Cloud cover: affects energy received and retained. Proximity to water: modifying effect of water bodies on adjacent land. Elevation: systematic reduction of temperature and reduced greenhouse effect. Slope and aspect (terrain): radiation intensity and surface warming. Balance between incoming short wave radiation and outgoing long wave radiation. Latent heat transfer: exchange of heat during evaporation (cooling) or condensation (warming) Insolation and net radiation show similar daily patterns. During day, net radiation is positive and ground heats. At night, net radiation is negative, and earth cools by radiating longwave radiation to atmosphere. Greater in summer than winter as sun is higher in sky and daylight period. Positive over 24 hour period in summer. Daily cycles: temperature above occurs, moving warm air upwards away from surface. As net radiation becomes positive, surface temperature rises and transfers heat air. Air temperatures continue to rise well after solar insolation peak at noon. Temperature is coldest 30 minutes after sunrise.