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
Why we're tackling climate change. We know climate change is happening, and we know that it is caused by our actions. The Earth's atmosphere is warming, faster than it probably ever has. In some cases weather patterns, climates and natural environments are changing quicker than wildlife or people can adapt. So many of the world's biggest challenges, from poverty to wildlife extinction, are made more difficult by climate change. And things will get worse if we do nothing.