A disease is any condition which results in the disorder of a structure or function in a living organism that is not due to any external injury. The study of disease is called pathology, which includes the study of cause. Disease is often construed as a medical condition associated with specific symptoms and signs. It may be caused by external factors such as pathogens or by internal dysfunctions, particularly of the immune system, such as an immunodeficiency, or by a hypersensitivity, including allergies and autoimmunity.
Current global observational and modelling capabilities allow scientists to produce estimates of the carbon budget, but many uncertainties remain. An EU-funded initiative was therefore established to provide more and better data on carbon dioxide (CO2) and methane (CH4) through a global carbon observation and analysis system.