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Global warming

Global warming

 Automatic translationAutomatic translation Category: ecology and environment
Updated June 01, 2013

The "macro organism" Earth is feverish and panic all humanity, each flood, storm, tsunami and other earthquake pushed the anguish of men. The effects of global warming as announced, may well be felt sooner than expected. The estimates are alarming: a warming of 1.4 to 5.8 degrees Celsius is foreseen by the end of the century, it will be the largest increase in temperature known what the Earth from about 10 000 years. In the cooler period experienced ago our planet 20 000 years and the hottest period it has known 7,000 years ago, there were only 7. If the Earth's temperature increases with a century of 5.8 degrees Celsius as announced, the living world must adapt very quickly as it has ever had to do and some species will not survive.

 

The first consequences of this warming are already visible. Indeed we see every day that glaciers are retreating, as floods are becoming more catastrophic that times of drought back more and more frequently, that the Arctic sea ice is decreasing rapidly...

Image: The magnificent Perito Moreno glacier in Patagonia (Argentina).

 glacier Perito Moreno Argentine

Energy captured by the Earth

    

Our star, the sun sends us every day a considerable amount of energy, the average annual energy is in the high layers of atmosphere, of 342 W/m2 per day. The average albedo of the Earth is 30%, about 225 W/m2/j is absorbed by soil and lower atmosphere. By comparison, all humankind consumes very little power (less than 1 / 10 000th of the energy supplied by the Sun). Solar energy comes in the form of electromagnetic radiation. These radiation we face in the form of radio waves, infrared, visible light, ultraviolet, X-ray, gamma ray. Especially in the form of visible light and infrared energy that dissipates over land but 30% of the total radiation is directly reflected back to space. The rest is consumed by our macro organism on Earth, and finally reissued in space as infrared radiation. The greenhouse gases inhibit this radiation in part to leave our atmosphere in returning those that increase the infrared temperature of the planet.

 

Image: Solar energy comes in the form of electromagnetic radiation.

 global warming
     

Greenhouse effect

    

The greenhouse effect is the phenomenon that allows sunlight and prevents the heat generated is dissipated too quickly to the outside in order to raise the temperature inside the greenhouse.
The greenhouse gases play a role in coverage because they do not prevent sunlight from reaching us, but prevent the infrared radiation emitted by the ground completely exiting into space.
The greenhouse gases are nonetheless indispensable to the balance of temperature changes because without greenhouse effect our planet would have an mean temperature of -18 ° C instead of 15 ° C at present and therefore the living world would be very different.
Humanity attends live for several years, thanks to its robots observation at a climate change accelerates.
The change in climate over time is a natural phenomenon which has pushed living beings to adapt and thus evolve gradually over millions of years.

 

Does the man may reduce the greenhouse effect to allow time to consider all the negative effects that this will lead?
It is likely, despite all our efforts, we will not change the curve started the temperature of the planet, we must reorganize and we adapt as we required whenever the "Nature".

Image: Launched on 19 October 2006, MetOp is the first satellite in polar orbit in Europe dedicated to operational meteorology.
It is the European contribution to a new joint venture with the United States, providing data to monitor climate and improve weather forecasting. MetOp is the first of a series of three satellites to be launched over 14 years, forming the space segment of EUMETSAT Polar System (EPS).

 metop ESA

CO2 carbon dioxide

    

Carbon dioxide (CO2) is the main greenhouse gases in their natural state, with water vapor.
Its lifetime in the atmosphere is about 100 years.
Releases of carbon dioxide have two origins, human From the Greek "anthropos" which means man.
Under the responsibility of man ... And natural.
Humanity has rejected in 2005, 27 gigatons of CO2 (one tone of CO2 occupies a volume of 545 m3) and the increase of these releases will increase with the strong energy needs of emerging countries.
Fires are natural even if the man has a great deal of responsibility in the number of fires on Earth.
The 1997 fires in Indonesia reached between 0.81 and 2.57 gigatons of carbon - between 13 and 40% of annual global emissions of the time.
The Ministry of Environment Canada estimated that for every acre acre is a former unit of area, 1 acre = 4046.85642 m2. burned [about 4 km2] forest predominantly composed of conifers, about 4.81 tons of carbon released into the atmosphere between 80 and 90% in the form of carbon dioxide (CO2), the remainder being carbon monoxide ( CO) and methane (CH4).
In 2006, there were 96,385 fires, representing 47.47 million tons of carbon. By way of comparison, annual emissions of carbon dioxide in the United States is around 6 billion tons.

 

Image: World production of crude oil and condensate (without gas, ethanol and other liquids which represents about 10 mb / d more).
In 2005 world production of crude oil and condensate was 73,807 mb / d in 2006 to 73,544 mbd in 2007 to 73,093 mb / d.

Image: The carbon dioxide emissions come mainly from burning fossil fuels and cement manufacturing. The Little Green Data Book 2007 indicates that this is especially true for industrialized countries and fast-growing economies like China and India.
Graphic, on forecasts of total emissions of carbon dioxide to 2030 (from data up to 2009).

 Carbon Dioxide
crude condensates

Measure warming

    

Thanks to ice cores that we remove the soil of the Antarctic, up more than 3 500 meters deep, that we read in the past.
These archives contain valuable in air bubbles trapped, the atmosphere of yesteryear. They allow us to read the Earth's climate from a remote period, up 750 000 years.
The Earth went through several major cycles of warming and global cooling during the last 400 000 years with a cycle of 100 000 years.
We are currently over 10 000 years in a cycle of warming since the last interglacial period.
It is also thanks to the many weather stations spread across the globe that we measure global warming. These are the stations that have seen rising 0.6 degrees Celsius in mean temperature of the planet since 1880.
The radio probe balloons (50 years of measurements) and meteorological satellites (since 1979) we send information about the temperatures of lower layers of the Earth's atmosphere in particular the troposphere (0-10 km).

 

The satellites do a gain of temperature between 0.05 degrees Celsius and 0.13 degrees Celsius per decade in medium layers of the troposphere, against 0.18 ° C on the surface.
Of balloons, we get a warming of the troposphere of 0.14 degrees Celsius per decade between 1979 and 2005. Or 0.4 ° C below the surface. The data from balloons and satellites are not the subject of a scientific consensus, which shows the flawed climate models.

Image: The layers of the atmosphere: it distinguishes the troposphere (0-10 km), stratosphere (10-50 km), the mesosphere (50-80 km), the thermosphere (80-500 km) and above, l'Exosphère.

 atmosphere

Greenland

    

Greenland: The Alfred Wegener Institute (AWI) in 2007 confirmed the trend of decline in sea ice in the Arctic, both in area and thickness, twice as fine as in 2001, according the results of an international expedition, conducted under the International Polar Year.
If past thirty years, fluctuations in the thickness of the ice are not regular, a trend of thinning of these layers seems to be emerging, says Dr. Ursula Schauer, head of the expedition.
Moreover, the surface of the sea ice, ocean scientists have reported the presence of melt water, they did not expect to see in such proportions.
According to the finding made and new models performed, it may be that the Arctic ice-free by summer 2070, says Dr. Schauer.

 

The shiny surface of the ice reflects into space, most of the sunlight that reaches. With the melting of ice, shiny surface decreases and a larger amount of solar radiation is absorbed, so the oceans are warming faster and it becomes more difficult for the ice to reform.
The ice is the last few decades, in a cycle where the decline is accelerating its surface.
Since the late 1970s, early satellite observations, it reached a minimum of 3 million km2, or 1 million km2 less than the minimum already observed in 2005 and 2006 (source ESA).

Image: Greenland seen from space, thinning sea ice in the Arctic.
ESA (September 2007).

 groenland space

Sahara

    

Sahara: Analysis of fossil dune formations in Chad by researchers at the CNRS in February 2006 (Science) has determined the age of the Sahara, the largest desert in the world. It would not be 86,000 years old, as we originally thought, but at least 7 million years.
According to the CNRS, there are some thousands of years, the current location of the Sahara was a humid climate and were many rivers and lakes, including Lake Mega-Chad.
The Sahara is not a young desert other desert earlier episodes were recorded, the oldest dating back 86,000 years.

 

Other clues found in cores made in the ocean off the African continent, suggest the existence in North Africa arid episodes prior to the latter.

Image: Satellite image of the largest desert on the planet, the Sahara (9 million km2).

 sahara Satellite

The Antarctic

    

Antarctica: NASA announced observing satellite early 2005 a melting ice of Antarctica on a surface area of California, a direct result of global warming, according to the U.S. space agency.
Very important areas of snow melted in west Antarctica. This cast iron, full austral summer, "is the largest observed by satellites over the past three decades. In total, the regions affected by this phenomenon cover an area as important as California, some 400,000 km2.
This phenomenon is the result of particularly high temperatures in early 2005 in this region of the globe, or 5 degrees Celsius in some places. The temperature remained positive for about a week in one of the areas observed. However, the space agency has stressed that this period did not last long enough for water to go into the ocean or gets by interstices between layers of ice, threatening to bring down huge pieces into the sea, thus raising the level.

 

The comments of JPL (Jet Propulsion Laboratory) while involved so far, Antarctica had little or no heated with the exception of the Antarctic Peninsula, said Konrad Steffen, director of research institute in environmental sciences at the University of Boulder (Colorado, West), one of the authors of the study.
Increases in temperature such as 2005, could have a significant impact on melting of ice sheets of Antarctica if they recur significantly over time, "said Steffen.

Image: Image of the Antarctic taken by the QuikScat satellite (the area is 14 million km2).

 antarctic

Ultraviolet radiation

    

Nearly 5% of the sun's energy is emitted in the form of UV radiation. Those UV rays are classified into three categories according to their wavelength: UV-A, UV-B and UV-C. However, due to the absorption of UV by ozone in the atmosphere, 99% of UV light that reaches the surface of the land belongs to the range of UV-A. UV through the atmosphere even in cold weather or cloudy (they have nothing to do with the sensation of heat provided by the sun, which is due to infrared). UV rays are reflected by water (5% UV), sand (20% UV), grass (5% UV) and especially snow (85% UV). They are more numerous between 12 and 16h and high altitude as they crossed a finer layer of the atmosphere, and are less intercepted by ozone molecules. The hole in the ozone layer is potentially dangerous because of the harmful ultraviolet important. In the upper atmosphere of Earth, the ozone layer is a concentration of ozone that filters some of the ultraviolet rays emitted by the sun. This protective layer is threatened by pollution, especially by emissions of gases CFCs (chlorofluorocarbons), which rise into the upper atmosphere and catalyze the destruction of ozone, thus giving rise to the hole in the layer of ozone. As a measuring instrument, we can see the instrument GOMOS satellite Envisat. Antonio Ruiz de Elvira, Professor of Physics at the University of Alcala de Henares (Madrid), is optimistic about the evolution of the ozone layer.

 

According to him, the hole in the ozone layer has stabilized over the past fifteen years thanks to a 90% drop in emissions of chlorofluorocarbons.
This reduction should allow the hole to close within 80 years.

ozon

Image:  Image hole in the ozone layer 24/09/2006: credit NASA

 

In 2007, the size of the hole in the ozone layer is below that of 2006, "Although the hole is smaller than usual, we can not conclude that the ozone layer is recovering already," said Ronald van der A, a specialist in the Royal Netherlands Meteorological Institute (KMNI).

ozon

Image:  Image hole in the ozone layer 18/11/2007: credit NASA

Solar activity

    

Since the 1950s, the sun has a phase of extraordinary activity. It is this conclusion reached that researchers at the Max Planck Institute for Research on Solar System, in collaboration with scientists Finnish, in an article published in the journal Physical Letters Revew. The development time of solar activity seems to follow very closely that of the mean temperature in the Earth's surface, which reflects the influence of the sun on the Earth's climate. Researchers have shown that the warming of the past 30 years can only partially be attributed to solar activity.
It follows that if solar activity affects the climate, it has played a minor role in the recent global warming. The Sun, great source of heat, allowed life to develop on our planet and guides its major climatic changes. Seen from Earth, the star looks peaceful yet it is the seat of storms and explosions of extreme violence. The European Space Observatory Soho allows specialists to have a full and uninterrupted view of the Sun.

 

They can analyze it from several angles: oscillations, electromagnetic radiation, plasma and solar wind.
The satellite collection every day thousands of images and data enable scientists to better understand the climate on a global scale.

Image:  Protuberances solar satellite views of Soho in January 2000 to May 2001. Credits: SOHO / EIT (ESA & NASA)

 activity Solar Soho

Overall ecological footprint

    

The global ecological footprint, established in the 1990s by MM. Mathis Wackernagel and William Rees, two researchers at the University of British Columbia in Vancouver, is the pressure exerted by mankind on nature. It assesses the productive surface necessary for a population to meet its consumption of resources and needs to absorb waste. This demand exceeds the limits in 2007 capacity of recovery.
The global average demand is currently 14.1 billion hectares or 2.23 hectares per person while only 1.8 global hectares of land surfaces and seas biologically productive per person. The human economy is in ecological overshoot. The overall ecological footprint of humanity has increased by 50% between 1970 and 1997, an increase of approximately 1.5% per year. The growing proliferation of the human species on the planet can cause a real environmental collapse because humanity is using water faster than it recharges in the ground. It cut forests faster than they can regenerate, emit CO2 into the atmosphere faster than it can absorb. Given the demand it is likely that in 2050, humanity consumes twice what the planet can produce natural resources.

 foot Print By Region 2007

Image: above, the ecological footprint by world region (productive area per person needed to meet its consumption of resources).

World energy demand

    

World oil demand will most likely continue to grow in the next thirty years. According to the International Energy Agency (IEA), this growth could be 60%, a forecast that remains fraught with uncertainties, as it is difficult to assess the evolution of populations, economies, ways of Life, technology and even geopolitical developments.
All forecasters agree that consumption growth will be largely driven by emerging countries like China or India, which are experiencing very strong economic growth. The application of these countries will increase three times faster than the OECD area to almost half the total demand for oil in 2030 (against 13% in 1970).

Image: tep (ton oil equivalent)

 world oil demand

Volcanism

    

All volcanic eruptions affect the climate of local and regional to some, particularly important, discharging dust into the stratosphere and altering the global climate for a few months.
Volcanic activity releases CO2 and sulfuric acid droplets form. The release of ash can reach millions of tons and rise up to several kilometers altitude causing a cooling of the climate.
In 1450 BC. JC, the volcanic eruption of Santorini in the Aegean will set suspension of such quantities of dust in the summer following in Europe and the Near East, remains hazy sky and the temperature drops about 0.5 degrees C . Recently, the eruption of Pinatubo in the Philippines in 1991 led to projections up to 35 km altitude. Two months after the explosion, more than 40% of an inter-band between 30 ° N and 20 ° S was covered by aerosols, causing a decline in average global temperature between 0.1 and 1 ° C. The Indonesian volcano Krakatoa (1883), Augun (1963, Mount Saint Helens (1980) in the U.S. and Mexican volcano El Chichón (1982) had the same effect.

 

Volcanism implies a fall in temperatures in the short term but has been a powerful factor warming at the upper Cretaceous, there are about 80 million years. The temperature was 6 ° C higher than we know today, it was the hottest period of Earth's history marked by a major volcanism.
The Krakatoa exploded in August 1883 and applies until the dust over 70 km in the atmosphere.

Image: Eruption of Krakatoa in 1997, projected volcanic dust in the atmosphere affect the Earth's climate for several years with a fall in mean temperatures of 0.25 ° C.

Image: article on volcanoes

 krakatoa

Rising waters

    

The satellite altimetry can measure accurately (of the agenda mm), changes in average global sea from the center of the Earth.
Scientists predict by 2100 the total or partial melting of glaciers, 98% of whom are currently depleted, and an average rise of sea levels between 9 and 88 centimeters.
During the last ice age, 20,000 years ago the Northern Hemisphere was partially covered by ice. The sea level was 120 meters lower than today.
With the melting of ice caps, started there 18 000 years sea levels rose gradually stabilized and then 6,000 years ago. Since then, the average level has varied only one or two meters. In one hundred years the average overall increased by 2 millimeters per year. The average rise in the overall level of the sea since 1993 is mainly caused by thermal expansion of ocean.
According to the Archimedes principle of Arctic sea ice (25 times the size of France in winter) fortunately has no impact on rising sea level.
Rising sea levels should take into account the melting of continental ice (Greenland, 10% and the Antarctic icecap, 90% of total). If the ice of Antarctica and Greenland melted completely, sea level rise by 70 meters. Since there is extremely cold, the ice did not melt because of a few degrees warmer.

 

It never fade since its formation. As against a warming would produce the opposite effect is to say that because of snowfall more abundant, the volume of ice would increase.
The main contribution of continental ice rising from the sea would be due not to Antarctica or Greenland, but glaciers mountains bordering southern Alaska, is 0.27 mm per year.
The thermal expansion of the oceans, conditioned by the fact that any liquid subjected to a warming increases the volume and the melting of continental ice are responsible for the rise in water level. The main consequences of rising flood waters will be of most lowlands, the accelerated erosion of coastal defenses and the salinization of groundwater.
According to a U.S. study, glaciers in Alaska have shrunk, for five years at a rate twice as fast as during the 40 years previous. These variations in sea level will play an important role in the evolution of life through their impact on renewals of wildlife and its adaptation (new ecological niches and migrations of populations).

 prévision WWF du niveaux des mers 

Image: The WWF 2009 report entitled "Climate feedbacks in the Arctic: global implications", provides a higher level rise of 1 meter by 2100.

Displacement of population

    

A study published in the journal Environment and Urbanization "of April 2007, identifies people facing the greatest risk because of the rising sea level and the increased intensity of hurricanes, as a result of change climate.
Research shows that 634 million people, one tenth of the world population, are located in coastal areas to 10 meters above sea level, with about 75% in Asia.
The ten countries with the largest number of people living in this area are China, India, Bangladesh, Vietnam, Indonesia, Japan, Egypt, the United States, Thailand and the Philippines.
The ten countries with the proportion of people living in this area is highest, are the Bahamas (88%), Suriname (76%), Netherlands (74%), Vietnam (55%), Guyana (55%), Bangladesh (46%), Djibouti (41%), Belize (40%), Egypt (38%) and Gambia (38%).
The authors of this study are Gordon Mc Granahan of the International Institute for Environment and Development (UK), Deborah Balk of the City University of New York and Bridget Anderson of Columbia University. The key findings of the study show that many large cities around the world who have more than 5 million people, are partly in the danger zone of 0-10 meters above the water.

 

- On average, 14% of people in developed countries live in the area of 0-10 meters.
- 21% of urban populations of less developed nations are in the area of 0-10 meters.
Again the poorest countries are most vulnerable to its effects.
Between 1994 and 2004, there were 1562 flood disasters and 98% of two million people affected by these disasters were in Asia.
Between 1990 and 2000, populations in areas of 0-10 meters of Bangladesh and China had a population growth rate twice the rest of the population.
The ten countries with the largest number of people living in this area are: China (143888000), India (63188000); Bangladesh (62524000), Vietnam (43051000); Indonesia (41610000); Japan (30477000); Egypt (25655000); the United States (22859000), Thailand (16468000) and the Philippines (13329000).
Published by Sage journals

 rainfall

Image: The rainfall triggered floods, landslides and mud from landslides that kill and forcing the evacuation of hundreds of thousands of people. In July 2007, there were more than 4,000 homes destroyed, 386 000 evacuees and dozens of deaths in the provinces of Yunnan, Chongquing, Shandong and Xinjiang.

Cyclones

    

According to the study, published in September 2007 in the journal "Science" by American scientists of the Institute of Technology, Georgia and the National Center for Atmospheric Research, the number and duration of hurricanes is generally stable for 35 years on a global scale. However, the number and proportion of hurricanes in categories 4 and 5 (the maximum level Saffir-Simpson reference) have almost doubled since 1970. This phenomenon has been observed particularly in the Pacific Northwest, the Southwest Pacific and Indian Ocean. The temperature in the tropics five ocean basins where hurricanes form, increased by 0.5 degree Celsius from 1970 to 2004. However, one of the prerequisites for the formation of a hurricane is the temperature of surface water which must be at least 26.5 ° C on at least 60 m deep. It is still difficult to assess the real impact of global warming because the strength and number of hurricanes fluctuate naturally every 20-30 years."

 

Herve Le Treut, director of research at CNRS stated on 1 September 2007 to Agence France Presse that the emergence of hurricanes like Katrina could be the consequence of global warming.
According to climatologist Kerry Emmanuel, who published a study in August 2007 in the journal "Nature", the hurricanes that hit the Atlantic and Pacific have increased in both duration and intensity by about 50% since the 1970s, but it is careful not to link this trend to global warming, particularly because the series is far too short.
The simulation models are contradictory, some finding such as a decrease in 2020 the total number of hurricanes (90 per year) in the world.

Image: Hurricane Katrina view of the International Space Station (ISS). This is the first hurricane observed in the South Atlantic Ocean near Brazil (26 March 2004). Source Wikimedia commons.

 Cyclon Catarina ISS March 26 2004

Kyoto Protocol

    

Under the Kyoto Protocol, industrialized countries have to reduce their combined emissions of six key greenhouse gases during the five-year period 2008-2012 below 1990 levels.
For many countries, achieving the Kyoto targets will be a great challenge which will require new policies and approaches.
The success of the Bonn negotiations finalized in Marrakech in November 2001 allowed the ratification of the protocol by many countries in 2002: EU and its 15 member states on May 31 2002, Japan on June 4. Finally, ratification of the Protocol by Russia on 22 October 2004 opened the way for the entry into force of the Kyoto Protocol on 16 February 2005.
It was, indeed, to enter into force, to be ratified by at least 55 countries representing 55% of CO2 emissions. Only four industrialized countries have not yet ratified the Kyoto Protocol: Australia, the United States, Liechtenstein and Monaco.

 

Australia and the United States reported that they had no intention of doing so; together, they account for more than a third of greenhouse gases in the industrialized world.
Developing countries, including Brazil, China, India and Indonesia, are also involved in the protocol but have no target for reducing emissions.

 

Expert groups

    

IPCC Intergovernmental Panel on Climate Change's mission is to evaluate how clear and objective information on scientific, technical and socio-economic which are needed to better understand the scientific basis of risk change Climate of human origin. Prevent the possible consequences of this change and consider possible adaptation strategies. Its assessments are based mainly on scientific and technical publications whose scientific value is widely recognized. More than 1,000 scientists have participated in the latest report of the group I like writers (122, selected from a large number of candidates nominated by governments), contributors (515), examiners (420) or publishers (21).

Image: http://www.ipcc.ch/

 

ONERC the National Observatory on the Effects of Global Warming was created by the Act of 19 February 2001 to inform the public and policymakers about the consequences of global warming, and to provide the Government, Parliament, elected to communities and development actors, the elements of knowledge to develop a policy of prevention and adaptation.

Image: http://onerc.org/

 

IEA the International Energy Agency is an international organization designed to facilitate coordination of energy policies of member countries. The IEA was first provided to ensure the security of energy supplies (mainly oil) to support economic growth. It now intends to accomplish this objective, while contributing to environmental protection, reflection on climate change and market reforms.

Image: http://www.iea.org/

Adaptation of ecosystems

    

Under the influence of rising temperatures, entire ecosystems are modified. Animal species as some butterflies, birds, colonize new territories, located at altitudes increasingly high, evidence of adaptation of species.
The same phenomenon was observed among representatives of the plant kingdom and many other indices betray the influence of global warming. Researchers around the Dr. Menzel found that flowering plants in North America and Europe bloom earlier, having gained 3.8 days per decade during the last fifty years.
There are the same for butterflies and birds, the first hatch 3.2 days a decade earlier, the latter argue the return of their winter quarters of 4.4 days a decade.

 

The emergence of milder winters encourage sedentary species at the expense of migrant species.
Indeed, the sedentary species, for lack of episodes of extreme cold, survive and thrive therefore more easily colonized niches migrant species during their winter absence.
Strong competition between these moves so new and old sedentary for access to resources and space for nesting.

Image: Bohemian Waxwing: migratory that feeds into winter berries. Its food needs are important, a single bird eats 2 times its weight in one day.

 Bohemian Waxwing

Amazon Basin

    

The space satellite Envisat's Advanced Along Track Scanning Radiometer (AATSR), shows the confluence of the Rio Negro and Solimões downstream of Manaus, Brazil in the Amazon basin. The Amazon, the longest and most powerful river in the world sank slowly parallel between North 5th and 20th parallel south. The river has its source in the Peruvian Andes in the west of Lake Titicaca and empties into the Atlantic Ocean at the equator after crossing Peru and Brazil. The Amazon is responsible for 18% of the total volume of freshwater discharged into the oceans of the world and its drainage network has over 1000 rivers including the Rio Negro and Solimões. The Rio Negro is named after the color of decomposed plant that carries throughout his career. The Solimões carries him on 1600 km, sand, mud and silt that its water tinged with a yellowish color. The Amazon forest is the largest virgin forest in the world. It absorbs a huge amount of carbon dioxide, conservation of the Amazon forest is one of the biggest environmental problems of the early 21st century.

 

Virgin forests disappear gradually in the world at an alarming rate while their role is vital in the global climate of the planet.

Image: Manaus is a task seen as white, raised at the confluence of two rivers black and yellow, the Amazon basin.
Picture taken on 28 September 2008 by the camera MERIS (Medium Resolution Imaging Spectrometer) Envisat high resolution (source ESA).

 envisat Rio Negro and Solimoes

Conclusion

    

It seems that scientists have great difficulty in unanimously affirming that global warming is man.
Some figures denounced the part of humankind in this warming, others show that the temperature of the planet suffers tremors in time and this is natural.
In the climate cycles of the Earth, we are in the hottest period of the interglacial curve which means that we are going towards an ice age but it is difficult to see, our time is not largely to time Geological our planet.
Yet the return of ice on the planet should arrive in several tens of thousands of years.
Since the end of the last period of glaciation there are 18 000 years, the climate is mild and relatively stable.
We are therefore in this period where there is an average of 15 degrees Celsius on the planet. Nevertheless there is a dangerously rapid rise of temperature, corroborated by the summary of the IPCC 2007 who described an increase in temperature of 0.74°Celsius over 100 years, or more than 25% higher than the increase of 0,6° C cited in its 3rd report in 2001. What is certain is that we reject more and more CO2 and other waste sickening and this is likely to continue because the energy needs of the global population increases with demographics.

 

We note at once that nature unleashed more and more violently and at the same time, that the living world is struggling to adapt to these climatic fluctuations abandoning the weakest.
It is as if our macro body "Earth is currently undergoing a small" fever ".
Just as in warm-blooded animals, his fever is a defensive reaction against internal aggression which it is obliged to activate certain immune mechanisms to regain its balance.
Only hope that these mechanisms do not fight the man as a foreign infectious agent. Humanity must now prove wise it is a constituent and not foreign planet Earth.

Video: In this accelerated video, there is a dangerously rapid rise in global temperature between 1880 and 2011.
In blue, negative anomalies (up to -2 ° C) and in red the positive anomalies (up to 2 ° C). © Nasa

 

See also

     
      
      
 
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