Transcript Chapter 2

Chapter 2: The Atmosphere and The Ocean
Key Points: Summary of Chapter 2
1. The global wind system acts to redistribute heat between
lows and high latitudes.
2. Coriolis force influences the direction of winds as they
move from regions of high pressure to regions of low
pressure.
3. Differential heating between land and water greatly
influences global wind patterns.
4. Mid-latitude weather is systems are cyclones and
anticyclones. Low latitude circulation is characterized by
spiraling Hadley cells.
5. Heat is transported to higher latitudes through convective
motions and latent heat transfer.
6. Ocean-Atmosphere interactions are most intense (strong
coupling) in the tropics.
Ocean-Atmosphere Interactions
Intense coupling in the tropics
Moisture content and stability
SST – Hadley Cell Intensity – Location ITCZ
Warmer SST = More buoyancy = Inc. Convection
Cyclones – Hurricanes – Typhoons
low pressure centers, depressions from higher
latitude, vortices associated with ITCZ, easterly
waves (O 2500km)
Western basin – trade wind T inversion weakest
Cylone (anticylone) generation requires geostrophic conditions
Intense convection of warm humid air = cumulonimbus clouds & Thunder storms
Release of latent heat increases buoyancy of upper air = enhanced convection
Critical SST 27o – 29o C
Surface winds influence deeper ocean structure
Thickness of Mixed Layer
Decay: land, cooler water, upper level wind shear
http://svs.gsfc.nasa.gov/vis/a000000/a003200/a003261/
TRMM Microwave Imager (TMI) sea-surface temperatures
from August 22 - Sept. 23, 1998. Blues represent cooler water,
greens and yellows are warmer water.
Deadliest Hurricanes in the United States (U.S. Mainland)1
Rank Hurricane
Year
Category2
Deaths
3
1.
Galveston, Tex.
1900
4
8,000
2.
Lake Okeechobee, Fla.
1928
4
2,500
3.
Katrina (La./Miss.)
2005
3
1,800
4.
Florida Keys/S. Tex.
1919
4
600
5.
New England
1938
3
600
6.
Florida Keys
1935
5
408
7.
Audrey (SW La./N. Tex.)
1957
4
390
8.
NE U.S.
1944
3
390
9.
Grand Isle, La.
1909
4
350
10.
New Orleans, La.
1915
4
275
10.
Galveston, Tex.
1915
4
275
1. 1900–2007.
2. At landfall. Saffir-Simpson Hurricane scale: Cat. 1 = weak; Cat. 5 = devastating.
3. May actually have been as high as 10,000 to 12,000.
4. Approximated.
5. Over 500 of these lost on ships at sea; 600–900 estimated deaths.
6. Some 344 of these lost on ships at sea.
Source: National Oceanic and Atmospheric Administration (NOAA).
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