Though the intensity of the sun does change and solar heating of the earth is on an upward trend, it does not account for recent global warming. David Appell’s article in Scientific American describes how the sun is very slowly expanding and increasing in the intensity of its brightness. Scientists predict that in 7.6 billion years, the sun will reach its full size and it will be 3,000 times brighter. (It is an interesting and revealing article, and here is the link if you would like to read more: http://www.scientificamerican.com/artic … rth-maybe/) Though the sun’s size and intensity is increasing, this growth is occurring over billions and billions of years. Thus the fast increase in temperatures on earth cannot be attributed to the sun’s growth.

According to the National Academy of Sciences of the US, In the past 30 years, the earth’s temperature has increased 0.2 degrees Celsius every decade. Though this may seem small, global temperature rising this much in just 30 years is huge in magnitude considering that in the past approximat ely 13 decades, the temperature has only risen 0.85 degrees Celsius. At the current rate of 0.2 degrees Celsius per decade, after 13 decades the global temperature would rise 2.6 degrees Celsius. This illustrates the increasing growth rate of global temperature and how there are factors besides the increasing heat of the sun that are driving global warming.

Furthermore, the slight increase in solar intensity could not have possibly caused these changes in temperature because tiny reflective particles that enter the atmosphere from volcanic eruptions prevent solar energy from affecting temperature on earth. In their report of “How Does the Sun Affect Our climate?” the Union of Concerned Scientists states that “incoming energy from the sun that encountered these particles was reflected back into space.” This evidence exemplifies how the magnitude of climate change is currently beyond the sun’s capabilities. We must hold ourselves accountable for recent global warming and not hide behind the façade that global warming is an evitable effect of growth in solar intensity.

This looks really good I think that you have backed you post with a lot of information that supports your theory.

I think one of the main reasons people aren't convinced climate change is real, or they blame the sun is because they don't really understand climate change and the factors that warm the Earth. People know the sun warms the Earth, but many don't understand how. When you say greenhouse gas or greenhouse effect, people think carbon dioxide and warming up the Earth. However, it's not just carbon dioxide, and the greenhouse effect is more than just warming the Earth. Water vapor, methane, nitrous oxide, and chlorofluorocarbons are all greenhouse gases and, except chlorofluorocarbons, they all occurred naturally and were present on Earth since the beginning of its formation. However, the amount of greenhouse gases has increased tremendously in the last century, especially after the Industrial Revolution. The burning of fossil fuels is one of the most prominent factors towards the increase in carbon dioxide in the atmosphere. Fossil fuels contribute to global warming because when they're burned, carbon that was trapped for millions of years gets released into Earth's atmospher e which can't maintain the environmental balance with the rate of burning fossil fuels. Another reason for the increase in greenhouse gasses is because methane has increased in the atmosphere mainly because of industrialized and grand-scale agriculture, the rapid increase in waste,  and rise in domestic livestock in the last century. There are many more factors that contribute to the increase of greenhouse gases which contributes to global warming, but the point is human activity is a huge factor to blame. The rapid advancement in societies and increase in population has created a lot of stress on Earth's resources. Already, there are significant signs of changes in Earth's environment that will eventually completely change the way species on Earth live.

I think that your post is really important. Our carbon affect seems intangible most of the time; we associate it more with possible effects than things that are actually occurring. Appell's research on the sun disproves this belief. Global warming is very real, and has become an undeniable fact, and understanding our own personal affect on the process is essential. It is scary to think of the future of global warming if the sun continues to grow at such a rapid rate. David Appell's article takes the consequences of this to a level beyond global warming as well; in 7.6 bullion years, the sun, extending 20% beyond the surface of the earth, will engulf the earth. Although Appell's hypothesis is not fact, it does implement a sense of urgency. Our carbon affect his more powerful than we imagined.

This was very well researched and thought out! To add to the main idea that humans may have caused climate change, the average increase in solar radiative forcing since 1750 is much smaller that the increase in radiative forcing due to heat trapping gases. Translated into plain english- gases released by us, the people, are having a significantly greater impact on the raising of the global temperature than radiation from the sun. To back this up, we could discuss the eruption of major volcanoes in the twentieth century. When volcanoes erupt, they spew tiny reflective particles into the atmosphere. When incoming energy from the sun encounters these particles, the energy is reflected back out into space. This means that we should have experienced a slight cooling in the late twentieth century. Instead, we have overpowered natural processes and caused an increase in temperature. I think this backs up your point that humans should cary the blame, not the sun, when it  comes to global warming. Global warming is not due to natural processes, but is instead due to human interactions with our environment.

here's my source if anyone would like to read more http://www.ucsusa.org/global_warming/sc … gtmvxNViko