•Convection is theheat transfer whichtakes place due tothe actualmovements ofparticles of the fluids.•This type of heattransfer takes placeonly in liquids andgases.
5.As air rises through the surrounding regions of greater density, it begins to cool & contract, becoming more dense. 1.Solar energy reaches Earth’s surface through 4.Warmer, less dense radiation. air rises carrying the heat upward by convection. 2.Energy is absorbed by 3.The heat energy of the surface Earth’s surface causing it to is transferred by air in contact warm. with this surface by conduction.A diagram explaining all the 3 methodsof heat transfer involved in the aircirculation.
•Convection currents arethose rising flows causedby heating or falling flowscaused by cooling inliquids or gases.•In air a rising current maybe caused by local heatingfrom dark soil or heatedbuildings.
•Convection currentscaused by cooling aremuch less obvious, buttake place in the upperatmosphere whenheated air is carried upand instead of levellingout in a layer cools andfalls.
How can weexplain whywarm air rises ,by the methodof convection?Here’s How.. NEXT
RETURN FLOW WARM SEA BREEZE COOL RETURN FLOW LAND BREEZE COOL WARMLocal heating can cause a local wind as air flows in to replace the risingheated air. It can be seen at a lake or sea shore where a daily onshorebreeze occurs as the land heats faster than the ocean in the morningand a daily off shore breeze as the land cools faster than the ocean.
Convection currents become critical in making windswhen warm moist (high humidity) air rises and cools.Condensing water vapour in the cooling air gives off alot of heat which drives the core area with droplets ofwater higher while cool air flows outward and down.This produces huge thunderheads of clouds withmoisture forming larger and larger drops which makestatic electricity and lightning. Under the rightconditions rotation can occur from the effects earthsrotation and a tornado or hurricane can result.