so, i decided to check with an actual climate scientist on today's version of this merry-go-round, specifically pour's response. Here's what I got back:
1. Water vapor is not considered a "driver" of climate change by scientists because the amount of water vapor in the atmosphere changes with temperature, so it is referred to as a "feedback." Water vapor increases as the Earth's atmosphere warms, but so does the possibility of clouds and precipitation. That's why as temperatures warm some areas are expected to have a greater amount of precipitation - such as New England where we've seen an increase in precipitation and in the frequency of extreme rain events in the last few decades (these are not modeled increases, actual measured increases at weather stations). An example of another feedback: ice on the surface of the Earth reflects more light than land or the ocean, so more ice = less heat. As the globe warms and ice melts, more heat is absorbed by surfaces on the Earth which will lead to more heat. Gases, like CO2 and methane, are long-lived and when added to the atmosphere they block heat from escaping (this is a matter of simple physics - light enters our atmosphere and due to the radiation balance of the earth it has to escape - additional green house gases will bounce around certain wavelengths of light and as a result trap heat near the earth).
To address your argument about the "sun cooling" - NOAA does it best:
It's reasonable to assume that changes in the sun's energy output would cause the climate to change, since the sun is the fundamental source of energy that drives our climate system.
Indeed, studies show that solar variability has played a role in past climate changes. For example, a decrease in solar activity is thought to have triggered the Little Ice Age between approximately 1650 and 1850, when Greenland was largely cut off by ice from 1410 to the 1720s and glaciers advanced in the Alps.
But several lines of evidence show that current global warming cannot be explained by changes in energy from the sun:
Since 1750, the average amount of energy coming from the Sun either remained constant or increased slightly.
If the warming were caused by a more active sun, then scientists would expect to see warmer temperatures in all layers of the atmosphere. Instead, they have observed a cooling in the upper atmosphere, and a warming at the surface and in the lower parts of the atmosphere. That's because greenhouse gasses are trapping heat in the lower atmosphere.
Climate models that include solar irradiance changes can’t reproduce the observed temperature trend over the past century or more without including a rise in greenhouse gases.
2. " The earth was warmer during the "medieval warm period". The hockey stick BS was intended to wipe that out because the medieval warm period PROVES warming without CO2 changes. It was fraud. It does NOT correlate with any other measurement of earth temperature. If you believe it does, you believe in the flying spaghetti monster. And it's unbelievable that ANYONE can still back a group of people that are excusing out right fraud."
Yikes, sir. You are certainly passionate about this subject. And as a person who studies environments back during the Medieval Warm Period (which many scientists use as an analog for what we can expect with continued additions of green house gases into the atmosphere), I'm excited that you brought that up. The earth was even warmer than the Medieval warm period much further in the past. But what historical records (the gas bubbles trapped in ice cores and records from the sediment taken from the ocean floor) show us is that throughout the Earth's history, as temperature changes so does CO2 - they are linked (for the physical reasons I described above).
3. "This entire CO2 theory is being gutted step by step. EVERY piece of physical evidence refutes the theory. EVERY one. It all backs changes in solar activity. Yet...you guys all believe the theory. It's amazing. Most scientists just assumed climate scientists were doing good science and went along with it, but eyes are being opened."
I'm sorry, but the only thing that scientists are still debating is by just how much the weather and feedback mechanisms will change as a result of this manipulation of our atmosphere. Independent collections of physical evidence from scientists from a variety of disciplines support that human contributions to green house gases are altering physical process in the atmosphere. Do you disagree that CFC's (Chlorofluorocarbons) - which make up even less of a % of our atmosphere than CO2 - did not have an effect on the ozone layer? Because these compounds are now regulated in production and release because of the international agreements that acknowledged their contribution to the depletion of the ozone layer.
Humans have modified the atmosphere of the Earth and it is leading to broad environmental effects we still do not completely understand. What we do know, is that all models projecting changes as a result of this modification are suggesting we need to do something NOW to stop additional green house gases from entering the atmosphere. Can I ask you - what would be the harm in reducing green house gas emissions? If 97% of scientists are wrong - what's the worst we've done, reduced pollution?
Not sure if temperatures have increased where you live? Check out the University of Maine's Climate Reanalyzer -
http://www.cci-reanalyzer.org/
Enter your location and pick from different climate models or historical data developed or collected from all different scientists or agencies and map how much temperatures in the last decade are different from the 1950's for example. Here is a quick plot I made of just how different the average temperature from 1990 - 2012 is different from an average from 1950 - 1980. As you can see there are some places that are cooler in recent decades, but on a whole - the United States is warmer in the last decade. This is just a small comparison of what's been happening for centuries.
