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JUST LIKE A GLASS BOWL - Radiation from the sun would be reflected out into space, but with more greenhouse gases in the atmosphere some radiated heat is absorbed and re-emitted back to earth just as if we lived in a greenhouse.
The greenhouse effect is the process by which absorption and emission of infrared radiation by gases in a planet's atmosphere warm its lower atmosphere and surface.
It was proposed by Joseph Fourier in 1824, discovered in 1860 by John Tyndall, was first investigated quantitatively by Svante Arrhenius in 1896, and the hypothesis was reported in the popular press as early as 1912. The scientific description of global warming was further developed in the 1930s through 1960s by Guy Stewart Callendar.
Without the Earth's atmosphere, the Earth's average temperature would be well below the freezing temperature of water, when life on Earth would cease. Hence, we need our envelope of gas to live, but not so much of a warm layer that we boil. The ocean and ice caps acts like a giant heat sink, absorbing 20 times more heat than the atmosphere.
The major greenhouse gases are water vapour, which causes about 36–70% of the greenhouse effect; carbon dioxide (CO2), which causes 9–26%; methane (CH4), which causes 4–9%; nitrous oxide that accounts for around 5.6% and ozone (O3), which causes 3–7%.
THE DETAILS - Apart from CO2, CO4 and N2O, we have hydroflourocarbons, perflourocarbons and sulfur hexaflouride (HFC's, PFC's & SF6). It's a complicated gas soup with water vapour featuring prominently in the mix - something we cannot do much about. We can only deal with man-made gases.
Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere, leading to increased radiative forcing from CO2, methane, tropospheric ozone, CFCs, and nitrous oxide.
According to work published in 2007, the concentrations of CO2 and methane had increased by 36% and 148% respectively since
1750. These levels are much higher than at any time during the last 800,000 years, the period for which reliable data has been extracted from ice cores. Less direct geological evidence indicates that CO2 values higher than this were last seen about 20 million years ago.
There are efforts to develop types of cement that produce less CO2 but it is feared not enough is being done. Estimates of global CO2 emissions in 2011 from fossil fuel combustion, including cement production and gas flaring, was 34.8 billion tonnes (9.5 ± 0.5 PgC), an increase of 54% above emissions in 1990. Coal burning was responsible for 43% of the total emissions, oil 34%, gas 18%, cement 4.9% and gas flaring 0.7%.
THE CAUSES IN SECTORS - Transportation and energy for living are the main causes of greenhouse gas build up in the atmosphere as carbon dioxide and nitrous oxides, with agriculture loading us with methane and more nitrous oxides. Hence, we need to revise our eating habits and switch to renewable energy for our cars and industry as quickly as possible.
In May 2013, it was reported that readings for CO2 taken at the world's primary benchmark site in Mauna Loa surpassed 400 ppm. According to professor Brian Hoskins, this is likely the first time CO2 levels have been this high for about 4.5 million years. Monthly global CO2 concentrations exceeded 400 ppm in March 2015, probably for the first time in several million years.
On 12 November 2015, NASA scientists reported that human-made carbon dioxide continues to increase above levels not seen in hundreds of thousands of years; currently, about half of the carbon dioxide released from the burning of fossil fuels is not absorbed by vegetation and the oceans and remains in the atmosphere.
Over the last three decades of the twentieth century, gross domestic product per capita and population growth were the main drivers of increases in greenhouse gas emissions. CO2 emissions are continuing to rise due to the burning of fossil fuels and land-use change. Emissions can be attributed to different regions. Attributions of emissions due to land-use change are subject to considerable uncertainty.
Emissions scenarios, estimates of changes in future emission levels of greenhouse gases, have been projected that depend upon uncertain economic, sociological, technological, and natural developments. In most scenarios, emissions continue to rise over the century, while in a few, emissions are reduced.
Fossil fuel reserves are abundant, and will not limit carbon emissions in the 21st century. Emission scenarios, combined with modelling of the carbon cycle, have been used to produce estimates of how atmospheric concentrations of greenhouse gases might change in the future. Using the six IPCC SRES "marker" scenarios, models suggest that by the year 2100, the atmospheric concentration of CO2 could range between 541 and 970 ppm.
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THE BLONDE YEARS - Business success does not appear to go hand-in-glove with conservation needs, where there is no profit in doing the right thing, other than saving the planet. But you cannot bank saving the planet. This begs the question, do we want hard nosed business ethics entering the political arena with Presidents like Donald Trump. Want it or not the USA have got it because he used his climate change dollars to buy the presidency. Should that be allowed? We'd suggest a cap on allowable election expenses. We live in hope that the entrepreneur might develop a conscience while still in office.
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