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WWK?. What kind of activities result in significant changes in Earths climate. The Forces in Nature.
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WWK? What kind of activities result in significant changes in Earths climate
The Forces in Nature Natural events are some of the most powerful and destructive forces in nature. We witness and hear about these natural catastrophes all the time, but do we know what causes them? What do they do besides destroy? Today you will learn how such events can alter and affect the Earth and its climate. By the end of this PowerPoint you should know about…. Disasters to Learn About…- Tornadoes and Cyclones- Thunderstorms - Hurricanes
Tornadoes and Cyclones A tornado is a violent, dangerous, rotating column of air that is in contact with both the surface of the earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. They are often referred to as a twister or a cyclone, although the word cyclone is used in meteorology in a wider sense, to name any closed low pressure circulation. Out of all the natural disasters listed, tornadoes and cyclones are rated the highest in destructive force due to their ability to easily tear through most, if not everything, that is placed in their way. A mesocycloneis a vortex of air, approximately 2 to 10 miles in diameter (the mesoscale of meteorology), within a convective storm. That is, it is air that rises and rotates around a vertical axis, usually in the same direction as low pressure systems in a given hemisphere. They are most often cyclonic, that is, associated with a localized low-pressure region within a severe thunderstorm.
Thunderstorms Thunderstorms are a form of weather characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere known as thunder. They are usually accompanied by strong winds, heavy rain and sometimes snow, sleet, hail, or no precipitation at all, and those that do include hail are commonly known as hailstorms. Although thunderstorms are not very dangerous, they are known to cause around 1% of all tornadoes and usually accompany other natural disasters. Doppler Radars (specialized radar that makes use of the Doppler effect to produce velocity data about objects at a distance) are used in order to detect such events by beaming signals and examining the changes such upcoming disasters have placed upon them.
Hurricanes A hurricane is a storm system characterized by a large low-pressure center and numerous thunderstorms that produce strong winds and heavy rain. Hurricanes strengthen when water evaporated from the ocean is released as the saturated air rises, resulting in condensation of water vapor contained in the moist air. While a hurricane can produce extremely powerful winds and torrential rain, they are also able to produce high waves and damaging storm surge as well as spawning tornadoes. They develop over large bodies of warm water, and lose their strength if they move over land due to increased surface friction and loss of the warm ocean as an energy source.
WWK? The uneven distribution of solar energy on earths surface.
The Earth Is tilted... The earth’s axis is hot straight up and down. The earths axis is tilted. Because of this, certain parts of the earth lean towards the sun at different times during the year. This is what causes the changes of seasons.
Seasons… If you live on a part of earth that is leaned towards the sun, its going to be summer where you are. If you live on an areas leaned away, it is winter where you are. When the earth is going between these two spots, you have equinox, which is the daytime and night time are equal, because the earth is not tilted toward or away from the sun.
Equinoxes/solstices Equinoxes and solstices mark when the earth has revolved enough to have a different tilt with the sun, thus changing seasons.
WWK? How the atmosphere is heated from earths surface.
WWK? How changing surface and ocean conditions effect weather and climate patterns.
Convective heat transfer is one of the major modes of heat transfer and convection is also a major mode of mass transfer. Convective heat and mass transfer take place through both diffusion – the random Brownian motion of individual particles in the fluid – and by advection, in which matter or heat is transported by the larger-scale motion of currents in the fluid. • In the context of heat and mass transfer, the term "convection" is used to refer to the sum of advective and diffusive transfer. Sometimes "convection" is even used to refer specifically to "free heat convection" (natural heat convection), as opposed to forced heat convection. • This heat energy is transferred through the atmosphere by one of three mechanisms: • 1. Radiation • 2. Conduction • 3. Convection • Conduction is the transfer of heat from one molecule to another within a substance. • Convection is the transfer of heat through the movement of a fluid, such as water or air. • Radiation is the type of heat transfer can be observed on sunny days. • Solar Distribution is the distribution of sunlight on earths surface. • Albedo is the fraction of the total radiation that is reflected by a surface.
Convection is the process by which heat is moved from one place to another by the upwelling or down welling of a fluid, such as air or water. • Convection occurs in the troposphere, the lowest region of Earth's atmosphere. It is the cause of surface winds and weather. Above the troposphere, in the mesosphere and stratosphere the air is calm. • Straddling the stratosphere and mesosphere is the ozone layer, where incoming solar ultraviolet radiation is absorbed. At even higher altitudes is the ionosphere, where the atmosphere is kept ionized by high-energy radiation and particles from the Sun. • Between 50 and 80 km from the surface lies the mesosphere.
WWK? El Niño and its effects on the earth.
El Niño is characterized by unusually warm ocean temperatures in the equatorial pacific. • La Nina is characterized by unusually cold ocean temperatures in the equatorial pacific.
It happens roughly every five years • It causes extreme weather, like floods and droughts. • Countries dependent on agriculture and fishing, particularly bordering the pacific ocean are most affected
First signs of el Niño: Rise in surface pressure over Indian ocean, Indonesian, and Australia. Fall in air pressure over Tahiti in the rest of the central and eastern Pacific ocean. Trade winds in the south pacific weaken or heightened. Warm air rises near Peru casing rain in the northern Peruvian deserts. Warm water spreads from the W. pacific and the Indian ocean to the E pacific takes the rain with it causing extensive drought in the w pacific and rainfall in the normally dry eastern pacific
WWK? The formation of air masses and their movement.
An air mass: is a large body of air relatively similar temperature and humidity charactestics covering thousands of square kilometers. • Air masses are classified according to the characteristics of their source region or area of formation. • A source region can have one of 4 temperature attributes: equatorial, tropical polar, or arctic.
Air masses are also classified as being either continental or maritime in terms of moisture characteristics. • 7 possibilities are commonly found in north America when combining the 2 categories: maritime polar, continental polar, maritime tropical, continental tropical, continental arctic. • Front Types are the boundary between two adjoin air masses having constant contract.
Frequently, 2 air masses usually in the middle latitudes, develop a sharp boundary of interface where the temperature difference between them becomes intensified, that is called a frontal zone or front. • Warm fronts move about 10 kilometers per hour in a north east direction. • When most of these fronts move together it sometimes causes heavy wind mix which leads to tornados and massive cyclones.