Complex sentence: A significant, empirically demonstrated, positive relationship exists between the surface temperature and concentration of Greenhouse gases such as CO 2 in the atmosphere, which has a drastic negative impact on the global extent and stability of the cryosphere.
Split into simpler sentences: A significant, empirically demonstrated, positive relationship exists between the surface temperature and concentration of Greenhouse gases such as CO 2 in the atmosphere. The higher concentration, in turn, has a drastic negative impact on the global extent and stability of the cryosphere.