Are we so sure global warming is a result of humans burning fossil fuels? The Sun is a fiery mass of colliding particles.  We still know very little about what it is.  Could it possibly be the output of the sun fluctuates, like our weather, from one extreme to another.  From hot durations to cold durations and back again. I think global warming is the result of higher amounts of solar energy being released from the Sun; that's why it's getting hotter here.  I believe the question is important to all people on planet Earth, par excellence; is humanity, namely our consumption of fossil fuels, the cause of our predicament?
We know a lot about the sun. It isn't the main cause of global warming, as we can monitor exactly how much energy it is producing. The sun's output can fluctuate though, and we have yet to measure how badly this affects the climate.

So what is the main cause of global warming?

The main cause of global warming is emissions of C02 (carbon dioxide) into the atmosphere. C02 is odorless, colourless and non-toxic, however, it is the main cause of global warming. C02 is a greenhouse gas and  can stay in our atmosphere for about 20 years.

C02 causes something called the greenhouse effect. The greenhouse effect is the idea that long wave energy which is meant to go back to space, doesn't go back to space, and is instead captured by greenhouse gases such as C02. This causes lots of heat that should go off into space to be trapped inside the earth's atmosphere causing your temperature to rise.

Are there any other greenhouse gases?

Other greenhouse gases do exist, carbon dioxide is just the main one that causes the global warming. Other greenhouse gases include water vapor, methane, nitrous oxide and ozone.

Does global warming happen only on Earth?

Global warming happens all over the  solar system, planets like venus have many greenhouses gases in their atmosphere too, infact, on venus greenhouse gases alone make the planet 465 degrees celsius hot, which is way over the boiling point of water - 100 degrees celsius.

Do I disagree?

Yes, as there is too little evidence to prove that the sun fluctuates enough energy to gradually increase our climate dramatically, and we have also proven the effects of greenhouse gases in a planets atmosphere.