Weather vs Climate! What!are!the!!four!factors!that!determine!weather?!!

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1 Name: Adv: Weather vs Climate Whatarethefourfactorsthatdetermineweather? Writeadefinitionforweather: Writeadefinitionforclimate: Weather Climate vs..

2 Layers & Composition of the Atmosphere Atmosphere.definition:.. Composition.of.the.Atmosphere:. 78% 21% 1%. Layers.of.the.Atmosphere:.. THERMOSPHERE. MESOSPHERE. STRATOSPHERE. TROPOSHERE. EARTH s.surface.

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4 WeatherVSClimateTeacherNotes Four Factors that Determine Weather Solar Distance Earths distance from the sun changes throughout its orbit, resulting in up to a 4 degree Fahrenheit difference between the closest and furthest points. The oscillating tilt of the planet creates much larger weather effects, because the tilt toward or away from the sun over the course of the year determines the amount of heat that part of the planet will receive. When a hemisphere is tilted toward the sun, that part of the planet experiences summer, whereas when it is tilted away, winter. Latitudinal Location Where on Earth you are also affects the weather. At the equator, for instance, weather does not change much, because that latitude always receives roughly the same amount of sunlight: around 12 hours a day. As you move away from the equator, however, you receive more or less sunlight, depending on the season. Polar regions experience extremely long days in summer and extremely long nights in winter. Both summer and winter temperatures also cool gradually as you move north or south of the equator. Air Pressure Solar radiation heats the planet, but it does not do so evenly. Air pressure is influenced by the differences between hotter and cooler pockets of air, or fronts. When the pockets are very different in temperature, they try to mix together, creating movement and pressure. When they aren t very different, the atmosphere moves around less -- resulting in, usually, fewer weather effects. As air attempts to equalize by moving from high pressure areas to low pressure areas, this causes wind. Additionally, when pressure is low, air is rising, which often means moisture accumulation in the atmosphere. Moisture accumulation forms clouds, which then produce rain or snow -- depending on air temperature -- once they get to their saturation point. When atmospheric pressure is low, air is pushed down toward the surface, meaning rain and moisture dont accumulate. This often also leads to high humidity near the surface of the Earth, where people experience weather. Water Presence The presence of water has a significant impact on weather. Nearby bodies of water add moisture to the atmosphere in the form of evaporation, which is why places near oceans or lakes, for instance, are usually wetter than the desert. Additionally, large bodies of water create winds as temperature differentials between land and water send breezes inland during the day and out to sea or onto lakes at night. Evaporating water forms different types of clouds: cirrus, which are high in the atmosphere and made of ice, stratus, which form lower down and consist of a thick, white blanket of rain drops, and cumulonimbus, which pile high and signal harsh weather, such as thunder, lightning, hail and tornadoes.

5 WEATHER What Weather Means Weather is basically the way the atmosphere is behaving, mainly with respect to its effects upon life and human activities. The difference between weather and climate is that weather consists of the short-term (minutes to months) changes in the atmosphere. Most people think of weather in terms of temperature, humidity, precipitation, cloudiness, brightness, visibility, wind, and atmospheric pressure, as in high and low pressure. In most places, weather can change from minute-to-minute, hour-to-hour, day-to-day, and seasonto-season. Climate, however, is the average of weather over time and space. An easy way to remember the difference is that climate is what you expect, like a very hot summer, and weather is what you get, like a hot day with pop-up thunderstorms. Things That Make Up Our Weather There are really a lot of components to weather. Weather includes sunshine, rain, cloud cover, winds, hail, snow, sleet, freezing rain, flooding, blizzards, ice storms, thunderstorms, steady rains from a cold front or warm front, excessive heat, heat waves and more. CLIMATE What Climate Means In short, climate is the description of the long-term pattern of weather in a particular area. Some scientists define climate as the average weather for a particular region and time period, usually taken over 30-years. Its really an average pattern of weather for a particular region. When scientists talk about climate, theyre looking at averages of precipitation, temperature, humidity, sunshine, wind velocity, phenomena such as fog, frost, and hail storms, and other measures of the weather that occur over a long period in a particular place. For example, after looking at rain gauge data, lake and reservoir levels, and satellite data, scientists can tell if during a summer, an area was drier than average. If it continues to be drier than normal over the course of many summers, than it would likely indicate a change in the climate. Why Study Climate? The reason studying climate and a changing climate is important, is that will affect people around the world. Rising global temperatures are expected to raise sea levels, and change precipitation and other local climate conditions. Changing regional climate could alter forests, crop yields, and water supplies. It could also affect human health, animals, and many types of ecosystems. Deserts may expand into existing rangelands, and features of some of our National Parks and National Forests may be permanently altered.

6 Earths atmosphere The Earths atmosphere is an envelope of gas that surrounds the Earth and extends from the Earths surface out thousands of kilometres, becoming increasingly thinner (less dense) with distance but always held in place by Earths gravitational pull. The atmosphere contains the air we breathe and it holds clouds of moisture (water vapor) that become the water we drink. It protects us from meteors and harmful solar radiation and warms the Earths surface by heat retention. In effect, the atmosphere is an envelope that protects all life on Earth. The atmosphere is a mixture of gases that we call air. On a dry volume basis, it consists of about 78 percent nitrogen and 21 percent oxygen. The remainder of about one percent consists of argon, carbon dioxide and very small amounts of other gases. The atmosphere is rarely, if ever, completely dry. Water vapor is almost always present up to about four percent of the total volume. In desert regions, when dry winds are blowing, water vapor in the air will be nearly zero. This climbs in other regions to about three percent on extremely hot and humid days. The upper limit, approaching four percent, applies to tropical areas. The atmosphere has a total mass of about metric tons and approximately 80% of that mass is within about 12 kilometres (7.5 miles) from the Earths surface. There is no definite boundary between the atmosphere and outer space. It slowly becomes less dense (i.e., more empty) with increasing altitude and fades into the void of outer space.

7 Structure of the atmosphere As shown in the adjacent diagram, Earths atmosphere has five primary layers, referred to as spheres. From the lowest to the highest layer, they are: Troposphere From the Greek word "τρ?πω" meaning to turn or change. The troposphere is the lowest layer of the atmosphere and extends from the Earths surface to about 7 kilometres (4 miles) high at the north and south poles and 17 kilometres (11 miles) high at the equator. This is where we live. As the density of the air in this layer decreases with height, the airtemperature also decreases with height. The temperature drops from about 14 to 15 C at the surface to about &45 C at the top of the troposphere. All of our weather occurs in the troposphere. The troposphere contains about 80% of the total mass of the atmosphere. In fact, 50% percent of the total mass of the atmosphere is located in the lowest 5 to 6 kilometres (3.1 to 3.7 miles) of the troposphere. The cruising altitude of commercial airliners is usually about 9 to 10 kilometres (5.6 to 6.2 miles) which is close to the top of the troposphere. Atmospheric boundary layer The lowest part of the troposphere is called the atmospheric boundary layer (ABL) or the planetary boundary layer and extends from the Earths surface to about 1.5 to 2.0 km in height. The air temperature of the atmospheric boundary layer decreases with increasing altitude unless an inversion layer, where the temperature increases with increasing altitude, is present. Above an inversion layer, the temperature decreases again. (See also Atmospheric lapse rate) Tropopause The boundary between the troposphere and the stratosphere. Together, the troposphere and the tropopause are known as the lower atmosphere.

8 Stratosphere From the Latin word "stratus" meaning spreading out. The stratosphere extends from the tropopauses height of 7 to 17 kilometres (4 to 11 miles) to a height of about 50 kilometres (31 miles) and contains about 19% of the atmospheric gases. The stratosphere experiences increasing temperature and solar radiation with height. It contains the ozone layerbecause the solar radiation is increasingly absorbed by oxygen molecules in the stratosphere, leading to the formation of ozone. The ozone layer resides in the lower portion of the stratosphere, though the thickness of the layer varies seasonally and geographically. Weather balloons can rise to about 40 kilometres (25 miles) before the difference between the pressure inside the balloon and the outside atmospheric pressure causes the balloons to expand to the point at which they burst. Stratopause The boundary between the stratosphere and the mesosphere. The atmospheric pressure here is 1/1000th of the atmospheric pressure at sea level. Mesosphere From the Greek word "µ?σος" meaning middle. The mesosphere extends from stratopauses height of about 50 kilometres (31 miles) to a height of about 80 to 85 kilometres (50 to 53 miles). The gases continue to become less and less dense with height. As such, the effect of the warming by ultraviolet radiation also becomes less and less, leading to a decrease in temperature with height. On average, temperature decreases to as low as &100 C at the mesopause. However, the gases in the mesosphere are still dense enough to slow down meteors hurtling into the atmosphere, where they burn up and leave fiery trails in the night sky. Mesopause The boundary between the mesosphere and the thermosphere. It is the coldest place on Earth, with a temperature as low as -120 C at times. Thermosphere The thermosphere extends from the mesopauses height of 80 to 85 kilometres (50 to 53 miles) to a height of between 500 and 1000 kilometres (310 and 620 miles) and is referred to as the upper atmosphere. The gases of the thermosphere are increasingly less dense than in the mesosphere. As such, incoming high energy ultraviolet and x-ray radiation from the sun, absorbed by the molecules in this layer, results in the temperature increasing to as high as 2000 C near the top of this layer. However, despite the high temperature, this layer of the atmosphere would still feel very cold to our skin because of the extremely low density of the air. The total amount of energy from the very few molecules in this layer is not enough to heat our skin. The International Space Station orbits in this layer, between 320 and 380 kilometers (200 and 235 miles) from the Earths surface. The Kármán line, named after the physicist Theodore von Kármán, is in the thermosphere at an altitude of 100 kilometres (62 miles) above the Earth and is often referred to as the boundary between Earths atmosphere and outer space. Thermopause The boundary between the thermosphere and the exosphere.

9 Don t&need&to&review& &but&in&case&kiddos&ask&questions:& Exosphere Extends from the thermopauses height of 500 to 1000 kilometres (310 to 620 miles) up to a height of 10,000 kilometres (6,200 miles) above the Earths surface. The exosphere is the outermost layer of the atmosphere and it is in this layer that our man-made satellites orbit the Earth. The density of the exosphere is so low that particles within it (atoms, molecules, or ions) do not collide. As a result, particles in the exosphere can escape altogether from Earths atmosphere into the void of space. There are two other regions of the atmosphere that deserve discussion, one is the ionosphere and the other is the ozone layer&: Ionosphere Solar radiation causes ionization of the molecules in a region of the atmosphere that extends from approximately 50 kilometers up to about 1100 kilometers above the Earth. That region is called the ionosphere and most of it is in the thermosphere, although it overlaps into the exosphere above the thermosphere and the mesosphere below the thermosphere. It is of importance because certain regions of the ionosphere make long distance radio communication possible by reflecting the radio waves back to Earth. It is also home to auroras. The lower edge of auroras occur at an altitude of approximately 100 kilometres (about the same height as the Kármán line) and may extend up to an altitude of 480 kilometres Ozone Layer Though part of the stratosphere, the physical and chemical composition of the ozone layer is far different from that of the stratosphere. Ozone (O 3 ) in the Earths stratosphere is created by ultraviolet light striking oxygen molecules containing two oxygen atoms (O 2 ), splitting them into individual oxygen atoms (atomic oxygen). The atomic oxygen then combines with unbroken O 2 to create O 3, the ozone. Ozone is unstable (although long-lived in the stratosphere) and when ultraviolet light hits ozone, it splits into a molecule of O 2 and an atom of atomic oxygen thus creating a continuing process called the ozone-oxygen cycle. This occurs in the ozone layer, the region from about 10 to 50 kilometres (6 to 31 miles) above Earths surface.

10 About 90% of the ozone in the Earths atmosphere is contained in the stratosphere. Ozone concentrations are greatest between the heights of about 20 and 40 kilometres above the Earths surface, where they range from about two to eight parts per million by volume. Sometimes the Earths atmosphere is defined as consisting of these two parts: Homosphere: Defined as that part of the atmosphere where the chemical composition of the atmosphere is constant. The homosphere extends from the Earths surface to about 80 kilometres (50 miles) and includes the troposphere, the mesosphere and the stratosphere. Heterosphere: Defined as that part of the atmosphere above 80 kilometres in which the component gases are stratified, with concentrations of the heavier gases decreasing more rapidly with altitude than concentrations of the lighter gases. It includes the thermosphere and the exosphere.