Atmosphere

• Envelope of gases present on the outermost boundary of Earth.

SPM Classification

• Based on
  • Size
  • Property

Size

• Measured in micron
  • PM 2.5
  • PM 10
  • PM 50

Property

• Hygroscopic
  • tendency to attract H₂ O molecules
    • inorganic salts
• Hydrophobic
  • being neutral
  • no tendency
    • no attraction for H₂ O
    • no repulsion for H₂ O
  • Includes
    • Carbon
    • pollen
    • dust
    • fine soil
    • fine volcanic ash

which area has the highest salts in atmosphere?

• Low latitude ➡️ high capillary action
  • salts exporting countries

Air Quality Index of India: 8 pollutants are measured

• PM 2.5
• PM10
• O₃
• CO
• NO₂
• SO₂
• Pb
• NH₃ emissions.

Pressure

• exerted by gas is due to the striking force

Comparing pressure at varying atmospheric heights

• Cold area ➡️ ⬆️ pressure at ground surface
• Warm area ➡️ ⬆️ pressure at the upper layer

Solar Radiation

Wavelength Measure

• Microwave & Radiowave
  • not fired from sun towards earth
• Green house gases can absorb long wavelength band
• water vapour comes under ➡️Green house gases
  • can absorb minor portions of IR
  • most abundant GHG
  • stay period in atmosphere is very less
    • undergoes condensation

Laws

Why earth emits short wavelength while earth emits long wavelength

Every object on Earth has the capacity to emit energy out of it, regardless of the temp value

• Good absorbers are good emitters
  • absorption faster 〰️ higher the emission
  • case in the deserts