Seismic risk The concepts of earthquake preparedness can help plan for emergencies arising from an earthquake. Building codes are intended to help to manage seismic risk and are updated as more is learned about the effects of seismic ground motion on buildings. This type of active improvement of mitigation of damage from earthquakes is known as seismic retrofit. However, the changes generally do not immediately improve seismic risk in a community since existing buildings are rarely required to be upgraded to meet the revisions. Seismic risk Seismic risk refers to the risk of damage from earthquake to a building, system, or other
Greenhouse effect Greenhouse effect The greenhouse effect is the process by which radiation from a planet's atmosphere warms the planet's surface to a temperature above what it would be without its atmosphere. If a planet's atmosphere contains radiatively active gases (i.e., greenhouse gases) they will radiate energy in all directions. Part of this radiation is directed towards the surface, warming it. The intensity of the downward radiation – that is, the strength of the greenhouse effect – will depend on the atmosphere's temperature and on the amount of greenhouse gases that the atmosphere contains. Earth’s natural greenhouse effect is critical to supporting