{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Chapter4 - Chapter 4 Atmospheric and Oceanic Circulation...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 4 Atmospheric and Oceanic Circulation Atmospheric Circulation Large-scale air circulation transports heat Sensible heat and latent heat in water vapor Atmospheric circulation must transport heat from regions of surplus (Equator) to regions of deficit (poles) Atmospheric circulation important transfer of energy (heat) and mass Imbalance between energy surpluses at Equator and deficits at poles partly resolved Atmospheric circulation has enormous impact on Earth’s weather patterns and ocean currents Human-induced pollution also spread Air Pressure Air is composed of gases Motion, size, number cause pressure to be exerted on all surfaces in contact with air Pressure would crush us except that it also exists inside us and pushes back Air pressure measured by a barometer (mercury or aneroid) For every 900 ft. rise in elevation, pressure diminished by 1/30 th of itself Lowered pressure decreases amount of oxygen entering the blood through the lungs At high elevations, atmospheric pressure less, boiling point lower 10,000 ft. boiling point is 194 o F Water takes longer to boil 1013.2 mb = normal air pressure at sea level Up to 1040mb = “high” Down to 982mb = “low” Wind Horizontal motion of air across Earth’s surface (Vertical updrafts and downdrafts due to turbulence) Wind is caused by differences in air pressure (pressure gradient) Two main properties are speed and direction Speed measured with anemometer Direction measured with wind vane Speed expressed as kilometers per hour (kmph), miles per hour (mph), meters per second (mps) or knots 1 knot = 1.15mph (nautical mile per hour) Driving Forces Within the Atmosphere
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Gravity Pressure Gradient Force Coriolis Force Friction Force Gravity Earth’s gravitational force almost uniform Equal compression of atmosphere near the ground, worldwide Density of air decreases with altitude Pressure Gradient High and low pressure areas exist primarily due to unequal heating of Earth’s surface Pressure gradient = difference in atmospheric pressure between area of higher pressure and area of lower pressure Air moves from areas of higher pressure to areas of lower pressure Æ Similar to concept of water flowing downhill The steeper the gradient, the stronger the wind Air pressure shown on maps as isobars Lines connecting points of equal pressure (like contour lines on topographic map) Distance between isobars indicates degree of pressure difference Closer isobars denote steeper pressure gradients High pressure air usually sinks (descends) and diverges Low pressure air usually rises (ascends) and converges
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern