heat capacity of the entire atmosphere of the planet.As the average depth of the oceans is about 3800 m, this geophysical fluid acts as a huge heat storage system for the planet.That is,the oceans do not directly affect the radiation budget of the planet, but rather, affect the time constant by which the planet “experiences” changes in radiation.

As in the atmosphere, the direct physical interactions between solar radiation and the ocean are wavelength dependent. Water itself effectively absorbs all incident infrared solar radiation (e.g., Morel and Antoine, 1994),and this direct radiative transfer process provides roughly half of the heat to the ocean surface waters. An example of potential interactions between solar radiation and physical and biological processes is, where the following sequence is illustrated:

(1)forcing of the upper ocean physical condition through the input of solar radiation, including light, heat, and indirectly momentum at the ocean surface;

(2)upper ocean physical responses, including stratification and turbulent mixing that result in

(3) phytoplankton vertical and horizontal motions, which, in turn, lead to

(4) feedbacks on distributions of pigments and photosynthetic available radiation (PAR),

(5) modulation of the upper ocean heating via phytoplankton, and their associated
optical properties.

The balance between primary production and grazing determine the concentration of phytoplankton at any moment in time and both processes must be considered in biological–physical interactions.

The interactions among these processes occur on many time and space scales.Long-term changes (millennia to millions of years) in ocean circulation are driven by changes in radiative forcing resulting from orbital variations, albedo feedbacks, and continental configuration). Short-term changes (seconds to decades) are driven by atmospheric conditions (e.g., aerosols, cloud cover, albedo, and ozone concentration) and thermal contrasts between continents and the oceans and from the equator to the poles. Together, both long- and short-term variations in radiative transfer of broadband, as well as visible solar energy, determine the depth of the upper mixed layer, turbulent kinetic energy, and the vigor of large-scale oceanic circulation, which ultimately determines, on a global scale, the distribution and productivity of phytoplankton.

Light entering the ocean has only two possible fates; it can be absorbed or scattered. Within this context it is convenient to classify bulk optical properties of the ocean as either inherent or apparent. Inherent optical properties (IOPs) depend only on the medium and are independent of the ambient light field.

The color of the ocean is strongly influenced by suspended particulate materials, dissolved constituents, and bubbles (Kirk, 1992). The absorption and scattering cross sections of each of the components affect the spectral quality of light penetrating through the water column and the upwelling irradiance spectrum. To first order, the photosynthetic pigments of phytoplankton are the major constituents that modify open ocean color from the color blue. These pigments evolved to absorb and transform energy.

One of the clearest examples of biology affecting physical processes is the modulation of upper ocean heating rates by variability in phytoplankton and their associated pigment concentrations and related optical characteristics. Because phytoplankton absorb visible radiation in spectral regions that are relatively transparent for water itself, these photosynthetic organisms are potentially capable of altering the upper ocean heat budget. The extent to which this occurs depends on the concentration and vertical distribution of pigments within the water column, as well as the incident spectral irradiance. Intuitively, one can understand the effect by considering two bodies of water, lying side by side—swimming pools, for example. If one adds black ink to one pool while keeping the second clear, the darker pool will absorb virtually all of the incident solar radiation and become warmer faster. This effect is used to heat water in rooftop solar systems for homes. Similarly, the addition of phytoplankton to the upper ocean can have measurable effects on the rate of heating of the euphotic zone, with consequences for the depth of the upper mixed layer and vertical eddy diffusivity (e.g., Lewis et al., 1983, 1988).

Direct measurements of bio-optical as well as physical variables have been made in the warm-water pool of the western Pacific (Siegel et al., 1995; Ohlmann et al., 1998). This work is supportive of the previous assertions concerning the importance of the penetrative component of solar radiation and more generally biogeochemical processes. For example, it was determined that common values of the penetrative solar flux are about 23 W m−2 at 30 m (the climatological mean mixed layer depth), and thus a large fraction of the climatological mean net air–sea flux of about 40 W m−2. Synoptic scale forcing (e.g., wind bursts) were found to lead to tripling of phytoplankton pigment concentrations and a reduction in penetrative heat flux of 5.6 W m−2 at 30 m, or a biogeochemically mediated increase in the radiant heating rate of 0.138C/ month. In-depth analysis of the radiant heating and parameterizations of light attenuation for this experiment are given in Ohlmann et al. (1998)

Biological feedbacks cause and effect

Interesting developments in Astrobiology

In the presence of a biosphere, burial of organic carbon also contributes to atmospheric carbon sequestration in addition tosilicate weathering. The biosphere also effectively circulates carbon between its organic and inorganic states and through this process has been able to completely change the composition of the atmosphere. The early biosphere may have produced the methane greenhouse during the Archean and early Proterozoic and later, through oxygenic photosynthesis, has depleted the methane and regulated the ratios of atmospheric CO2 and O2, thus having a significant impact on the greenhouse effect of the atmosphere.

Thus the cooling of the Earth interior has slowed down mantle convection which has contributed to surface cooling due to its influence on the greenhouse effect. The brightening Sun has had an opposite effect to increase the effective temperature by 7 K from the Paleoproterozoic to the Neoproterozoic. The combined secular trend of the mean surface temperature is hard to predict and need not be large. However, both mechanisms led to the reduction of the importance of the greenhouse effect. This increased spatial and temporal temperature gradients, with corresponding increases in wind speeds and ocean currents. The climate has transformed from an early rather featureless and homogeneous greenhouse-dominated system to one containing important temperature gradients and thus exhibiting latitudinal and seasonal effects and a rich set of nonlinearities and feedbacks, among them the albedo feedback.This development would have also taken place without life, but biological effects have substantially modified it.

Saturday, March 03, 2007

Heliophysics:The New Science of the Sun-Solar System Connection

A year of scientific collaboration and public engagement events aimed at understanding space weather and the Sun's true effects throughout the Solar System starts today. The International Heliophysical Year (IHY) will begin with a ceremony held at the United Nations Science and Technology Subcommittee Session in Vienna on 19 February 2007.

The Sun connects with all the planets via the solar wind, a flow of electrically charged particles that constantly 'blows' off the Sun and creates 'space weather'. Space weather interactions can affect and erode the atmospheres of Earth and other planets, and, when channelled through a planetary magnetic field, create beautiful aurorae. Until now, physicists have been principally concerned with the way the solar wind interacts with Earth, the so-called Sun-Earth connection. Now it is time to think bigger.

"When people hear the word astronomy, I believe only five percent think of the Sun-Earth connection. Through IHY, I would like to raise that to at least ten percent," says Carine Briand, Observatoire de Paris à Meudon, and the co-chair of the European coordinating committee for IHY.

Powerful events such as the 2003 Halloween space storms obviously affect astronauts, satellites, communication and electrical power systems. But it may seem that the space environment is usually benign and unimportant because such storms are rare. In fact, the constant variation of the space environment makes the time between storms anything but calm.

Magnetic active regions on the Sun emerge and decay over days to weeks. The numbers of active regions varies regularly with the 11-year solar cycle and erratically over longer time scales - up to centuries. The patchy distribution of regions over the Sun produces variation at the 27-day solar rotation period. Many phenomena – emission of visible light, intensity of short wavelength radiation, solar wind characteristics, and blocking of galactic cosmic rays – vary significantly with the time scales of the solar magnetism, even without storms.

Light from the solar surface directly heats the Earth’s surface and lower atmosphere. Dark sunspots and bright faculae in magnetic regions alter the emission of light from the surface enough to affect the climate over long intervals.The corona above magnetic regions is heated to millions of degrees and emits strong and variable amounts of X-rays, EUV, and UV radiation. The radiation heats, dissociates, and ionizes the atmospheres of Earth and other planets, producing our ozone layer the ionosphere,and thethermosphere.It alters atmospheric chemistry and temperature, which in turn modifi es the mixing of molecules over height andlatitude. As these layers heat and cool, they become more and less dense, changing the drag that slows satellites until they reenter.

The solar wind, striking Earth’s magnetic field, drives the acceleration of energetic particles that fill the radiation belts. By contrast,Mars has no global magnetic field, and the solar wind directly impacts and strips away Mars’ upper atmosphere. The wind’s magnetic field,constantly reshaped by change on the Sun even in absence of solar events, can power intense geomagnetic storms, with the whole array of energetic particle acceleration, aurora, and disturbances of satellites systems.Coronal holes above stable solar areas power the solar wind, whichcarries magnetic fields with it. The magnetized solar wind, filling the heliosphere, deflects many of the cosmic ray particles that fill the rest of the galaxy.

Nasa Heliophsics the new science

Climate cooling Real world at odds with computer games

The important reality of climate forecasts over extended timeframes are at best an educated guess of the possibilites of the future.These are not predictions of accuracy beyond what a non scientifc prediction based on random coin tosses etc.

As Niwa says ordinary weather forecasts of conditions for a particular day cannot be usefully extended beyond about a week, because of the chaotic nature of the atmosphere. However it is now becoming clear that in some regions and under some existing climate conditions (e.g. during an El Niño) , useful predictions can be made of the likelihood of particular climatic conditions in a future month or season . (Such predictions might indicate, for example, whether the season is likely to be warmer, colder, wetter or drier than average).

Research reported in a paper by Dr John Kidson suggests that about half of the variability in New Zealand seasonal temperatures might potentially be predictable, while the remaining half is inherently unpredictable since it arises from the random, chaotic nature of the atmosphere. The scientific methods and knowledge available to us today can only reach part of the potential 50% predictability.

Mean summer temperatures were well below average. The national average temperature of 15.7°C was 0.9°C below normal and the lowest for summer since 1992/93. December was particularly cold. Summer temperatures were as much as 1.5 °C below average in quite a few eastern areas from coastal Wairarapa to North Canterbury, as well as parts of King Country and Wellington. However, summer temperatures were near average in Nelson. Rainfall was below normal in the west of the North Island from Auckland to Taranaki, as well as Eastern Bay of Plenty, and much of the north, west, and south of the South Island, with less than 50 percent (half) of normal in parts of Waikato, Marlborough, and Otago. By the end of summer severe soil moisture deficits had developed in most eastern areas of both islands from Gisborne to Otago, and spread to Auckland, Waikato, Eastern Bay of Plenty, Wanganui, Manawatu, Wellington, and Nelson. Above average summer rainfall occurred in parts of Northland and Canterbury. Sunshine hours were above normal in Northland and Westland, and below normal in South Taranaki and North Canterbury. The overall summer climate pattern was dominated by more anticyclones in the south Tasman Sea producing more frequent cool southerly winds over the whole of New Zealand. At the same time, seas around New Zealand were about 1°C below normal.

As we stated here the expertise and qualitative attributes of high energy physics is not part of climate scientists technical ability,it is not correctly assimilated into the GCM by parametization of coupled energy equations ie the models suggest closed sets with a “steady state universe in thermodynamic equilibrium”

Atmospheric scientists tend to divide the gaseous regions above a planet into two broad categories called simply lower and upper atmosphere. For Earth, the study of the lower regions (troposphere and strato-sphere) form the discipline of meteorology. The study of the upper regions (mesosphere, thermosphere, exosphere) and their ionized components (the ionosphere) form the discipline of aeronomy. The negative aspect of such a two-fold division is that it encourages thinking of the various atmospheric-spheres as isolated regions of self-contained physics, chemistry, and (in the case of Earth) biology. In reality, there is consider-able coupling from lower to upper regions, an aspect of aeronomy fully appreciated only in the last decade. Com-plimenting this external influence from below, an upper atmosphere has long been known to experience forcing and coupling to and from regions far above it. Aeronomy thus deals with one of the most highly coupled systems in space science --- with neutrals, plasmas, and electromagnetic processes that link the planets, moon, and comets from their surfaces to the solar wind and ultimately to the Sun itself.

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