Presentation on theme: "Composition of the Atmosphere Today’s Objectives 1. Distinguish gases between fixed, variable, and particulate 2. Identify the Greenhouse gases 3. Describe."— Presentation transcript:
Composition of the Atmosphere
Today’s Objectives 1. Distinguish gases between fixed, variable, and particulate 2. Identify the Greenhouse gases 3. Describe each type of gas 4. Discuss the role of each gas in the atmosphere Students will be able to:
3 Major Compositional Components 1. The Fixed Gases 2. The Variable Gases 3. The Particulates (aerosols) Lets look at each of these now
Nitrogen (N 2 ) – Oxygen (O 2 ) – Argon (Ar) – Neon (Ne) Helium (He) Hydrogen (H) Xenon (Xe) Fixed Gases very trace amounts 78.08% (78%) 20.95% (21%) 0.93% (1%) the same ratio around the planet
Properties of Fixed Gases Nitrogen – Inert Gas Oxygen – “multi-talented” respiration 1.Organisms use in respiration combustion 2.Used in combustion Greenhouse gas 3.A major Greenhouse gas Argon – Inert gas *residual from the first atmosphere*
Water Vapor – 0-4% Clear, tasteless, odorless Major part of Hydrologic Cycle Used for energy exchange evaporation (absorption) condensation (release) Latent Heat Flux (can’t feel) Greenhouse Gas
Oceans have about 10x more Product of combustion Ohio 7 th largest producer in the? Greenhouse Gas 315 ppm in ppm in 42 yrs Goes down in summer time – leaves Enhanced Greenhouse Effect Carbon dioxide – 365 ppm World True What About Global Warming?
Methane – 1.7 ppm Greenhouse Gas Fastest growing component 0.5% per year increase Most potent Where is its origin? 1.Breakdown of plant material by bacteria in rice paddies 2.Termite activity 3.Biochemical reactions in stomachs of cows COW FARTS…eww!!
Nitrous Oxide – 0.04 ppm Commonly known as laughing gas Increasing 0.25% per year Greenhouse Gas Forms in soil through a chemical process involving bacteria and certain microbes. (mutualism) Ultraviolet (UV) light destroys it
Ozone – 0.04 ppm 2 types – surface & atmospheric BAD!!!!!! Surface – BAD!!!!!! (Photo-smog) GOOD Stratosphere – GOOD Higher concentration ppm Absorbs harmful UV light from Sun 97% is found here Destroyed by Chlorofluorocarbons (CFC’s) – dreaded hole in ozone layer
Particulates (aerosols) Dust, sand, & soil from erosion Salt particles from the ocean Smoke and ash from forest fires Ash and gas from volcanism Pollution from … who else MAN! The nuclei for H 2 O to condense on The nuclei for H 2 O to condense on
Condensation Nuclei Hygroscopic Hygroscopic - “water seeking” H 2 O vapor condenses readily on this type of surface <100% humidity. Ocean salt is a common particle Not all good - sulfuric & nitric acid
Condensation Nuclei HydrophobicHydrophobic – “water-repelling” H 2 O vapor does not condense on these surfaces even when > 100% humidity Oils, gasoline, waxes are examples