What is Global Warming ?

We hear alot of people throw around the term Global Warming in the news and yet I doubt that most people have any idea what the various commentators mean when they use the term.

When you hear some scientists talk about Global Warming they are talking about the increase in average temperature measurements over the last 100 years. Of course in that context one must ask several questions. Were all of the measurements done in the same locations, under the same conditions (i.e. in shade, in sun, etc.) and using the same type of instruments. How many measurement locations were used, 10, 100, 1,000 ? After all we are talking about trying to measure the average temperature across the globe. Would anyone seriously claim that GLOBAL temperatures are increasing (or decreasing) based on just measurements made in New York City over the last 100 years? Given that the average temperature in any location can vary 10-15 degrees in a single day its is easy to see that any measurements, past or future, are subject to many variables based on timing, location and equipment. Of course scientists make every effort to adjust their data to compensate for these variables. That means they change the data using educated guesses which makes thier "raw" not so raw or definative. Just what percentage of the raw data gets adjusted ? 10%, 50%, 90% ? So based on adjusted data from represenative (hopefully) locations over the last 100 years we are told that the average Global temerature has increased .6 degrees.

When you hear other scientists talk about global warming they are talking about the variables that cause global temperatures to rise or fall. Greenhouse gases are often cited as having a significant effect on trapping solar radiation in the earths atmosphere. Of course we hear about CO2 quite alot but less often mentioned are the other greenhouse gases, some of which are more significant factors in trapping solar radiation than CO2. The single most significant greenhouse gas is ...? Water vapor. Next in significance is Methane. It's strange that we don't hear much talk about those greenhouse gases. But wait, greenhouse gases are hardly the only variables involved in the trapping of solar radiation. There are clouds, the urban effect (making built up cities warmer than rural communities) and of course the actual amount of solar radiation the sun beams at us. Solar flare activity has a major impact on the amount of solar radiation that hits the planet and therefore can dramatically effect the amount of energy that can be trapped by these other variables. Is solar activity constant ? No, it is highly variable. So any reasonable discussion of greenhouse gases must include water vapor and methane and any discussion of trapping solar radiation should also cover clouds, the urban effect and solar flare activity. Seen any significant mention of these other variables in any of the global warming news programs, articles or movies ? Didn't think so.

But what about the significant increases in severe weather we have seen in the last several decades, isn't that a sign of Global Warming ? Some commentators have claimed that hurricanes have increased in severity and frequency in the last 10 years and claim that global warming is responsible. But they seem to be very selective in choosing what they are comparing recent storms to. The cyclical nature of GLOBAL huricane/typhoon activity is well established and the recent storm activity is well within what would be expected when reviewing that longer term cycle. Since they are talking about GLOBAL warming we should expect to hear them cite a global increase in storms. Why is it that we have only heard about an increase in hurricanes per year and not in the decrease in storms in other parts of the world and that GLOBAL storm acivity has shown no significant increase ? Are talking about global warming or Atlantic Ocean or Gulf of Mexico warming ? At least one senior hurricane scientist who had contributed to the last two Intergovernmental Panel on Climate Change (IPCC) Assessments and had primary responsibility for sections describing the past, present and future behavior of tropical cyclones has resigned over the distortions being pushed by others involved in the IPCC. His letter of resignation is enlightening 2500 minus one.

How about some of the other effects of Global Warming such as glacial an ice cap melting ? We are told that glaciers around the globe are shrinking and some commentators claim that all of the Greenland ice cap could dissappear within 100 years. How many glaciers are there ? 10, 20, 1000 ? How many of them are shrinking or another question, how many of them are increasing ? There are over 70,000, and scientists have studied a tiny fraction of them. While they have found some are shrinking them have also found that others are increasing in size. Again we don't hear about increasing glaciers today, but it wasn't too long ago that GLOBAL COOLING was the scientific consensus. (according to the article in NEWSWEEk magazine in 1971). Greenland ice has been the focus of many articles, news stories and movies. We are told that ice is being lost to the sea at an alarming rate and that sea levels could rise 20 feet if the entire Greenland ice cap melts. But is the Greenland ice cap actually melting ? Well, the folks at the University of Missouri-Columbia didn't think so Greenland Ice Sheet Changes Are Normal; No Evidence Of Long-Term Climate Changes, Researchers Say.

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