Today – 2/27 Critter in the News - Psittacosaurus Climate

Psittacosaurus – “parrot lizard” Ma in Asia Primitive bipedal relative of Triceratops – forelimbs only 58% as long as hindlimbs 8 species, most in any dinosaur genus Largest: 6.5 ft long, 45 lbs. Tail bristles! Same evolutionary origin as theropod feathers not established If the same, 1 st dino had feathers! Parental care – babies with ossified bones!

Large-scale atmospheric convection cells

Hadley cells Large scale transport of heat and moisture north and south away from the equator. Air rises at equator because of heat from sun. This air is moist due to evaporation Air transported N and S in upper atmosphere, cools, sinks at 30° Coupled cells equator-30°, 30°- 60°, 60°- poles

Surface circulation deflected by Earth’s rotation (Coriolis force)

More Weather Principles I Jet stream is a current of fast moving air in the upper atmosphere that steers storms Rising air = low pressure = precipitation Sinking air = high pressure = dry Storms form at equator and 60° Why does it ever rain in Tucson? – because Earth is much more complicated than this simple model

More Weather Principles II Winds around low pressure systems end up blowing counterclockwise around the center Winds around high pressure systems end up blowing clockwise around the center Trough is a map-view dip in the jet stream Ridge is a map-view rise in the jet stream Tucson winter rains associated with troughs Summer rains associated with heat, mountains

Jet Stream Seasonality

Water vapor loop

Atmospheric – Oceanic Circulation Relationship

El Niño Basic Idea Hadley cells + spinning Earth (Coriolis Force) create low level wind patterns Low level winds blow ocean surface driving ocean surface currents Tradewinds blow warm water into western Pacific When trades weaken, warm water rushes east, causing El Niño

The Current Situation Sea surface temperatures

El Nino SST Anomaly

Effects of El Niño – Old Idea

El Niño Regions

Peru

Peru

1 pt XC outline, groups of 3-4 Title 3 or 4 printed names 1) First paragraph – summary of content a) the experiment b) the interpretation … 2) Second paragraph – questions a) … 3) Third paragraph – affective discussion a)