Ojuorun aye ni ipele awon efuufu to seayika Ayé ti ibújìn aye dimu. Ojúọ̀run lo n da abo bo awon ohun elemin ni ile-aye nipa fifamu ultraviolet solar radiation, eyi n je ki ooru yi o mu loworo o si n seresile igbonasi to le wu ni ojo ati asale. Afefe gbigbe ni bii (gege bi ikunsi) 78.08% nitrojini, 20.95% oksijini, 0.93% argoni, 0.038% karboni oloksijinimeji, ati iye tasere awon efuufu miran. Bakana afefe tun ni iye orisi omi oru, to fe to 1%.

Àwòrán Ojúọ̀run ayé

Ojuorun ni iposi to to quintillion marun (5x10^18) kg, idameta ninu merin won wa ni tosi bi 11 km ojude. Ojuorun n tinrin si bi o se n goke si lai si bode kan pato larin ojuorun ati ofurufu. Giga 120 km ni ibi ti awon ipa tojuorun ti n han lara ni asiko ipadawole tojuorun fun oko-ofurufu. Ala Kármán ni 100 km bakanna tun je gbigba gege bi ala larin ojuorun ati ofurufu.

Afefe je kikopapo nitrijini, oksijini ati argoni ti lapapo won je "awon efuufu pataki" ojuorun. Àwon efuufu yioku ni a mo si "efuufu tasere" (trace gases), lara won ni awon efuufu ogba-alakaba bi omi oru, karboni oloksijinimeji, methani, nitrous oxide ati ossonu. Afefe jijo ni iye tasere opolopo awon adapo alegbogi miran. Opolopo awon ohun ounkoko aladaba le w ninu afijuwe afefe ti ko mo, bi dust, pollen ati spores, sea spray, volcanic ash ati meteoroid. Orisirisi awon amúdọ̀tí ile-ise elero na tun le wa, bi klorini bi apilese tabi adapo, fluorini (ninu adapo), merikuri ti apilese, ati sulferi ninu adapo bi sulferi oloksijinimeji (SO2).

Ikopapo afefe gbigbe, gege bi ikunsi[1]
ppmv: parts per million by volume (note: volume fraction is equal to mole fraction for ideal gas only, see Gas volume#Partial volume)
Gas Volume
Nitrogen (N2) 780,840 ppmv (78.084%)
Oxygen (O2) 209,460 ppmv (20.946%)
Argon (Ar) 9,340 ppmv (0.9340%)
Carbon dioxide (CO2) 387 ppmv (0.0387%)
Neon (Ne) 18.18 ppmv (0.001818%)
Helium (He) 5.24 ppmv (0.000524%)
Methane (CH4) 1.79 ppmv (0.000179%)
Krypton (Kr) 1.14 ppmv (0.000114%)
Hydrogen (H2) 0.55 ppmv (0.000055%)
Nitrous oxide (N2O) 0.3 ppmv (0.00003%)
Xenon (Xe) 0.09 ppmv (9x10−6%)
Ozone (O3) 0.0 to 0.07 ppmv (0% to 7x10−6%)
Nitrogen dioxide (NO2) 0.02 ppmv (2x10−6%)
Iodine (I) 0.01 ppmv (1x10−6%)
Carbon monoxide (CO) 0.1 ppmv
Ammonia (NH3) trace
Not included in above dry atmosphere:
Water vapor (H2O) ~0.40% over full atmosphere, typically 1%-4% at surface

Opoimule ojuorun

àtúnṣe

Awon ipele tosekoko

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Layers of the atmosphere (not to scale)

Ojuorun aye se pin si ipele pataki marun. Awon ipele yii pin si boya igbonasi npo tabi ndin pelu igasoke. Lati kukurujulo de gigajulo, awon ipele ohun ni yii:

Ojuoruntomoru (troposphere)
Ojuoruntomoru bere lati ojude titi de larin 7 km ni poles ati 17 km ni ibididogba, pelu iyato nitori ojuojo. Ojuoruntomoru gbona nitori igbelo okun lati ojude, bi bayi apa kukurujulo ojuoruntomoru lo loworojulo, be sini igbonasi nresile pelu igasoke. 80% iposi ojuorun wa ni ojuoruntomoru.




  1. Source for figures: Carbon dioxide, NASA Earth Fact Sheet, (updated 2007.01). Methane, IPCC TAR table 6.1 Archived 2007-06-15 at the Wayback Machine., (updated to 1998). The NASA total was 17 ppmv over 100%, and CO2 was increased here by 15 ppmv. To normalize, N2 should be reduced by about 25 ppmv and O2 by about 7 ppmv.