well greenhouse effect is really harmful for the earth. In brief it traps the heat emitted by the sun.
one of the main disadvantages of greenhouse effect is:-
the heat emitted from the sun is trapped by our earth with the help of carbon dioxide and CFC(Chlorofluorocarbon). this may also contribute to the global warming.
some of the early signs of global warming are:-
1) massive melting of ice caps, glaciers etc.
2) climate change
3) rise in sea level


SignificanceWhen carbon-based emissions from sources such as motor vehicles or coal-fired electric generating plants create greenhouse gasses, these emissions can trap heat within the atmosphere. The resulting greenhouse effect can then increase the planet's average temperature. Over time, the trapped heat can change climates and disrupt or destroy ecosystems that are not accustomed to the higher temperatures.EffectsIncreased temperature can lead to stronger and more destructive weather events, such as storms, hurricanes and tornadoes. These can be particularly damaging in parts of the world not used to dealing with severe weather.WarningThe greenhouse effect also leads to the melting of the polar ice caps, important because they keep the Earth cool. When these caps melt, it increases the level of the oceans and the Earth loses its cooling mechanis
disadvatage of global warming are ---
         on  health            
           temperatures have a direct impact on human health. When exposed to high levels of heat, people can suffer from elevated body temperature, heat exhaustion, heat cramps and heat stroke.
          on resources
        the epa  states that changing weather patterns and higher temperatures affect the amount and quality of water resources available for human consumption. Droughts can dry up scarce water resources, a dangerous condition in desert-like regions, such as the Southwestern United States, that have limited water resources. etc 
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