Chapter 1 Earth and It's Atmosphere Flashcards
how is radiation created?
the sun converts hydrogen to helium and gives off radiation
what is the atmosphere?
a delicate life giving blanket of air
- mixture of gas molecules and small liquid particles
- most mass is held close to earth’s surface
what is the composition of the atmosphere?
Permanent Gases: N2 (78%), O2 (21%), Ar (.9%)
Variable Gases: H2O (0-4%), CO2 (417ppm), CH4+N2O+O3 (very, very small)
water and GHGs are both variable gases, but what makes them different?
water varies in place and time due to the hydrologic cycle, GHGs are increasing in concentration over time
how does the hydrologic cycle work?
evaporation/transpiration (from plants): liquid→gas
condensation: gas→liquid
precipitation: from atmosphere→surface
runoff: H2O moves along the surface
infiltration: surface→underground
why is “humid” air lighter than “dry” air?
dry air (mostly N2+O2), N2 (28amu) + O2 (32amu) humid air (mostly H2O), H2 (2amu) + O (16 amu)
what is the difference between ozone from the ozone hole, and ozone we see on the ground?
good ozone is found in the stratosphere, bad ozone is found in the troposphere and is a GHG (smog).
*the “ozone hole” just has less stratospheric ozone in areas
what is the difference between aerosols and pollutants?
aerosols: tiny solid or liquid suspended particles. Can be natural (dust, sea salt) or manmade (hairspray)
pollutants: only human-made impurities that can cause health hazards (burning fuels)
why do we have an atmosphere?
gravity pulls atmospheric gases towards surface
what did Earth’s early atmosphere look like?
-all planets in solar system started with same atmosphere made of hydrogen and helium. those gases escaped from earth because they were too light for earth’s gravitational pull to hold onto them
how did we get today’s atmosphere?
outgassing of CO2 and H2O came from cooling center of Earth. This caused rain and it created lakes and oceans. lakes and oceans acted as sinks absorbing CO2 from atmosphere
where did oxygen on earth come from?
plants evolved producing oxygen to form our current atmosphere
what is density?
mass/volume, how closely packed the matter is
what is pressure?
force/area, the push of the matter on objects, weight of molecules
what is the standard sea level pressure?
1013 mb
what is lapse rate?
change in temperature with a change in height (positive value=cooling with height)
- isothermal environment = no change in temperature with height
- inversion layer = change in the sign of the lapse rate, warming with height
what are the layers of the atmosphere and how does temperature change with height in them?
troposphere (where we live), T↓ w/ height
——–tropopause——–
stratosphere, T↑ w/height because good O3 absorbs UV+warming
——–stratopause——–
Mesosphere, T↓ w/ height
——–mesopause = coldest——–
thermosphere, T↑ w/height
what is the Ionosphere?
region of atmosphere electrified by charged particles
- not a true layer
- causes the auroras
what is the difference between weather and climate?
Weather: short term air temp, air pressure, etc.
-specific time/event
Climate: long term patterns and average weather
-30+ years of data needed
*we study weather and climate to see how they impact economic efficiencies
what are the 8 main weather elements?
air temperature air pressure humidity clouds precipitation visibility wind radiation
What is the difference between cyclones and anticyclones?
Cyclones: low pressure, wind blows counter-clockwise and in
Anticyclones: high pressure, wind blows clockwise and out
why does low pressure mean bad weather?
wind flows into low pressure system. the air converges in the middle and has to rise. as it rises it cools leading to condensation into clouds and precipitation
wind flows out of high pressure systems. dry air from above sinks and causes nice weather
what is a front and what are the 4 types of fronts?
Front=boundary between air masses
cold: cold air replaces warm air
warm: warm air replaces cooler air
occluded: cold front catches up to warm front and cold air is replacing cool air
stationary from: a front is no longer moving
what is wind?
- it describes air in motion
- always blows from high pressure to low pressure
- always define wind based on where it comes from (east winds come from the east)
