Transcript Hurricane Formation El Nino

Hurricane Formation
El Nino
Warm-up: water cycle review. Label
the arrows with these terms:
Condensation
Transpiration
Precipitation
Evaporation
What are the 2 possibilities for precipitation that hits
the land?
1.Runoff
2. Infiltration (to groundwater)
http://viewpure.com/jB7t4KKV38U
https://www.brainpop.com/science/weather/h
urricanes/
• Label Hurricane Katrina (2005) with the below
terms and describe what happens at each one:
• Which direction did Hurricane Katrina spin?
Counter-clockwise
• Which direction do all storms in the N.H. spin?
• Counter-clockwise
Spiral rain bands –
heavy rain and
storms; gusty winds.
Eye – sinking air, very
calm. No wind.
Eyewall – STRONG upward
winds; strongest part of storm!
How do these play a role in the
formation of a hurricane?
1. Convection – Causes Warm air to rises then it cools
sinks, forming circular motion in the atmosphere.
2.
Air Pressure - Very low pressure system in the
center of a hurricane forms causing winds to rise upward
because the air is warm and less dense.
How do these play a role in the
formation of a hurricane?
3. Water Cycle – Warm water Evaporates then the water
cools in the upper atmosphere and condenses into clouds,
and then it rains (precipitates).
1. Hurricanes, Cyclones, and Typhoons are all names
we use to describe the same weather phenomenon.
2. All of these storms form around the equator.
3. Why do you think they form there?
They form there because the water in the tropic
regions just north or south of the equator are the
warmest. They are generally the warmest during
late summer (hurricane season)
4. The warmer, the water, the more violent the
storm.
• Hurricanes happen when the oceans have
been warmed during summer months. In the
North Atlantic, hurricane season is from June
1 to November 30, but most hurricanes
happen during the fall.
Wrap it up:
a. What does a hurricane need as “fuel” to
form?
• Warm water!!! (80˚ F/27 ˚C)
b. What is one of the best ways to “kill” a
hurricane? (how does it die)
• Go over land!!!
• Move into cooler water.
Storms headed towards the Americans
come together off the West Coast of
Storms begin to rotate.
Africa.
Water Vapor rises
and wind speeds increase.
Storms organize and form a center of
extreme low pressure.
http://www.pbslearningmedia.org/resource/e
ss05.sci.ess.watcyc.hurrlife/how-hurricanesform/
150 years of Atlantic Ocean
Hurricane Data
http://www.cbsnews.com/htdocs/natural_disasters/hurricanes/framesource_flash.html
Fill in the 6 steps to hurricane formation
1. Warm air rises over the ocean near the equator.
2. Condensation of clouds form.
3. Winds start circling; the eye of the storm is created. As the
storm travels, wind speed increases.
4. Circling winds hit up to 74 mph or more. (Wind speed
determines category)
5. As it reaches shore, storm surges flood the area.
6. The storm begins to fade out as it comes onto land.
El Niño
http://esminfo.prenhall.com/science/geoanimations/animations/26_NinoNina.html
Questions
1. What is an El Niño?
Usually strong trade winds WEAKEN causing warm
water and rain to spread across the Pacific Ocean.
2. How does this impact the world?
In the Summer:
Asia/Australia – Drought
South America - Poor Fishing due to warmer
waters.
3. Are surface water temperatures warm or
cold off the coast of South America during
an El Niño?
Warm
4. How does El Nino affect the United States?
In the Winter:
Strong storms in the Northern states
Warm and rainy weather in the Southern states.
5. Does El Nino affect Texas specifically?
Yes, Texas experiences warmer and more rainy
winters.
6. Are there more frequent hurricanes during El
Nino? Why?
No. Weaker hurricane season in the Atlantic
Ocean.