N2O also acts as a greenhouse gas. This means that N2O (as well as other atmospheric gases) allows certain wavelengths of visible and UV radiation to reach the earth's surface where some of this radiation is converted into IR radiation (heat), which results in warming of the earth's surface. The N2O traps the IR radiation as it radiates from the earth's surface resulting in a warming of the atmosphere. Thus, N2O can contribute to an enhanced greenhouse effect, in which anthropogenic chemicals increase the amount of IR radiation that is reflected back towards the earth's surface, causing a gradual rise in temperature of the atmosphere. Over in time, such a rise in temperature could result climate changes, causing already arid climates to become drier and rainy climates to become even wetter. Drastic climate changes could result in the disturbance of growing seasons, increased occurrences of floods, and a rise in ocean levels due to the melting of polar ice caps.