Term | Definition |
weather | the conditions of atmosphere at a given location for a short period of time |
climate | the characteristic weather that prevails from season to season and year to year |
air temperature | measures how much kinetic energy the air molecules have |
air pressure | caused by the weight of atmosphere pushing down |
wind | the horizontal movement of air caused by differences in pressure |
humidity | moisture content of the atmosphere |
what is weather caused by? | the unequal heating of earth's surface, resulting in the formation of convection currents in our atmosphere |
in what layer of our atmosphere does weather occur? | troposphere |
how does an air mass form? | in our atmosphere, when air remains nearly stationary over a large section of earth's surface and takes condition of temperature and humidity from that location |
what causes air masses to move? | planetary wind belts |
what is a front? | boundaries between air masses, precipitation is likely to occur at these boundaries |
high pressure system | pleasant, sunny, clear weather, not cloudy or rainy, could happen in any season. wind moves clockwise, out and down |
low pressure system | lousy, cloudy, stormy weather, and depending on the season, could happen in any season. wind moves counterclockwise, in and up |
in the United States, which way do high and low pressure systems move? | the general movement is from west to east because of the prevailing westerly wind belt |
what is the difference between weather and climate? | weather is the daily atmospheric conditions for a specific location at a specific moment in time, climate is the average atmospheric conditions for a location over the course fo many months or years |
what are the layers of the atmosphere (in ascending order)? | troposphere, stratosphere, mesosphere, ionosphere |
what relationship does altitude and pressure have? altitude and temperature? | indirect, indirect |
what is atmospheric pressure affected by? | water vapor |
water vapor is light compared to what? | dry air |
what is the relationship between pressure and humidity? | indirect |
dew point temperature | temperature at which the air is holding the maximum amount of water, the air is saturated |
relative humidity | ratio of the amount of water vapor in the air, to the maximum amount it can hold. it is usually expressed as a percentage |
sling psychrometer | instrument to measure dew point and relative humidity |
how are winds described? | the direction they come from |
how do winds generally blow? | from high pressure to low pressure |