Why is one area of the earth’s land surface a desert, another a grassland, and another a forest? Weather and climate

I. Climate Climate- long term weather patterns Weather- momentary conditions of the atmosphere; created by the unequal heating & cooling of the earth’s surface. Temperature & Precipitation- major factors that determine an areas climate. Weather and climate both influence the amount of solar radiation the earth receives Temperature and precipitation– rain shadow effect and hydrologic cycle Humidity- the amount of water vapor air holds, which is dependent upon temperature.

Sun vertical at equator Northern Hemisphere Names Vernal equinox March 21 Sun vertical at equator Northern Hemisphere Names Winter solstice Dec. 22 Sun vertical at 23.5oS Winter solstice Dec. 22 Sun vertical at 23.5oS Summer solstice June 21 Sun vertical at 23.5oN Longest day June 21, shortest day Feb 21 Autumnal equinox Sep. 23 Sun vertical at equator

Earth further from sun Earth closer to sun The angle of incidence at a lower angle (winter)– light reaching the poles has been filtered– less solar heating Earth closer to sun

The radiant energy emitted by the sun. Solar irradiance- The radiant energy emitted by the sun. It is highest at the equator and lowest at the poles. We are interested in conditions near the Earth’s surface What are some factors that effect exposure to irradiance? Factors effecting exposure to irradiance: clouds, ice, pollution in atmosphere, volcanic ash, nutrients in water, phytoplankton bloom

Non-rotating Earth Convection cell model Non rotating model- when the density of air is lower than normal, the atms pressure drops--- low pressure zone When the density of air is higher than normal, the pressure increases--- high pressure zone

Add rotation and add landmasses unequal heating and cooling of the Earth

Physical properties of the atmosphere: Density Warm, low density air rises Cool, high density air sinks Creates circular- moving loop of air (convection cell)

Physical properties of the atmosphere: Water vapor Cool air cannot hold much water vapor, so is typically dry Warm air can hold more water vapor, so is typically moist Water vapor decreases the density of air

Physical properties of the atmosphere: Pressure A column of cool, dense air causes high pressure at the surface, which will lead to sinking air A column of warm, less dense air causes low pressure at the surface, which will lead to rising air

High pressure, dry climate 90o High pressure, dry climate 60o Low pressure, wet climate High pressure, dry climate 30o ITCZ intertropical convergence zone= doldrums Low pressure, wet climate 0o 30o 60o 90o

Idealized winds generated by pressure gradient and Coriolis Force. Horse Latitudes Around 30°N we see a region of subsiding (sinking) air.  Sinking air is typically dry and free of substantial precipitation. Many of the major desert regions of the northern hemisphere are found near 30° latitude.  E.g., Sahara, Middle East, SW United States. Doldrums Located near the equator, the doldrums are where the trade winds meet and where the pressure gradient decreases creating very little winds.  That's why sailors find it difficult to cross the equator and why weather systems in the one hemisphere rarely cross into the other hemisphere.  The doldrums are also called the intertropical convergence zone (ITCZ). Idealized winds generated by pressure gradient and Coriolis Force.  Actual wind patterns owing to land mass distribution..

ITCZ

Seasonal changes in the position of the ITCZ January Seasonal changes in the position of the ITCZ

July

Summer monsoon- Wet Winter monsoon- Dry

A major type of ecological community, determined largely by climate. Biome A major type of ecological community, determined largely by climate. Tundra Desert Forest What is a Biome? A large geographical region with a defined climate A group of interacting ecosystems that are spread over a large geographic area. Biomes are characterized by vegetation (or aquatic animal life) and largely defined by temperature and precipitation (or salinity).   Major Abiotic Factors that Influence the Distribution of Vegetation in Biomes: Temperature Sunlight Water Soil Distribution of Biomes influenced by Global Climate Patterns which are Largely Determined by: Input of Solar Energy: Solar radiation is distributed unequally across the earth. The sun is the ultimate energy source for life. Therefore, the distribution of energy ultimately influences the distribution of life. Movement of Earth in Space: Influences the flow of air and water (as liquid and vapor). Water is the biological medium for life on earth. Therefore, the distribution of water ultimately influences the distribution of life. Grassland Tundra Chaparral Taiga Grassland Desert Mountain Zones Tropical rainforest Temperate Evergreen Forest Temperate Deciduous Forest Polar Ice

Marine Biome Consists of oceans, coral reefs, and estuaries The ocean is the largest of all ecosystems. The ocean contains a diverse array of plants and animals at various depth zones. Coral reefs consist mainly of coral. Estuaries are areas where fresh and salt water environments converge. Mangroves, oysters, crabs and marsh grasses are examples of species in this environment.

Marine Biome

Hydrologic Cycle

Water Cycle in Hawaii

Rain shadow effect Rainshadow The third way that physiography influence climate is through the creation of a Rainshadow.  Colder air holds less moisture than does warm air. As a mass of warm air rises into an area of colder air, it will eventually cool to a temperature at which condensation will occur and a cloud will form. If you have already read ALTITUDINAL ZONATION, you know exactly what this rate is and how it works. If the air mass continues to rise and cool, condensation increases until precipitation (rain, snow, hail, etc.) occurs. This process take place regularly in the Cascade Range (in OR and WA) and Sierra Nevada Range (in CA). By the time the air mass reaches the top of these ranges, it has lost much of it original moisture. It then starts down the back side of the mountain. This causes the air to warm up and expand. The clouds to disappear as the little moisture that is left is now spread out over a wider area. We say that downwind side is in the "rainshadow" of the mountain. The deserts of the southwest extend as far north as eastern WA because of this rainshadow effect. In Hawaii, the wet side of an island is referred to as its "windward" side, while the dry, rainshadow side is known as the "leeward" of "lee" side.

The Coriolis effect The Coriolis effect Is a result of Earth’s rotation Causes moving objects to follow curved paths: In Northern Hemisphere, curvature is to right In Southern Hemisphere, curvature is to left Changes with latitude: No Coriolis effect at Equator Maximum Coriolis effect at poles Coriolis Effect: Coriolis effect is an inertial force described by the 19th-century French engineer-mathematician Gustave-Gaspard Coriolis in 1835. Coriolis showed that, if the ordinary Newtonian laws of motion of bodies are to be used in a rotating frame of reference, an inertial force--acting to the right of the direction of body motion for counterclockwise rotation of the reference frame or to the left for clockwise rotation--must be included in the equations of motion. The effect of the Coriolis force is an apparent deflection of the path of an object that moves within a rotating coordinate system. The object does not actually deviate from its path, but it appears to do so because of the motion of the coordinate system.

The Coriolis effect on Earth As Earth rotates, different latitudes travel at different speeds The change in speed with latitude causes the Coriolis effect

North Pole Buffalo moves 783 mph Quito moves 1036 mph 15o N South Pole equator Quito Buffalo equator 79oW Quito South Pole

Current Gyres Gyres are large circular-moving loops of water subtropical gyres Five main gyres (one in each ocean basin): North Pacific South Pacific North Atlantic South Atlantic Indian Generally 4 currents in each gyre Centered about 30o north or south latitude

Geostrophic flow and western intensification Geostrophic flow causes a hill to form in subtropical gyres The center of the gyre is shifted to the west because of Earth’s rotation Western boundary currents are intensified Figure 7-7

Western intensification of subtropical gyres The western boundary currents of all subtropical gyres are: Fast Narrow Deep Western boundary currents are also warm Eastern boundary currents of subtropical gyres have opposite characteristics

Boundary Currents in the Northern Hemisphere Type of Current General Features Speed Special Features Western boundary Currents warm swift sharp boundary Gulf Stream, Kuroshio narrow w/coastal circulation, deep little coastal upwelling Eastern Boundary Currents cold slow diffuse boundaries California, Canary broad separating from coastal shallow currents, coastal upwelling common

Geostrophic flow- caused by Coriolis deflection and Ekman transport

Wind-driven surface currents

Pacific Ocean surface currents

What do Nike, rubber ducks, and hockey gloves have to do with oceanography?

Ateam of volunteers and experts from the National Oceanic and Atmospheric Administration (NOAA) Hazardous Materials Division has released drift cards off Barber’s Point as part of a two-year study of the movement of surface currents off the Hawaiian Islands. The purpose of the study is to learn where floating pollutants might go if released from the south shore of O‘ahu. Made out of light wood and covered with non-toxic paint, the 4x6-inch cards are designed to biodegrade within a few months. NOAA is asking the public to help by reporting the date and location of the cards when they float ashore. Instructions and contact information are printed on the cards. Watabayashi said the study will help determine where future research should be directed. “The results will be used by academia, private industry, government, conservation groups, and others for various purposes. City managers, for instance, might use the information to aid in wastewater management decisions. Biologists might use it to characterize larval transport patterns which help identify habitat areas,” Watabayashi said. The data also may be used to verify trajectory models and track derelict fishing gear. The study is a collaborative effort of the NOAA National Weather Service, NOAA Coral Reef Conservation Program, the Clean Island Council Spill Response Cooperative, Chevron, Tesoro, and the U.S. Coast Guard. 2004-2007 Barber’s Point

Prediction of Marine Debris Drifting Trajectories Japan Tsunami 2011 Prediction of Marine Debris Drifting Trajectories Hawaii http://www.hawaii247.com/2011/04/07/tsunami-2011-japan-debris-likely-to-hit-hawaii-twice/

Sea Surface Temperature

Origin and paths of tropical cyclones Tropical cyclones are intense low pressure storms created by: Warm water Moist air Coriolis effect Developing hurricanes gather heat and energy through contact with warm ocean waters. The addition of moisture by evaporation from the sea surface powers them like giant heat engines.

A hurricane is a heat engine that derives its energy from ocean water A hurricane is a heat engine that derives its energy from ocean water. These storms develop from tropical depressions which form off the coast of Africa in the warm Atlantic waters. When water vapor evaporates it absorbs energy in the form of heat. As the vapor rises it cools within the tropical depression, it condenses, releasing heat which sustains the system. Hurricanes form over tropical waters (between 8° and 20° latitude) in areas of high humidity, light winds, and warm sea surface temperatures (typically 26.5°C [80°F] or greater). These conditions usually prevail in the summer and early fall months of the tropical North Atlantic and North Pacific Oceans and for this reason, hurricane "season" in the northern hemisphere runs from June through November. Given favorable conditions, the tropical disturbance can become better organized, indicated by falling surface pressures in the area around the storm and the development of a cyclonic circulation (counter-clockwise in the Northern Hemisphere). Surface pressures fall as water vapor condenses and releases latent heat into areas within the tropical disturbance. (Latent heat is the heat energy released or absorbed during the phase change of a substance—in this case, water vapor.) In response to the atmospheric heating, the surrounding air becomes less dense and begins to rise. As the warm air rises, it expands and cools triggering more condensation, the release of more latent heat, and a further increase in buoyancy, thus allowing more air to rise. A chain reaction (or feedback mechanism) is now in progress, as the rising temperatures in the center of the storm cause surface pressures to lower even more. Lower surface pressures encourage a more rapid inflow of air at the surface, more thunderstorms, more heat, lower surface pressure, stronger winds, and so on. If the storm is far enough from the equator (generally at least 8° of latitude), the Coriolis force will induce the converging winds into a counterclockwise circulation about the storm's area of lowest surface pressure. Meanwhile, air pressures near the top of the storm, in response to the latent heat warming, begin to rise. In response to higher pressures aloft, air begins to flow outward (diverge) around the top of the center of the cyclone. Analogous to a chimney, this upper-level area of high pressure vents the tropical system, preventing the air converging at the surface from piling up around the center. If this were to occur, surface pressures would rise inside the storm and ultimately weaken, or even destroy it.

Hurricanes produce storm surge Is a rise in sea level created by hurricane coming ashore Can be up to 12 meters (40 feet) high Causes most destruction and fatalities associated with hurricanes

Dynamics of a Tropical Cyclone Air moves toward zone of low pressure and veers off course to right L Counter current circulation in Northern Hemisphere

Hurricanes in Hawaii Hurricane season- June 1 to November 30 Hurricanes approach from both east and south Hawaii rarely gets hit Hawaii is subtropical Hurricanes rarely hit Hawaii By Jack Williams, USATODAY.comThe danger of a hurricane hitting Hawaii any single year is very low, but both meteorology and history tell you not to ignore the possibility, especially if you're building or buying a home there.First the meteorology. Hawaii is in the tropics and while the oceans around the state aren't as warm as those of the Caribbean Sea or Gulf of Mexico, the state does not have a chilly water barrier, like California's, which has helped keep any hurricanes from hitting that state — as far as anyone knows. (Related: California's tropical cyclones). In addition, hurricanes and tropical storms approach Hawaii from both the east and the south, with storms that form in the eastern Pacific Ocean off the Mexican Coast being the most common. (Related: Understanding Eastern Pacific hurricanes) The normal, east-to-west winds across the tropical Pacific push storms toward Hawaii, with a storm making it all of the way from time to time and many continuing west past Hawaii. Storm that wouldn't die From time to time, a hurricane sails past Hawaii to cross the International Date Line, which makes it a typhoon. In 1994, Hurricane John did even better. It formed over the eastern Pacific and grew into a hurricane on Aug. 11, with winds reaching 170 mph at one time. John weakened before hitting Johnson Island, south of Hawaii, where the U.S. Army destroys chemical weapons, but still did $15 million damage. All of the people on the island were evacuated before the storm hit. John crossed the Date Line on Aug. 28, becoming Typhoon John. It then turned around and crossed back to the east side of the Date Line on Sept. 8, to become Hurricane John again. before dying on Sept. 31. John covered a total of about 4,000 miles during its month as a storm. Also, a few tropical storms and hurricane form south of Hawaii and head north toward the islands. In fact, Hawaii's most devastating storm, Iniki in 1992, came from the south to pass directly over the Island of Kauai on Sept. 10-11, 1992 killing six people and doing $2.3 billion damage. Which brings us to Hawaii's hurricane history. Meteorologists have no doubt that hurricanes have been hitting Hawaii since the islands first pushed up from the bottom of the Pacific as volcanoes. Hawaiians had stories of storms from before Europeans and Americans arrived, but none seemed to be as aboujt storms as fierce as those told of in the legends of the people who lived around the Caribbean Sea before the Arrival of Europeans in the New World's tropics in the 15th century. In fact, even Weather Bureau meteorologists didn't realize until 1950 that some of the strong storms that hit Hawaii from time to time were tropical cyclones. (Hurricanes are tropical cyclones over the Atlantic Basin or the Pacific east of the International Date Line.) Robert Simpson and his staff at the Weather Bureau (It's now the National Weather Service) office in Honolulu recognized that a storm spotted east of the islands on Aug. 12, 1950 was a tropical cyclone, not an extratropical storm. (Related: How tropical, extratropical storms differ) They called it Hurricane Able because at the time forecasters used the World War II vintage international phonetic alphabet — Able, Baker, Charlie and so on — to name storms. This storm was later given the Hawaiian name Hiki. Simpson went on to become a towering figure in hurricane research and forecasting. He organized and ran the USA's and the world's first large hurricane research program, which continues today as the National Oceanic and Atmospheric Administration's Hurricane Research Division and to head the National Hurricane Center. He's the "Simpson" in the Saffir-Simpson hurricane damage scale. (Related: The Saffir-Simpson scale) Before 1950, meteorologists hadn't seen the differences between Hawaii's tropical cyclones and the island's extratropical "Kona" storms, which hit during the winter. The late summer, fall hurricane season can overlap the Kona season. Today, a bright eighth grader who has stayed awake during Earth science class could probably tell you many times which storms seen in satellite photos are tropical and which are extratropical cyclones. Simpson, and his 1950s colleagues, of course didn't have satellite photos and, as far as that goes, hardly any data about storms over the ocean except readings radioed from unfortunate ships that happened to stumble into a high winds and towering waves. Figuring out that "Able" was a hurricane was like putting together a jigsaw puzzle with many missing pieces. Since 1950, two hurricanes, including Iniki, have hit Hawaii. Here, "hit" means the storm's center came ashore on one of the islands. Others have come close enough to bring 74 mph "hurricane force" winds and to cause serious damage and to kill a few people. Hawaii's mountains can increase a hurricane's damage. First, mountains enhance rain, whether the state's normal day-to-day rain or rain from a storm. Rainwater rushing down mountains causes floods and flash floods. (Related: Trade winds govern Hawaii's weather). Sometimes a storm squeezes winds through valleys, making it speed up. Finally, in the past, and surely in the future, huge waves kicked up by far-away storms crash against Hawaii's beaches to wash higher than normal waves or eat away sand. The hurricanes to hit Hawaii were: •Dot, August 1959. Meteorologists on Air Force hurricane hunter airplanes estimated Dot's winds as 150 mph or faster on Aug. 2, which makes it the strongest hurricane ever recorded in the Central Pacific. But the storm weakened by the time at hit Kauai the night of August 6 with sustained winds measured up to 81 mph. At the time, Kauai was mostly agricultural but damages were estimated at $6 million in 1959 dollars mostly to the sugar, macadamia nuts and pineapple crops. •Iniki, September 1992. Iniki formed southeast of Hawaii and was heading toward the north when its eye went inland near Waimea on Kauai on Sept. 11 with peak, sustained winds estimated at 130 mph and gusts up to 160 mph. The fastest measured winds were just below 100 mph at Lihue. Iniki's winds caused widespread damage and storm surge and high waves did extensive damage on both Kauai and the Island of Oahu. Other notable Hawaiian storms included: •Nina, November 1957. After forming near Palmyra Island south of Hawaii, Nina headed north with its center coming within 120 miles of Kauai, but this was close enough for winds up to 92 mph to hit Kilauea Point, Kauai, and for heavy rain to cause serious floods. The fastest wind ever recorded at Honolulu International Airport — 65 mph — occurred during Nina. High surf on Kauai's southern shore accounted for most of the estimated $100,000 (in 1957 dollars) damage. •Iwa, November 1982. Iwa, like Nina, formed south of Hawaii and moved north to brush Kauai. It didn't produce 74 mph or faster hurricane force winds at any weather station, but the wind at Lihue came very close, 73 mph. Even without hurricane-force winds, Iwa did an estimated $239 million damage, mostly to hotels, and other tourist facilities and the growing number of homes that were replacing farms. It also knocked out power across Oahu, the island where Honolulu is located. •Estelle, July 1986. This storm come from the east, but was heading directly toward Hawaii when it was most intense — it then jogged to the south to miss the Big Island. Still, Estelle sent very large waves into beaches on the Big Island and Maui. Even though the storm's highest winds didn't hit Hawaii, the high waves did more than $2 million in damage.

Hurricane Path in Hawaii

Hurricane Iniki 1992

Hurricane Daniel Aug 2000 Just missed us.                                                                      Tropical storm Daniel was the first hurricane to threaten the Hawaiian Islands during the 2000 hurricane season. Fortunately, its path changed and passed north of the island chain, just missing the island of Maui. Just missed us.

Hurricane Andrew Bordering the eye of a mature hurricane is the eye wall, a ring of tall thunderstorms that produce heavy rains and very strong winds. The most destructive section of the storm is in the eye wall on the side where the wind blows in the same direction as the storm's forward motion. For example, in a hurricane that is moving due west, the most intense winds would be found on the northern side of the storm, since the hurricane's winds are added to the storms forward motion. Surrounding the eye wall are curved bands of clouds that trail away in a spiral fashion, suitably called spiraling rain bands. The rain bands are capable of producing heavy bursts of rain and wind, perhaps one-half or two-thirds the strength of those associated with the eye wall

Eddy A circular movement of water formed along the edge of a permanent current In an average year, 10-15 rings are formed 150-300 km in diameter Speed 1 m/sec Warm core ring Rotates clockwise Found on the landward side of the current Cold core ring (cyclonic eddy) Rotates counterclockwise Forms on the ocean side of the current

Sargasso Sea

Ekman spiral Ekman spiral describes the speed and direction of flow of surface waters at various depths Factors: Wind Coriolis effect

Ekman transport Ekman transport is the overall water movement due to Ekman spiral Ideal transport is 90º from the wind Transport direction depends on the hemisphere

Ekman Transport Water flow in the Northern hemisphere- 90o to the right of the wind direction Depth is important

Upwelling and downwelling Vertical movement of water () Upwelling = movement of deep water to surface Hoists cold, nutrient-rich water to surface Produces high productivities and abundant marine life Downwelling = movement of surface water down Moves warm, nutrient-depleted surface water down Not associated with high productivities or abundant marine life

upwelling downwelling

Langmuir Circulation

Global Warming

The E-M Spectrum

Fate of Solar Radiation Reaching the Earth reflection clouds snow and ice the earth’s surface atmospheric dust

Fate of Solar Radiation Reaching the Earth absorption atmosphere oceans land plant photosynthesis

Fate of Solar Radiation Reaching the Earth

The Greenhouse Effect

Greenhouse Gases Carbon Dioxide Methane Nitrous Oxide Water Vapor Ozone

Temperature Change (oF)                                                                                                                                                           Atmospheric CO2 (ppm) Temperature Change (oF) As can been seen in this figure, throughout the millennia, there has been a clear correlation between carbon dioxide levels and average global surface temperatures.  Looking back even further than the past 150 years (see figure 2B) gives further evidence of the human role in the enhanced greenhouse effect. Scientists say the world is entering largely uncharted territory as atmospheric levels of greenhouse gases continue to rise. Today’s carbon dioxide levels are substantially higher than anything that has occurred for more than 400,000 years. To understand the role of humans in increased surface temperature, go to figure 2D. Thousands of Years Before Present

Atmospheric CO2 & Surface Temperature Trends Atmospheric CO2 (ppm) Temperature Temperature Change (oF) Carbon Dioxide Year

Predicted changes with increased greenhouse warming Sea level rise Increased plant primary productivity Shifts in the distribution of plants and animals Water contamination and outbreaks of water-borne diseases Increased storm severity Potential melting or enlargement of polar ice caps Changes to patterns of rainfall More severe droughts or increased precipitation changes to ocean circulation patterns

Ice Age 18,000 years ago

Sea Level Changes due to Ice Ages and Ice Cap Melting

Changes in Mean Sea Level Mean Sea Level Rise                                                                                                                                                           Changes in Mean Sea Level One of the projected impacts of climate change is an increase in sea level. This figure shows the results of satellite measurements of the change in average global sea level over time. The slope of the graph suggests that the change in sea level is accelerating, which is expected as a result of global warming. Year

Summer Arctic Sea Ice Decline Comparison between 1979 & 2005                                                                                                                                                           This figure compares the extent of the summer arctic sea ice in 1979 with the extent of the sea ice in summer 2005. Since 1979, more than 20% of the Polar Ice Cap has melted away in response to increased surface air and ocean temperatures.

Late Summer Arctic Sea Ice Extent                                                                                                                                                           Sea Ice Extent (million km2) This figure demonstrates the trend in arctic sea ice extent, as measured in September – the annual summer minimum for sea ice extent – for each reporting year.  Year

                                                                                                        

Permafrost melting

Permafrost melting

Permafrost melting Drunken forest

North Atlantic Tropical Storms 10-year running average                                                                                                                                                           Named Tropical Storms This figure shows the number of named tropical storms in the North Atlantic, per year, smoothed out over a 10-year running average to minimize the noise in year-to-year variation. Since 1996, tropical storm frequency has exceeded by 40% the old historic maximum of the mid-1950s, previously considered extreme. Recent peer-reviewed studies suggest a link between higher sea surface temperature and storm frequency. Extreme weather events are a projected impact of global climate change. Year

1 Meter Sea Level Rise Waikiki http://www.soest.hawaii.edu/HMRG/FloodingOahu/index.php http://www.soest.hawaii.edu/coasts/sealevel/waikiki.html

Sea Level Rise Destroys coastal habitat (e.g. salt marshes, mangroves) Destroys human property Increases pollution Decreases freshwater supply

Effect on Marine Life Phytoplankton bloom due to light and temperature cues Changes will impact food web Hypoxia may result

Effect on Fisheries Migrations are in response to temperature May impact fisheries

Effect on Corals Coral bleaching Leads to loss of habitat and food for reef- dependent species

Currents Oceanic conveyor belt may change ocean currents Currents carry plankton Bring food and oxygen Distribute eggs and larvae Remove wastes and pollutants

Salinity Animals have a narrow range of tolerance Glacial melting inputs lots of freshwater

Acidity CO2 makes water acidic Corals and other calcium carbonate species can’t make skeleton Impact on plankton development impacts food web

Temperature Higher temperature results in less O2 - Results in hypoxia Ice melting leaves no resting/hunting areas for polar bears Antarctic Krill impacts food web

Invasive Species Algae smothers coral Invasive species out-compete natives

Weather Events More severe weather patterns El Niño Hurricanes Mudslides Forest Fires Drought

El Niño-Southern Oscillation (ENSO) El Niño = warm surface current in equatorial eastern Pacific that occurs periodically around Christmastime Southern Oscillation = change in atmospheric pressure over Pacific Ocean accompanying El Niño ENSO describes a combined oceanic-atmospheric disturbance

Oceanic and atmospheric phenomenon in the Pacific Ocean El Niño Oceanic and atmospheric phenomenon in the Pacific Ocean Occurs during December 2 to 7 year cycle Sea Surface Temperature Atmospheric Winds Upwelling

Normal conditions in the Pacific Ocean

El Niño conditions (ENSO warm phase)

La Niña conditions (ENSO cool phase; opposite of El Niño)

Non El Niño El Niño 1997

Non El Niño upwelling El Niño thermocline

El Niño events over the last 55 years El Niño warmings (red) and La Niña coolings (blue) since 1950. Source: NOAA Climate Diagnostics Center

Effects of severe El Niños

Inquiry What is a convection cell? What are current atmospheric CO2 levels? Why don’t we see many hurricanes in Hawaii? What is the fate of the majority of solar radiation that strikes the Earth? What is a drunken forest? Describe the rain shadow effect. How are biomes defined?