Yes, human activity causes global warming.

Global warming is casued by human activities specifically those increased greenhouse gases through deforestations and burning of fossil fuels. With the increase of global temperatures the sea level will rise, which will result in changing patterns of percipitation. These changes will bring severe weather occurences such as, heatwaves leading to drought, and heavy rainfall leading to flooding.

Naturally occuring greenhouse gases are composed of mainly water vapor, carbon dioxide (CO2), methan (CH4), and ozone. Since the begining of the industrial revolution scientist have study the naturally occuring greenhouse gases and the human activity which seem to increase and have a harmful effect on the globle.

The recent burning of fossil fuel alone have increased carbon dioxide levels by 75% in comparison to the levels in the past 20 years. The large shift in deforestation and land use has also contributed to this increase in emission of carbon dioxide.

During the 21st century, climate change is going to have a negative impact on millions of people due to coastal flooding, with a decreased agricultural food supply resulting in malnurtition and other health conditions. 

 

If this type of global warming continues through the 21st century the cost would out weight the benefits. Economic studies suggest a great loss in the worlds' Gross Demestic Product (GDP).

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