climate part1

Slide1: 

The Climate of Hawaii

Air Circulation & Ocean Currents: 

Air Circulation & Ocean Currents Air Currents Global Air Patterns The Coriolis Effect Hadley Cells Trade Winds Easterly Waves I once dated a guy named Coriolis...

Air Currents: Formation: 

Air Currents: Formation The sun’s warms the earth differentially, due to geographic variation The rate of heating is dependent on the rotational angle of earth as the sun hits it The earth is heated most around the equator This creates high and low pressure areas and leads to the rise and fall of air masses around the globe. As warm air around the equator rises, cool air from the poles is pulled in. Wind blows due to this cycle of air masses heating, cooling, and moving.

Global Air Patterns: 

Global Air Patterns Roughly 7 Patterns: Polar Easterlies Westerlies North East Trades Doldrums NE Monsoon South East Trades Roaring Forties

The Coriolis Effect: 

The Coriolis Effect As the Earth spins, a Coriolis effect is generated. This bends the currents to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. Wind’s tendency to blow from high pressure areas to low pressure areas contributes to this affect The currents generated are at a 45-degree angle to the prevailing winds. The wind tends to follow more east-west patterns rather than north-south

Coriolis Effects: 

Coriolis Effects In the North Pacific the four major, clockwise currents: the North Pacific current flowing west to east the California current flowing south, down the west coast of North America the North Equatorial current flowing east to west the Kuroshio current flowing north, up the east coast of Japan. The Kuroshio Current is a clockwise, circular flow called the North Pacific gyre. The Alaska current receives water from the North Pacific current moving in a counterclockwise gyre in the Gulf of Alaska. Results: move warm southern waters north causing: warm rains and thunderstorms move cold northern waters south, producing snowstorms and blizzards.

Hadley Cells: 

Hadley Cells Hadley’s Theory of 1735- Warm air rises at the equator & travels to the poles and cold air near the ground travels toward the equator They encompass an area between 5 and 30 degrees latitude and transport air northward aloft from the equator and then southward to the surface around 20- 30 degrees latitude Forms low pressure zone at Equator Forms subtropical highs Creates trade winds Air travels in diagonals due to Coriolis effect

Trade Winds: 

Trade Winds They are responsible for most of Hawaii’s weather, especially precipitation patterns Generated by Hadley Cells in the tropics, that blow out of the northeast Flow from Subtropical high to low pressure zone They are prevalent over 50% of the time They are steady and reliable during the summer months and weaker and less predictable during the winter

Seasonal Trade Winds: 

Seasonal Trade Winds January- center of concentration northeast of Hawaii July- center of concentration north of Hawaii

Trade Winds & Precipitation: 

Trade Winds & Precipitation The trade winds out of the northeast are forced upward by Hawaii’s mountains This air rapidly cools, resulting in precipitation, called orographic lifting A trade wind inversion occurs around 5000 ft as air descends The air above the inversion is dry, stable, and gently subsiding; the air below the inversion is cooler and moist. The Result: the windward side of the island, particularly around 3000 ft above sea level, is much wetter than the leeward side.

Easterly Waves: 

Easterly Waves Strong eastern ocean currents in the Pacific move long bands of warm water from Asia to Hawaii Coupled effects of the north easterly trade winds and the eastward ocean currents, the Hawaiian Islands produce the largest “wind wake” in the world The trades blowing from the northeast are split upon hitting the islands. The stronger winds move along the flanks of the islands, while the weaker winds move along the leeward sides. The trades and the winds from the ocean currents converge, and a wake is created.

Similarities in Air Currents & Water Currents: 

Similarities in Air Currents & Water Currents Water currents are generated and directly affected by air currents causing the following similarities: Warm air and water rise while cool air and water sink. In the oceans, density is controlled by temperature and salinity. In fall and winter, cooler temperatures cause the water to become dense and sink. This creates a convection cycle, which in turn creates an upwelling current. This upwelling brings nutrient rich waters to the surface. Both are affected and diverted by obstructions and landforms. Contrasting: Water currents move much slower than air currents, water travels at 1/100th of the driving wind speed.

When Weather Goes Bad...: 

When Weather Goes Bad... Subtropical Anticyclones Droughts Hurricanes Tsunamis Thunderstorms

Tsunamis, Hurricanes, & Thunderstorms, Oh my!: 

Tsunamis, Hurricanes, & Thunderstorms, Oh my! Biggest Problems: Physical Damage Threaten Tourist Economy Sometimes Fatal TSUNAMI - long-period sea wave produced by a submarine earthquake or volcanic eruption. It may travel across the ocean for thousands of miles unnoticed from its point of origin and build up to great heights over shallow water at the shore. Record of the tsunami of March, 9,1957, from the Hilo tide gage.

Slide19: 

I am El Nino. All other tropical storms must bow down before El Nino. Yo soy El Nino. For those of you who don't habla espanol, El Nino is spanish for.... The Nino.

El Niño: 

El Niño The periodic development of warm ocean water in the Pacific along the coast of South America, usually during the winter months ENSO- El Niño Southern Oscillation is the cycling of a Pacific Ocean pattern During El Niño- the trade winds die down in the central and western Pacific leading to a depression of the thermocline in the eastern Pacific, and an elevation of the thermocline in the west. Waters warmed from the western Pacific drift eastward toward the Americas La Nina is just the opposite and correlates with stronger than usual trade winds. Creates colder surface temperatures in the eastern Pacific.

Slide21: 

Interesting Facts: El Niño was originally recognized by fisherman off the coast of South America Noticed unusually warm water in the Pacific ocean, occurring near the beginning of the year. El Niño means The Little Boy or Christ child in Spanish. This name was used for the tendency of the phenomenon to arrive around Christmas. El Niño is often called "a warm event". La Niña means The Little Girl. La Niña is sometimes called El Viejo, anti-El Niño, or simply "a cold event" or "a cold episode".

ENSO & Hawaii: 

ENSO & Hawaii During an El Nino event, the air and ocean surface temperatures rise, and Hawaii tends to experience drought like conditions Hawaii tends to experience a higher frequency of hurricanes during El Nino events During a La Nina, Hawaii’s weather is generally cold & wet

Bibliography: 

Bibliography http://secchi.hmsc.orst.edu/education/relatedinfo/ocean.pdf http://www.ou.nl/open/dja/Klimaat/System/atmospheric_circulation.htm http://ousd.k12.ca.us/~webpg211/Can't%20delete/EarthquakesVolcanoes%202000/Period7/Holly%20and%20Jen nifer/picture_page.htm http://www.pmel.noaa.gov/tao/elnino/el-nino-story.html