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First edition: MAY 2012

Authors: Joaquin Bustamante, Rafaela Tamayo and Mateo Molina

Editor: Michael Jones

Table Of Contents

Sun and Wind pg. 3

The Sun and its impact on Ocean Currents pg. 4

The Sun and the Water Cycle,

Sun and Plant Growth pg. 5

Earth’s Seasons pg. 6

Energy in the atmosphere pg. 7-8

Wind/Global patterns pg. 8-9

Work Cited pg. 10-11

Sun and its effect on Wind

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Winds are caused by the Sun. The Sun is the Earth’s ultimate source of energy. The heating of air masses creates winds in different order. This heating created two types of winds.

Local winds:

Local winds are what you feel outside your house from time to time. They are fast winds in the atmosphere traveling really fast. The unequal heating of the air masses, due to the Sun, created these winds. The unequal heating also created changes in pressure.

Global winds:

These are the big winds that circle Earth. For this scientist use the terms cells. There are enormous cells of wind that are located in the Atmosphere. The air in these cells is creating by temperature and pressure differences but also on the spin of Earth. The effect of the spinning Earth is called Coriolis Force. In the cells there is a big rotating on the air. Heated air rises and cooler air fills the space that was left by the hot air.

The Sun and its impact on Ocean Currents

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The Sun has two main effects on the ocean. The Sun heats the atmosphere, creating winds that move the sea surface through friction, creating waves. This drags the water over the surface. The wind strongly affects the surface of the ocean.

The second effect of the Sun is to alter the density of the ocean surface water. The Sun changes its temperature and/or its salinity through evaporation. If water is cooled or becomes saltier, through evaporation, because water

leaves the ocean leaving a higher salt density, it becomes denser. This causes the water column becoming unstable, setting up density-dependent currents, also known as the thermohaline circulation.

Currents are rivers of water that move in the ocean. There are two types of currents the surface current and the deep ocean current. The surface current is created by wind (wind is created by the Sun), which drags the water. Deferring from the surface currents the deep ocean currents are form because of the difference in density and temperature. Since the Sun changes the density and the temperature of the ocean it forms the currents. The denser water flows under the less dense causing the less dense water to rise.

The Sun and the Water Cycle

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The Sun has a direct impact on the Water cycle. The water cycle consists on water evaporating from the ocean; condensing in the

atmosphere, forming clouds; the water falls from the cloud as precipitation; the water gets to rivers and lakes through runoff; eventually the water will end up in the ocean or evaporate in the path casing the cycle to start again. Sun is

required to provide enough energy for the water to evaporate.

Sun and Plant Growth

Plants such as trees and flowers depend directly on sunlight to live and grow. The Sun induces photosynthesis and feeds the plants energy. Photosynthesis is the process in which plants use the energy from the Sun to produce food from carbon dioxide and water. A pigment called chlorophyll absorbs the Sun’s

energy in order to perform their vital functions. It generates oxygen as a byproduct. Plants depend on sun energy to grow and produce oxygen. Without sunlight, plants would be unable to produce oxygen therefore animal (human) life would not be possible.

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Earth’s Seasons

Seasons on Earth are a result of the tilt in Earth’s axis. There are four main seasons, which are spring, summer, autumn (fall) and winter. Since the axis is tilted, different parts of Earth faces the Sun at different times of the year. Summer is hotter/warmer than winter because the Sunrays hit that part of the

hemisphere at a more direct angle. Also, because the days are much longer than the nights during the summer.

There are some days in which “the Sun reaches its farthest northern and southern declinations.”(Enchanted Learning) There are two solstices in the year. The winter solstice takes place on December 21 or 22 and marks the beginning of winter, making it the shortest day of the year. And the Summer solstice takes place on June 21 and marks the beginning of summer, making it the longest day.

There are other types of days called equinoxes. Equinoxes are days in which day and night last the same amount of time. They happen when the Sun crosses the celestial equator. The vernal equinox occurs in late March (this is the beginning of spring in the Northern Hemisphere and the beginning of fall in the Southern Hemisphere); the autumnal equinox happens in late September (this is the

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beginning of fall in the Northern Hemisphere and the beginning of spring in the Southern Hemisphere).

Energy in the Atmosphere

Energy from the atmosphere is transferred by conduction radiation and convection.

ConvectionConvection transmits heat by transporting groups of molecules from

place to place within a substance. It occurs in fluids like water and air that can move freely. Convection currents happens when hot air rises and cold air sinks. When rising of cold air occurs they can help to the development of clouds and storms. The warm air at the equator

spreads northward and southward, and the cold air from the poles spreads toward the equator. This makes 2 convection cells formed. The rotation of the earth towards the east makes the air go to the right in the northern hemisphere. This deflection of air is called Coriolis Effect.

ConductionConduction is the process in which heat is transferred through contact

with neighboring molecules. Air is a poor conductor, for that reason most the energy is conducted through the earth surface. When its night the ground gets colder and the ground conducts heat away from the air. At

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the other side during the day ground gets heated by solar radiation and then it heats the air by conduction.

Radiation Almost all of the suns radiant energy is in the visible and near visible

portions of the spectrum. Shorter than visible wavelengths are a small percentage but they are extremely important because they have higher energy, these are known as the ultraviolet wavelengths.

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Wind

Inside the atmosphere, there is air moving from place to place. That air moving is called wind. Wind is what happens when the sun heats earth the atmosphere unevenly. Wind speed and force can vary from a gentle breeze to a hurricane. The types of winds are:

Sea Breeze:

The air in the land heats up, which causes the hot air to go up. Then, cold breezes from the ocean come to replace it. In a bit of time that current of air can travel miles. This effect is called convection. The same thing can happen near lakes or bodies of water.

Land Breeze:

At night, the wind cools down, and the same thing happens, only reversed.

Global Patterns

Forces like the ones above also affect on climate. For example, the tropics are always hot, so hot air rises here and starts going north and south, spreading miles above. Below that, breezes from the north and south are pulled in, another example of convection. The Coriolis Effect makes the wind travel in curves thanks to the Earth’s rotation. The wind currents in the equator come from north and south east (because the Earth spins that way). Some surface winds try to go towards the north and south but the Coriolis Effect makes them go west. In the north, cold air wants to go to the equator, but the Coriolis Effect makes it go east. Another way of saying this is: in the northern hemisphere the wind

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goes to the right (East) and in the southern hemisphere the wind blows to the left (West).

Wind goes from areas with high pressure to areas with low pressure. The Coriolis Effect makes them curve, and spiral, so that’s why the wind is always changing direction. When cold air gets to the center of a low pressure area, the cold air goes up, and it carries moistness with it and creates storm. In the center of high pressure areas, dry wind comes down and makes normal weather.

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Work Cited

Frank, Marjorie S., Robert M. Jones, Gerald H. Krockover, Mozell P. Lang, Joyce C. McLeod, Carol J. Valenta, and Barry A. Van Deman. “Patterns on Earth and in Space.” Harcourt Science. Orlando, FL: Harcourt School, 2005. D6-D17. Print.

“EARTH’S Seasons – Zoom Astronomy.” EARTH’S Seasons – Zoom Astronomy. Web. 13 May 2012.

<http://www.enchantedlearning.com/subjects/astronomy/planets/ earth/Seasons.shtml>.

“Water Encyclopedia.” Ocean Currents. Web. 13 May 2012. <http://www.waterencyclopedia.com/Mi-Oc/Ocea-Currents.html>.

Smestad, Abigail. “The Effect of Light on Plant Growth.” EHow. Demand Media, 31 July 2009. Web. 13 May 2012. <http://www.ehow.com/about_5251025_effect-light-plant-

growth.html>.

“Introduction to the Atmosphere.” : Background Material. Web. 13 May 2012. <http://www.ucar.edu/learn/1_1_1.htm>.

Images:

"Windows to the Universe." Windows to the Universe. Web. 17 May 2012. <http://www.windows2universe.org/earth/Atmosphere/earth_atmosph_radiation_budget.html>.

Web. 17 May 2012. <http://cimss.ssec.wisc.edu/sage/meteorology/lesson1/concepts.html>.

"ThinkQuest : 404." ThinkQuest. Oracle Foundation. Web. 17 May 2012. <http://library.thinkquest.org/29033/begin/earthsunmoon.htm>.

Web. 17 May 2012. <http://www.shutterstock.com/pic-63965368/stock-photo-growth-or-new-life-concept-with-small-plant-sun-and-copyspace.html>.

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Web. 17 May 2012. <http://www.all-water.org/Water_Cycle.html>.

"Windows to the Universe." Windows to the Universe. Web. 17 May 2012. <http://www.windows2universe.org/earth/climate/cli_effects.html>.

"Wind Day « Switching Things up a Bit." Switching Things up a Bit. Web. 17 May 2012. <http://sfaulhafer.wordpress.com/2012/03/12/wind-day/>.

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