Blood group: An inherited feature on the surface of the red blood cells. A series of related blood types constitutes a blood group system, such as the Rh or ABO system. The frequencies of the ABO and Rh blood types vary from population to population.lood group: An inherited feature on the surface of the red blood cells. A series of related blood types constitutes a blood group system, such as the Rh or ABO system. The frequencies of the ABO and Rh blood types vary from population to population.
October 22, 2009. Running time 1:26. Climate scientists explain why theyâre sure the primary cause of global climate change today is increasing human emission of greenhouse gases â mainly carbon dioxide. Skip to main content
I strongly believe that global warming is a phenomenon caused by human activities, which results in a raise in greenhouse gases in the atmosphere. The scientific panel studying climate change stated that the proof of a warming is clear and the human activity has been the major reason for the change. Global warming is the result of warming of earth and sea due to the increased concentration of greenhouse gases. The main cause of global warming is the human activities which emit greenhouse gas which is known as the greenhouse effect. When sunlight reaches the earth it is absorbed by the earth and warms it.