Weather ch. 1

• In the sciences, the investigation or understanding of natural phenomena is through observation, theoretical explanation, and experimentation.
• Metric prefixes are multipliers prefixed to the unit i.e. 10 km (ten kilometers and a kilo = 10^3) 10 km = 10 x 10^3 m = 10^4 m = 10000 m.
• The two major molecule types in the current earth’s atmosphere are N,2 and O,2 (diatomic nitrogen and diatomic oxygen). N2 is the most abundant at 78% by number concentration and O2 is second at 21%
• The main source for diatomic oxygen O,2 in the atmosphere is from photosynthesis.
• The main sinks for diatomic oxygen O 2 in the atmosphere is from oxidation, exhalation, and the decay of organic matter.
• The global average temperature at the earth’s surface is currently around 59 degrees
• The global average temperature at the earth’s surface without greenhouse gases would be much colder (average temperature 0 degrees).
• The two dominant greenhouse gases in the earth’s atmosphere are carbon dioxide CO 2 and water vapor H 2 O.
• Earth’s gravity pulling down on the mass in the atmosphere explains why the largest air densities (or the most air molecules) in the atmosphere exist next to the surface of the earth.
• Density and pressure decrease rapidly with height in the atmosphere.
• The earth's atmosphere is divided into four layers based on the vertical profile of temperature. They are called the troposphere, stratosphere, mesosphere, and thermosphere.
• The local maximums in temperature for the temperature profile of the atmosphere correspond to heat sources from the absorption of solar radiation.
• The troposphere and mesosphere have decreasing temperatures with height.
• Most weather is confined within the troposphere and the troposphere contains 80% of the earth’s atmospheric mass.
• Ozone (O,3) in the stratosphere absorbs harmful incoming ultraviolet radiation and consequently protects life on earth.
• Diatomic Oxygen (O,2 ), the gas primarily responsible for the temperature increase with height in the thermosphere, is an effective absorber of the high energy ultraviolet radiation.
• Carbon dioxide concentration fluctuates in the northern hemisphere over the year reaching its highest concentration during the winter season (the CO,2 sink is less since plants are dormant).
• A tropical storm system with winds in excess of 74mph (118 km/hr) is called a hurricane.
• Extratropical cyclones are mid latitude cyclones or mid latitude lows pressure systems.
• A surface low pressure system in the northern hemisphere has air spiraling inward and counterclockwise.
• A surface high pressure system in the northern hemisphere has air spiraling outward and clockwise.
• A surface low pressure system has cold, warm, and occluded fronts about due to air masses being brought together.
• A surface high pressure system is typically where air masses form and has no fronts around (takes on temperature and moisture characteristics based on its latitude location and the type of surface (land or water).
• A low pressure system is associated with unsettled weather, i.e. clouds, winds, and precipitation.
• A high pressure system is associated with fair weather, i.e. clear skies and light winds.
• The main source of CO,2 is is decay of vegetation, volcanic eruptions, exhalation, and fossil fuel burning. The main sinks are photosynthesis and dissolving into the ocean.
• The main source of H2O is evaporation, and the main sink is precipitation
• The main source of diatomic nitrogen is decaying plant and animal matter, and the main sink is oxidation from lightning, and biological processes involving soil bacteria.
• ionosphere: electrified region within the thermosphere and upper mesosphere where large concentrations of ions exist.