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By Julio César Centeno
All countries agree that the average temperature of the planet should not increase more than 2 ° C above the average of the pre-industrial era; that to achieve this, the concentration of CO2 in the atmosphere must not exceed 450 ppm, and that consequently global emissions must be reduced by at least 60% by mid-century. However, after years of failed attempts, the last negotiation to define an international strategy in this regard, held in Durban, South Africa in December 2011, ended in resounding failure.
The greenhouse effect It is a natural phenomenon that has allowed the development of life on earth as we know it. The natural concentration of gases in the atmosphere makes it possible to retain part of the heat energy received from the sun, keeping the temperature on the planet's surface at an average of 13.5 ° C, with significant variations mainly according to latitude, height above sea level and seasons. Without the natural balance produced by the atmospheric mantle, the temperature on earth would be similar to that of the moon, about 18 ° C below zero.
The greenhouse effect is not a threat to life on earth. But human activity tends to increase the concentration of CO2 and other gases in the atmosphere. As a consequence, it traps a greater amount of solar heat energy, raising the temperature. East global warming It has already produced an increase in average temperature of about 1 ° C, while current trends point towards a catastrophic increase between 3 ° C and 5 ° C by the end of the 21st century. A temperature 2 ° C higher than the pre-industrial age average has not been recorded on Earth in the last 300,000 years..
Global warming is the main threat facing humanity today. While public attention is focused on economic problems, on the injustice that keeps most of the world's population submerged in poverty, or on the wars for control of natural resources, global warming is accelerating in such a way that it threatens the planetary balance and the safety of all humanity.
Global warming is a direct consequence of a development model based on the growing consumption of fossil energy: oil, gas and mineral coal, fundamentally. On this platform the economies of the industrialized countries were developed and strengthened. Emerging economies and other developing countries try to emulate such processes in their struggle to improve their living standards and overcome poverty.
The consumption of fossil fuels leads to the emission of carbon dioxide (CO2) and other gases into the atmosphere. Approximately half of CO2 emissions are absorbed by the oceans, forests and soils in the first 25 years, but a third remain active in the atmosphere by the end of the first century and about 20% remain active for centuries additional. This is a cumulative process, increasing more and more the concentration in the atmosphere. CO2 currently represents three quarters of the total greenhouse gases emitted annually. Emissions of the other gases, methane, nitrous oxides and fluorocarbons, are measured in CO2 equivalent terms.
Between 1900 and 2011, 1.3 billion (millions of millions) of metric tons of CO2 just from fossil energy consumption. 72% came from countries classified today as " rich”, “ industrialized"Or" developed”. The remaining 28% came from countries “ poor", of the " Third World", Or" Developing”. However, by 2010 the industrialized countries accounted for less than 18% of the world's population. It follows that such a minority, richer, more industrialized, with greater economic and technological resources, bears most of the responsibility for the consequences facing all of humanity today.
Mainly due to these emissions, the concentration of CO2 in the atmosphere has gone from 285 parts per million (ppm) in the early 20th century, to 392 ppm in 2011, helping to increase the average temperature of the planet's surface by approximately 1 ° C.
The sea level
The rise in sea level is one of the consequences of global warming. It is due to several factors, mainly to the thermal expansion of the water volume due to its higher temperature, to the increase in the amount of water as a consequence of the melting of the polar ice masses and glaciers around the planet, and to alterations in the dynamics of terrestrial fresh water due to the reduction of the water table and the drainage of wetlands. The melting of the ice masses found in the ocean does not raise sea level as the volume remains relatively constant.
The sea level has risen 24 cm since 1875 and is getting faster and faster. In the last decade the rate of increase (3 mm / year) was approximately double that of the last century. This phenomenon occurs in parallel with the acidification of the oceans and the alteration of the seasonal cycles of the water. The oceans absorb about 85% of the excess solar radiation trapped by greenhouse gases, but because their mass is considerably greater than that of the atmosphere, their warming occurs more slowly ( POT).
According to NASA, the earth today loses 500,000 million tons of ice every year.
Between 2003 and 2010 alone, more than 2 trillion (million million) tons of ice were lost, enough to cover all of South America (17.8 million km2) with a layer 12 cm thick. Three-quarters of the thaw occurs in Greenland and Antarctica. The rest mainly in the glaciers around the planet.
Over the past 50 years, the Arctic temperature has risen at a rate more than twice the global average. In 2011 it was 2.3 ° C higher than the average for the period 1951-1980. In September 2011, the volume of ice was the lowest, while the area covered by ice was the second lowest, since there are records during this season. The area covered by sea ice in the Arctic during the month of September decreased from 8 million km2 in 1980 to 4.6 million km2 in 2011. While the volume decreased from 18 to only 5 million cubic kilometers in the same period ( NSIDC - EPI). The end of the thaw occurs in September, when the extent is the smallest each year.
There are also important losses, increasingly accelerated, in the ice masses of Antarctica. In 1994 it registered an average annual loss of 50,000 million tons, but by 2011 it exceeded 200,000 million tons of ice per year ( InSAR / RACMO2, GRACE).
The thaw has a multiplier effect on global warming, feeding itself. Ice reflects about 70% of sunlight and absorbs 30% as heat. When it melts, sunlight falls on much darker bodies of water, converting 94% to heat. As the temperature increases, the oceans emit CO2. More CO2 in the atmosphere generates more warming. This produces a dangerous spiral that amplifies global warming.
Another of the effects of global warming is the increase in the frequency and intensity of rainfall, floods, hurricanes and storms. A warmer atmosphere contains more water vapor, with its latent energy. Tropical storms in the North Atlantic have indeed increased from an average of 10 per year in the 1950s to 15 during the decade 1998-2007, with an acceleration unprecedented in the last 20 years.
The scientific evidence on the warming of the climate system is as alarming as it is unequivocal. According to National Academy of Science from the United States, " recent global warming is unprecedented in either magnitude or speed”
Already in 2005, the Academies of Science of Germany, France, the United Kingdom, the United States, Brazil, China, India, Italy, Canada, Japan and Russia issued a joint statement warning about the causes and consequences of climate change and making an urgent called on the G8 to take the lead in a global effort to confront it.
According to NASA, the last decade was the hottest in records. The 2001-2011 period includes 10 of the eleven warmest years since 1880, despite the significant reduction in solar irradiation during this period. The only year in the entire 20th century among the 11 hottest on record since 1880 is 1998.
The International Energy Agency warns in its 2011 assessment of global energy trends: “ the increase in the consumption of fossil energy leads to irreversible and potentially catastrophic climate changes ”.
The International Science Council (ICSU), representing 140 science academies from around the world, notes: “ The alarming increase in natural disasters, the growing insecurity in the supply of water and food and the loss of biodiversity are only part of the evidence that humanity is crossing planetary boundaries and approaching points of no return ”.
“ The magnitude of what we are facing vastly exceeds anything else we have faced in human history.”- Dr. P. DeMenocal, Paleoclimatologist of the Lamond-Doherty Earth Observatory.
Steve Hawking: " The danger lies in global warming becoming unstable, out of control. We need immediate action to reduce CO2 emissions”
“ A 2 ° C increase in temperature over the pre-industrial average can destroy 97% of coral reefs worldwide” – UK Met Office.
Dr. Paul Epstein, Director of the Center for the Global Environment from Harvard University: " What we projected a few years ago would happen in 2080 is happening now. We could not discern how fast and enormous the problem was, nor the magnitude with which it would affect biological processes”
“ Things are happening today that only 5 years ago seemed completely impossible, extravagant, exaggerated”- Eric Rignot, NASA.
Climate instability is no longer the exception to become the norm. If current trends remain unchanged, millions of people will be affected by heat waves, droughts, floods, storms, disease and famine; coastal cities will be threatened by rising sea levels and many ecosystems, plants and animals will be sacrificed on the altar of extinction. About 640 million people live less than 10 meters above sea level AND 150 million less than one meter (SEI 2012).
By 2011, the planet's average temperature had increased by about one degree centigrade (0.84 ° C). But the current concentration of CO2 in the atmosphere, 392 parts per million (ppm), corresponds to a considerably greater variation in temperature, even taking into account the mitigating effects of aerosol emissions or the increase in cloudiness, phenomena that help to reflect sunlight. The explanation is in the energy imbalance where the earth is today.
The planetary energy imbalance it is the difference between the energy received from the sun and that which is emitted. As less energy is emitted than is received, the planet accumulates the difference in the form of heat. NASA research indicates that the current energy retention is 0.58 watts per square meter. The total ( 300 Tera-watts) It is equivalent to 20 times the annual energy consumption of all humanity: eIn 2010 it was 15 Tera-watts.
James Hansen, Director of the Institute of Space Sciences NASA makes the following parallelism : “ The current energy imbalance is equivalent to the energy contained in 400,000 atomic bombs, such as the one dropped on Hiroshima, detonated every day, 365 days a year” ( Hansen, NASA-GISS 2012).
The difference between the maximum and minimum of solar activity is only 0.25 w / m2. The current energy imbalance far exceeds this value. The fact that it occurs just when solar activity is at its lowest is an indicator that solar activity is not the dominant factor in global warming. According to NASA, to restore the energy balance it would be necessary reduce CO2 concentration from 390 ppm to 350 ppm.
The current energy imbalance tends to be reduced through a greater accumulation of heat in the atmosphere. As the energy that is received is greater than that which is emitted, heat accumulates. As the temperature increases, the imbalance becomes less and thus tends to restore the balance. This implies that, even if CO2 emissions were stopped immediately around the world, if oil, coal and gas were suddenly stopped, if all factories, cars, planes, trains and ships were stopped , if the two-thirds of the world's electricity that currently comes from fossil fuels were to stop producing immediately, the average temperature of the planet would inevitably increase by at least an additional 0.7 ° C, to level out about 1.5 ° C above the pre-industrial era average.
The last time a similar average temperature occurred, together with a CO2 concentration above 380 ppm, was at the end of the Pleistocene, in the interglacial period Eemian, which began 130,000 years ago and spanned 12,000 years. Humanity has never known such atmospheric conditions, when the sea level exceeded between 4 and 6 meters to the current one and most of the glaciers that we have known and that we lose rapidly did not exist (GISS, NASA; IPCC). By comparison, the oldest remains of the Homo sapiens Cro-Magnon they date to only 35,000 years ago.
Unfortunately, the reality is more alarming. Emissions are growing rapidly. Only CO2 emissions from the fossil fuel consumption in 2010 they exceeded 33 Giga-tons per year and tend to increase by at least 40% by 2030, according to the International Energy Agency (IEA, 2011). In 2010 the total emissions of greenhouse gases amounted to 52 Giga-tonnes of carbon equivalents, with similar growth trends.
Despite advances in the development of alternative energies, current trends lead to an increase of 3 ° C to 5 ° C by the end of the century, promoting planetary conditions unknown to humanity, sacrificing a good part of the life forms that today we know, generating famines and unleashing climatic phenomena such as floods, droughts, hurricanes and storms with frequencies and intensities never known before.
It is urgent to deviate from current trends to lead humanity on a path of progress that allows progressively decoupling economic development from fossil fuel consumption, to base it on the use of renewable energy, free of carbon emissions. It is also urgent to stop deforestation in the short term in tropical countries, where more than 10 million hectares of forests are destroyed each year, contributing more than 6,000 million tons of CO2 to the atmosphere. It is also urgent to reverse the accumulation of CO2 in the atmosphere, through initiatives such as massive programs of tree plantations, or the capture of carbon emissions at its sources for storage in underground deposits.
Global warming is not a recent discovery, although it has taken more than a century for the enormity of its threat to be recognized, leading to a flimsy global agreement to stop it. In 1824, during the war of independence in Latin America, the French mathematician and physicist Joseph Fourier described with surprising precision the greenhouse effect, in an attempt to explain what keeps the earth's temperature in dynamic equilibrium. It was Fourier who coined the term planetary energy balance, the balance between the energy received from the sun and that which is emitted as infrared radiation (heat) into space.
Twenty years later John tyndall built a spectrophotometer to measure the heat that gases such as CO2 or ozone can absorb. He was able to demonstrate that the main gases that make up the atmosphere, such as nitrogen (78%) and oxygen (21%) are essentially transparent to both sunlight and infrared radiation. But other gases, such as CO2 and methane, were opaque: they absorbed about 95% of infrared waves, accumulating heat " like the bricks in a kitchen”. Approximately 50% of the sunlight that falls on the planet reaches the surface, to then be re-emitted in the form of infrared radiation, a form of light with a higher wavelength that we cannot see with the naked eye.
In the late 19th century, a Swedish physicist, Svante Arrhenius, expanded Tyndall's research to determine the effect of changes in the concentration of CO2 in the atmosphere on the average temperature of the planet. In 1896 he published the results of his research: if the concentration of CO2 doubles, the temperature should rise 8 ° F. A century later, the Intergovernmental Panel of Experts on Climate Change confirmed that, if the concentration of CO2 in the atmosphere doubled with respect to the average of the pre-industrial era, to reach 560 ppm, the average temperature would increase 5.4 ° F (3 ° C).
After years of negotiations, in 1992 the Framework Agreement on Climate Change of the United Nations Organization. Today, 20 years later, little progress is being made to prevent climate changes that endanger planetary security. Only CO2 emissions from fossil fuel consumption increased 57% since the agreement was signed, while the concentration in the atmosphere increased from 354 ppm to 392 ppm in the same period. Total greenhouse gas emissions reached a record high of 52 Giga-tonnes of CO2-equivalent in 2010.
The challenge facing humanity is daunting. How, then, is the astonishing inertia in international negotiations to face such a threat explained? What is the reason for the resistance of the main industrialized countries to take corrective measures, in proportion both to their respective responsibilities and to their economic and technological capacities? Why has such an obvious confrontation between industrialized and developing countries been created on this issue?
All countries agree that the average temperature of the planet should not increase more than 2 ° C above the average of the pre-industrial era; that to achieve this, the concentration of CO2 in the atmosphere should not exceed 450 ppm, and that consequently global emissions must be reduced by at least 60% by mid-century. However, after years of failed attempts, the last negotiation to define an international strategy in this regard, held in Durban, South Africa in December 2011, ended in resounding failure. It was only agreed that for 2015 such a strategy should be designed and agreed, which would go into effect in 2020.
These aspects are treated in the second part of this analysis: The Durban Suicide Deal.
Julio Cesar Centeno , Venezuelan specialist graduated from the universities of New York and Syracuse; postgraduate studies at the University of California - Berkeley. He has served as an advisor to the Secretariat of the United Nations Conference on Environment and Development [UNCED]. Executive Director of the Latin American Forest Institute. Professor at the Universidad de los Andes. Representative of Venezuela in international negotiations on forests and climate change. Invested by Prince Bernhard of Holland with the Order of the Golden Ark. Vice President of the TROPENBOS Foundation in the Netherlands. Member of the Board of Directors of the Forest Stewardship Council, FSC. Member of the Board of Directors of SGS-Forestry, Oxford. Visiting Professor at the Department of Forest Policy and Economics, University of Vienna, Austria (1999). International advisor to ITTO, BID, FAO, WB, WRI, WWF, Amazon Cooperation Treaty and other international organizations.