Originally Posted by rich76
MYTH: The science of global warming is too uncertain to act on.
FACT: There is no debate among scientists about the basic facts of global warming.
The most respected scientific bodies have stated unequivocally that global warming is occurring, and people are causing it by burning fossil fuels (like coal, oil and natural gas) and cutting down forests.
The only debate in the science community about global warming is about how much and how fast warming will continue as a result of heat-trapping emissions. Scientists have given a clear warning about global warming, and we have more than enough facts — about causes and fixes — to implement solutions right now.
This is wrong. Yes, global warming is occurring. No, not all "respected" scientists think its caused only by burning fossil fuels. Is it being enhanced by humans? Possibly. But the only cause is humans? No.
MYTH: Water vapor is the most important, abundant greenhouse gas. So if we’re going to control a greenhouse gas, why don’t we control it instead of carbon dioxide (CO2)?
FACT: Although water vapor traps more heat than CO2, because of the relationships among CO2, water vapor and climate, to fight global warming nations must focus on controlling CO2.
Atmospheric levels of CO2 are determined by how much coal, natural gas and oil we burn and how many trees we cut down, as well as by natural processes like plant growth. Atmospheric levels of water vapor, on the other hand, cannot be directly controlled by people; rather, they are determined by temperatures. The warmer the atmosphere, the more water vapor it can hold. As a result, water vapor is part of an amplifying effect. Greenhouse gases like CO2 warm the air, which in turn adds to the stock of water vapor, which in turn traps more heat and accelerates warming. Scientists know this because of satellite measurements documenting a rise in water vapor concentrations as the globe has warmed.
The best way to lower temperature and thus reduce water vapor levels is to reduce CO2 emissions.
There are scientific studies that show that the increasees of CO2 over the last 100 years come AFTER the temperature has risen. Thusly implying that CO2 rises as a RESULT of temperature increases and not vice/versa
MYTH: Global warming is just part of a natural cycle. The Arctic has warmed up in the past.
FACT: The global warming we are experiencing is not natural. People are causing it.
People are causing global warming by burning fossil fuels (like oil, coal and natural gas) and cutting down forests. Scientists have shown that these activities are pumping far more CO2 into the atmosphere than was ever released in hundreds of thousands of years. This buildup of CO2 is the biggest cause of global warming. Since 1895, scientists have known that CO2 and other greenhouse gases trap heat and warm the earth. As the warming has intensified over the past three decades, scientific scrutiny has increased along with it. Scientists have considered and ruled out other, natural explanations such as sunlight, volcanic eruptions and cosmic rays. (IPCC 2001)
Though natural amounts of CO2 have varied from 180 to 300 parts per million (ppm), today's CO2 levels are around 380 ppm. That's 25% more than the highest natural levels over the past 650,000 years. Increased CO2 levels have contributed to periods of higher average temperatures throughout that long record. (Boden, Carbon Dioxide Information Analysis Center)
As for previous Arctic warming, it is true that there were stretches of warm periods over the Arctic earlier in the 20th century. The limited records available for that time period indicate that the warmth did not affect as many areas or persist from year to year as much as the current warmth. But that episode, however warm it was, is not relevant to the issue at hand. Why? For one, a brief regional trend does not discount a longer global phenomenon.
We know that the planet has been warming over the past several decades and Arctic ice has been melting persistently. And unlike the earlier periods of Arctic warmth, there is no expectation that the current upward trend in Arctic temperatures will reverse; the rising concentrations of greenhouse gases will prevent that from happening.
Again...by saying that people are the single cause of GW is just not right. Because its happened before. Are we enhancing the warming? Maybe. Sole cause? No.
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