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What is climate ?. The pattern of weather that occurs in an area over a long period of time, such as 30 years. It determines the type of plants or animals that can survive in an area. It also influences us and how we live! *How might it influence us and how we live??. Climate.
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The pattern of weather that occurs in an area over a long period of time, such as 30 years. • It determines the type of plants or animals that can survive in an area. • It also influences us and how we live! • *How might it influence us and how we live?? Climate
What type of things do scientists look into to help them determine an area’s climate? • Temperature • Precipitation • Air Pressure • Humidity • Days of Sunshine Climate • Other factors that affect climate are latitude, landforms, location of lakes and oceans and ocean currents.
What is latitude? • A measure of distance north or south of the equator. • Regions close to the equator receive the most solar radiation. • The tropics is the region between 23.5 degrees N and 23.5 degrees S have temperatures that are always hot. Latitude and Climate
The polar zones extend from 66.5 degrees N and 66.5 degrees S. • Because the sun hits these zones at a low angle, spreading its energy over a larger area, these regions are never warm. Latitude and Climate
Between the tropics and the polar zones are the temperate zones. • Temperatures here are moderate. • What zone do you think the United States is in?? Latitude and Climate
Large bodies of water such as oceans • Ocean currents • Mountains Factors that affect climate within these zones…
Factors that affect climate within these zones… • Water heats up and cools down more slowly than land does. • When water absorbs and gives off heat, it affects climate. • Ocean currents affect coastal climates. • Warm currents begin near the equator and flow toward higher latitudes warming land as they pass. • Mountains have a colder climate than sea level climate.
Factors that affect climate within these zones… Rain Shadow- affects climate on opposite side of mountain. -As air rises along the upside (windward side) of a mountain, it cools, condenses and falls. -Along the downside of a mountain (leeward side), air sinks, heats up and dries the land.
Factors that affect climate within these zones… • Large cities affects local climates because parking lots, streets and buildings heat up causing the air to also heat up. • Pollution traps this heat and creates a “heat-island effect”. • Temperatures in a city can be warmer than in surrounding areas.
Classifying Climates • Climates are also classified • Climatologists divided earth’s climates into 6 different groups: • Tropical • Mild • Dry • Polar • High Elevation • Continental
Classifying Climates • The 6 different groups are then separated again into smaller groups. • For example: • Dry climates are separated into 2 types: • semiarid – 10-20 in. of annual rainfall • arid – less than 10 in. of annual rainfall
Adaptations • Can we find pine trees in the desert? • Can we find cacti in the rainforests? • All plants and animals fit their climatesbecause of certain adaptations. • Adaptations are any structure or behavior that helps an organism survive in its environment. • These adaptations are developed and inherited over time and are suited only for a particular climate.
Structural Adaptations • Structural • Some organisms have bodystructures that help them adapt to a climate. • Can you think of any??? • Polar bears have thick fur • Cactus has thick stems, waxy surface and needles • Monkeys have long arms to swing from tree to tree
Behavioral Adaptations • Behavioral • Some organisms display behavioral adaptations that help them survive in a particular climate. • Ex: Hibernation • During hibernation, an animal’s body temperature drops along with its metabolism allowing animals to survive without any food.
Estivation • Estivation is similar to hibernation but occurs during the summer months instead of winter. • Animals who hibernate escapes harsh winters, however animals who estivate will escape the hot and dry summer weather. • Animals such as snails, fish, and frogs will estivate by burrow and cover itself in the mud to help them stay cool.
Climatic Changes • Why do we have seasons?? http://www.youtube.com/watch?v=DuiQvPLWziQ
Climatic Changes • Earth’s Seasons • In temperate zones where we live, we experience 4 seasons: fall, winter, spring & summer. • Seasons are short periods of climatic change caused by changes in the amount of sunlight we receive. • What are seasons like in the tropics?? • The tropics do not have much of a temperature change each season, however they do experience rainy and dry seasons.
Climatic Changes • High Latitudes • Higher latitudes near the poles have great differences in temperature and number of daylight hours. • During our summers, the north pole has 6 months of sunlight while the south pole has 6 months of darkness
El Niño/La Niña 5TH GRADE SCIENCE
El Nino/La Nina • El Nino • When weaker trade winds allow warmer water to flow back eastward, towards the United States • Leads to heavy precipitation across the US • La Nina • When stronger trade winds push warm water westward, away from the United States • Leads to cooler, drier weather http://www.youtube.com/watch?v=7FVZrw7bk1w&feature=related
What is El Niño? • El Niño is a climate pattern where the water in the Pacific Ocean near the equator gets hotter than usual and affects the atmosphere and weather around the world. • El Niño climate conditions occur every few years, and they are not predictable. • El Niño is Spanish for The Little Boy. It refers to the Christ child and was named by Mexican fisherman, who noticed the climate pattern often formed around Christmastime.
El Niño • In a normal year, the warmest water is in the far western Pacific. This forms thunderstorms. • (Graphic Credit: USA TODAY) • In an El Niño year, the warmest water moves eastward across the Pacific. Thunderstorms disrupt the jet stream changing the weather pattern.
What type of a climate pattern do we see with an El Niño? • The climate pattern can change the weather of the United States, particularly in California and the southern states. • Usually, El Niño brings more rain and higher temperatures. • Also, warm ocean currents come farther north and all kinds of tropical fish can be caught in the waters far north along the United States West Coast. • El Niño may also bring warmer than normal winter temperatures to the eastern part of the United States.
What is La Niña? • La Niña is sort of the opposite of El Niño. • During a La Niña, the water in the same area along the equator gets colder than usual. • This, too, affects weather around the globe and in the U.S. • According to scientists, La Niña cycles generally create a more active hurricane season in the Atlantic.
What type of climate pattern do we see with La Niña? • In the United States, La Niña is expected to bring above normal temperatures throughout most of the Southwest and southern Florida in the late summer and fall. • These warmer conditions will extend across the Southeast during the winter months. Cooler than normal winter temperatures are expected in the Pacific Northwest. Cooler than normal temperatures are also expected across the Great Lakes and Northeast later in the winter into spring. • In addition to temperature effects, La Niña is also expected to affect rainfall. Drier than normal conditions will persist in west Texas, New Mexico and Arizona into October. • The late fall and early winter forecasts indicate continued dry conditions throughout much of the southern U.S. and into portions of the Midwest. • Above normal precipitation is predicted for much of the Pacific Northwest throughout the fall and into the winter months, and in the Ohio and Tennessee River Valley in the winter.
Ice Ages/Interglacial Intervals • Ice Ages- When glaciers have covered large portions of the earth’s surface over the past 2 millions years • Over this time period, earth has experienced periods of ice and periods of warmth called interglacial intervals. • Ice ages can last between 60,000-100,000 years • Interglacial periods can last between 10,000-15,000 years • Right now, we are in an interglacial period that began 11,500 years ago. • Ice cores record climate similar to tree rings .
Climatic Changes… • Other things can cause climatic changes as well such as: • Meteorites collisions, large volcanic eruptions can suspend solid particles or liquid droplets into the air • Changes in solar output (energy given off by the sun) • Movement of earth’s crustal plates • Earth’s movement in space
Other things can cause climatic changes as well such as: • Meteor collisions and large volcanic eruptions can suspend solid particles such as dust or ash as well as liquid droplets into the air blocking solar radiation and cooling earth • Changes in solar output due to sun spots • Movement of earth’s crustal plates can shift ocean waters and form large mountains that can affect transfer of heat • Movement of Earth in Space • Earth’s tilt can change a few degrees (every 41,000 yrs) • Movement of earth on it’s axis can wobble • Shape of earth’s orbit can vary (every 100,000 yrs)
The Greenhouse Effect • Thegreenhouse effect is the heating of our earth due to certain gases being trapped in our atmosphere. • When radiation from the sun hits earth’s surface, some of this heat is absorbed into the earth and some is radiated back into space. • These gases that are in our atmosphere like to absorb and lock in some of this radiation similar to an invisible dome and cause climate changes.
The Greenhouse Effect • What are these gases that lock in this heat??? • The most important ones are: • Water Vapor • Carbon Dioxide (CO2) • Methane • Do we even need these gases to survive? YES, but at the same time, too much of them are hurting our climate
Global Warming • Over the past 100 years, the average surface temperature on earth has increased by about 1 degree. • This increase in temperature is known as global warming. • Over the past 100 years, CO2 has also increased by around 20%. • Scientists think that this increase of CO2 is causing global warming. • Others think it might be caused by changes in energy emitted by the sun.
Global Warming • What could happen if earth’s temperature continues to rise? • Glaciers could melt • If glaciers melt, sea level could rise • If sea levels rise, flooding could occur • If organisms can adapt to their environments, how will they be able to adapt to warmer temperatures?
Human Activities • What type of human activities can affect climate change? • The burning of fossil fuels such as oil, coal and natural gas for energy. • This releases carbon into the air which combines with oxygen creating large amounts of CO2.
Human Activities • Deforestation is the destroying and cutting of trees to build roads/buildings, mine, farm and graze cattle. • Tropical forests have been decreasing at a rate of about 1% each year for the past 20 years. • Why do we need trees? Trees take in CO2 and help us rid of the large amounts in our atmosphere.
The Carbon Cycle • All livings things are made of carbon. • Carbon, as CO2, is constantly recycles in nature. • Organisms that use photosynthesis take in CO2 to produce food. • CO2 is released as food is broken down. • When organisms die, CO2 is released into the atmosphere. • Some OC2 is dissolved into the ocean.
The pattern of weather that occurs in an area over a long period of time.
