Global Climate Change: Is It Real?
By Patrick Prokop
I've been interested in the science of global warming, now better described at global climate change, since I was a graduate student at St Louis University attaining my meteorological degree. I also took interest while at undergraduate school at Murray State University studying historical geology. That was in the middle 1970s. I could see there was a threat to adverse climate change back then but didn't give it too much thought as I was more concerned about pursuing my broadcast meteorological career which I started on August 27, 1977. In the mid 1980s new debates over global cooling versus global warming arose which enticed me to study the issue a bit more. However, today it has become the major topic of concern. It also has become quite obvious to me from reading the letters to the editor in the newspaper, browsing daily postings on Facebook, and listening to general everyday conversations that many people do not understand what global climate change is nor the cause behind it and the affects it will produce. Being who I am, a broadcast meteorologist (retired), I feel it is my duty and responsibility to learn more about this subject and to share that information to the public, to those who wish to learn more about it and review the information through the mind of someone who is involved with it in their every day work.
Science versus Politics:
Unfortunately, the science has become very political (and rather dangerous to discuss without sometimes a possible heated argument arising or a negative change of an opinion on one to the other). There have even been studies on those who believe or disbelieve in the issue of global warming and the causes behind it. One study that I came across in the many books that I recently read indicates that chances are, if you are a strong Republican, you don't believe global warming is caused by anthropogenic (man made) activities but instead, if you believe in global warming at all, believe it is caused by natural forces and cycles and nothing that mankind does will have any effect on climate. On the other hand, if you are a strong Democrat, you most likely will side with the science and believe that the warming is being either caused or greatly influenced by anthropogenic activities, i.e., from the massive burning of coal, oil and natural gas used to create electricity, heat our homes and provide our transportation. In either case, I try to avoid the political aspect of the issue and look at the science and that is what I present to you.
A better term for "Global Warming" is "Global Climate Change". The big question is; is it real? The answer is an absolute "yes". The next question then is: what is causing it? That is where politics begins. There are three schools of thought on the subject with one saying that it is a natural event, another that it is the results of human activity particularly in the burning of fossil fuels (coal, oil and natural gas) and the third, just a hoax. I can state right here and now, it is not a hoax … the earth is slowly getting warmer. If you look at historical natural events, overall, the climate should be either stable or slightly cooling. So the correct answer would be that this warming is caused by anthropogenic (human) activity. If that be the case, just what is it that we are doing that is causing global climate change?
What is Known:
If you have doubts about global warming, look at the numbers. The average global temperature has been rising over the past 100 years, not a whole lot, about one degree Fahrenheit globally, but is slowly accelerating, particularly since 1980. The decade of 2000-2009 was the warmest since modern global measurement began in 1880 with a value of 58.1°F compared to 56.7°F for 1900-1909. 2014 and 2015 have been the two hottest years since 1880 with 2016 even hotter yet (as through September)! This increase is much more pronounced in the Polar Regions with the value up by more than 4°F. The oceans are becoming warmer and more acidic (carbonic acid due to the absorption of CO2). The polar sea ice continues to shrink during the summer months whereas the Northwest Passage in the Arctic Ocean is becoming ice free. 2016 has seen the lowest Arctic sea ice extent since records began. Sea levels have risen about 10 inches since about 1880 and the glaciers worldwide are melting at an increasing rate while many animals and plants are becoming extinct at an alarming rate due to change in their habitat.
Charts and Graphs: ... Click on any chart for larger view ...
The Greenhouse Effect:
Whether we are responsible or not, one thing is evident, carbon dioxide levels of our atmosphere is increasing (See graph). This is the main greenhouse gas that influences the global average temperature. There are other strong greenhouse gasses as well; water vapor and methane are two others that have a large influence on the temperature. But unlike carbon dioxide, which can persist in the atmosphere for a hundred years, methane and water vapor are readily exchanged with methane lasting less than 10 years and water vapor continually being exchanged and precipitated out (rain/snow). However, as water vapor is a strong warming gas, and as the atmosphere warms, the amount of water vapor also increases, which can lead to additional warming. In addition, nitrous oxide and ozone also contribute to the greenhouse effect but to lesser amounts. An increase in the atmosphere's concentration of carbon dioxide (and other greenhouse gasses) is a climate forcing agent: it leads to a situation in which the planet absorbs more solar radiation than it emits to space as longwave radiation. This means the system (earth) gains energy.
The discovery of the natural greenhouse effect goes back to 1859 when the Irish scientist John Tyndal determined that carbon dioxide molecules intercept infrared radiation. In 1896 a Swedish scientist, Svante Arrhenius, found a relationship between atmospheric carbon dioxide concentrations and the average global temperature. This natural "greenhouse effect" he postulated, heats the Earth due to the presence of these gases. It is named this way because of a similar effect produced by the glass panes of a greenhouse. Shorter-wavelength solar radiation from the sun passes through Earth's atmosphere, and then is absorbed by the surface of the earth, causing it to warm. Part of the absorbed energy is then reradiated back to the atmosphere as long wave infrared radiation. Little of this long wave radiation escapes back into space. The radiation that is absorbed by these greenhouse gases are then reradiated back to the surface. These gasses account for the global average temperature of around 57.4 degrees Fahrenheit (see graph). Calculations indicate that without them, our planet would be a giant snowball orbiting the sun with a surface temperature of near zero Fahrenheit!
Composition of Atmosphere:
By volume, the atmosphere consists of 78.08% nitrogen, 20.9% oxygen and 0.9% argon with water vapor consisting of anywhere between 0-4% (displacing the others). Carbon dioxide consists of only 0.036% and methane at 0.00017% of our atmosphere by volume. Therein lies part of the problem: if so little greenhouse gases contribute to so much warming, what will happen if those levels are increased? To give you an idea as to what an increase in these gasses can do, all you need to do is look at the planet Venus. Venus and earth are like sisters in our planetary family, both similar in size and density. If you take earth and place it in the orbit occupied by Venus, the increase in solar energy would raise our global temperature from 57°F to around 149°F. You would expect Venus to be somewhere near that value but instead, this planet's temperature is around 867°F … a planet with a thick atmosphere of mostly carbon dioxide and water vapor.
Past Carbon Dioxide Levels:
Ice cores samples can reveal the Earth's natural climate rhythm over the last 800,000 years. When carbon dioxide levels changed there was always an accompanying climate and sea level change. Past measurement can be observed from Arctic and Antarctic ice. These cores show that carbon dioxide was always between 180 parts per million (ppm) and 300 ppm during the past 800,000 years. However, now it is 389 ppm (when I first wrote this article in 2009 ... in Oct 2018, it was up to 409 ppm, an increase of 20 ppm in 9 years!) and steadily increasing at a rate of nearly 2 ppm a year. Present CO2 concentrations are higher now than any time in the last 800,000 years. The bulk of this carbon increase is from the burning of coal, oil and natural gas, mainly used in the generation of electricity.
The Tipping Point:
An IPCC (Intergovernmental Panel on Climate Change ) report indicates that if nothing is done and we continue "business as usual", the concentration of CO2 will reach 537 parts per million by the year 2100. If we were to stop all carbon emissions today (which is purely hypothetical) and the CO2 level remained at 389 ppm, the global average temperature will still rise another 0.6 Degree Celsius or 1.1 degree Fahrenheit. However, with an increase to 537 ppm, the temperature would rise by more than 3° C (5.4° F). The critical level is 2° Celsius. With temperatures higher than the critical level would cause what is known as the "tipping point". This is where massive ice melts would cause the lubrication and then the undermining of ice sheets in the polar regions resulting in a cascade of ice to break and slide into the oceans, dramatically rising the sea level, not by inches but by feet !
The "Warming" is Very Fast
If you look at the swing in temperature over the eons, one thing begins to become quite clear. The WARM-UP is rapid ... VERY RAPID in a geological time frame. The COOL DOWN is slow ... VERY SLOW. This rapid warm-up is produced from what is known as "Climate forcing feedback". As the CO2 rises, so does the water vapor content ... two of which are very strong greenhouse gasses. But to get an extremely sharp rise in temperature over a short geological period, there needs to be another "forcing element". That might be what is known as methane hydrate. This "frozen" methane is trapped in the frozen tundra and in the ocean floors and there is a lot of it. If the tundra melts and / or the ocean bottom warms up, this methane would be released at a rapid rate into the atmosphere. Methane is more than 20 times more potent than carbon dioxide as a greenhouse gas and greatly increases the warming process. Once this event happens, there is no stopping it; hence the tipping point.
Effects of Global Warming:
If the world continues "business as usual", the carbon dioxide levels of the atmosphere will continue to increase (as well as methane and water vapor). It is a known fact that this causes global warming leading to global climate change. Also, as the ice continues to melt, the albedo … the surface reflectivity of sun's radiation … would decrease allowing for more solar radiation to be absorbed as heat that would have otherwise been reflected back into space if the ice had remained. This in turn would accelerate the melting process. This has happened many times in the past history of the earth but the rate of change from low concentrations to high concentration has occurred over periods of thousands and tens of thousands of years, allowing for nature to "adapt" somewhat to the climate changes. What is happening today is that same rate of change is occurring in just a few hundreds of years. The effects will cause rapid changes in climate patterns as well. The big warning signs are the decrease in polar ice and the warming of the oceans along with a slow increase in global temperature and the change in weather patterns leading to more drought and floods.
Cold Winters and Pleasant Summer Days Even With Global Warming:
With global warming, believe it or not, we will still have winters with very cold days and periods of very pleasant weather in the summer. However, there will also be more large swings in extreme weather patterns, particularly with droughts over traditionally rich farm lands and floods in others. Severe thunderstorms and tornadoes will also increase. Due to a more persistent El Niño type weather pattern, there could be fewer hurricanes (due to stronger winds aloft in the tropics), but the hurricanes that do form will have a potential to be stronger due to warmer waters in which they draw their energy.
Believe or Disbelieve:
Over the years, there has been a large increase in skepticism on the validity of global climate change, a change that is being caused largely from the massive burning of coal, oil and natural gas. A large part of this disbelief has been a result of huge campaigns by special interests groups, to confuse, cover up and discourage the public about the issues of climate change (and have done a very good job at doing so). Even though the signs in nature appear somewhat subtle, you must look at the average values over periods of years. If you are concerned about this subject, I strongly urge you to read many of the excellent books being published by the scientists who study this science and accept with skepticism information from those groups that are trying to deny it. Don't rely on information that comes only from blogs and unscientific articles. Be sure that what you believe is from proven and reliable sources. Try to understand that this situation is real. Will changes be sudden and without warning? Not likely and as mentioned above, the changes will be rather subtle but we will begin see changes and trends that will take many years to become entrenched that will lead to greater changes, probably beyond our lifetimes. But what about our children and grandchildren and future generations, what will they say about us? Will it be; "they saw the warning signs and did nothing!" or will it be; "Thankfully, they saw the problems and from their actions avoided calamity for us."
Some of the books that I've read with my brief comments. Click on the book to get more information from their web site.
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Last revised: ... Body: Friday, September 30, 2016
Graphs: Friday, September 30, 2016
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