Weather vs Climate

Duration of events is key

Which leaves a record?

• Heat transfer occurs by:

– Conduction – atomic or molecular transfer

– Convection – mass movement

– Radiation – wave-like energy emitted

Annual energy flow

Variations in air pressureWith increased altitude

Relative contribution of greenhouse gases to global warming

• Role of variable gases and how they change– Carbon dioxide

• Anthropogenic sources• Natural sources

– Water vapor• Air temp controls amounts in atmosphere

– Ozone– Shield to UV rays– Attacked by CFCs and freon

– Methane• Decay of organic material; coal mines; animals

– Halocarbons• Cl, F and Br compounds; anthropogenic

– Aerosols [microscopic liquids and solids]• Desert dust, wildfires, volcanic gases

• Significant temperature changes in last 130 years

• Oceanic conveyor belt

Polar jet

Concave south

Concave north

• Note differences

• Stages of development are distinct

• Generation of electrical charges is key

Thunderstorm facts

• About 16 million occur worldwide each year

• Florida has about 100 thunderstorm days per year; Uganda has about 240

• 1,800 occur at any given moment• All produce lightning; severe storms

produce hail which can travel up to 100 mph

• All regions experience some activity

Storms that produced hail having an avg diameter > ¾ in

Lightning deaths during period 1959-2001

Organizational stage

<20% ofsupercellsgeneratetornadoes

Mature stage, up to 1 mile wide at base; form on trailing edge of supercell

Monthly average of tornadoes in U.S., 1950-1999

• Super outbreak of Apr 1974

Tornado deaths, by state 1950 - 1994

Date Location Deaths/Injured Notes

March 18, 1925 MO, IL, IN 695/2027 F5 – Tri-State Tornado

May 6, 1840 LA, MS 317/109 Nachez Tornado

May 27, 1896 MO, IL 255/1,000 St Louis Tornado

April 5, 1936 MS 216/700 Tupelo Tornado

April 6, 1936 GA 203/1,600 Gainesville Tornado

April 9, 1947 TX, OK, KS 181/970 Woodward Tornado

May 22, 2011 MO 158/> 1,000 Joplin, MO – 22mi grnd

April 24, 1908 MS, LA 143/770 Amite/Pine/Purvis Torn

June 12, 1899 WI 117/200 New Richmond Tornado

June 8, 1953 MI 115/844 Flint Tornado

Top 10 killer tornadoes