Are Humans Responsible?
According to NASA and a huge list of scientists, yes.
NASA states "Most climate scientists agree the main cause of the current global warming trend is human expansion of the "greenhouse effect" — warming that results when the atmosphere traps heat radiating from Earth toward space." Click here to read more.
The reason that the earth is habitable and not a frozen wasteland like the moon is because it has an atmosphere. Gases in the atmosphere prevent light at certain wavelengths from escaping, causing warming.
One of the most prevalent of these “greenhouse gases” is CO2 which human activity (the burning of fossil fuels) has caused to increase by close to 50% during the last 150 years (from about 280ppm – parts per million – to over 400ppm).
Can we just think about that again? There is almost 1.5 times the amount of heat trapping gas in the atmosphere of the earth in the last 150 years!