Scientists at University of Toronto discovered a long-lived manmade greenhouse gas (GHG) called Perfluorotributylamine (PFTBA) that is 7100 times more potent than carbon dioxide at warming the Earth over a 100-year time span.
The new discovered gas PFTBA which does not occur naturally has been in use in the electrical industry such as transistors and capacitors since the mid-20th century. It belongs to an entire class of chemicals used for industrial applications whose effects on the atmosphere remain unknown.
Concentrations of PFTBA in the atmosphere are low – 0.18 parts per trillion in the Toronto area – compared to 400 parts per million for carbon dioxide. So PFTBA does not in any way displace the burning of fossil fuels such as oil and coal as the main drivers of climate change.
From a climate change perspective, individually, PFTBA's atmospheric concentration does not significantly alert the phenomenon of climate change, still the biggest culprit is CO2 from fossil fuel emissions. Further, it has the highest radiative efficiency of any molecule detected in the atmosphere to date.
But PFTBA is long-lived. The Toronto researchers estimated that PFTBA remains in the atmosphere for about 500 years. Unlike carbon dioxide which is taken up by forests and oceans, there are no known natural "sinks" on Earth to absorb it.
The discovery of PFTBA and its warming potential raises questions about the climate impacts of other chemicals used in industrial processes.
Greenhouse Effect and Global Warming
Earth’s atmosphere works something like a giant glass greenhouse. As the sun’s rays enter our atmosphere, most continue on down to the planet’s surface. When they hit the soil or surface waters, those rays release much of their energy as heat. Some of this heat then radiates back into space.
However, several gases in Earth’s atmosphere — such as carbon dioxide, methane and water vapor —work like a blanket to retain much of this heat. That helps to warm our atmosphere. The gases do this by absorbing the heat and radiating it back to Earth’s surface. Such gases are nicknamed “greenhouse gases” because of their heat-trapping effect.
Due in part to the warming effects of the greenhouse gases, the global average temperature is about 15°C (59°F). Without the greenhouse gases the global average temperature would be much colder, about -18°C (0°F).
Why Global Warming?
Since the industrial revolution got into full swing in the 19th century we have been burning ever increasing amounts of fossil fuels (coal, oil, gasoline, natural gas) in electric generating plants, manufacturing plants, trains, automobiles, airplanes, etc.
Burning releases CO2 into the atmosphere (much the same as respiration does). These fossil fuels may have formed tens or hundreds of millions of years ago from the buried and preserved remains of plant and animal matter whose carbon originated via photosynthesis. Photosynthesis and respiration in plants, animals, fungi, bacteria, etc. leads to exchange of carbon between the CO2 in the atmosphere and carbon compounds in the organisms. But humans are now putting this natural carbon cycle out of balance.
Due to the emission of CO2, long-stored in fossil fuels, the percentage of CO2 in the atmosphere has increased very much. It has increased from about 289 parts per million before the industrial revolution to over 360 parts per million and still rising. Sometime during the 21st century the concentration of CO2 will be twice what it was before the industrial revolution.
With higher CO2 concentrations the greenhouse effect also becomes stronger and as a result global temperatures are expected to increase. This was originally proposed by a chemist named Arrhenius about a century ago.
Global average temperatures have risen by a small, but measurable amount in the past 100 years, apparently in large part because of the higher level of atmospheric CO2. Global average temperatures are expected to be on the order of 2-5°C (3.6-9°F) higher by the time CO2 doubles the pre-industrial concentration. The temperature rise will be small in the tropics but much greater at high latitudes.
Effects of Global Warming
A whole host of consequences will result. Some are probably already occurring.
Temperature measurements of the sea surface and deep oceans indicate that the oceans are warming. Rising ocean temperature causes rising sea level from thermal expansion of the water. Rising temperature also means melting glaciers and rising sea level through addition of melt water to the oceans.
Sea levels have risen by about 1 foot during the last century, mostly from thermal expansion of the oceans. Sea level is expected to rise closer to 3 feet during the coming century. Rising sea level will cause increasing coastal erosion, flooding, and property damage during coastal storms. Besides, it will also lead to loss of life from storms in low-lying coastal countries like Bangladesh and island nations in the Indian and Pacific Oceans.
Warmer sea surface temperatures will result in more and stronger tropical storms (hurricanes and typhoons). Coastlines already ravaged by these storms will expect to see more strong storms than before, increasing the loss of life and damage to infrastructure.
It is much more difficult to predict how regional and local weather patterns will change but there will certainly be changes. While higher temperatures will produce more rainfall across the globe, the regional rainfall patterns will likely change. Some areas will get more, some areas will get less.
The timing of wet and dry periods may change. But higher temperatures will also mean more evaporation. Higher temperatures may also mean stronger storms with damaging winds. All of these mean new risks and changing conditions for agriculture. Centuries old farming practices will have to change. Some areas may go from being marginal to becoming a breadbasket region, while other regions may go from major agricultural production to marginal.
Higher CO2 allows plants to grow faster (more CO2 enhances photosynthesis). That would sound good for agriculture. However, weed species tend to grow even better than crop plants under enhanced CO2 conditions so improved crop growth may be nullified by weed competition.
Natural ecosystems will be hard pressed to keep up with the changing climate because the rate of change will be faster than typical long-term natural climate change. Many species, especially plant species, will not be able to migrate to cooler areas fast enough to keep up with the warming of their habitats. And Arctic species will have no place to go and may not be able to adapt to the new conditions.
Severe summer heat in areas not used to it can lead to deaths. Higher heat and expansion of tropical areas may lead to increased incidence of malaria.
What can be done to slow Global Warming?
We can't realistically stop the rise of CO2 in the near term, but we can slow it and therefore reduce the consequences that will occur.
Reducing our energy needs: More fuel-efficient cars, less frivolous driving, more use of mass transit, improved insulation to decrease the fuel burned to heat and cool our homes, more efficient appliances, use of fluorescent rather than incandescent light bulbs, and careful monitoring of home electricity usage (turn off the lights and TV when not using them) can reduce our energy needs.
Conversion to alternatives like wind and solar power which don't burn fossil fuels and emit CO2 into the atmosphere
Planting large areas with trees will consume CO2 as the trees grow, until the forests mature.
Deforestation in the tropical forests around the world, especially in the Amazon and Indonesian rain forests should be stopped. This will keep that carbon in the forest rather than sending it back into the atmosphere as the trees are burned or decay and are not replaced by more.
Other techniques have also been proposed such as the chemical removal of CO2 from smokestacks and burial in deep underground reservoirs, though only certain areas can benefit from this.
Disposal in the deep ocean can be tried, where they will form a semi-stable compound under the cold temperatures and high pressures, though the CO2 could too easily come bubbling back up. These latter solutions are not well studied and wouldn't be especially cheap.
Moreover, leaders, societies, communities, local planners, farmers, health organizations, need to recognize the changing climate and rising sea level as they make plans for the future. Our citizens need to be educated as to likely changes and how best to deal with the changing conditions.